Specimen index · the complete record · 1996–2026

Fifty-six sealed cells.

The whole corpus, banked in the order it was granted and grouped by the six lines of work — 8 of them with David A. Ruben as sole inventor. Each row is a sealed cell: touch it and it unseals, showing a plain reading, a drawing lifted from the patent and inverted into phosphor, and the way through to the original or the full dossier.

grants61
lines6
sole inventor8
span1996–2026

flagship of its line · major work

Line One · 22 grants

Hermetic Packaging & Feedthroughs

An implantable device is a promise: nothing leaks in, nothing leaks out, for a decade or more, in warm salt water. This cluster is thirty years of keeping that promise — from the 1993 housing that let a pacemaker be assembled like a microchip, to laser-bonded feedthroughs that pass signals through sapphire walls with nanometer-scale seals, to testing structures that prove the seal is real (US7902851). If the corpus has a thesis statement, it is here.

1996 ◆ Implantable medical device including a first enclosure portion having a feedthrough in a second interior surface US 5,535,097 · 100 citations

Filed in 1993, this is where the corpus begins. Pacemakers were then built as welded clam-shells crowded with separate positioning parts; this design reshapes the can's interior so battery, circuit, and feedthrough each drop into a ready-made seat before one lid seals it shut — fewer parts, fewer steps, and a rounded contour kinder to the tissue it lives in. A hundred later patents cite it: the seed of thirty years of packaging work.

The lid pulled away from the shell, with connector block, setscrew, spring contact, and feedthrough floating in position — a freeze-frame of the housing assembling itself. — Phosphor plate · US 5,535,097
The lid pulled away from the shell, with connector block, setscrew, spring contact, and feedthrough floating in position — a freeze-frame of the housing assembling itself. US patent drawing — public domain.

Read the patent → The full dossier

1998 Protective Feedthrough US 5,759,197

An implanted pacemaker or defibrillator has to let electrical signals pass through its sealed metal case without ever breaking the hermetic seal that keeps body fluids out. This early Medtronic feedthrough seals a conductor pin through an insulated ferrule and adds a nearby conductive block, shaped so that an ordinary flat chip capacitor can simply bridge the two and shield the internal electronics from stray electrical and electromagnetic interference. It made electrical protection something you could bolt onto a standard sealed feedthrough instead of building a special filtered part.

Cross-sectional view (FIG. 3) of the protective feedthrough: a conductor pin passes through an insulator-filled ferrule sealed in the case, while a flat chip capacitor bridges the gap between the ferrule's upstanding rim and the skirt of the conductive block above it. — Phosphor plate · US 5,759,197
Cross-sectional view (FIG. 3) of the protective feedthrough: a conductor pin passes through an insulator-filled ferrule sealed in the case, while a flat chip capacitor bridges the gap between the ferrule's upstanding rim and the skirt of the conductive block above it. US patent drawing — public domain.

Read the patent → The full dossier

2007 Assembly including a circuit and an encapsulation frame, and method of making the same US 7,288,847

Encapsulant faces a paradox: it must flow freely enough to infiltrate a circuit's every crevice, yet not flood the board — and molded walls leak at post holes and cost too much. Ruben's first-listed answer is geometry: a flat frame, thermally matched to the substrate, whose through-hole corrals the encapsulant around the components, with extra openings that deliberately keep contacts and ID codes exposed for later assembly steps. A dam instead of a mold — cited 13 times, including by Shindengen.

The frame with its window-shaped well, the circuit board it guards, and a perspective of the two being brought together. — Phosphor plate · US 7,288,847
The frame with its window-shaped well, the circuit board it guards, and a perspective of the two being brought together. US patent drawing — public domain.

Read the patent → The full dossier

2010 Encapsulation circuitry on a substrate US 7,682,878

Protecting a finished circuit means covering it in encapsulant that must be runny enough to seep around every component yet thick enough not to pour off the board. This continuation extends the encapsulation-frame idea: a flat frame, matched to the board's thermal expansion, whose through-hole wall dams the liquid right where it is needed. Even its extra holes are practical, leaving contacts and ID codes exposed for the next step on the production line.

The flat encapsulation frame and the circuit board it protects, with a perspective view of the frame being lowered onto the populated board. — Phosphor plate · US 7,682,878
The flat encapsulation frame and the circuit board it protects, with a perspective view of the frame being lowered onto the populated board. US patent drawing — public domain.

Read the patent → The full dossier

2011 ◇ Hermeticity testing US 7,902,851 · 23 citations

Moisture is the quiet killer of implanted electronics, and the seam between two bonded chips is exactly where a micro-package is most vulnerable — yet conventional tests can't see into that buried interface. So the test is built into the seal itself: tiny chain circuits on both chips mate at bonding into rings around each sealed region, and moisture creeping in breaks or shorts a chain at the perimeter before the electronics are ever at risk. Not making the seal — proving it, electrically, from the inside.

Two chips poised face-to-face before bonding, with the small test contacts that will mate into a seal-checking circuit around the protected region. — Phosphor plate · US 7,902,851
Two chips poised face-to-face before bonding, with the small test contacts that will mate into a seal-checking circuit around the protected region. US patent drawing — public domain.

Read the patent → The full dossier

2013 Hermetic wafer-to-wafer bonding with electrical interconnection US 8,433,402

Building an implantable device from two bonded silicon wafers means the join has to do two jobs at once: carry electrical signals between the wafers AND seal the electronics hermetically against body fluid. This patent makes a single heated step do both — conductive pads set into vias on each wafer reflow, agglomerate, and merge, so the electrical interconnect IS the hermetic seal. One operation replaces two, at wafer scale.

Cross-sections of the stacked wafers: recessed conductive pads on each face that, when heated, reflow and merge — forming the electrical interconnect and the hermetic seal in the same step. — Phosphor plate · US 8,433,402
Cross-sections of the stacked wafers: recessed conductive pads on each face that, when heated, reflow and merge — forming the electrical interconnect and the hermetic seal in the same step. US patent drawing — public domain.

Read the patent → The full dossier

2017 Embedded metallic structures in glass US 9,832,867

Implant packages have to keep shrinking without giving up their airtight seal, and wiring that lives only on the surface wastes the walls. Here two glass wafers are fused with filled vias, conductive traces, and an insulating layer between them, turning the glass itself into three-dimensional wiring — even an antenna can be etched straight into the wafer, so the wall becomes a working radio component instead of mere enclosure. The interconnect industry noticed: four of the five visible follow-on citations come from connector maker Samtec.

Cross-section of the finished package: two glass wafers fused into one body, with a chip mounted inside and metal routing buried in the glass wall itself. — Phosphor plate · US 9,832,867
Cross-section of the finished package: two glass wafers fused into one body, with a chip mounted inside and metal routing buried in the glass wall itself. US patent drawing — public domain.

Read the patent → The full dossier

2018 ◆ Feedthrough assemblies (parent of the laser-bond feedthrough line) US 9,865,533

Every implantable device faces the same paradox: its electronics must be sealed away from body fluid absolutely, yet wires have to pass through the wall. This grant founded his answer — instead of baking glass and metal together at furnace temperatures, a laser traces a ring-shaped bond around each wire's passage, fusing it shut while the rest of the part stays cool. It grew from a provisional application filed on Christmas Eve 2014 and seeded a decade-long line of patents.

Laser beams fire up through the transparent substrate to weld a contact in place, beside a bullseye view of the ring-shaped bond encircling the wire's via. — Phosphor plate · US 9,865,533
Laser beams fire up through the transparent substrate to weld a contact in place, beside a bullseye view of the ring-shaped bond encircling the wire's via. US patent drawing — public domain.

Read the patent → The full dossier

2019 Sealed package and method of forming same US 10,420,509

Conventional hermetic housings hang their fate on feedthroughs built from ferrules, glass seals, and high-temperature brazing — complexity and stress concentrated at the one joint an implant cannot afford to lose. This grant, part of a four-patent chain with Craig L. Schmidt, continues the sealed-package alternative: a cavity in the substrate covered to form the enclosure, with each external contact laser-bonded in a ring around its via, heating only a whisper-thin surface layer.

A side cross-section of the sealed package — cavity, cover, and capped vias — above a top view of its grid of ten round external contacts. — Phosphor plate · US 10,420,509
A side cross-section of the sealed package — cavity, cover, and capped vias — above a top view of its grid of ten round external contacts. US patent drawing — public domain.

Read the patent → The full dossier

2019 Hermetic conductive feedthroughs for a semiconductor wafer US 10,464,836

How do you carry a signal out through a glass wall without giving body fluid a path back in? Here the conductor is entombed in the wafer itself — its outer face never reaches the surface directly, but takes a deliberate dog-leg through an embedded trace to a recessed cavity, so fluid can never follow the interface back inside. Filed in 2013, it founded the glass-wafer feedthrough line for making implants at wafer scale.

A cross-section of the implantable device with the feedthrough in its wall, and a close-up showing the conductor buried inside the glass rather than crossing straight through. — Phosphor plate · US 10,464,836
A cross-section of the implantable device with the feedthrough in its wall, and a close-up showing the conductor buried inside the glass rather than crossing straight through. US patent drawing — public domain.

Read the patent → The full dossier

2020 ◆ Feedthrough assemblies and methods of forming same US 10,535,596

This is the core articulation of the laser-bond feedthrough claim: a conductive via passes through a non-conductive substrate, and the contact capping it is hermetically sealed by a bond that surrounds the via — an interface that can be just tens of nanometers thin. Because the light delivers heat only where the joint forms, the wall can be glass, sapphire, or even silicon carbide, and the device can shrink without ever compromising the seal.

A cross-section catches the laser mid-weld, firing through the see-through substrate, with a plan view of the concentric ring-shaped bond zones around the wire. — Phosphor plate · US 10,535,596
A cross-section catches the laser mid-weld, firing through the see-through substrate, with a plan view of the concentric ring-shaped bond zones around the wire. US patent drawing — public domain.

Read the patent → The full dossier

2020 Sealed package and method of forming same US 10,765,372

In this continuation of the sealed-package line with Craig L. Schmidt, the package stops being a box that contains the device and becomes the device's own body: a cavity carved into the substrate, a cover layer sealing it shut, and a via carrying signals out to a contact laser-bonded in a ring around it. The laser heats only the surface layer where the joint forms — and the finished bond is stronger than the bulk substrate around it.

A bullseye view of one external contact with its ring-shaped bond, and a close-up cross-section showing the contact's via reaching down into the sealed cavity. — Phosphor plate · US 10,765,372
A bullseye view of one external contact with its ring-shaped bond, and a close-up cross-section showing the contact's via reaching down into the sealed cavity. US patent drawing — public domain.

Read the patent → The full dossier

2020 ◇ Hermetically-sealed packages including feedthrough assemblies US 10,813,238 · sole inventor

Where its sibling grants claim the feedthrough alone, this sole-inventor patent claims the whole sealed package built around it: the substrate carrying the laser-bonded contacts is integrated into the device's hermetic housing itself. It descends from one of the twin provisional applications filed on Christmas Eve 2014 — the branch of the feedthrough line he pursued under his name alone.

A cross-section of the sealed package with its feedthrough contacts, paired with a top-down view of one contact — the dark via at center ringed by its bond. — Phosphor plate · US 10,813,238
A cross-section of the sealed package with its feedthrough contacts, paired with a top-down view of one contact — the dark via at center ringed by its bond. US patent drawing — public domain.

Read the patent → The full dossier

2021 Sealed implantable medical device and method of forming same US 11,103,714

Feedthroughs are where hermetic seals leak, and high-temperature joining can alter the very materials it connects. This axial design sidesteps both: the external contact is sealed at one end of the housing, and electricity crosses to the electronics inside through a conductive member held under compression — connection by pressure, not bonding. The housing can even be transparent glass or sapphire, letting an optical sensor read the body straight through the wall with no extra opening.

The capsule-shaped device seen whole and pulled apart along its axis — end caps, seal rings, and the electronics that slide into the tube. — Phosphor plate · US 11,103,714
The capsule-shaped device seen whole and pulled apart along its axis — end caps, seal rings, and the electronics that slide into the tube. US patent drawing — public domain.

Read the patent → The full dossier

2022 Sealed package and method of forming same US 11,419,552

Traditional hermetic feedthroughs are little assemblies of ferrules, glass seals, and high-temperature brazing — manufacturing complexity and material stress at the most critical joint in the device. This continuation refines the alternative: a substrate with a sealed cavity that is itself the device body, each electrical contact laser-bonded in a ring around its via. The laser heats only the surface layer it touches, and the finished bond is stronger than the bulk of the substrate around it.

A bullseye top view of one contact ringed by its bond line, above a close-up cross-section with laser energy firing up through the substrate to weld it in place. — Phosphor plate · US 11,419,552
A bullseye top view of one contact ringed by its bond line, above a close-up cross-section with laser energy firing up through the substrate to weld it in place. US patent drawing — public domain.

Read the patent → The full dossier

2022 Hermetic conductive feedthroughs for a semiconductor wafer US 11,485,670

As implants shrink, the wired doorways through their walls have to shrink too — and conventional feedthrough builds don't miniaturize reliably. Here the conductor is entombed inside a glass wafer, its outer face never reaching the surface directly: the path out takes a deliberate dog-leg through a buried trace to a recessed cavity, so body fluid can't follow the wire back in. Defense in depth for electrons, built at wafer scale.

Cross-sections of the glass-wafer package: the sealed cavity in full, and a close-up of the buried feedthrough whose conductive trace jogs sideways beneath the surface. — Phosphor plate · US 11,485,670
Cross-sections of the glass-wafer package: the sealed cavity in full, and a close-up of the buried feedthrough whose conductive trace jogs sideways beneath the surface. US patent drawing — public domain.

Read the patent → The full dossier

2023 ◇ Sealed package and method of forming same US 11,744,518

Traditional implant housings are built up from ferrules, glass seals, and high-temperature brazing, each one a source of manufacturing complexity and material stress. This grant is the mature form of a different idea: hollow a cavity into the substrate itself, seal a cover layer over it, and laser-bond each electrical contact in a ring around its via — the package is the device body. The laser heats only the surface layer it touches, and the finished bond is stronger than the surrounding material.

A cross-section of the sealed package — electronics enclosed in a cavity between substrate and cover — beside a top view of its grid of feedthrough contacts. — Phosphor plate · US 11,744,518
A cross-section of the sealed package — electronics enclosed in a cavity between substrate and cover — beside a top view of its grid of feedthrough contacts. US patent drawing — public domain.

Read the patent → The full dossier

2024 Hermetic assembly and device including same US 11,865,639

Joining a ceramic-like insulator to a metal frame classically demands either perfectly polished mating surfaces or brazing heat that stresses both parts. The move here is a translator layer: a patterned metal film is laser-bonded onto the insulator first, and the metal ferrule is then conventionally welded to that film — so the fragile insulator never feels the welding heat. And because the bonding works from one side, the frame can be attached after the electronics are already in place, something brazing temperatures would never allow.

A cross-section of the ferrule assembly spanning between housing walls, paired with a top view of the racetrack-shaped frame and its three feedthrough openings. — Phosphor plate · US 11,865,639
A cross-section of the ferrule assembly spanning between housing walls, paired with a top view of the racetrack-shaped frame and its three feedthrough openings. US patent drawing — public domain.

Read the patent → The full dossier

2024 ◇ Methods for forming hermetically-sealed packages including feedthrough assemblies US 11,950,387 · sole inventor

Every implantable device needs wires to pass through a wall that must stay absolutely sealed against body fluid. This sole-inventor grant covers the methods behind that trick: a laser traces a ring around each tiny via, welding the contact down so the doorway itself is fused shut instead of brazed in a furnace. Granted in 2024, it carried a line seeded by twin provisional applications filed one Christmas Eve in 2014 into its second decade.

Laser energy fires up through the see-through substrate to weld a contact over its tiny via, leaving ring-shaped bond lines encircling the wire's passage. — Phosphor plate · US 11,950,387
Laser energy fires up through the see-through substrate to weld a contact over its tiny via, leaving ring-shaped bond lines encircling the wire's passage. US patent drawing — public domain.

Read the patent → The full dossier

2024 Electronic package and device including same US 12,082,354

A 2024 addition to the hermetic-packaging cluster: an electronic package built around shaped conductor blocks — the scalloped metal pieces at the base of the stack that carry the package's electrical connections. The drawings assemble it like a kit, layer by layer, from the covered components down to the arched blocks beneath the substrate.

Exploded view of the whole package: cover, components, window frames, and substrate stacked above the two rows of arched conductor blocks that carry the connections. — Phosphor plate · US 12,082,354
Exploded view of the whole package: cover, components, window frames, and substrate stacked above the two rows of arched conductor blocks that carry the connections. US patent drawing — public domain.

Read the patent → The full dossier

2025 Hermetic assembly and device including same US 12,233,477

Joining an insulator to a metal frame classically demands perfectly polished mating surfaces or high-temperature brazing that stresses the parts. This 2025 design laser-bonds a patterned metal layer onto the insulator first, then conventionally welds the ferrule's flange to that layer — so the fragile material never feels the welding heat, and because the bonding is one-sided, the frame can be attached after the electronics are already in place. An adapter pattern in metallurgy: one layer translating between the laser-bond world and the weld world.

Cross-section of the assembly at work: the ferrule-framed insulator plate spans the opening of the device housing, sealing the electronics and power source beneath it. — Phosphor plate · US 12,233,477
Cross-section of the assembly at work: the ferrule-framed insulator plate spans the opening of the device housing, sealing the electronics and power source beneath it. US patent drawing — public domain.

Read the patent → The full dossier

2026 Sealed package including electronic device and power source US 12,610,487

An implant's insides are full of joints — solder, adhesive, weld — and every one must stay stable for the life of the device. Here the electronics sit on a see-through substrate that is laser-sealed to the housing holding the power source, and the electrical connection between them is never bonded at all: the assembly's own geometry presses the contacts together and keeps them there. It is the newest grant in the corpus, issued April 2026, and 13 patent families already cite it.

The pill-shaped device shown whole, then pulled apart: the electronics carrier lifting away from the housing that holds the power source, with the small spring contact waiting in the far corner where the two simply press together. — Phosphor plate · US 12,610,487
The pill-shaped device shown whole, then pulled apart: the electronics carrier lifting away from the housing that holds the power source, with the small spring contact waiting in the far corner where the two simply press together. US patent drawing — public domain.

Read the patent → The full dossier

Line Two · 13 grants

Laser Materials Processing

The craft thread: putting heat exactly where the joint is and nowhere else. It opens in 2000 with a laser fired through the eye of a bonding tool to weld a ribbon without vibration, and matures into kinetically-limited diffusion bonds — sapphire fused to titanium across an interface thinner than 1000 nanometers, co-invented with Corning. These techniques are the enabling hands behind the packaging cathedral.

2002 ◆ Apparatus and method for laser welding of ribbons US 6,501,043 · sole inventor · 35 citations

Microelectronic connections were made by ultrasonic scrubbing — vibration that shook parts out of position and left weak, inconsistent bonds. Working alone, he threaded the ribbon under a bond head and fired a laser through an aperture in the tool itself: the head holds, the light joins. Thirty-five later patents cite it, and it opened a twenty-five-year arc of using focused light as a precision tool.

A cross-section of the welding apparatus, tracing the laser beam from its source, off a mirror, through a lens, and out the bond head's own aperture onto the ribbon joint. — Phosphor plate · US 6,501,043
A cross-section of the welding apparatus, tracing the laser beam from its source, off a mirror, through a lens, and out the bond head's own aperture onto the ribbon joint. US patent drawing — public domain.

Read the patent → The full dossier

2004 Apparatus and method for laser welding of ribbons US 6,717,100 · sole inventor · 38 citations

A sole-inventor continuation of the ribbon-welding patent that opened the laser-craft arc: a bond head holds a conductive ribbon in place while the laser fires through an aperture in the tool itself, so the weld forms without the vibration that used to shake delicate parts loose. The refinement went on to be cited by 38 later patents — more than the original.

Perspective and magnified views of the bonding tool, revealing the aperture bored straight through its foot — the eye the laser fires through. — Phosphor plate · US 6,717,100
Perspective and magnified views of the bonding tool, revealing the aperture bored straight through its foot — the eye the laser fires through. US patent drawing — public domain.

Read the patent → The full dossier

2011 Laser bonding tool with improved bonding accuracy US 7,872,208

Laser bonding is only as good as the tool's aim — the weld has to land exactly where the foot is pressing. This patent, with Ruben listed first, refines the bonding tool's tip so the laser strikes its target more accurately, a workhorse improvement in his laser materials-processing line. A dozen later patents cite it.

A shaded 3D close-up of the laser bonding tool's tip, with two end-on views revealing the opening in its foot. — Phosphor plate · US 7,872,208
A shaded 3D close-up of the laser bonding tool's tip, with two end-on views revealing the opening in its foot. US patent drawing — public domain.

Read the patent → The full dossier

2014 ◇ Techniques for bonding substrates using an intermediate layer US 8,796,109 · 36 citations

Some pairs of materials simply refuse to bond directly, and heating a whole stack would wreck whatever is inside. The trick here is a film just tens of nanometers thick sandwiched between the two surfaces: laser light passes clean through the top substrate and heats only that film, welding the pair right at the seam. There is even built-in quality control — the tinted film turns optically clear where the bond succeeds, so a good seal can be inspected by eye.

Three cross-section steps showing two substrates brought together over a nanometers-thin film, then fused where a laser shining through the top layer heats the film. — Phosphor plate · US 8,796,109
Three cross-section steps showing two substrates brought together over a nanometers-thin film, then fused where a laser shining through the top layer heats the film. US patent drawing — public domain.

Read the patent → The full dossier

2015 Techniques for Bonding Substrates Using an Intermediate Layer US 9,120,287

Joining two solid wafers, such as glass or silicon, without cooking the whole assembly is hard: broad heating warps parts and destroys delicate circuitry sealed inside. This method lays down a thin absorbing film between the two pieces and fires a laser straight through the transparent top substrate, so only the buried film heats up and welds the parts together exactly where the beam lands. It creates a strong, hermetic seal at room temperature everywhere else, protecting sensitive electronics inside implantable devices.

Cross-section of two stacked substrates with a thin intermediate layer between them, showing a focused laser beam passing down through the top substrate to fuse the layer at a localized bond spot. — Phosphor plate · US 9,120,287
Cross-section of two stacked substrates with a thin intermediate layer between them, showing a focused laser beam passing down through the top substrate to fuse the layer at a localized bond spot. US patent drawing — public domain.

Read the patent → The full dossier

2015 ◇ Laser assisted direct bonding US 9,171,721 · 22 citations

Conventional direct bonding fuses two polished parts by heating them past 400°C in bulk — and that heat warps and cracks the very joint it is meant to strengthen, especially between mismatched materials. This method simply presses the parts into contact to form a weak room-temperature bond, then traces a laser along the seam to strengthen it locally while everything else stays cool. It is the keystone of the corpus's laser craft — the bridge between generic direct bonding and the whole family of laser-bonded packages that followed.

A laser aimed through the tilted transparent plate at the seam where it meets the base wafer, strengthening the bond where the two touch. — Phosphor plate · US 9,171,721
A laser aimed through the tilted transparent plate at the seam where it meets the base wafer, strengthening the bond where the two touch. US patent drawing — public domain.

Read the patent → The full dossier

2017 Devices Formed With Techniques for Bonding Substrates Using an Intermediate Layer US 9,688,053

Sealing two rigid plates of glass or similar material together usually means heating the whole assembly, which can warp the parts or damage anything delicate inside. This device is bonded by laying down a thin absorbing film between the two plates and firing a laser through the top plate so only that film heats up, fusing the plates precisely where the beam lands while everything around it stays cool. The result is a strong, hermetic seal that can enclose sensitive electronics without cooking them.

Cross-section (FIGS. 1A-1C) showing a laser directing a focused beam down through the transparent top substrate onto a thin intermediate layer, which absorbs the energy and fuses the two substrates together at that spot. — Phosphor plate · US 9,688,053
Cross-section (FIGS. 1A-1C) showing a laser directing a focused beam down through the transparent top substrate onto a thin intermediate layer, which absorbs the energy and fuses the two substrates together at that spot. US patent drawing — public domain.

Read the patent → The full dossier

2018 ◆ Kinetically limited nano-scale diffusion bond structures and methods US 10,124,559 · 24 citations · with Corning

Joining sapphire to titanium — a transparent gem to an opaque metal — normally demands a furnace at 600 to 1000 °C. Invented with Corning, this technique fires a laser through the sapphire so its energy lands only at the buried interface, in a flash too brief for the heat to wander, leaving a bond thinner than 1000 nanometers between two materials that never felt an oven. The Corning co-assignment is the corpus's clearest external validation: a materials-science giant putting its name beside his.

A real electron-microscope image: undisturbed titanium on one side, undisturbed single-crystal sapphire on the other, and a bond joint only nanometers wide running between them. — Phosphor plate · US 10,124,559
A real electron-microscope image: undisturbed titanium on one side, undisturbed single-crystal sapphire on the other, and a bond joint only nanometers wide running between them. US patent drawing — public domain.

Read the patent → The full dossier

2021 Kinetically limited nano-scale diffusion bond structures and methods US 10,981,355 · with Corning

A laser pulse fired through sapphire deposits its energy exactly at the interface with the metal beneath, forming a diffusion bond thinner than a thousand nanometers. 'Kinetically limited' is the heart of it: the flash is too brief for heat to migrate, so diffusion happens only in that nano-zone and the parts never really get hot — with named applications reaching past medical packaging to vacuum windows, photonics, and spacecraft. The patent carries both Medtronic's and Corning's names — a materials-science giant's endorsement written into the record.

A laser fires its beam through a transparent sapphire sheet stacked against a metal plate, landing its energy at the hidden interface where the bond will form. — Phosphor plate · US 10,981,355
A laser fires its beam through a transparent sapphire sheet stacked against a metal plate, landing its energy at the hidden interface where the bond will form. US patent drawing — public domain.

Read the patent → The full dossier

2023 Surface texturing using energy pulses US 11,548,092

An implanted electrode wants the most surface area in the least space, but texturing metal in a gas environment can't make the features fine enough. The answer: fire the energy pulses at the metal while it sits under liquid, whose faster heat transfer quenches the melt quickly enough to freeze in texture at micro scale or smaller. The bath does double duty — its oxygen and nitrogen react with the hot metal so texture and surface chemistry arrive in the same pulse, for electrodes, stent struts, and housings.

An energy pulse strikes the metal surface, leaving a field of micro-scale peaks in its wake. — Phosphor plate · US 11,548,092
An energy pulse strikes the metal surface, leaving a field of micro-scale peaks in its wake. US patent drawing — public domain.

Read the patent → The full dossier

2024 Surface texturing using energy pulses US 11,969,821

An electrode works better the more surface it packs into a tiny footprint, and texturing in a gas environment can't make the features fine enough. The method here fires energy pulses at metal sitting under liquid: the liquid quenches the heat faster, leaving micro-scale-or-smaller texture, while its oxygen and nitrogen react with the hot metal so texture and surface chemistry form in the same pulse. A 2024 continuation of the underwater-texturing line, aimed at electrodes, stent struts, and device housings.

A focused pulse of energy strikes the metal, shown in cross-section with the rows of tiny peaks it raises across the surface. — Phosphor plate · US 11,969,821
A focused pulse of energy strikes the metal, shown in cross-section with the rows of tiny peaks it raises across the surface. US patent drawing — public domain.

Read the patent → The full dossier

2024 Laser cutting system US 11,999,014

Laser-cutting a board with buried conductors has a hidden failure mode: the cut smears conductive residue across the exposed face, leaving invisible paths for leakage. This system cuts with one beam and follows with a second, angled to clean the cut surface — and it watches for the plasma flash when the first beam strikes metal, using that flash to locate the conductor and aim the cleanup beam automatically. Late-career work, granted 2024: even the cutting step gets closed-loop intelligence.

Schematic of the two-beam station: the first beam (dashed) slices down through the workpiece, then a mirror redirects the second beam at a controlled angle so it sweeps the freshly cut face. — Phosphor plate · US 11,999,014
Schematic of the two-beam station: the first beam (dashed) slices down through the workpiece, then a mirror redirects the second beam at a controlled angle so it sweeps the freshly cut face. US patent drawing — public domain.

Read the patent → The full dossier

2025 Kinetically limited nano-scale diffusion bond structures and methods US 12,454,117 · with Corning

This is the 2025 form of the diffusion-bond line David shares with glassmaker Corning — one of the few places in the corpus where another company's name sits beside Medtronic's on the patent itself. A laser fires through a transparent material into the buried face where it meets metal, forming a kinetically limited bond only nanometers deep while the bulk of both materials stays cool and undisturbed. The line has drawn 34 citing patent families.

The whole setup in one glance: a laser aims its beam at a face-to-face stack of a transparent sheet and a metal plate, landing at the hidden seam between them. — Phosphor plate · US 12,454,117
The whole setup in one glance: a laser aims its beam at a face-to-face stack of a transparent sheet and a metal plate, landing at the hidden seam between them. US patent drawing — public domain.

Read the patent → The full dossier

Line Three · 9 grants

Implantable Sensors

A therapy device is blind without senses. This cluster gives implants their proprioception: shock-proof piezoelectric accelerometers that let pacemakers feel a patient's motion and pace the heart to match (the verified rate-responsive lineage), capacitive pressure sensors robust to parasitic effects, and — in the pending pipeline — multi-analyte biosensor arrays. The arc runs from feeling motion to reading blood chemistry.

1999 ◆ Shock resistant accelerometer for implantable medical device US 5,885,471 · 203 citations

A rate-responsive pacemaker senses its patient's activity through a tiny piezoelectric beam — a diving board that generates voltage as it flexes — but early beams were so fragile that dropping the device from a few feet could snap them. This invention adds a stop that leaves normal flexing untouched yet catches the beam just before a shock would break it. It is the most-cited patent in the corpus, with over 200 later patents building on it.

The shock-stop sensor in exploded stack, end-on cross-section, and assembled form — the piezoelectric beam caught between grooved plates whose center rails arrest it before a jolt can snap it. — Phosphor plate · US 5,885,471
The shock-stop sensor in exploded stack, end-on cross-section, and assembled form — the piezoelectric beam caught between grooved plates whose center rails arrest it before a jolt can snap it. US patent drawing — public domain.

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1999 High output sensor and accelerometer implantable medical device US 5,911,738 · 105 citations

Part of the line that taught pacemakers to feel motion: a piezoelectric sensing element, built with James M. Sikorski, engineered to deliver a stronger electrical signal as it flexes with the body's movement — a clearer read on patient activity for rate-responsive pacing. With 105 citing patents, it ranks among the most-cited work in the corpus.

An exploded perspective of the sensor assembly: the piezoelectric plate, diced from a scored wafer, seated into the clamped stack that holds it. — Phosphor plate · US 5,911,738
An exploded perspective of the sensor assembly: the piezoelectric plate, diced from a scored wafer, seated into the clamped stack that holds it. US patent drawing — public domain.

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2000 High output sensor and accelerometer for implantable medical device US 6,038,475 · 85 citations

The second of two grants with James M. Sikorski refining the accelerometer line's high-output sensing element — the piezoelectric beam whose flexing with body motion tells a pacemaker its patient is up and active. A continuation that sharpened the earlier design, it has been cited by 85 later patents.

Side views of the sensing beam with its layered and segmented electrodes, ending in a small circuit sketch of the two capacitor sections the element forms. — Phosphor plate · US 6,038,475
Side views of the sensing beam with its layered and segmented electrodes, ending in a small circuit sketch of the two capacitor sections the element forms. US patent drawing — public domain.

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2001 ◆ Accelerometer for implantable medical device US 6,216,537 · 131 citations

A motion-sensing beam measures along only one axis — and the axis that matters clinically points into and out of the patient's chest, while sensors naturally lie flat on the circuit board, aiming the wrong way. This surface-mount package uses multilayer conductive end caps to stand the sensing element upright, pointing its sensitivity where medicine needs it while staying mass-producible and testable. More than 130 later patents cite the solution.

The assembled sensor block beside an exploded view that pops it open, revealing the tiny piezoelectric beam suspended over its cavity between two covers. — Phosphor plate · US 6,216,537
The assembled sensor block beside an exploded view that pops it open, revealing the tiny piezoelectric beam suspended over its cavity between two covers. US patent drawing — public domain.

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2009 Pressure sensor configurations for implantable medical electrical leads US 7,591,185

A cardiac lead is normally just wiring; this patent puts a working pressure sensor inside the lead itself. Behind an insulating sidewall, a pressure-sensitive diaphragm moves one plate of a tiny gap capacitor read by an on-board chip, with a grounded conductive layer shielding the measurement. It is the moment the wire becomes an instrument.

An exploded view of the sensor module: the block-shaped pressure sensor with its diaphragm window floating between its cradle and the lead's outer tube with a matching cutout. — Phosphor plate · US 7,591,185
An exploded view of the sensor module: the block-shaped pressure sensor with its diaphragm window floating between its cradle and the lead's outer tube with a matching cutout. US patent drawing — public domain.

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2011 Pressure sensor configurations for implantable medical electrical leads US 7,886,608

A cardiac lead is normally just a wire; this work builds a pressure sensor directly into it, so the wire itself becomes an instrument. Inside the lead's insulating wall, a pressure-sensitive diaphragm forms one plate of a gap capacitor read by an integrated circuit, with a grounded conductive layer shielding the diaphragm from interference. It's a continuation in a sensing line whose ideas were picked up by 46 later patent families.

The full implantable lead, from its connector pins down to the inline pressure-sensor capsule near the tip. — Phosphor plate · US 7,886,608
The full implantable lead, from its connector pins down to the inline pressure-sensor capsule near the tip. US patent drawing — public domain.

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2013 ◇ Implantable capacitive pressure sensor apparatus and methods regarding same US 8,424,388

Tiny capacitive pressure sensors are haunted by stray capacitance, and the problem is worst exactly where implants live — surrounded by conductive tissue and fluid. This design flips the obvious layout: the electrode facing the body is the grounded, pressure-flexing diaphragm, while the signal electrode sits isolated on an insulator behind it, so the patient's own conductivity becomes shielding instead of interference. Design judo — the hostile environment is recruited into the circuit.

An exploded view of the pressure-sensor module and the tubular housing halves that carry it inside an implantable lead. — Phosphor plate · US 8,424,388
An exploded view of the pressure-sensor module and the tubular housing halves that carry it inside an implantable lead. US patent drawing — public domain.

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2017 Media-exposed interconnects for transducers US 9,616,223

Some sensor connections cannot hide behind a hermetic wall — the strain of a beating heart is too much for sealed designs — yet bare connections corrode. This one stacks two conductive layers whose stresses pull in opposite directions, one compressive and one tensile, cancelling to almost no net load, and builds the contacts from valve metals like titanium whose surface oxide resists corrosion in saline. Filed in 2005 and granted twelve years later, it is cited by Endotronix, the company behind an implantable heart-failure pressure sensor.

Cross-section of the exposed connection: layered metal draped over the sensor contact, built to face body fluids directly. — Phosphor plate · US 9,616,223
Cross-section of the exposed connection: layered metal draped over the sensor contact, built to face body fluids directly. US patent drawing — public domain.

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2023 Pressure sensor assembly for use in implantable medical device (substrate with via along via axis) US 11,725,995

Shrink a capacitive pressure sensor far enough and its signal drowns — stray capacitance and manufacturing variation swamp the tiny reading, and protective films only add stress. The fix removes the middleman: the flexing membrane carries one capacitor plate while the second sits on the integrated circuit itself, so the sensing capacitor forms straight along the axis of a via. The membrane can even be part of the enclosure — the sensor's own package becomes the sensing element.

A cross-section of the sensor assembly: the flexible membrane spans the substrate via, forming the pressure-sensing gap directly against the circuitry below. — Phosphor plate · US 11,725,995
A cross-section of the sensor assembly: the flexible membrane spans the substrate via, forming the pressure-sensing gap directly against the circuitry below. US patent drawing — public domain.

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Line Four · 9 grants

Power Sources

Every battery change is a surgery. This cluster attacks that arithmetic from every direction — wafer-scale packages with power sealed inside, stacked thin-film battery fabrication, and the boldest line: nuclear micro-power. Medtronic implanted plutonium pacemakers in 1970; one ran 34 years. David's 3D nanostructured betavoltaic converters are that dream rebuilt with quantum dots and metal foam — a radiation sponge in place of a thermal slug.

2014 ◆ Wafer-scale package including power source US 8,666,505 · 50 citations

Direct wafer bonding runs hot enough to destroy a battery — yet a device isn't truly complete at wafer scale until its power source is sealed inside. This design puts the control chip and the battery together in a cavity between two bonded substrates, then closes the seam with low-temperature laser-assisted bonding so nothing inside is harmed. It became one of the most-cited pieces of work in the corpus, with 126 later patent families drawing on it as tiny self-powered leadless implants became an industry.

Four cross-section stills of the build: the wired base, the chip soldered on, the flat battery lowered onto its pads, and the recessed lid descending to seal both inside one cavity. — Phosphor plate · US 8,666,505
Four cross-section stills of the build: the wired base, the chip soldered on, the flat battery lowered onto its pads, and the recessed lid descending to seal both inside one cavity. US patent drawing — public domain.

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2016 ◇ Power sources suitable for use in implantable medical devices and corresponding fabrication methods US 9,252,415

A single thin-film battery cell is only about 14 microns thick — far too little energy on its own to power an implant. So the cells are made like chips, in arrays on wafers, then stacked: routing layers carry each cell's contacts out to the side, vias gang the aligned contacts in parallel, and micron-scale cavities engineered between the cells give them room to swell as they charge. IBM and France's atomic-energy agency are among the citing parties — battery stacking with relevance well beyond medicine.

Battery cells arrayed on a wafer with the routing layer hovering above them, and the finished multi-layer stack they become. — Phosphor plate · US 9,252,415
Battery cells arrayed on a wafer with the routing layer hovering above them, and the finished multi-layer stack they become. US patent drawing — public domain.

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2016 ◆ Wafer-scale package including power source US 9,318,400

Fusing two wafers into one sealed package normally takes 400°C or more — heat that would destroy any battery inside — yet a device is not truly wafer-scale-complete without its power source built in. This design encloses both the control chip and its battery in a cavity between two bonded substrates, hermetically sealed by low-temperature laser-assisted bonding, and explicitly contemplates leadless device configurations. With 151 later patent families citing it, it is the most-cited grant in the corpus.

Four-step assembly sequence: a wired glass wafer, the chip lowered on, the battery lowered on, and a second wafer descending to seal both inside. — Phosphor plate · US 9,318,400
Four-step assembly sequence: a wired glass wafer, the chip lowered on, the battery lowered on, and a second wafer descending to seal both inside. US patent drawing — public domain.

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2016 Wafer-Scale Package Including Power Source US 9,431,312

An implantable medical device has to be tiny, sealed tight against the body, and carry its own power — usually meaning a bulky separate battery and housing. This design instead builds the whole thing at wafer scale: a control chip and a thin-film energy-storage device are mounted on one substrate, then a second substrate is bonded over them to seal both inside a single hermetic cavity. The result is a self-powered sensing-and-stimulation package small enough to go where earlier electronics-plus-battery assemblies could not.

Cross-sectional view (FIG. 1) of the wafer-scale package: two bonded substrates form a sealed cavity holding both the control-module die and the energy-storage device that powers it, with conductive vias and traces routing signals through the walls. — Phosphor plate · US 9,431,312
Cross-sectional view (FIG. 1) of the wafer-scale package: two bonded substrates form a sealed cavity holding both the control-module die and the energy-storage device that powers it, with conductive vias and traces routing signals through the walls. US patent drawing — public domain.

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2018 ◆ Nuclear radiation particle power converter US 10,096,393

A betavoltaic cell works like a solar panel lit by radiation instead of sunlight — but a flat panel lets much of each particle's energy slip away before it is collected. This design crumples the collector into a three-dimensional sponge of coated nanostructures, so nearly every particle strikes a working junction before its charge can fade. It founded the patent line reconnecting Medtronic to its nuclear-pacemaker heritage: the pursuit of an implant whose power source never needs replacing.

Cross-section of the betavoltaic cell: a sponge-like tangle of coated nanostructures filling the gap between two flat electrode plates. — Phosphor plate · US 10,096,393
Cross-section of the betavoltaic cell: a sponge-like tangle of coated nanostructures filling the gap between two flat electrode plates. US patent drawing — public domain.

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2020 Nuclear radiation particle power converter US 10,811,157

A flat radiation-to-electricity converter wastes much of what its fuel emits: charge carriers recombine before they can be collected. This continuation carries the 3D answer forward — a sponge-like collector of nanorods, nanotubes, or foam, coated with charge-separating layers such as quantum dots, with the isotope infiltrated into the structure itself, even by exposing the finished sponge to pressurized tritium gas. It is a solar cell rebuilt around beta decay, with the fuel soaked into the electrode.

A cross-section of the sponge-like 3D collector — a tangle of coated nanostructures filling the gap between two flat electrode plates. — Phosphor plate · US 10,811,157
A cross-section of the sponge-like 3D collector — a tangle of coated nanostructures filling the gap between two flat electrode plates. US patent drawing — public domain.

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2020 ◇ Power source and method of forming same (radioluminescent: radioactive to light to photovoltaic) US 10,818,811

Instead of converting radiation straight to electricity, this power source takes a detour through light: a hermetically sealed cavity holds radioactive material beside a phosphor that glows under its particles, and a photovoltaic layer harvests the glow. The design even accounts for the helium that tritium decay produces, using a gas-permeable substrate so the sealed cavity doesn't slowly pressurize itself over the decades — a battery designed around its own exhaust. It founded the radioluminescent branch of the corpus's nuclear-power line.

A cross-section mid-glow: rays of light criss-cross from the embedded particles to the energy-harvesting layers above and below. — Phosphor plate · US 10,818,811
A cross-section mid-glow: rays of light criss-cross from the embedded particles to the energy-harvesting layers above and below. US patent drawing — public domain.

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2021 Power source and method of forming same US 11,189,390

A nuclear battery is only as good as its fuel storage, and tritium — a workhorse isotope — is a gas, which limits how much power can be packed into a small space. The answer here is a loaded substrate: a carrier material holds the isotope densely, thin deposited barrier layers keep it from wandering, and the whole assembly sits inside a sealed enclosure. Contain the fuel properly, and the rest of the battery can do its job.

Cross-sections of the sealed power source: the isotope-bearing layer at the floor of its housing, and a variant packed with granular carrier material beneath the cover. — Phosphor plate · US 11,189,390
Cross-sections of the sealed power source: the isotope-bearing layer at the floor of its housing, and a variant packed with granular carrier material beneath the cover. US patent drawing — public domain.

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2024 ◇ Nuclear radiation particle power converter US 11,881,325

A radioisotope is a battery whose lifetime is set by nuclear physics rather than chemistry — the only power source that can promise decades of output sealed inside a body. This grant is the latest and broadest form of the converter: a three-dimensional current collector coated with charge-separating layers, with the radiation-emitting fuel placed so its particles strike inside the sponge rather than a flat panel. It issued in January 2024, just as nuclear microbatteries were making startup headlines, on work with priority stretching back to 2014.

A cross-section of the converter: a sponge-like three-dimensional collector, traced with thin coating layers, filling the gap between two flat electrode plates. — Phosphor plate · US 11,881,325
A cross-section of the converter: a sponge-like three-dimensional collector, traced with thin coating layers, filling the gap between two flat electrode plates. US patent drawing — public domain.

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Line Five · 3 grants

The smallest cluster carries the heaviest human stakes: MEMS-actuated shunt valves for hydrocephalus — closed-loop pressure control for a condition where device failure often means brain surgery, frequently a child's — plus accelerometer-corrected magnetic tracking for surgical navigation. Engineering applied where the margin for error is a person.

2018 ◇ Error correction techniques in surgical navigation US 9,913,693

Magnetic tracking pinpoints a surgical instrument faster than the patient can be re-imaged, so every heartbeat and breath shifts the anatomy and leaves the instrument drawn in the wrong place on a frozen picture. The fix pairs the magnetic sensor with an accelerometer: when acceleration spikes, the system falls back on trusted earlier positions, and frequency analysis can even tell a heartbeat from a breath from the surgeon's own hand. It is his accelerometer craft resurfacing thirteen years later in the operating room, now cited by 145 later patent families.

Two angiogram images from the patent itself, a crosshair marking the tracked instrument's position on the heart. — Phosphor plate · US 9,913,693
Two angiogram images from the patent itself, a crosshair marking the tracked instrument's position on the heart. US patent drawing — public domain.

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2023 ◆ System and method for valve control US 11,701,503

For a person with hydrocephalus, an implanted shunt valve quietly decides how much cerebrospinal fluid drains from the brain — the heaviest human stakes anywhere in the corpus. This valve is not a simple spring but a layered machine: tiny MEMS actuators flex a membrane to tune the opening, while a pressure sensor reports back so the implanted controller keeps adjusting until measured flow matches the doctor's target. The settings arrive wirelessly from a handheld programmer outside the body.

The valve assembly pulled apart into its stack: inlet dome with its ball-and-cone seat, the flexible membrane, the plate of MEMS actuators and electronics, and the fluid reservoir base. — Phosphor plate · US 11,701,503
The valve assembly pulled apart into its stack: inlet dome with its ball-and-cone seat, the flexible membrane, the plate of MEMS actuators and electronics, and the fluid reservoir base. US patent drawing — public domain.

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2024 System and method for valve control US 12,059,542

In hydrocephalus, excess fluid must drain from the brain through an implanted shunt — and the valve doing that job has to hold exactly the right pressure. This grant continues the closed-loop valve line: a MEMS micro-machine inside the flow-control assembly adjusts the valve according to the selected pressure settings. It belongs to the family the exhibit ranks as carrying the heaviest human stakes in the corpus.

Exploded view of the valve assembly: the inlet dome with its ball-and-cone seat on top, the cross-hatched flexible membrane beneath it, the plate of micro-actuators and electronics below, and the fluid reservoir at the base. — Phosphor plate · US 12,059,542
Exploded view of the valve assembly: the inlet dome with its ball-and-cone seat on top, the cross-hatched flexible membrane beneath it, the plate of micro-actuators and electronics below, and the fluid reservoir at the base. US patent drawing — public domain.

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Line Six · 5 grants

Interconnects & Materials

The quiet cluster: corrosion-resistant contact stacks using titanium-niobium, metallization with deliberately tailored (even negative) thermal expansion so joints don't tear themselves apart across temperature swings, freeform substrates cut to the device's interior shape, and terminal arrays that replaced hand-wiring. Nearly all sole-inventor work — the personal toolbox underneath everything else.

2004 ◇ Freeform substrates and devices US 6,787,891 · sole inventor

Substrates come out rectangular because saws cut straight — but implantable devices are curved, so corners of precious interior volume sit empty. Ruben's sole-inventor answer, filed in 2000, was to cut the silicon freeform to the device's interior contour using a water-jet-guided laser, shaping the circuitry to match. Every reclaimed cubic millimeter is that much less bulge in a patient's chest.

Three perspective views of a substrate cut and curved to hug a device's rounded interior, its chip pads riding the bend. — Phosphor plate · US 6,787,891
Three perspective views of a substrate cut and curved to hug a device's rounded interior, its chip pads riding the bend. US patent drawing — public domain.

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2005 ◆ Implantable medical device including a surface-mount terminal array US 6,963,780 · 67 citations

Welding and wire-bonding straight onto a circuit board kept damaging the board itself: solder contamination, heat cracking, costly rework. This molded terminal array is a translation layer — each terminal offers a small solder face downward for tight-pitch fillets and a large bond head upward for the bonding tools, so each joining technology gets the surface it wants. Rivals noticed: the patent has been cited roughly 31 times by effectively the whole competing pacemaker-and-neurostimulator industry, from Boston Scientific and BIOTRONIK to Verily and TDK.

A 3D view of the molded terminal block with its buried terminals, beside a cross-section of one terminal — narrow solder face below, wide wire-bond head above. — Phosphor plate · US 6,963,780
A 3D view of the molded terminal block with its buried terminals, beside a cross-section of one terminal — narrow solder face below, wide wire-bond head above. US patent drawing — public domain.

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2008 Freeform substrates and devices US 7,335,530 · sole inventor

A continuation of Ruben's sole-inventor freeform-substrates idea: instead of a rectangular circuit board leaving the corners of a curved implantable device empty, the substrate is cut to the shape of the device's interior. Even the integrated-circuit components are formed to follow that contour, freeing room for more electronics — or letting the whole device shrink.

A view into a pill-shaped device where the circuit components fan around the rounded end instead of stopping at a rectangle's corner. — Phosphor plate · US 7,335,530
A view into a pill-shaped device where the circuit components fan around the rounded end instead of stopping at a rectangle's corner. US patent drawing — public domain.

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2012 ◇ Metallization with tailorable coefficient of thermal expansion US 8,141,556 · sole inventor

Welding a wire to a thick metal pad on silicon can crack the chip, because the heat makes pad and substrate expand at different rates. The sole-inventor answer is a composite pad containing a material that shrinks when heated — niobium and niobium pentoxide, blended so the mismatch cancels to zero — and the patent hands over the design equation as a recipe. The idea traveled: four of its visible citations come from Lockheed Martin, defense-aerospace uptake of an implant metallurgy trick.

A cross-section of a connector ribbon welded onto the layered pad whose composite metal is tuned to expand in step with the substrate below. — Phosphor plate · US 8,141,556
A cross-section of a connector ribbon welded onto the layered pad whose composite metal is tuned to expand in step with the substrate below. US patent drawing — public domain.

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2013 ◇ Layered structure for corrosion resistant interconnect contacts US 8,461,681 · sole inventor

Electrical contacts that sit in blood corrode, slowly degrading an implanted sensor over the years it must survive. This sole-inventor design armors them in a three-layer sandwich — titanium-niobium, niobium, titanium-niobium again — chosen for corrosion resistance and for thermal expansion that can be tuned to match the silicon beneath. It was filed the same day as its twin, the negative-expansion weld pad, as two complementary answers to the slow thermal-mechanical death of interconnects.

A cutaway perspective of the sensor capsule built into an implantable lead, exposing the interconnect contacts the layered coating is designed to protect. — Phosphor plate · US 8,461,681
A cutaway perspective of the sensor capsule built into an implantable lead, exposing the interconnect contacts the layered coating is designed to protect. US patent drawing — public domain.

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