Massachusetts Institute of Technology

Other

Steven W Rabe

Carl O Bozler

Dale C Flanders

Peter S Whitney

Christopher W Leitz

Mark Alexander Hollis

Brian F Aull

Kirby B Nichols

Jeremy Bert Muldavin

Craig L Keast

Michael John Tobias

David Volfson

Daniel R Schuette

Kevin Ryu

Renee D Lambert

Peter W Wyatt

Joseph S Ciampi

Karl Alexander McIntosh

Christopher T Harris

A chip-to-chip integration process for rapid prototyping of silicon avalanche photodiode (APD) arrays has been developed. This process has several advantages over wafer-level 3D integration, including: (1) reduced cost per development cycle since a dedicated full-wafer read-out integrated circuit (ROIC) fabrication is not needed, (2) compatibility with ROICs made in previous fabrication runs, and (3) accelerated schedule. The process provides several advantages over previous processes for chip-to-chip integration, including: (1) shorter processing time as the chips can be diced, bump-bonded, and then thinned at the chip-level faster than in a wafer-level back-illumination process, and (2) the CMOS substrate provides mechanical support for the APD device, allowing integration of fast microlenses directly on the APD back surface. This approach yields APDs with low dark count rates (DCRs) and higher radiation tolerance for harsh environments and can be extended to large arrays of APDs.

Rapid prototyping of single-photon-sensitive silicon avalanche photodiodes

A device includes a device wafer having a circuit component formed thereon and having vias formed therein and a cap wafer bonded to the device wafer. The cap wafer has a cavity therein. The cavity has a post formed therein, and the post is positioned to mechanically support the vias formed in the device wafer. The cavity has a volume, the volume substantially enclosing the circuit component formed on the device wafer. The cavity has a width and height such that an impedance of a transmission line is dependent upon the width and height of the cavity, or the impedance of a transmission line is dependent upon the width of a center conductor within the cavity.

Wide band and radio frequency waveguide and hybrid integration in a silicon package

An optical switch device includes a rolling shutter or membrane attached at one of its edges to a substrate near an optical port in the substrate. The rolling shutter can assume one of two states. In a first closed state, the membrane is uncoiled onto the substrate over the port such that light directed at the port impinges on the shutter. In a second open state, the membrane is rolled up away from the port such that light directed at the port impinges on the port. In one embodiment, a mirror is formed on the membrane such that when the membrane is in the closed state over the substrate, light directed at the port is reflected by the mirror. In one configuration, the optical port includes a hole or aperture such light passed through the port without interference. The device can include a latch electrode the far end of the membrane such that when it is rolled out, it can be held in position by a latching voltage applied across the latch electrode and the substrate. Slits can be formed in the membrane to keep the mirror flat by relieving strain in the membrane and to allow gases in proximity to the device to pass through the membrane as it is activated. The shutter can include dimples to minimize the area of contact between the membrane and the substrate to reduce the probability of the two sticking together. The attachment edge of the membrane can be made shorter than its width to reduce distortions in the membrane to keep the mirror flat. A raised annular rim can be provided around the port such that when the shutter is held down over the port it is pulled taut and flat over the rim. This feature is also used to maintain flatness in the mirror. The switch device can be used as part of an array of optical switches.

Rolling shutter optical switch device with latch electrode and slits in shutter

Rolling shutter optical switch device with dimples on shutter, annular rim at optical port and shortened shutter attachment edge

A spatial light modulator formed of a moveable electrode which is disposed opposite a fixed electrode and is biased to roll in a preferred direction upon application of an electric field across the electrodes to produce a light valve or light shutter. In one embodiment, the moveable electrode is restrained at one end and coils about the fixed end in a preferential roll direction. The bias is achieved by inducing anisotropic stress or anisotropic stiffness.

Spatial light modulator

A method for improving the sound producing ability of musical instruments by securing at least some components of the instrument to a supporting surface and then vibrating the surface at various frequencies across a broad bandwidth for an optimal time. This method may be applied to partially assembled instruments during the manufacturing process, to completed instruments with strings and/or hardware removed, and to fully assembled new and old instruments.

Acoustic response of components of musical instruments

A bistable electrostatic light valve display in which a movable electrode is disposed opposite a fixed electrode and is biased to move in a preferred direction upon application of an electric field across the electrodes to produce a light valve or light shutter. In one embodiment, the movable electrode is restrained at one end and coils about the fixed end in a preferential roll direction. The bias is achieved by inducing anisotropic stress or anisotropic stiffness. In another embodiment, the moveable electrode is restrained at both ends and is biased upwardly by anisotropic stress or stiffening.

Electric display device

The base layer of a power permeable base transistor is formed as comb structures with grating teeth of the combs extending into active regions of semiconductor material. Extended active regions are separated by inactive regions over which collector contacts extend. Large devices have digitated base layers. The comb structures are fabricated by sputtering a uniform layer of tungsten and forming a nickel mask over the tungsten by both X-ray and photolithography techniques. The tungsten exposed by the nickel mask is then etched to leave the comb structures.

Permeable base transistor having an electrode configuration for heat

Growing community of inventors

Glendale, CA, United States of America

Steven W Rabe