Massachusetts Institute of Technology

Candescent Technologies Corporation

USA As Represented by Secretary of the Navy

Advanced Technology Materials, Inc.

Silicon Video, Inc.

Michael W Geis

Jonathan C Twichell

Theodore M Lyszczarz

Henry Ignatius Smith

John M Macaulay

Stephanie A Gajar

John C Fan

Bor-Yeu Tsaur

Nancy Geis

Dale C Flanders

Harry A Atwater

Steven Jay Spector

Robert M Duboc

Christopher J Curtin

Joshua Kramer

Mankuan Michael Vai

Matthew E Grein

Joseph Varghese

Donna M Lennon

Nickolay N Efremow

Marc J Burke

Jeehwan Kim

Dirk Robert Englund

George R Brandes

Franz Xaver Kaertner

Daniel J Ehrlich

Mark Alexander Hollis

Theodore H Fedynyshyn

Roderick Russell Kunz

Timothy Grotjohn

Robert Wright, Jr

Mordechai Rothschild

Dimitri A Antoniadis

James E Butler

Elliott R Brown

Margaret B Stern

Robert Nemanich

Carl V Thompson

Richard J Molnar

Stephen J Eglash

Stella W Pang

Fuwan Gan

Donald D Flechtner

Travis Wade

Yoon Jung

Daniel L Smythe

Christopher L Dennis

Kevin E Krohn

Robert T Schulein

Karen M G V Gettings

Nickolai N Efremow

Jung U Yoon

George E Brandes

Nikolay N Efremow

Sandra J Deneault

Keith E Krohn

Karen Mgv Gettings

Michael F Marchant

An improved waveguide is disclosed. The waveguide utilizes a luminescent material disposed within or around its perimeter to introduce additional light into the waveguide. For example, the waveguide may include a plurality of planar layers having different refractive indexes. A luminescent material may be disposed along the outer edge of these layers. When light from within the waveguide strikes the luminescent material, it emits light, thereby adding to the light in the waveguide. Not only does the luminescent material introduce more light into the waveguide, it also introduces more light sources, thereby making it more difficult to introduce a probe without blocking at least a portion of the light destined for the image sensor. The luminescent material may be a phosphor.

Phosphor-loaded waveguide

In some embodiments, a semiconductor structure can include: a diamond substrate having a surface conductive layer; a heavily doped region formed in the diamond substrate; and a metal contact positioned over the conductive surface layer such that a first portion of the heavily doped region is covered by the metal contact and a second portion of the heavily doped region is not covered by the metal contact.

Distributed current low-resistance diamond ohmic contacts

According to some embodiments, a method for stabilizing electrical properties of a diamond semiconductor comprises terminating a surface of a diamond with hydrogen (H) or deuterium (D) atoms and over-coating the surface of the diamond with an encapsulating material comprising metal oxide salt doped with one or more elements capable of generating negative charge in the metal oxide salt.

Doped encapsulation material for diamond semiconductors

A buffer layer is employed to fabricate diamond membranes and allow reuse of diamond substrates. In this approach, diamond membranes are fabricated on the buffer layer, which in turn is disposed on a diamond substrate that is lattice-matched to the diamond membrane. The weak bonding between the buffer layer and the diamond substrate allows ready release of the fabricated diamond membrane. The released diamond membrane is transferred to another substrate to fabricate diamond devices, while the diamond substrate is reused for another fabrication.

Systems and methods for fabricating single-crystalline diamond membranes

Method and apparatus for modulation of both the intensity and the polarization of radiation in silicon waveguides by applying a biasing voltage to the waveguide.

Method and apparatus for modulation using a conductive waveguide

A Silicon photodetector contains an insulating substrate having a top surface and a bottom surface. A Silicon layer is located on the top surface of the insulating substrate, where the Silicon layer contains a center region, the center region being larger in thickness than the rest of the Silicon layer. A top Silicon dioxide layer is located on a top surface of the center region. A left wing of the center region and a right wing of the center region are doped. The Silicon photodetector also has an active region located within the center region, where the active region contains a tailored crystal defect-impurity combination and Oxygen atoms.

System and method for providing a high frequency response silicon photodetector

A surface-emission cathode formed on an insulating surface having cantilevered, i.e. 'undercut,' electrodes. Suitable insulating surfaces include negative electron affinity (NEA) insulators such as glass or diamond. The cathode can operate in a comprised vacuum (e.g., 10Torr) with no bias on the electrodes and low vacuum electric fields (e.g., at least 10 V cm). Embodiments of the present invention are inexpensive to fabricate, requiring lithographic resolution of approximately 10 micrometers. These cathodes can be formed over large areas for use in lighting and displays and are suitable for satellite applications, such as cathodes for tethers, thrusters and space-charging neutralizers.

Surface-emission cathodes having cantilevered electrodes

A method of making a Schottky diode comprising the steps of: providing a single crystal diamond comprising a surface; placing the single crystal diamond in a CVD system; heating the diamond to a temperature of at least about 950&deg; C.; providing a gas mixture capable of growing diamond film and comprising a sulfur compound through the CVD system; growing an epitaxial diamond film on the surface of the single crystal diamond; baking the diamond at a temperature of at least about 650&deg; C. in air for a period of time that minimizes oxidation of the diamond; and fabricating a Schottky diode comprising the diamond film. A Schottky diode comprising an epitaxial diamond film and capable of blocking at least about 6 kV in a distance of no more than about 300 &mgr;m.

Method of manufacturing high voltage schottky diamond diodes with low boron doping

The method and apparatus of the invention create a dynamic Soret effect for propelling a target chemical constituent along a pathway. A moving temperature profile impressed upon the pathway produces consecutive alternating warmer and cooler zones along the path which transport components of a mixture down the path according to their respective diffusivities. In one embodiment, the invention provides a dynamic thermophoretic concentrator for separating a target chemical constituent from a mixture of components on the basis of diffusion coefficient by using alternate forward and backward motion of a temperature profile along the pathway, thereby accumulating an ultimate concentration of the target constituent greater than its initial concentration in the mixture.

Thermophoretic pump and concentrator

Improved field-emission devices are based on composing the back contact to the emitter material such that electron-injection efficiency into the emitter material is enhanced. Alteration of the emitter material structure near the contact or geometric field enhancement due to contact morphology gives rise to the improved injection efficiency. The devices are able to emit electrons at high current density and lower applied potential differences and temperatures than previously achieved. Wide-bandgap emitter materials without shallow donors benefit from this approach. The emission characteristics of diamond substitutionally doped with nitrogen, having a favorable emitter/vacuum band structure but being limited by the efficiency of electron injection into it, show especial improvement in the context of the invention. The injection-enhancing contacts can be created by combining the emitter material with an appropriate metal compound and annealing or by conventional dry anisotropic etching or ion bombardment techniques.

Field emmitters of wide-bandgap materials

The surface-emission cathodes of the invention are constructed so that the cathode body has a free surface over which electrons are efficiently accelerated after injection from a conductive contact. The junction between the free surface and the contact has the property that the height of the barrier to tunneling from the contact to floating surface states associated with the free surface of the cathode body is lower than both the barrier to emission from the contact to vacuum and the barrier to injection from the contact into the conduction band of the cathode body material. Thus under an applied potential, electrons are injected from the contact into floating surface states associated with the free surface. After acceleration, electrons leave the free surface, either emitted to vacuum or injected into another medium.

Surface-emission cathodes

Fabrication of an electron-emitting device entails distributing electron-emissive carbon-containing particles (22) over a non-insulating region (12). The particles can be made electron emissive after the particle distributing step. Particle bonding material (24) is typically provided to bond the particles to the non-insulating region. The particle bonding material can include carbide formed by heating or/and can be created by modifying a layer (32) provided between the non-insulating region and the particles. In one embodiment, the particles emit electrons primarily from graphite or/and amorphous carbon regions. In another embodiment, the particles are made electron-emissive prior to the particle distributing step.

Structure and fabrication of electron-emitting devices utilizing

Resonant-tunneling transmission lines in the various architectures rely on discrete or continuous resonant-tunneling heterostructures to actively modify propagating logic signals. One embodiment utilizes amplification of logic signals to counteract ubiquitous losses and distortion associated with any transmission medium. Basically, the logic signal is incrementally reamplified and reshaped as it propagates along the transmission line. Another embodiment is directed to a clocking system that transmits a signal represented by a sinusoid. Then, in proximity to the logic gates or modules, the sinusoid is converted into a square wave that actually clocks the gates and other logic structures. The inventive active transmission line naturally performs this feature, thus enabling clock signal transmission over longer links coupled with sinusoid-to-square wave conversion in a limited area. Still other embodiments implement step or continuous variations in the physical width of the resonant-tunneling transmission line. By manipulating the transmission line width of successive sections of the line, isolation in addition to the logic operation of the input signals is achievable in a simple monolithic circuit design. Further embodiments are directed to oscillator circuits and the control of the characteristics of the generated periodic signal.

Resonant-tunneling transmission line technology

An energetic-electron emitter providing electrons having kinetic energies on the order of one thousand electron volts without acceleration through vacuum. An average electric field of 10.sup.5 V/m to 10.sup.10 V/m applied across a layer of emissive cathode material accelerates electrons inside the layer. The cathode material is a high-dielectric strength, rigid-structure, wide-bandgap semiconductors, especially type Ib diamond. A light-emitting device incorporates the energetic-electron emitter as a source of excitation to luminescence.

Energetic-electron emitters

Growing community of inventors

Acton, MA, United States of America

Michael W Geis