University of Illinois

Richard Chan

Milton Feng

Nick Holonyak, Jr

Gabriel Walter

Shyh-Chiang Shen

David Becher

A semiconductor light-emitting transistor device, including: a bipolar pnp transistor structure having a p-type collector, an n-type base, and a p-type emitter; a first tunnel junction coupled with the collector, and a second tunnel junction coupled with the emitter; and a collector contact coupled with the first tunnel junction, an emitter contact coupled with the second tunnel junction, and a base contact coupled with the base; whereby, signals applied with respect to the collector, base, and emitter contacts causes light emission from the base by radiative recombination in the base.

PNP light emitting transistor and method

A method for producing an optical output, including the following steps: providing first and second electrical signals; providing a bipolar light-emitting transistor device that includes collector, base, and emitter regions; providing a collector electrode coupled with the collector region and an emitter electrode coupled with the emitter region, and coupling electrical potentials with respect to the collector and emitter electrodes; providing an optical coupling in optical communication with the base region; providing first and second base electrodes coupled with the base region; and coupling the first and second electrical signals with the first and second base electrodes, respectively, to produce an optical output emitted from the base region and coupled into the optical coupling, the optical output being a function of the first and second electrical signals.

Semiconductor light emitting devices and methods

A method for producing controllable light pulses includes the following steps: providing a heterojunction bipolar transistor structure including collector, base, and emitter regions of semiconductor materials; providing an optical resonant cavity enclosing at least a portion of the transistor structure; and coupling electrical signals with respect to the collector, base, and emitter regions, to switch back and forth between a stimulated emission mode that produces output laser pulses and a spontaneous emission mode. In a form of the method, the electrical signals include an AC excitation signal, and part of each excitation signal cycle is operative to produce stimulated emission, and another part of each excitation signal cycle is operative to produce spontaneous emission.

Semiconductor laser devices and methods

A high life cycle and low voltage MEMS device. In an aspect of the invention, separate support posts are disposed to prevent a suspended switch pad from touching the actuation pad while permitting the switch pad to ground a signal line. In another aspect of the invention, cantilevered support beams are made from a thicker material than the switching pad. Increased thickness material in the cantilever tends to keep the switch flat in its resting position. Features of preferred embodiments include dimples in the switch pad to facilitate contact with a signal line and serpentine cantilevers arranged symmetrically to support the switch pad.

High cycle MEMS device

A high life cycle MEMS device is provided by the invention. The inventors have recognized that the deflection beam or deflection beams of an MEMS shunt switch are a failure point in need of improvement. In an aspect of the invention, at least a portion of the signals in the grounded state of an MEMS shunt switch are bypassed to ground on a path that avoids the deflection beam(s) supporting the movable pad. In a preferred embodiment, ground posts are disposed to contact the movable pad in an actuated position and establish a signal path from a signal line to ground. The inventors have also recognized that a shape of deflection beams near their anchor point contributes to failures. In another preferred aspect of the invention, an anchoring portion of the deflection beam or deflection beams is generally coplanar with the remaining portion of the deflection beam(s). An additional post beneath the anchoring portion of the deflection beam(s) permits deflection beam(s) lacking any turns that form a weak structural point.

Growing community of inventors

Champaign, IL, United States of America

Richard Chan