Abstract:
A method for producing light emission from a two terminal semiconductor device with improved efficiency, includes the following steps: providing a layered semiconductor structure including a semiconductor drain region comprising at least one drain layer, a semiconductor base region disposed on the drain region and including at least one base layer, and a semiconductor emitter region disposed on a portion of the base region and comprising an emitter mesa that includes at least one emitter layer; providing, in the base region, at least one region exhibiting quantum size effects; providing a base/drain electrode having a first portion on an exposed surface of the base region and a further portion coupled with the drain region, and providing an emitter electrode on the surface of the emitter region; applying signals with respect to the base/drain and emitter electrodes to obtain light emission from the base region; and configuring the base/drain and emitter electrodes for substantial uniformity of voltage distribution in the region therebetween. In a further embodiment lateral scaling is used to control device speed for high frequency operation.
Abstract:
A method for controlling operation of a transistor includes the following steps: providing a bipolar transistor having emitter, base and collector regions; applying electrical signals to the transistor to produce light emission from the transistor; effecting photon-assisted tunneling of carriers in the transistor with self-generated photons of the light emission, and controlling operation of the transistor by controlling the photon-assisted tunneling.
Abstract:
A method for producing an optical output includes 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. Also disclosed in an improved pnp transistor laser and a technique for switching back and forth between a stimulated emission mode that produces output laser pulses and a spontaneous emission mode.
Abstract:
A two terminal semiconductor device for producing light emission in response to electrical signals, includes: a terminal-less semiconductor base region disposed between a semiconductor emitter region and a semiconductor collector region having a tunnel junction adjacent the base region; the base region having a region therein exhibiting quantum size effects; an emitter terminal and a collector terminal respectively coupled with the emitter region and the collector region; whereby application of the electrical signals with respect to the emitter and collector terminals, causes light emission from the base region. Application of the electrical signals is operative to reverse bias the tunnel junction. Holes generated at the tunnel junction recombine in the base region with electrons flowing into the base region, resulting in the light emission. The region exhibiting quantum size effects is operative to aid recombination.
Abstract:
A field-effect transistor device, including: a semiconductor heterostructure comprising, in a vertically stacked configuration, a semiconductor gate layer between semiconductor source and drain layers, the layers being separated by heterosteps; the gate layer having a thickness of less than about 100 Angstroms; and source, gate, and drain electrodes respectively coupled with said source, gate, and drain layers. Separation of the gate by heterosteps, rather than an oxide layer, has very substantial advantages.
Abstract:
Methods and devices are disclosed for producing controllable light emission from a bipolar transistor. Also, a method is disclosed for increasing the speed of a bipolar transistor, including the following steps: providing a bipolar transistor having emitter (150), base (140), and collector (130) regions; providing electrodes (115, 145, 165) for coupling electrical signals with the emitter (150), base (140), and collector (130) regions; and adapting the base region (140) to enhance stimulated emission to the detriment of spontaneous emission, so as to reduce carrier recombination lifetime in the base region (140).
Abstract:
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.
Abstract:
A ring cavity light-emitting transistor device, including: a planar semiconductor structure of a semiconductor base layer of a first conductivity type between semiconductor collector and emitter layers of a second conductivity type; base, collector, and emitter metalizations respectively coupled with the base layer, said collector layer, and said emitter layer, the base metalization including at least one annular ring coupled with a surface of the base layer; and an annular ring- shaped optical resonator in a region of the semiconductor structure generally including the interface of the base and emitter regions; whereby application of electrical signals with respect to the base, collector, and emitter metalizations causes light emission in the base layer that propagates in the ring-shaped optical resonator cavity.
Abstract:
A semiconductor light emitting device, including: a heterojunction bipolar light-emitting transistor having a base region between emitter and collector regions; emitter, base, and collector electrodes for coupling electrical signals with the emitter, base, and collector regions, respectively; and a quantum size region in the base region; the base region including a first base sub-region on the emitter side of the quantum size region, and a second base sub-region on the collector side of the quantum size region; and the first and second base sub- regions having asymmetrical band structures. Also disclosed is a method for producing light emission from a two-terminal semiconductor structure, including the following steps: providing a semiconductor structure that includes a first semiconductor junction between an emitter region of a first conductivity type and a base region of a second conductivity type opposite to that of the first conductivity type, and a second semiconductor junction between the base region and a drain region; providing, within the base region, a region exhibiting quantum size effects; providing an emitter electrode coupled with the emitter region; providing a base/drain electrode coupled with the base region and the drain region; and applying signals with respect to the emitter and base/drain electrodes to obtain light emission from the semiconductor structure.
Abstract:
A first form of a method for producing an optical output in substantially linear relationship with an electrical AC signal, includes the following steps: providing a light-emitting transistor having emitter, base, and collector regions, and associated respective emitter, base, and collector terminals, the transistor having a light-emitting output port; applying the AC signal to a first input port defined across a given one of the terminals and a common one of the terminals; applying an amplified version of the AC signal to a second input port defined across a further one of the terminals and the common one of the input terminals; and selecting an amplification of the amplified version of the AC signal to substantially cancel a nonlinearity characteristic of the light emitting transistor. A second form of the method involves predistortion feedback linearization of an optical signal using a light-emitting transistor or transistor laser.