High-gain AlGaAs/GaAs double heterojunction Darlington phototransistors for optical neural networks
US5027182A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 11, 1990 |
| Grant date | Jun 25, 1991 |
| Priority date | — |
| Expiry date | Oct 11, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H29/10
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
High-gain MOCVD-grown (metal-organic chemical vapor deposition) AlGaAs/GaAs/AlGaAs n-p-n double heterojunction bipolar transistors (DHBTs) (14) and Darlington phototransistor pairs (14, 16) are provided for use in optical neural networks and other optoelectronic integrated circuit applications. The reduced base (22) doping level used herein results in effective blockage of Zn out-diffusion, enabling a current gain of 500, higher than most previously reported values for Zn-diffused-base DHBTs. Darlington phototransistor pairs of this material can achieve a current gain of over 6,000, which satisfies the gain requirement for optical neural network designs, which advantageously may employ novel neurons (10) comprising the Darlington phototransistor pair in series with a light source (12).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.