The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 13, 1990
Filed:
Jun. 22, 1989
Daniel C Buck, Hanover, MD (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
A high speed optical sensor comprising a parallel array of vertical field effect transistors and optical fibers disposed in the recesses between the transistors is disclosed herein. Each of the vertical field effect transistors includes a substrate of doped gallium arsenide divided by a depleted region. One side of each of the gallium arsenide substrates is flanked by an optical fiber which transmits an optical signal into one side of the depleted region, while the other side of the substrate includes a gate electrode for controlling the flow of photo charges induced in the depleted region by the light signals. The gate electrode serves not only to control the flow of charges through the transistor but also reflects back a portion of the light emanated by the optical fiber so that it passes a second time through the depleted region. The efficient light coupling that occurs between the optical fibers and the depleted regions of the substrates of the vertical FET's, in combination with the low capacitive leakage afforded by the design at high frequencies and the high power density obtainable with vertical FET's results in a photosensor which is advantageously efficient, fast the compact.