Accession Number : ADA309709

Title :   Circuits and Devices for High-Speed Instrumentation.

Descriptive Note : Final rept. 1 Aug 95-31 Jan 96,

Corporate Author : FOCUSED RESEARCH INC SANTA CLARA CA

Personal Author(s) : Marsland, Robert A. ; Mirabedini, All ; Botez, Dan

PDF Url : ADA309709

Report Date : 24 MAY 1996

Pagination or Media Count : 59

Abstract : In this report we detail the development of a GaAs based RID that outperforms all other GaAs based RTD devices and many other devices in more exotic materials systems with >3OOkA/cm2 peak current density at 1.2V. This result was achieved by using a strained InGaAs well to increase peak current density while the valley current was kept low (>2:1 peak to valley ratio) by achieving smooth InGaAs/AlGaAs interfaces through the use of on orientation MOCVD growth. Circuits were designed and simulated using the measured parameters of the fabricated devices including an RTD driven sampling gate and an RTD based digital time delay. These two circuits form the basic building blocks of time interval measurement and multichannel sampling systems. A planar transformer was devised to allow the low - about 1 V - output of the RTD to drive a 4 or 6 diode sampling bridge Through the successful fabrication and circuit simulation based demonstration of device performance, we have shown the feasibility of measurement instruments based on this technology.

Descriptors :   *TUNNELING(ELECTRONICS), *GATES(CIRCUITS), DIGITAL SYSTEMS, TIME INTERVALS, RATIOS, GALLIUM ARSENIDES, CURRENT DENSITY, MODULAR CONSTRUCTION, PEAK POWER, FEASIBILITY STUDIES, PLANAR STRUCTURES, ELECTRIC CURRENT, ELECTRICAL MEASUREMENT, TRANSFORMERS, MULTICHANNEL.

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE