Accession Number : ADA189634

Title :   Examination of Temperature Effects on Gate-to-Drain Avalanche Breakdown in GaAs MESFETs (Metal-Semiconductor Field Effect Transistors) by Measuring Light Emission under RF Drive.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s) : Robb, Roger E

PDF Url : ADA189634

Report Date : Dec 1987

Pagination or Media Count : 161

Abstract : This investigation examines temperature effects on avalanche breakdown in GaAs MESFETs to determine if this failure mechanism is accelerated by high temperature life tests. The specific objective is to assess whether the accelerated life test evaluations performed on a GaAs MESFET planned for use in future Defense Satellite Communications System (DSCS) spacecraft have adequately addressed the reliability issues concerning the gate-to-drain avalanche breakdown failure mechanism. This objective was accomplished by adapting an existing analytical model for temperature effects, and using it to predict the variation in avalanche multiplication activity with temperature. To verify this model, it was used to calculate the associated changes in light emissions over temperature which were experimentally validated on one device of the type planned for use by the DSCS program. Once validated, these models were used to evaluate the adequacy of the accelerated temperature life tests. The results of this evaluation indicate that the the avalanche breakdown failure mechanism is decelerated with temperature, and therefore, the effects of avalanche breakdown on the reliability of GaAs MESFETs cannot be determined by accelerated temperature life testing.

Descriptors :   *AVALANCHE EFFECT(ELECTRONICS), *FIELD EFFECT TRANSISTORS, *SATELLITE COMMUNICATIONS, *SEMICONDUCTORS, ACCELERATED TESTING, DEFENSE SYSTEMS, DRIVES, EMISSION, FAILURE(MECHANICS), HIGH TEMPERATURE, LIFE TESTS, LIGHT, MATHEMATICAL MODELS, MEASUREMENT, METALS, MULTIPLICATION, RADIOFREQUENCY, RELIABILITY, SPACECRAFT, TEMPERATURE, TEST AND EVALUATION, TEST METHODS, THESES

Subject Categories : Electrical and Electronic Equipment
      Solid State Physics
      Command, Control and Communications Systems

Distribution Statement : APPROVED FOR PUBLIC RELEASE