Accession Number : ADA294512

Title :   Investigation of GaAs Layers Grown by Molecular Beam Epitaxy at Low Temperature.

Descriptive Note : Final rept. 1 Oct 91-30 Sep 94,

Corporate Author : MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB

Personal Author(s) : Chen, Chang-Lee

PDF Url : ADA294512

Report Date : 10 MAR 1995

Pagination or Media Count : 79

Abstract : Over the three-year course of this program, the low-temperature-grown (LTG) GaAs and AlGaAs have been incorporated as the gate insulator or surface passivation in a variety of field-effect-transistors (FETs). The LTG GaAs used as the surface passivation layer in a metal-semiconductor FET (MESFET) with a novel overlapping gate structure increased the breakdown voltage by two folds compared to a regular MESFET. The LTG GaAs passivation also greatly improved the surface quality of the device, resulting in a reduced low-frequency noise and minimal frequency dispersions of the transconductance and the output resistance. The mechanisms for the improved breakdown voltage have been studied by computer simulation. Self-aligned GaAs metal- insulator-semiconductor FETs (MISFETs) having an LTG GaAs gate insulator--have been developed. The performance of the MISFET was improved significantly by the ion-implanted high-doping-concentration source and drain regions. A variety of the LTG GaAs and LTG AlGaAs with different Al mole fractions, that can used as the gate insulator, have been grown to study the effects of the growth temperature and the thickness on the properties of the MISFETs. jg

Descriptors :   *LOW TEMPERATURE, *GALLIUM ARSENIDES, *ALUMINUM GALLIUM ARSENIDES, *EPITAXIAL GROWTH, *MOLECULAR BEAMS, COMPUTERIZED SIMULATION, FREQUENCY, OUTPUT, METALS, THICKNESS, LAYERS, INSULATION, RESISTANCE, GATES(CIRCUITS), VOLTAGE, FIELD EFFECT TRANSISTORS, SEMICONDUCTORS, ION IMPLANTATION, ALIGNMENT, SURFACES, DRAINAGE, SELF OPERATION, NOISE REDUCTION, LOW FREQUENCY, BREAKDOWN(ELECTRONIC THRESHOLD), FOLDING, TRANSCONDUCTANCE, PASSIVITY, DISPERSIONS, ELECTRICAL INSULATION.

Subject Categories : Inorganic Chemistry
      Physical Chemistry
      Electrical and Electronic Equipment
      Crystallography
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE