A review of recent and current work on microwave FET's and amplifiers is presented, and an extensive bibliography of recent articles is appended (250 references). First, the various FET structures (MRSFET's, JFET's, and IGFET's) and their performances are reviewed. Second, the principle of operation is outlined for Si- and GaAs-MESFET's; the basic device physics, equivalent circuit, high-frequency limitations, and noise behavior are treated. Third, the design principles and performance of microwave MESFET amplifiers are summarized.

Microwave Field-Effect Transistors--1976

A review of radiation-induced displacement damage effects in semiconductor devices is presented, with emphasis placed on silicon technology. The history of displacement damage studies is summarized, and damage production mechanisms are discussed. Properties of defect clusters and isolated defects are addressed. Displacement damage effects in materials and devices are considered, including effects produced in silicon particle detectors, visible imaging arrays, and solar cells. Additional topics examined include NIEL scaling, carrier concentration changes, random telegraph signals, radiation hardness assurance, and simulation methods for displacement damage. Areas needing further study are noted.

Displacement Damage Effects in Irradiated Semiconductor Devices

An integrated inverter stage operating in the gigabit range at a static power dissipation of 100 µW was built for future use in LSI logic circuits. Planar gallium arsenide technology was employed using selective ion-implanted enhancement mode junction field-effect transistors (E-JFET) having 3-µm gate lengths. A nine-stage ring oscillator served as a test vehicle to assess the speed-power product for digital applications. A theoretical analysis shows the transistor operates during the switching transient in the saturation regime, notwithstanding steady-state operation in the linear regime. When the transistor is switched off, the transient response is governed by the load resistance and the input capacitance of the subsequent stage. Means of reducing the switching time by increasing the supply voltage, nonlinear load devices, an output buffer stage, and reduction of gate length and width are described. Directly coupled E-JFET logic does not require level shifting, and, therefore, offers advantages over depletion-mode gallium arsenide MESFET logic by reducing the number of circuit elements per gate. Projected gallium arsenide E-JFET LSI logic circuits will surpass silicon-based bipolar logic with respect to both speed and power, and n-channel silicon MOS logic with respect to speed.

Femtojoule high speed planar GaAs E-JFET logic

The design and performance of an X-band amplifier with GaAs Schottky-gate field-effect transistors are described. The amplifier achieves 20 /spl plusmn/ 1.3-dB gain with a 5.5-dB typical noise figure (6.9 dB maximum) over the frequency range of 8.0-12.0 GHz. The VSWR at the input and output ports does not exceed 2.5:1. The minimum output power for 1-dB gain compression is +13 dBm, and the intercept point for third-order intermodulation products is +26 dBm. The design of practical wide-band coupling networks is discussed. These networks minimize the overall amplifier noise figure and maintain a constant gain in the band.

Design and Performance of Microwave Amplifiers with GaAs Schottky-Gate Field-Effect Transistors

GaAs field-effect transistors for linear and digital circuits are finding applications in systems that have to function in a nuclear environment. This paper reviews and analyzes the radiation damage mechanisms in GaAs material and applies the material parameter changes to predict changes of electrical parameters of junction field-effect transistors due to exposure to fast neutrons and total dose ionizing radiation. The transient response to pulsed ionizing radiation is analyzed and experimental results are correlated with theoretical predictions. Annealing characteristics of radiation-generated defects are described. The prospects for hardening GaAs fieldeffect transistor integrated circuits against the effects of nuclear radiation are assessed.

Radiation Effects in Gaas Junction Field-Effect Transistors

Carrier removal and mobility degradation in epitaxially grown n-type GaAs, due to exposure to fast neutrons, is reported. The variations in carrier concentrations and mobilities are utilized to predict the transconductance degradation of GaAs JFET's as a function of neutron fluence. Experimental results up to a fluence of 8 \times 10^{15} n/cm2are reported and correlated with theory.

A.F. Behle

Papers

Fast neutron tolerance of GaAs JFET's operating in the hot electron range