Search

Studies the lead zirconate titanate (PZT) interfacial reaction caused by low-temperature annealing and resulting change in the surface Fermi level position using the x-ray photoelectron spectroscopy (XPS). Experimental framework of the study; Effects of annealing prior to platinum (Pt) deposition; Effects of annealing on a Pt-deposited PZT surface; Role of Pt in hydrogen and oxygen annealing.

A nonlinear III–V field-effect transistor model is proposed for designing microwave antenna switches and related circuits. off-state gate and drain capacitance values of a pseudomorphic high-electron-mobility transistor (HEMT) derived from pulsed S-parameters with a deep off-state quiescent gate voltage are found to be much less voltage dependent than capacitance values measured by a nonpulsed bias owing to trap-induced dispersion effects. Our device model based on pulsed-bias CV characteristics accurately simulates switch nonlinearity. Both gate and drain capacitance values are assumed to be nonlinear, and a charge expression is developed for model implementation. For both capacitance values, a nonpulsed-bias CV curve is also utilized to maintain accurate capacitance at the quiescent voltage and, thus, accurate simulation of off-switch isolation. Additional terms are introduced to an existing drain current model to improve accuracy at high Vgs/\low\ Vds and subthreshold regions. Furthermore, the model is extended to multiple-gate devices. Harmonics generated from both off- and on -state switches, insertion loss, and isolation are accurately predicted for both single- and multiple-gate HEMTs. [ABSTRACT FROM AUTHOR]

Presents a study which investigates a device degradation characterized as an increase in the gate leakage current due to continuous reverse-voltage stress for a doped channel HIGFET (heterostructure insulated-gate field-effect transistor). Degradation characteristics; Suppression of degradation by surface treatment.

Examines metal-insular-semiconductor diodes with a Se-treated interface and photochemical-vapor-deposited SiO[sub 2]. Frequency dispersion in the capacitance of diodes; Reduction of density interface states near the midgap; Effects of Se-treated AlGaAs thin layer at the insular interface on the number of interface states.

Develops a digital etching technique for gallium arsenide using selenium (Se) molecular beam and atomic hydrogen beam. Induction of selenium and arsenic exchange reaction through Se molecular beam irradiation; Selective removal of gallium[sub 2]selenium[sub 3] by atomic hydrogen beam; Involvement of a self-limiting mechanism in the etching process.

Electrical properties of LaB6/GaAs(001) Schottky diodes have been studied by current-voltage measurements. The diodes were made by depositing LaB6 on chemically etched GaAs and molecular beam epitaxy prepared GaAs-c(4×4) surfaces by electron beam evaporation. The barrier height and ideality factor show appropriate values for metal-semiconductor field-effect-semiconductor application and do not change much by high-temperature annealing. These results provide firm evidence that LaB6 is a very promising candidate for self-aligned gate material of GaAs integrated circuits. [ABSTRACT FROM AUTHOR]