Characteristics of Si3N4/GaAs metal-lnsulator-semiconductor interfaces with coherent Si/Al0.3Ga0.7As interlayers

Abstract

Si3N4/GaAs metal-insulator-semiconductor (MIS) interfaces with Si(10A)/ Alo 3Gao.TAS (20A) interface control layers have been characterized using capacitance-voltage (C-V) and conductance methods. The structure was in situ grown by a combination of molecular beam epitaxy and chemical vapor deposition. A density of interface states in the 1.1 x 10 '1 eV -1 cm -2 range near the GaAs midgap as determined by the conductance loss has been attained with an ex situ solid phase annealing of 600~ in N 2 ambient. A dip quasi-static C-V demonstrating the inversion of the minority-carrier verifies the decent interface quality of GaAs MIS interface. The hysteresis and frequency dispersion of the MIS capacitors were lower than 100 mV, some of them as low as 50 mV under a field swing of about +2 MV/cm. The increase of the conductance loss at higher frequencies was observed when employing the surface potential toward conduction band edge, suggesting the dominance of faster traps. Self-aligned gate depletion mode GaAs metal-insulator-semiconductor field-effect transistors with Si/A103Gao7As interlayers having 3 ~tm gate lengths exhibited a transconductance of about 114 mS/ram. The present article reports the first application of pseudomorphic Si/ Alo ~Gao.r~ interlayers to ideal GaAs MIS devices and demonstrates a favorable interface stability.

Improvement of SiNx:H/InP gate structures for the fabrication of metal insulator semiconductor field-effect transistors

“…In general, to improve the insulator/semiconductor interface and, consequently, to reduce the semiconductor surface degradation, it is necessary to use an insulator deposition technique that reduces the ion bombardment and radiation damage during the deposition process, and provides good quality insulator at low deposition temperatures. This points to the electron cyclotron resonance chemical vacuum deposition (ECR-CVD) method as a soft technique to deposit device quality SiN x :H. This insulator has proven to be the best choice as gate insulator on MISFET devices based on III-V compound semiconductors [1,2].…”