NITRIDE SEMICONDUCTOR DEVICE HAVING ALUMINUM OXIDE FILM AND A PROCESS FOR PRODUCING THE SAME

摘要

A transistor primarily made of nitride semiconductor materials and a passivation film of Al2O3, and a process for producing the same are disclosed. The transistor, which is the type of the high-electron mobility transistor (HEMT), has a channel layer and a barrier layer sequentially grown on a semiconductor substrate. The barrier layer in a surface thereof is covered with Al2O3 film. A feature of the transistor of the invention is that Al2O3 film is formed by the atomic layer deposition (ALD) at relatively lower deposition temperature lower than 150° C., which leaves methyl groups and/or carbonyl groups in substantial concentrations measured by the Fourier transform infrared spectroscopy (FTIR).

主权项

1. A semiconductor device, comprising:
a semiconductor stack including, on a substrate, a channel layer made of nitride semiconductor material and a barrier layer made of nitride semiconductor material, the semiconductor stack providing a two dimensional electron gas (2-DEG) in an interface between the channel layer and the barrier layer; and an aluminum oxide (Al2O3) film provided on the semiconductor stack, the aluminum oxide film containing at least one of a methyl group (—CH3) and a carbonyl group (—COOH) with a total concentration greater than 5% of a concentration of Al2O3 determined by a ratio of absorbance intensity of the methyl group, the carbonyl group, and the Al2O3 measured by a Fourier Transform Infrared Spectroscopy (FTIR).