AlGaN/GaN metal-oxide-semiconductor high electron mobility transistors using directly grown oxide layer

Abstract

A photoelectrochemical oxidation method was used to directly grow oxide film on the Al <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.15</inf> Ga <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.85</inf> N as the insulation film of the AlGaN/GaN metal-oxide-semiconductor high electron mobility transistors (MOS-HEMTs). The gate leakage current at reverse bias of V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">GS</inf> = -7V is 10nA. Even the reverse bias is V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">GS</inf> =-60V, the leakage current is only 102nA. An unity gain cutoff frequency (f <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</inf> ) of 5.6 GHz and a maximum frequency of oscillation (f <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">max</inf> ) of 10.6 GHz were measured. These electrical performances are much better than those of GaN-based conventional MES-HEMTs.