Schottky barrier height enhancement for In/sub 0.52/AlAs layer by using in-situ Ar plasma pre-treatment and its application to In/sub 0.52/AlAs/In/sub 0.53/GaAs/InP HEMT's

To increase a Schottky barrier height (SBH) for In/sub 0.52/AlAs layer, in-situ Ar plasma pre-treatment method was proposed. Through the pre-treatment of Ar plasma before Schottky metallization, a SBH of +1.05 eV for In/sub 0.52/AlAs layer was obtained by C-V measurement for a vertical type Schottky diode. It was thought to be an effective removal of native oxide on InAlAs layer. More pre-treatment would result in a decrease of SBH due to a plasma induced damage effect. This process was applied to fabricate In/sub 0.52/AlAs/In/sub 0.53/GaAs/InP HEMT, which led to an improvement in sub-threshold leakage, sub-threshold swing and reverse breakdown voltage characteristics.