n- and p-channel TaN/HfO2 MOSFETs on GaAs substrate using a germanium interfacial passivation layer

Using a thin germanium interfacial passivation layer (IPL), for the first time we present surface channel n- and p-MOSFETs on GaAs substrate with TaN gate electrodes and HfO₂ dielectric films. We used self-aligned and gate-last processes to fabricate MOSFETs on semi-insulating GaAs substrate. The electrical results from the buried channel and the surface channel-mode transistors are investigated. Both n- and p-channel transistors show excellent surface channel dc output characteristics, providing a good possibility of utilizing GaAs in CMOS technology.