Fabrication and Electrical Properties of Al 2 O 3 /GaN MIS Structures using Remote Plasma Atomic Layer Deposition
thin films were deposited on GaN(0001) by using a Remote Plasma Atomic Layer Deposition(RPALD) technique with a trimethylaluminum(TMA) precursor and oxygen radicals in the temperature range of . The growth rate per cycle was varied with the substrate temperature from /cycle at to /cycle at . The chemical structure of the thin films was studied using X-ray photoelectron spectroscopy(XPS). The electrical properties of /GaN Metal-Insulator-Semiconductor (MIS) capacitor grown at a process temperature were excellent, a low electrical leakage current density( at 1 MV) at room temperature and a high dielectric constant of about 7.2 with a thinner oxide thickness of 12 nm. The interface trap density() was estimated using a high-frequency C-V method measured at . These results show that the RPALD technique is an excellent choice for depositing high-quality as a Sate dielectric in GaN-based devices.