DC breakdown and TDDB study of ALD SiO2 on GaN

摘要

Dielectric and MOS interface properties of SiO2 deposited with atomic layer deposition (ALD) on GaN with several surface treatment and oxide structures have been investigated via DC measurements. ALD SiO2 on dry etch + NaOH-treated GaN surface exhibited higher breakdown voltage with small distribution, larger barrier height characteristic, and higher charge to breakdown characteristics when compared with un-etched surface condition and dry + TMAH wet etched surface condition, demonstrating the usability of NaOH post-etching treatment. Comparison was also made to a composite oxide of SiO2/Al2O3/SiO2, showing different trap-related leakage conduction.