Atomic layer deposited high-k Hf_xAl_(1-x)O as an alternative gate dielectric for 4H-SiC MIS based transistors

HfxAl(1-x)O film grown by atomic layer deposition(ALD) on n-type 4H-SiC(0001) epitaxial layer has been studied.Measurements show that it has relatively high breakdown electric field of 16.4 MV/cm,high dielectric constant of 16.3 and low gate leakage current of 2.47×10-5 A/cm2 at E=5 MV/cm,which makes ALD HfxAl(1-x)O a great potential candidate gate dielectric for 4H-SiC MIS based transistors.