Highly scaled equivalent oxide thickness of 0.66nm for TiN/HfO2/GaSb MOS capacitors by using plasma-enhanced atomic layer deposition

Abstract

Through in situ hydrogen plasma treatment (HPT) and plasma-enhanced atomic-layer-deposited TiN (PEALD-TiN) layer capping, we successfully fabricated TiN/HfO2/GaSb metal-oxide-semiconductor capacitors with an ultrathin equivalent oxide thickness of 0.66nm and a low density of states of approximately 2 x 10(12)cm(-2) eV(-1) near the valence band edge. After in situ HPT, a native oxide-free surface was obtained through efficient etching. Moreover, the use of the in situ PEALD-TiN layer precluded high-. dielectric damage that would have been caused by conventional sputtering, thereby yielding a superior high-. dielectric and low gate leakage current. (C) 2017 The Japan Society of Applied Physics