GaSb Metal-Oxide-Semiconductor Capacitors with Atomic-Layer-Deposited HfAlO as Gate Dielectric

Chen Wang, Birck Nanotechnology Center, Purdue University; Fudan University
Min Xu, Birck Nanotechnology Center, Purdue University
Jiangjiang Gu, Birck Nanotechnology Center, Purdue University
David Wei Zhang, Fudan University
Peide D. Ye, Birck Nanotechnology Center, Purdue University

Abstract

An interface characterization of p-type GaSb metal-oxide-semiconductor (MOS) structures has been performed with Al-first and Hf-first HfAlO gate dielectrics deposited via atomic layer deposition. The Al-first process is found to improve the characteristic of high-k/GaSb MOS such as breakdown strength, frequency dispersion in accumulation region and gate dependent capacitance modulation. From temperature dependent conductance method, an interface trap density of 4 x 10(12) cm(-2) eV(-1) near the valence band edge is extracted for Al-first HfAlO/GaSb. The border trap density is found to be 4.5 x 10(19) cm(-3) with a barrier height of 2.75 eV below the valence band edge of GaSb. (C) 2011 The Electrochemical Society. [DOI: 10.1149/2.001203esl] All rights reserved.

Discipline(s)

Nanoscience and Nanotechnology