Deposition Mechanism and Electrical Property of CeO2 Thin Films by MOCVD with H2O Introduction

Abstract

Cerium dioxide (CeO2) thin films are prepared by means of the metal organic chemical vapor deposition (MOCVD) using tetrakis (3-methyl-3-pentoxy) cerium with and without H2O vapor introduction. A large amount of H2O (more than 2 sccm) acts as an oxidant and as a result the deposition rate increases by up to four times at the deposition pressure of 2.0 Pa, leading to the temperature independence of the deposition rate. At the low deposition temperature of 270 åC, a small amount of H2O (0.1-0.2 sccm) suppresses the deposition because of its preferential occupation of the surface sites. The CeO2 film annealed at 600 åC in the oxidizing ambient shows steep C-V characteristics with no flat band voltage shift nor hysteresis.