Conformal Properties of InSbTe Thin Films Grown at a Low Temperature by MOCVD for PRAM Applications

Abstract

The feasibility of InSbTe chalcogenide materials prepared by metallorganic chemical vapor deposition (MOCVD) for phase-change memory (PRAM) applications was demonstrated. Films grown below 225 degrees C exhibited an amorphous structure, and the films grown at 300 degrees C included various crystalline phases such as In-Sb-Te, In-Sb, In-Te, and Sb-Te. The composition of the amorphous films grown at 225 degrees C was dependent on the working pressure. Films grown at 225 degrees C exhibited a smooth morphology with a root-mean-square roughness of less than 1 nm, and the step coverage of the films grown on a trench structure with an aspect ratio of 5:1 was greater than 90%. An increase in deposition time increased the filling rate while retaining the conformal step coverage. Films grown at 225 degrees C for 3 h in a working pressure of 13 x 10(2) Pa exhibited a reproducible and complete filling in a trench structure. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3363618] All rights reserved.