Electrical Properties of Chemical-Mechanical Polished Tetraethyl Orthosilicate Films with and Without Capping Layers

Abstract

The quality and interface characteristics of chemical-mechanical (chem-mech) polished, 100 nm thick, tetraethyl orthosilicate (TEOS) films have been characterized by electrical testing. As a result of the polishing, the breakdown characteristics of the TEOS films were significantly degraded. Several techniques for restoring oxide quality including annealing and the use of capping layers consisting of thin plasma-enhanced chemical vapor deposited (PECVD) SiO2 films were evaluated. Our results indicate that a 100 W helium plasma (with 1% oxygen) treatment followed by the deposition of a thin PECVD silicon dioxide film was an effective method for improving the electrical integrity of these polished films. © 1991, The Electrochemical Society, Inc. All rights reserved.