Development of a Cluster Tool and Analysis of Deposition of Silicon Oxide by TEOSO2 PECVD

Abstract

AbstractA single wafer cluster tool was developed. It is composed of a central robot arm wafer handler and three processing chambers: a RF PECVD chamber, a microwave after glow RPECVD chamber and a rapid thermal annealing chamber. The tool is designed to allow high flexibility, with in-situ multi-sequential processing capability. An in depth study of the deposition of silicon oxide by PECVD was performed. As unique features, it handles TEOS vapor without a carrier gas and it includes a double stage gas distribution system. The films were characterized by means of: ellipsometry, FTIRS, RBS, AES, SIMS, stress and etch rate in diluted (1:100) HF solution. Good uniformity (>98 %) was obtained. The results show that the quality of the films is most influenced by the wafer temperature and flux of oxygen. For the best condition, the following results were obtained: deposition rate of 370 nm/min., refraction index of 1.46, stoichiometry of 2.0, intrinsic stress of 1.3×109 dyn/cm2, carbon content below the AES and SIMS detection limit and low OH content. We also propose a model that fits our results.