J. Phys. IV France 03 (1993) C3-337-C3-343
Process characterization for LPCVD TEOS-ozone based SiO2 filmsL. ZANOTTI1, S. ROJAS1, F. DOGHIERI2 and F. SANTARELLI2
1 SGS-Thomson Microelectronics, Via C. Olivetti 2, 20041 Agrate Brianza, Italy
2 Dipartimento di Ingegneria Chimica e di Processo, Università degli Studi di Bologna, Viale Risorgimento 2, 40136 Bologna, Italy
Process characterization of 400 nm thick LPCVD-SiO2 films based on TEOS-Ozone chemistry was performed. Films were deposited on six inch silicon wafers using a single wafer cluster system. The process characterization was carried out starting from a standard process taken as reference, around which the main process parameters, temperature (300-430°C), pressure (50-80 torr), and gas ratio (3:l-7:1), were varied one at a time whilst keeping the remainder fixed. The effect of process parameters on deposition rate, thickness uniformity within wafer, film stress, etch rate and refractive index was investigated. On the basis of these results the optimum working conditions for the industrial implementation of the process were determined and proven for sidewall spacer formation and lMbit EPROM devices. An interpretation of the data of deposition rate is provided in terms of the elementary processes involved.
© EDP Sciences 1993