Modeling of Epitaxial Silicon Growth from the DCS-H₂-HCl System in a Large Scale CVD Reactor

Multi-wafer planetary type chemical vapor deposition (CVD) reactors are widely used in thin film growth and suitable for large scale production. In this paper, numerical modeling has been carried out to simulate transport phenomena and epitaxial silicon growth in a planetary CVD reactor for the SiH₂Cl₂-H₂-HCl system. A chemical reaction model using temperature dependent reaction rate is proposed and validated using experimental data. Based on the model, the effect of various operation conditions such as satellite rotational speed, species concentration, operating temperature and pressure is considered to determine the key factor influencing the growth rate and uniformity. The results reveal that the growth rate and uniformity are strongly related to total flow rate, species concentration and operating pressure, but are not affected by rotational speed of the satellite in case of high flow rates. Growth rates are found to be increased from 0.02 μm /min at operating pressure of 10 torr to approximately 0.16 μm/min at 150 torr. Growth deposition non-uniformity decreases from 80% for total flow rate of 460 slm to 13% for total flow rate of 46 slm.