Particle Simulaiton of a Silicon Deposition in LPCVD

• Main Authors: Wei-Chung Hsiao, 蕭惟中
• Other Authors: Jong-Shinn Wu
• Format: Others
• Language: en_US
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/19348290410739636605

碩士 === 國立交通大學 === 機械工程系 === 89 === Particle simulation of silicon Chemical Vapor Deposition (CVD) process is proposed using the Direct Simulation Monte Carlo (DSMC) method. Conservative weighting scheme [Boyd, 1996] is used to deal with the trace species often involved in CVD, which is otherwise considered computationally impossible using the conventional DSMC method. This conservative weighting scheme (CWS) improves greatly the statistical uncertainties by decreasing the weighting factors of trace-species particles and ensures the conservation of both momentum and energy between two colliding particles with large difference of weighting factors. A single-cell equilibrium simulation is performed for verification of the CWS. Results show that it is most efficient and accurate for weight ratio lower than 0.05 for flows with 2 and 3 species. Rotational energy exchange using the CWS has been evaluated for mixture with 2 species. Simulations of both gas-phase reaction and surface reactions show that only Extended CWS can produce reasonable results. Finally, ECWS is used to simulate the silicon deposition in the LPCVD chamber using a supersonic jet.