NUMERICAL MODELING OF PARTICLE DYNAMICS IN A ROTATING-DISK CHEMICAL-VAPOR-DEPOSITION REACTOR

Particle contamination is considered to be one of the major problem ar eas in the processing of semiconductors via chemical vapor deposition (CVD). Thus it is very important to acquire an understanding of partic le transport processes in CVD reactors. This paper addresses this issu e by presenting the results of a numerical simulation of particle dyna mics in a rotating disk CVD reactor. The background flowfield calculat ion employs the full axisymmetric Navier-Stokes equations, while indiv idual particle trajectories are computed by accounting for inertial, t hermophoretic and gravitational effects. The results of this simulatio n are analyzed to determine under what conditions particles greater th an 1 mum in diameter impact and thus contaminate the deposition substr ate. It is shown that particle size and injection location as well as flow direction (with or against gravity) and disk characteristics (tem perature and rotation rate) all play important roles here. The results for various parameter combinations are presented and discussed, as is the concept of a global type of particle contamination parameter.