Simulation of a polysilicon LPCVD reactor Fluid-dynamics and Error Analysis

The deposition of polysilicon is numerically simulated with a model that computes the fluid flow, transport coefficients and surface chemistry inside the LPCVD reactor. The results exhibit relatively small gas recirculations as a result of the temperature gradients in the empty inlet area and in the heating zone. Comparing simulations with and without reactive surfaces, inter-wafer recirculations near non-reactive waferedges are eliminated at reactive wafer. A comparison of four deposition models and an error analysis leads to the conclusion, that no complex chemical models are necessary as long as the uncertainty of the activation energy is by far the largest source of error.