Experimental and Theoretical Investigation of Thermodynamic and Transport Phenomena in Polysilicon and Silicon Nitride CVD

Abstract

The performance of chemical vapor deposition (CVD) reactors is strongly dependent on fluid flow, heat transport and mass transport. In this work, the deposition of polysilicon in a LPCVD batch reactor is modeled by using the local thermochemical equilibrium approach coupled with transport effects. The focus is on understanding how the interplay of flow and kinetic factors influences deposition in a CVD reactor. Experiments were conducted to study the effect of temperature on deposition rate. Comparisons between the modeling and experimental results were used to obtain an insight into the parameters affecting deposition. PECVD reactors are being increasingly used in the industry for carrying out deposition at low temperatures. A review is presented of the challenges faced in PECVD modeling and the approaches that could be followed. An empirical model for PECVD deposition of silicon nitride deposition is also presented.