Analysis of critical parameters affecting the temperature uniformity during rapid thermal processing

In this work we examine the effect of various system and wafer parameters such as the flowing ambient, the spatial distribution of incident energy flux, the slip-free ring and doping density on temperature non-uniformity occurring during rapid thermal processing (RTP). The effect of using two inert ambients, i.e. argon and nitrogen, on temperature non-uniformity occurring during RTP cycle is studied in detail. The importance of dynamic lamp power control in providing time dependent spatial variation of incident energy flux as a measure to improve the temperature uniformity is also examined. Finally the simulation studies are also done in the presence of a slip-free ring. The nature of photon capture by the silicon wafer and the correlation between doping density and the steady state temperature for any given open loop condition is discussed in detail. This analysis has been done using an analytical tool developed by us based on simple 3-dimensional physical models depicting a typical rapid thermal cycle[1].