74 Crystal Growth and Evaluation of Silicon for VLSI and ULSI
with silicon coating on it. At higher temperatures, the vapor transport of iron from the test
samples is higher. Wafers exposed to graphite and silicon carbide–coated graphite have
higher iron concentrations than that of samples that were coated with silicon and silicon
carbide. Application of uniform coatings on all graphite components is an issue in this
case, particularly for varying silicon melt levels.
Experimental evaluations were carried out by Gilmore et al. [58] to study the impact
of graphite furnace parts on radial impurity distributions for the CZ-grown crystals. A
method was developed to examine the inuence of the furnace parts as a contamination
source during high-tempera ...