Abstract
A vacuum furnace using a molybdenum heater for use in pulling single crystals of germanium from a melt is described. It has a pulling rod with rotation two removable impurity adders a adjusting rod for crucible base and could be observed during the run through windows with shutters.
The vacuum system consisted of a 4″oil diffusion pump of the speed of 100l/sec and a 500l/min mechanical pump and the vacuum higher than 5×10-5mmHg was maintained during operation
