Optimum Conditions for Baking of Indium

Abstract

Calculations of SiO partial pressure over an indium melt with dissolved silicon in a moist hydrogen atmosphere are reported. The results are given as a function of temperature, water vapor pressure, and concentration of silicon in the melt, both with and without SiO~ present. The influence of the total pressure in the baking system is considered, and the calculations indicate that by using a pressure lower than atmospheric, the efficiency of the baking should be significantly increased. The time constant of the baking process is, furthermore, shown to be critically dependent on water vapor partial pressure. These results should be valuable when one wants to find the optimum baking procedure to remove residual silicon from indium.