METHOD FOR SETTING TEMPERATURE PROFILE OF PRESSURIZED HEATING VESSEL

摘要

PURPOSE:To set a desired temp. profile without changing the quantity of the heat to be supplied by changing the properties of the gas to be sealed into a pressurized heating vessel. CONSTITUTION:A gaseous mixture is sealed into the pressurized heating vessel having >=2 kinds of temp. zones; low temp. and high temp. in the growth, etc., of a semiconductor single crystal. The properties expressed by the relation between heat conductivity lambda and coefft. nu of dynamic viscosity which determine the quantity of heat radiation by the natural convection in the gas-sealed vessel are changed in this stage. For example, an inert gas such as Ar or Kr of which the value expressed by the equation is smaller than the value of air or gaseous nitrogen is used and the pressure of the gas to be sealed is changed, by which the desired temp. profile is set. The vessel is made smaller in size and lower in cost by the above-mentioned method without the need for providing a heat insulating member to the end of the temp. zone.