DETERMINATION OF OPTIMUM SATURATION TIME IN CHLORIDE VPE

摘要

PURPOSE:To easily and accurately determine the optimum saturation time in chloride VPE, by supplying a chloride of group V element and H2 to a vacuum vessel containing a group III element and monitoring the amount of the group V element contained in exhaust. CONSTITUTION:A vacuum vessel 1 containing a group III element 2 (e.g. In) is supplied with a gaseous mixture of a chloride of a group III element (e.g. PCl3) and H2 through an inlet port 3 and with H2 gas through an inlet port 4. A part of exhaust is supplied to an analyzer 6 branched from an exhaust pipe 5 and the amount of the group V element existing in the exhaust is monitored. When the surface of the group III element 2 is covered with a III-V compound semiconductor to reach the optimum saturation time, the group V element is released in the exhaust. The optimum saturation time is determined by the detection of the group V element in the exhaust by the analyzer 6.