LIQUID PHASE EPITAXIAL GROWTH METHOD

PURPOSE:To prevent thermal deterioration and contamination of substrate by releasing impurity gas from vaporization source solution of V group element and thereafter placing the vaporization gas sent from the vaporization source solution in contact with a substrate. CONSTITUTION:A substrate 13 is covered with a substrate protection plate 16 for about 20min at a temperature of about 350 deg.C and impurity gas is released from phosphorus vaporization source solution. During this period, the substrate 13 is protected by the substrate protection plate 16 and is not subjected to thermal deterioration. A slider 12 is slid for raising temperature. The substrate is held for about 40min at a temperature of 620 deg.C and the raw material 14 is perfectly dissolved as the growth solution. In this process, the phosphorus vapor is induced onto the InP substrate 13 from the phosphorus vaporization source solution and a high phosphorus vapor pressure is applied thereto. Thereby, thermal deterioration can be prevented. Thereafter, the substrate is cooled, growth starts at a temperature of 600 deg.C, the first InP layer and InGaAsP layer are caused to grow and the second InP layer is then caused to grow.