PURPOSE: To remove the defect of a buried boundary and the influence of an impurity or the like by forming a pattern of InGaAsP at the uppermost layer, and selectively growing the InGaAsP thereon without exposing the boundary of the buried portion.
CONSTITUTION: An N+ type InP layer 10 and an N- type InGaAs layer 11 are epitaxially grown on a memi-insulating InP substrate 1. Then, a pattern 12 is formed in the desired pattern by etching the layers 10, 11. Then, to bury the pattern 12, an N- type InP layer 13 is epitaxially grown at 630°C of growing temperature. At this time, the layer 13 is grown 0.2μm thick on the exposed substrate portion, the layer 11 is dissolved in InP solution on the pattern 12 to form a flat buried surface. Further, an N- type InGaAs layer 2 is continuous ly grown 2μm thick. In the thus obtained structure, a photodetector is formed in a Pin structure, a series resistance component is reduced by implanting the layer 10 to readily accelerate the speed.
ISHINO MASATO
SASAI YOICHI
OGURA MOTOTSUGU
