Optical semiconductor equipment

摘要

The prior art distributed feedback laser having an InGaAlAs active layer involves a problem that its laser characteristics are deteriorated at high temperature due to the high device resistance. According to the present invention, a ridge type laser is fabricated by: forming an InGaAlAs-MQW layer 104 on a n-type InP substrate 101; growing a p-type InGaAlAs-GRIN-SCH layer 105, a p-type InAlAs electron stopping layer 106 and a p-type grating layer 107 in this order on the InGaAlAs-MQW layer 104; forming a grating; and regrowing a p-type InP cladding layer 108 and a p-type InGaAs contact layer in this order. The concave depth of the grating is smaller than the thickness of the p-type grating layer 107.