Method of manufacturing a semiconductor laser

Claim 1

A method of manufacturing a semiconductor laser, said method comprising the steps of: sequentially forming a first cladding layer having a first conductivity type, an active layer, a second cladding layer having a second conductivity type and a cap layer on a (100) plane of a semiconductor substrate having said first conductivity type to form a laminated structure for a semiconductor laser; forming a stripe-like mask made of an inorganic material and extending in a <011> direction with respect to said semiconductor substrate, etching said laminated structure from a surface thereof to said first cladding layer by using said mask as a direct anti-etching mask with a predetermined etchant, said predetermined etchant being selected so that etching rates of said cap layer and said second cladding layer on a (111)B plane are respectively lower than those of other crystal planes of said cap layer and said second cladding layer, said etchant etching said cap layer at a higher etching rate on the (111)B plane thereof than said second cladding layer on the (111)B plane thereof; forming a burying layer by an epitaxial growing method in a region from which said laminated structure has been removed by said etching step, using said mask as a selective growing mask; moving said mask and said cap layer; and forming a third cladding layer of said second conductivity type and a contact layer of said second conductivity type on said burying layer and said second cladding layer.

Claim 2

A method of manufacturing a semiconductor laser, said method comprising the steps of: sequentially forming a first cladding layer having a first conductivity type, an active layer, a second cladding layer having a second conductivity type and a cap layer on a (100) plane of a semiconductor substrate having said first conductivity type to form a laminated structure for a semiconductor laser; forming a stripe-like mask made of an inorganic material and extending in a <011> direction with respect to said semiconductor substrate, etching said laminated structure from a surface thereof to said first cladding layer by using said mask as a direct anti-etching mask with a predetermined etchant, said predetermined etchant being selected so that etching rates of said cap layer and said second cladding layer on a (111)B plane are respectively lower than those of other crystal planes of said cap layer and said second cladding layer, said etchant etching said cap layer at a higher etching rate on the (111)B plane thereof than said second cladding layer on the (111)B plane thereof; forming a burying layer by an epitaxial growing method in a region from which said laminated structure has been removed by said etching step, using said mask as a selective growing mask; moving said mask and said cap layer; and forming a third cladding layer of said second conductivity type and a contact layer of said second conductivity type on said burying layer and said second cladding layer.