Compound semiconductor device manufacturing method

A compound semiconductor device manufacturing method comprising the steps of:

• depositing a zinc diffusion film comprising zinc oxide and silicon oxide wherein zinc oxide is present in an amount of 70 wt % or more as a diffusion source, on a compound semiconductor layer having a multi-layered structure, said semiconductor layer constitutes a semiconductor laser, and
• diffusing zinc from said zinc diffusion film into said compound semiconductor layer by annealing,
• wherein said compound semiconductor layer is formed by the steps comprising,
• forming a first conductivity type cladding layer on a substrate that has an inclined plane and flat faces on both sides of said inclined plane,
• forming an active layer on said first conductivity type cladding layer,
• forming a lower portion of a second conductivity type cladding layer on said active layer,
• forming an intermediate layer portion of said second conductivity type cladding layer on a region that is substantially parallel with said inclined plane of said substrate and also forming first conductivity type current strangulated layers on regions that are parallel with flat surfaces of said substrate, by growing compound semiconductor on said lower portion of said second conductivity type cladding layer while doping a first conductivity type dopant and a second conductivity type dopant alternatively, and
• forming an upper portion of said second conductivity type cladding layer on said first conductivity type current strangulated layers and said intermediate portion of said second conductivity type cladding layer,
• whereby said zinc from said zinc diffusion film is diffused to a position that is lower than said active layer by controlling an annealing time and a temperature.