An n-GaAs buffer layer, an n-AlGaAs lower cladding layer, an n- or i-InGaP lower
optical waveguide layer, an InGaAsP quantum cell active layer, a p- or i-InGaP
upper optical waveguide layer, a p-AlGaAs first upper cladding layer, a p- or i-InGaP
etch-stopping layer, a p-AlGaAs second upper cladding layer, and a p-GaAs contact
layer, are grown upon an n-GaAs substrate. A photoresist is coated on the wafer,
and two grooves are formed by etching. Then, the photoresist on the perimeter of
the device is removed and the contact layer is selectively etched. Next, the photoresist
is lifted off. A SiO2 film is formed on the entire surface. After a
window is formed in a portion of the SiO2 film corresponding to a ridge
portion, a p-electrode is formed on a region of the SiO2 film other
than the device perimeter.
