The semiconductor laser device has the lower clad layer, active layer,
upper clad layer, contact layer, the insulating film, and the positive
electrode sequentially formed on the semiconductor substrate. The upper
clad layer, the contact layer and the insulating film form the ridge. The
positive electrode covers the upper and side faces of the ridge. The
thickness of the positive electrode on the upper and side faces of the
ridge is preferably substantially the same and it is not less than 150 nm.
