Semiconductor device and method for manufacturing semiconductor device

The semiconductor device according to the present invention comprises: a main part which includes a semiconductor substrate, a first type first cladding layer that is provided on the semiconductor substrate and is one of n-type or p-type, an active layer provided on the first cladding layer, and a second type second cladding layer that is provided on the active layer and is the other of n-type or p-type, the main part having a flat part and a mesa part including the active layer formed therein; and a first embedded layer which is a second type and covers the top surface of the flat part and the side surfaces of the mesa part. The first embedded layer has a projecting part on the top surface of a portion that is provided in a region of the top surface of the flat part from the boundary between the mesa part and the flat part to the height of the mesa part.