Halbleiterlaser mit verteilter Rückkopplung

A distributed feedback semiconductor laser and a method of manufacture includes first and second clad layers having predetermined refractive indexes that are formed on a semiconductor substrate (310). A guide layer (350) propagates light between the first and second clad layers (320,380). An oscillating active layer (360) oscillates light at a predetermined wavelength and an amplifying active layer (370) amplifies the light with a predetermined gain between the first clad layer and the guide layer. The distributed feedback semiconductor laser is divided into a laser oscillation section (450) including the oscillating active layer and a laser amplification section (460) including the amplifying active layer. First and second gratings (330,340) are formed on the lower surface of the guide layer in the laser oscillation section and in the laser amplification section, respectively.