Patent ID: RE41643

Claim:
A semiconductor laser diode comprising: a body of a semiconductor material having therein a waveguide region which is not intentionally doped and which is of a material which substantially confines photons therein and allows the flow of photons therealong; means within the waveguide region for generating an optical mode of photons; and a clad region on each side of the waveguide region, the clad regions being at least partially doped to be of opposite conductivity type; wherein: said photon generating means being is thinner than the thickness of the waveguide region and being is spaced from the clad layers regions ; the thickness of the waveguide region and the composition of the waveguide and clad regions being are such that an overlapping of the optical mode generated in the waveguide region into the clad regions is not greater than about 5% ; the waveguide region is of a thickness of at least 500 nanometers; and the waveguide region has a doping level of no greater than 5 × 10 16 /cm 3 .