Patent ID: 7746910

Claim:
A semiconductor laser diode device comprising: a semiconductor substrate comprised of a first conductivity type semiconductor, and including a first surface, and a second surface as a side opposite the first surface; a multiple epitaxial layer including sequentially formed layers of at least a first conductive cladding layer, an active layer, a second conductive cladding layer and second conductive contact layer on the first surface of the semiconductor substrate; a ridge structure formed by selectively etching from the upper surface of the second conductive contact layer to a specified depth on the second conductive cladding layer, and extending in a first direction in a stripe shape extending between one pair of facets opposite each other on the semiconductor substrate along first and second end edges, respectively, of the semiconductor substrate; an insulating layer formed over the first surface side of the semiconductor substrate on a section from a side surface of the ridge to the periphery of the semiconductor substrate; a second electrode formed over the insulating layer over the second conductive contact layer of the ridge, and a first electrode formed on the second surface of the semiconductor substrate, wherein the semiconductor substrate contains bandpass energy serving as an absorption layer for light on the emission wavelength of the active layer, or the refractive index value for all semiconductor layers between the active layer and the semiconductor substrate is larger than the semiconductor substrate refractive index value, wherein grooves are formed on both sides at one end of the ridge, said grooves extending along the first end edge of the substrate in a second direction which is substantially perpendicular to the first direction in which the ridge extends, and from the second cladding layer separated a specified distance from a side edge of the ridge to the side of the active layer, and at a depth from the second conductive cladding layer exceeding the active layer, and wherein the groove is covered by an insulating layer.