Abstract: A method of cleaving a semiconductor wafer is disclosed which includes coating a first photoresist on a front surface of a semiconductor wafer having a plurality of semiconductor laser elements formed on the semiconductor wafer, patterning the first photoresist so as to form guide mark patterns for cleaving, coating a second photoresist on a rear surface of the semiconductor wafer, removing an edge part located at the guide mark patterns for cleaving of the second photoresist, etching through the semiconductor wafer to form guide marks using the patterned first and second photoresists as masks, patterning the second photoresist to form stripe patterns in the rear surface, etching the rear surface of the semiconductor wafer so as to form V-shaped or dovetail shaped grooves, removing the first photoresist and the second photoresist, and cleaving the semiconductor wafer along the V-shaped or dovetail shaped grooves into bars, each bar being a semiconductor laser.

Abstract: A semiconductor laser including a compound semiconductor substrate of an n-type, a semiconductor laser chip region defined at a center portion of an upper portion of the compound semiconductor substrate and provided at its front and rear surfaces with mirror surfaces for oscillating laser beams, and a pair of guide regions defined at opposite sides of the chip region, respectively, to be in contact with the semiconductor laser chip region. The chip region has a shape of a hexahedron. Together with the front and rear surfaces of the chip region, the guide regions define a cavity for coupling the chip region with external elements at the compound semiconductor substrate. The semiconductor laser also includes a first electrode formed over the chip region and guide regions and adapted to receive an electric power for generating laser beams and a second electrode formed beneath the semiconductor substrate and adapted to receive the electric power for generating laser beams, together with the first electrode.

Abstract: A semiconductor laser diode includes a semiconductor substrate, an active layer having a double hetero structure formed on the semiconductor substrate, a first quantum well layer formed between the active layer and the current confinement layer, a second quantum well layer formed on the active layer corresponding to the current injection groove, and a clad layer having its flat surface formed on the current injection groove and the current confinement layer. A method for manufacturing the semiconductor laser diode includes the steps of forming an active layer having a double hetero structure on the semiconductor substrate, selectively forming a current confinement layer on the active layer to form a current injection groove, forming a clad layer having its flat surface on the current injection groove and the current confinement layer.

Abstract: A semiconductor laser including a compound semiconductor substrate of an n-type, a semiconductor laser chip region defined at a center portion of an upper portion of the compound semiconductor substrate and provided at its front and rear surfaces with mirror surfaces for oscillating laser beams, and a pair of guide regions defined at opposite sides of the chip region, respectively, to be in contact with the semiconductor laser chip region. The chip region has a shape of a hexahedron. Together with the front and rear surfaces of the chip region, the guide regions define a cavity for coupling the chip region with external elements at the compound semiconductor substrate. The semiconductor laser also includes a first electrode formed over the chip region and guide regions and adapted to receive an electric power for generating laser beams and a second electrode formed beneath the semiconductor substrate and adapted to receive the electric power for generating laser beams, together with the first electrode.