Patent ID: 7616674
Filing Date: 2009-11-10
Classification: B82Y,H01S

Abstract:
1. A semiconductor laser diode array comprising: a lower semiconductor laser diode chip having a dual structure including a lower substrate, a first laser generating region having a first surface disposed on the lower substrate, and a second laser generating region having a first surface disposed on the lower substrate, the second laser generating region being entirely separated from the first laser generating region, and the first and second laser generating regions each having a respective second surface opposed to the first surface thereof, respectively; an upper semiconductor laser diode chip having a dual structure including an upper substrate, a third laser generating region having a first surface disposed on the upper substrate, and a fourth laser generating region having a first surface disposed on the upper substrate, the fourth laser generating region being entirely separated from the third laser generating region, and the third and fourth laser generating regions each having a respective second surface opposed to the first surface thereof, respectively; and an electrode unit electrically connecting the first through fourth laser generating regions to the outside, wherein the second surfaces of the first and second laser generating regions are vertically bonded to the second surfaces of the third and fourth laser generating regions, respectively, so that first through fourth light-emitting points respectively provided in the first through fourth laser generating regions from which laser beams are emitted are arranged in a two-dimensional fashion, wherein the electrode unit comprises: a first electrode of a first conductivity type formed on a stepped portion of the first laser generating region proximate to the first surface of the first laser generating region; a second electrode of the first conductivity type formed on a stepped portion of the second laser generating region proximate to the first surface of the second laser generating region; a third electrode of a second conductivity type formed on the respective second surfaces of the first and third laser generating regions, the second conductivity type being opposite to the first conductivity type; a fourth electrode of the second conductivity type formed on the respective second surfaces of the second and fourth laser generating regions; and a fifth electrode of the first conductivity type formed on a first surface of the upper substrate opposite to a second surface of the upper substrate on which the respective first surfaces of the third and fourth laser generating regions are disposed, wherein the first through fifth electrodes are configured to be independently addressable so as to independently drive the first through fourth laser generating regions, and wherein the first laser generating region includes a first n-contact layer, a first n-clad layer, a first active layer, a first p-clad layer, a first p-metal layer and a first bonding metal layer sequentially formed on the lower substrate; the second laser generating region includes a second n-contact layer, a second n-clad layer, a second active layer, a second p-clad layer, a second p-metal layer and a second bonding metal layer sequentially formed on the lower substrate; the third laser generating region includes a third n-clad layer, a third active layer, a third p-clad layer, a third p-metal layer and a third bonding metal layer sequentially formed on the second surface of the upper substrate; the fourth laser generating region includes a fourth n-clad layer, a fourth active layer, a fourth p-clad layer, a fourth p-metal layer and a fourth bonding metal layer sequentially formed on the second surface of the upper substrate, the first bonding metal layer in the first laser generating region is attached to the third bonding metal layer in the third laser generating region; and the second bonding metal layer in the second laser generating region is attached to the fourth bonding metal layer in the fourth laser generating region.