| US 7,460,575 B2 | ||
| Semiconductor laser and the method for manufacturing the same | ||
| Takahiko Kawahara, Yokohama (Japan); and Nobuyuki Ikoma, Yokohama (Japan) | ||
| Assigned to Sumitomo Electric Industries, Ltd., Osaka (Japan) | ||
| Filed on Jan. 04, 2006, as Appl. No. 11/324,800. | ||
| Claims priority of application No. 2005-000952 (JP), filed on Jan. 05, 2005. | ||
| Prior Publication US 2006/0159145 A1, Jul. 20, 2006 | ||
| Int. Cl. H01S 5/00 (2006.01) | ||
| U.S. Cl. 372—50.11 [372/50.1] | 5 Claims |
| 1. A semiconductor laser diode, comprising:
a semiconductor substrate having an undulation for a feedback grating;
an intermediate layer disposed on the semiconductor substrate and having the same undulation as the substrate;
a lower separated confinement layer disposed on the intermediate layer, the lower separated confinement layer filling valleys
of the undulation of the semiconductor substrate, a top surface of the lower separated confinement layer being substantially
flat, the lower separated confinement layer having a refractive index different from a refractive index of the substrate;
an active layer disposed on the lower separated confinement layer, the active layer generating the light diffracted by the
undulation in the substrate; and
an upper separated confinement layer disposed on the active layer,
wherein the semiconductor substrate, the intermediate layer, and the lower separated confinement layer are n-type InP, AlInAsP,
and AlGaInAs, respectively,
wherein the intermediate layer relaxes a band discontinuity between the lower separated confinement layer and the semiconductor
substrate; and
wherein the substrate, the intermediate layer and the lower separated confinement layer forms the feedback grating.
|