US 20040047379A1
(19) United States
(12) Patent Application Publication (io) Pub. No.: US 2004/0047379 Al
Kitamura (43) Pub. Date: Mar. 11,2004
(54) SEMICONDUCTOR LASER DEVICE
(76) Inventor: Tomoyuki Kitamura, Kanagawa (JP)
Correspondence Address:
RADER FISHMAN & GRAUER PLLC
LION BUILDING
1233 20TH STREET N.W., SUITE 501
WASHINGTON, DC 20036 (US)
(21) Appl. No.: 10/446,184
(22) Filed: May 28, 2003
(30) Foreign Application Priority Data
May 29, 2002 (JP) P2002-155508
Publication Classification (51) Int. CI.7 H01S 5/00
(57) ABSTRACT
A broad area semiconductor laser device having an NFP with top hat shaped profiles for the P wave and the S wave, which result Irom polarized beam splitting of the emitted light, is provided. The broad area semiconductor laser device of the present invention has the same structure as the broad area semiconductor laser device of the prior art, except that the composition of an etch stop layer is different. The semiconductor laser device includes an n-Al0 5Ga0 5As first clad layer; an active layer including an AlGaAs optical guide layer and an AlGaAs quantum well layer; a 0.3 fim thick p-Al05Ga05As lower second clad layer; an Al0 7Ga0 3As etch stop layer; a p-Al0 5Ga0 5As upper second clad layer; and a p-GaAs contact layer, which form a laminated structure on top of an n-GaAs substrate.
