| 摘要 |
PURPOSE:To enable to provide a semiconductor laser having low threshold current and to reduce the leakage of carrier by forming a wedge range in the band diagram of an active layer. CONSTITUTION:An n type Ga0.7Al0.3As clad layer 22, an undoped Ga1-xAxAs (0<=x<=0.3) active layer 21, a P type Ga0.7Al0.3As clad layer 23 and a P<+> type GaAs cap layer 24 are sequentially grown by an organic metal vapor growing method on a gallium arsenide substrate 25. At this time the active layer 21 is formed in a thickness not more than 1mum, the composition of aluminum is gradually varied to be set to 0 at the center of the active layer and to 0.3 at the part which is contacted with the clad layers of both sides. A wafer is attached to an insulating film 26, a pattern is formed to the film in a stripe shape, and a P type side electrode 27 and an n type side electrode 28 are formed by depositing. When a resonator is fored due to cleavage in a vertical direction from the wafer to the stripe, a laser oscillation can be observed. The threshold current depends upon the thickness of the active layer, and when the thickness becomes not more than 1mum, it becomes the value equivalent to or not more than the value of the laser with the normal oxidized film stripe electrode. |
