| 摘要 |
PURPOSE:To obtain stable oscillating lateral mode having a low oscillating thresold current, by providing a current path layer and a concave part. CONSTITUTION:By utilizing the difference in etching speeds based on the difference in compositions of GaAs layers 11 and 13, the concave part whose depth from the slant surface is about 0.2-0.5mum, is formed in a GaAs layer 12 at a slant stepped part. A positive voltage is applied to a P side electrode 21 and a negative voltage is applied to an N side electrode 22. Since the epitaxial layer 12 is of N type but the epitaxial layers 11 and 13 are of P type, the current is squeezed only into the N type GaAs layer 12 by P-N reverse bias and inputted into a rib shaped active region of an active layer 17. The light emission is obtained in said active region by recombination. When gain overcomes loss by the sufficient input current, the laser light is emitted at the active region. Said light is confined in said active region by the difference in the film thicknesses of clad layers 16 and 18 and the active layer 17 at both ends of the active region. Based on the confining action in the lateral direction of the light due to the difference in the film thicknesses, a stable fundamental mode is oscillated. |
