| 摘要 |
PURPOSE:To ensure operation at high speed and the high reliability of performance characteristics by forming a beam extracting window having a diameter larger than the diameter of an operating region and smaller than the diameter of a high impurity concentration region to the upper section of the operating region and shaping a first electrode layer on a current stopping layer and a second electrode layer on another substrate surface. CONSTITUTION:An N type first clad layer 3, a P type first active layer 4, an N type second active layer 5 and a P type second clad layer 6 are grown on one substrate surface 1a of an N type GaAs substrate 1 in an epitaxial manner in the liquid phase or the vapor phase in succession. A P side electrode as a first electrode layer 10 is applied onto a cap layer 7b, and etched selectively by an ammonia-hydrogen peroxide group etching liquid together with the cap layer 7b on the lower side to bore circular windows 8b and 8a, thus forming a window 8 for extracting beams or receiving beams. The diameter of the window 8 is made larger than that of an operating region 2 and smaller than that of a high impurity concentration region. Since machining is not required for preparing the window, there is no possiblity of the deterioration of the characteristics of an element such as output lowering due to mechanical strain, thus improving the reliability of characteristics. |
