| 摘要 |
PURPOSE:To enable to upgrade the yield by a method wherein an LD and a bipolar transistor are arranged in vertical type by using the bipolar transistor for a driving element to suppress the loss of electric power less, lessen the increase of Ith and reduce the area of the element. CONSTITUTION:A four elements layer 32 of InGaAsP is epitaxially grown on an N type InP substrate 31. After that, on the four elements layer 32 is epitaxially grown a P type InP layer 33 called a P-clad layer and an N type InP layer 34 is epitaxially grown on the P-clad layer 33. And then, impurities of Zn or Cd, etc., are selectively diffused or implanted in the N type InP layer 34 for forming a P type InP layer 35. At this time, the N type InP layer 34 being interposed between the P type InP layer 35 and the InP layer 33 is turned into the base layer and the width thereof becomes the base width. The four elements layer 32 being interposed between the N type InP substrate 31 and the P type InP layer 33 forms a double junction of a different kind and shuts the carriers in by current from the emitter of the P type InP layer 35 located right over the layer 32 to generate the laser luminescense. |
