| 摘要 |
PURPOSE:To extract laser beams modulated at high speed, to miniaturize the device, to improve reliability and to reduce cost by flowing minute signal currents through a transistor element for modulation because a transistor amplifier for driving a laser is made contain into the same element. CONSTITUTION:An SiO2 film is formed onto a wafer through a sputtering method, a P type impurity is diffused up to depth reaching a semiconductor layer 4, and a first conductive type (P type) semiconductor region 11 is shaped. An ohmic electrode 15 for an N type semiconductor is formed and ohmic electrodes 13, 14 for a P type semiconductor to the surfaces of the P type semiconductor region 11 and a P type semiconductor substrate 10 respectively. A resonator at a proper interval is shaped through a means, such as cleavage, etching, etc. Accordingly, one semiconductor laser element is formed by semiconductor layers 1, 2, 3 and one NPN transistor by semiconductor layers 3, 4, 5. |
