| 摘要 |
PURPOSE:To enable injection currents to be collected in an effective active region by a method wherein the first and second semiconductor layers different in the conductive type are formed on the active layer, and an impurity diffusion limiting layer is selectively formed on a step at an end of the semiconductor layer on the second semiconductor. CONSTITUTION:The step T is formed on the N type GaAs substrate 17, and an N type Ga1-XAlXAs clad layer 18 and a nondoped Ga1-YAlYAs active layer 19 are formed on the substrate 17 formed with the step. Additionally, on the layer 19 are formed a P type Ga1-XAlXAs clad layer 20, and N type GaAs layer 21 and an N type Ga1-ZAlZAs layer 22. Then, the layer 22 other than those extending from a bent part below the step T to a part right above the flat outside the step T of the layer 19 is removed to form an Si3N4 film capable of preventing the impurity diffusion on the crystalized surface, and further, a strip-shaped window is opened to be formed at the part with a zinc diffusion region 24. At this time, the diffusion is made deepest right under the part where the layer 21 is exposed and stopped at a time when the diffusion surface reaches the layer 20. Subsequently, the film 23 and the layer 22 are removed to permit a metallic film 25 for a P type ohmic electrode to be formed on the layer 21. |
