| 摘要 |
PURPOSE:To prevent an Au diffusion in forming an ohmic electrode with a three layer structure by forming a gold layer after titanium and platinum layers each having had an ohmic contact are formed. CONSTITUTION:After a semiconductor 7 is formed, a Ti layer 8a and a Pt layer 8b are sequentially covered on a contact layer 6 by an electro-beam evaporation. Then, a heat treatment is conducted in an electron furnace to establish an ohmic contact between the layer 6 and each of the layers 8a and 8b. Thereafter, an electrode P is formed on the reverse side surface of a substrate 1. Then, an Au layer 8c is covered on the Pt layer 8b by an ordinary electrolytic plating, completing to form an electrode 8. This laser has no Au in an active region 4a and has an excellent reliability. |
