| 摘要 |
PROBLEM TO BE SOLVED: To provide an electrode, which will not cause peel off and has a solder resistance which can adequately withstand mounting conditions, when a semiconductor light-receiving and a light-emitting element is mounted on a wiring board through solder dipping method. SOLUTION: An electrode for semiconductor light-receiving and light-emitting element consists of a first metal layer 22, which forms an ohmic junction with a semiconductor wiring board, a second metal layer 23 which is hardly eroded by a brazing metal, such as solder and moreover is comparatively good in wettability with solder, and a third metal layer 24 having good wettability with solder which are successively laminated on the surface of the wiring board. In this case, the thicknesses of the first, second and third metal layers are respectively set to a thickness of 0.3 μm or larger and 1.0 μm or smaller, a thickness of at least 0.3 μm or larger or a thickness 0.5 μm or larger and 1.5 μm or smaller. Moreover, it is desirable that the ratio of the thickness of the layer 23 to the thickness of the layer 22 and the ratio of the thickness of the layer 23 to the thickness of the layer 24 be optimized. |
