| 摘要 |
PURPOSE:To improve joining strength of a substrate onto a pad, by providing a joining pad directly on an SiO2 membrane by using a wiring material. CONSTITUTION:A base emitter layer is formed on an Si substrate 1. As for the emitter layer, the SiO2 membrane 4 is provided with an opening, Pt is attached by soldering to selectively form Pt-Si layer 6, and a 2-layer wiring for Mo 7 and Al 8 is provided. By covering with SiO2 10 and selectively providing openings 11 and 10a, an Al second wiring 12a and a pad 12a are provided. As the Al pad is strongly joined to the SiO2 membrane 4, it can be prevented from exfoliation at the time of supersonic joining, and this becomes furthermore effective when a thermal oxide membrane is used in particular. In this mechanism, possibility of exfoliation can be reduced to approximately 1% of that of a conventional Al-Mo dual structure. |
