| 摘要 |
PURPOSE:To improve reliability of an input protector which employs polycrystalline Si as a connecting wiring between the external lead electrode for input and the gate electrode of the input transistor, by providing a clamping element to clamp an excess voltage adjacently to the lead electrode. CONSTITUTION:An external lead electrode 25 for input and a transistor having a source region 31, a drain region 31' and a gate electrode 30 are connected through a diffused wiring layer 29 by using an N type polycrystalline Si wiring layer 28. In other words, a P type Si substrate 35 is coated with a thick oxide film 33, openings are made and the diffused wiring layer 29 andf the external lead electrode 25 for input are connected by using the polycrystalline Si wiring 28, which is protected by an oxide film 32. In said constitution, at the electrode 25 portion an N type diffused layer 34 to clamp an excess voltage is provided in the substrate 35 by using a through hole 26, and after the wiring 28 is brought into contact with the layer 34, the lead electrode 25 is attached to the wiring 28 through a through hole 24. |
