| 摘要 |
PURPOSE:To obtain the protective device for an MIS type semiconductor device having fast responding speed by forming a think tunnel barrier connected to the gate electrode of the MIS type semiconductor device. CONSTITUTION:A source 2 and a drain 3 are formed on the main surface of a P type Si substrate 1, a polycrystalline Si gate 5 is formed via the first dielectric film 4, the second dielectric film 6 becoming a tunnel barier film is further formed, an electrode 7 is formed thereon, is connected to the gate 5, and is connected to an input terminal 7a. The overvoltage input from the input terminal 7a is passed from the film 6 through the tunnel substrate 1 in the region 7 before it is transmitted to and filled in the gate region 5, thereby preventing the insulation breakdown of the film 4. |
