| 摘要 |
PURPOSE:To prevent the gate breakdown of FET of a shallow diffused layer by a method wherein an impurity-diffused layer inserted and connected between a semiconductor element and input/output terminals is made deeper than the diffused layer of the element. CONSTITUTION:An SiO2 film 5 is provided on an Si substrate 4, a gate oxide film 8 and a poly Si gate are formed, and a source 7, a drain 6 and a resistance layer 15a are formed by implanting As ions to the depth of 0.4mum. Then, a mask being renewed, P ions are implanted to the depth of 0.6-0.8mum to form a diffused layer 15 for resistance. Since the diffused layer 15 is formed sufficiently deep in this constitution, a curvature 16 is made large, no concentration of electric fields is thereby caused, and junction capacitance is also increased. Accordingly, an overvoltage or a high-voltage pulse caused by static electricity, which is applied to a pad 1, is damped enough by the resistance layer and thus causes no breakdown of the diffused layer 15. The electrostatic resistance of 100V or above can be obtained only by an increase in junction capacitance. |
