HALBLEITERBAUELEMENT ZUM SCHUETZEN EINER ELEKTROSTATISCHEN SPANNUNG

摘要

A semiconductor device employs an NMOS transistor 9, 11, 45 connected between a voltage source line 5. Vcc and ground voltage line 7, Vss in parallel with an internal circuit 41 so as to discharge any electrostatic voltage through the NMOS transistor to ground. The NMOS transistor 45 is designed to perform breakdown operation at a lower voltage than that of a transistor of the internal circuit 41, so that when the voltage of the voltage source line Vcc is increased by the voltage of the electrostatic voltage, the NMOS transistor works first. A diffusion region 9 forms the drain and source of the NMOS transistor and a polysilicon line 11 forms the gate. In another arrangement, the source and drain diffusions are separated and pairs of contacts are applied to each region. <IMAGE>