| 摘要 |
PURPOSE:To ensure the protective capacity to the ratch-up in case the forward voltage is applied to the uni-conduction type semiconductor substrate from outside, by providing the reverse conducting input protective region and another deep reverse conducting region enclosing the protective region and then securing an electric connection between the deep region and the substrate. CONSTITUTION:P<->-type well region 4a and 4b are formed through diffusion and at one time on N-type semiconductor substrate 1 to be used for N-channel transistor Tr and the input protective device. Then N<+>-type region 3 is formed through diffusion to eliminate the parasitic effect on the substrate surface as well as to form the sfource and drain of N-channel MOS.Tr, and also input protective region 2 is formed through diffusion to be used as the input protective diode or the resistance. At the same time, P<+>-type region 2' is formed through diffusion within region 4a and 4b to eliminate the parasitic effect as well as to be used as the source and drain of P-channel MOS.Tr. After this, the gate SiO2 film is provided at the fixed region, and the input electrode, the gate connecting electrode plus earth electrodes 6-6'' are attached respectively. |
