| 摘要 |
PURPOSE:To prevent a resistance value of poly-Si resistor to change in accordance with a potential of lower substrate part by forming impurity diffusion layer to the lower semiconductor substrate region of poly-Si resistor and fixing a potential of such impurity diffusion layer to a constant. CONSTITUTION:An impurity layer 21 is formed in the region including the lower part of the poly-Si resistor 3 forming region at the surface of semiconductor substrate 1. An insulation film 2 is also formed on this substrate 1 and a poly- Si resistor 3 is formed at a part of the upper region of layer 21 on the film 2. In a semiconductor device of such constitution, for example, the substrate 1 is fixed to the ground potential and the layer 21 is fixed to the same potential as the substrate 1. Thereby, potential does not change at the lower part of resistor 3 and therefore any effect is not exerted on the resistance value of resistor 3. |
