| 摘要 |
PURPOSE:To obtain a highly relable semiconductor device by prevent variations in the resistance value without higher concentration of the impurity surface of a poly Si resistance layer. CONSTITUTION:A field oxide film 22 is formed on a p type Si substrate 21 while a wiring 25 and a gate electrode 24 are formed on a gate oxide film 23 with doped poly Si to make n<+> layers 26 and 27. A CVD SiO2 28 is laid and etched 29 to form a poly Si resistance layer 30. Then, a doped poly si pattern 32 is provided partly on the top of the resistance layer 30 throuth the CVD SiO2 31. Finally, a protective film 33 is entirely provided to make an Al wiring and thus, MOS type RAM with a poly Si load resistance is completed. In this arrangement, electric charge in the seal resin or the SiO2 is retained or polarized on the surface of the poly Si 32. Consequently, the layer 32 acts as a shield to the poly Si 30 thereunder thereby preventing the formation of an inversion layer and depletion layer on the surface of the layer 30. This checks variations in the apparent resistance value to improve the reliability. |
