| 摘要 |
PURPOSE:To simplify a processing step by forming at the same time a plurality of insulation films having different thickness on the surface of an identical semiconductor area. CONSTITUTION:An oxide film 2 formed on the surface of n type region is removed selectively to form a window 3. Subsequently, an impurity is diffused selectively from the window 3 to form an n<+> type region 4 of high implsity density to be used for one electrode of MIS capacitor. In such a process, the surface the window 3 is covered with oxide film 2A. Subsequently, the films 2A and 2 are removed selectively to form windows 9, 5. Subsequently, an oxide film 2C is formed on the surface of the window 9 and an oxide film 2D is formed on the surface of the wondow 5. In this case, the film 2C is formed thick in accordance with difference of the impurity density in the regions 1 and 4. Subsequently, a boron ion is implanted into the region 1 through the film 2D to form a p type region 6. Subsequently, the film 2C is removed selectively to form a window and an elctrode 7 is formed through the window and an electrode 8 is formed on the film 2C. According to such a constitution, an IC including a resistor and MIS structure capacitor, formed therein can be obtained. |
