| 摘要 |
PURPOSE:To form a highly accurate resistor element in a minute region, by forming a first groove, thereafter introducing an opposite conductivity type impurities with respect to a semiconductor substrate in the inner surface of the first groove, and forming a resistor region. CONSTITUTION:An oxide film 2 is formed on the surface of an N-type semiconductor substrate 1. A first groove 3 is formed by anisotropic etching. Then, a P-type resistor region 4 is formed on the inner surface of the groove 3. Then an oxide film 5 as a dielectric film is formed on the inner surface of the first groove 3. Thereafter, the first groove 3 is filled with a polycrystalline semiconductor 6, which does not include impurities. Thereafter, three second grooves 7 (7a, 7b and 7c) are formed in order to trim the resistance region of the first groove 3. Since the resistor resion 4 is formed by introducing P-type impurites in the substrate by a diffusing method or an ion implanting method, the highly accurate resistor element is obtained. Since the resistor region 4 is formed by utilizing the side wall and the bottom wall of the groove, the resistor element can be provided in the minute region. |
