| 摘要 |
PURPOSE:To obtain the device having a capacitor which maintains a fixed capacitance value irrespective of a threshold value by a method wherein a conductor layer is provided on the N-layer on the surface of a P type Si substrate. CONSTITUTION:A field oxide film 12, a gate oxide film 13, a polycrystalline Si gate electrode 14 and an N type source and drain layer 15 are provided on a P type Si substrare 11 using the method hithertofore in use. Besides, a deep N layer 16 is provided adjoining to the source and drain region 15. Subsequently, a source and drain terminal 8 and a gate terminal 19 are installed using the method hithertofore in use. According to this constitution, a capacitance having the gate electrode 14 and the N layer 16 as opposed electrodes, is obtained using the oxide film as a dielectric. As the N layer is formed deeply, a threshold value becomes below negative by several V, the range of performance of gate voltage is widened and the semiconductor device with a capacitor having a fixed capacitance value at all times can be obtained irrespective of the threshold value. |
