VARIABLE CAPACITY DIODE, SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a variable capacity diode of which a capacity change ratio is great, and a semiconductor device comprising the relevant variable capacity diode. SOLUTION: On a surface of a semiconductor substrate 1, there are formed a P-layer 7 and N+layer 8 which constitute a variable capacity diode, and a source layer 10 and a drain layer 11 which constitute an MOS transistor. Next, a layer insulating film 12 is formed which includes contact holes 13, 14 exposing the N+layer 8, the source layer 10 and the drain layer 11. Then, a resist layer 15 is formed which covers the exposed N+layer 8 in the contact hole 13. Furthermore, an N++layer 16 is formed by implanting a high-concentration N-type impurity ion through the contact hole 14 into the source layer 10 and the drain layer 11. In such a case, the impurity ion is prevented from being implanted into the N+layer 8. Afterwards, a cathode electrode 17 and metal wiring 18 are formed within the contact holes 13, 14. COPYRIGHT: (C)2009,JPO&INPIT