| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device which comprises a guard ring which can eliminate the need for exclusive reference potential wiring having a great effect of shielding substrate noise. SOLUTION: An insulating film 8 is provided in a region around a circuit region 3 on a P type silicon substrate 1, and a frame-shaped electrode 9 is provided to surround the circuit region 3. A region in the surface of the P type silicon substrate 1 under the electrode 9 is a impurity-nondoped region. A positive power potential V<SB>G</SB>is applied to the electrode 9, so that the region in the surface of the substrate 1 under the electrode 9 is formed as a depletion layer 10. As a result, substrate noise can be shielded. COPYRIGHT: (C)2005,JPO&NCIPI |
