MOS CAPACITOR AND SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a MOS capacitor and the integrated circuit device of a voltage controlled oscillator(VCO) that can vary a wide-range of frequency using the MOS capacitor and can be easily integrated. SOLUTION: In a variable-capacity capacitor, a MOS capacitor is subjected to VCO configuration, where it has a conductor layer 53 that becomes one electrode via a capacity insulation film 54 on a first conductivity type semiconductor region 51 that becomes the other electrode and has a second conductivity type impurity region 52 near a surface close to a region that opposes the conductor layer 53 of the first-conduction-type semiconductor substrate 51.