VARIABLE CAPACITANCE SEMICONDUCTOR DEVICE AND CAPACITANCE CONTROL METHOD USING THE SAME, AND ELECTRONIC EQUIPMENT MOUNTING VARIABLE CAPACITANCE SEMICONDUCTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a variable capacitance semiconductor device having a high capacitance accumulated charge on a small surface area on a substrate.SOLUTION: A buried electrode part 20 on which an oxide film 24 is formed, is buried in an impurity range 26 formed in a semiconductor substrate part 10, an any DC voltage is applied between the buried electrode part 20 and the semiconductor substrate part 10 by a voltage application part 30, 32 to accumulate charge amount corresponding to the applied DC voltage on a charge accumulation part 40 formed inside the oxide film 24 and form a variable capacitance semiconductor device 100.SELECTED DRAWING: Figure 1