JPS5771165A - Semiconductor device - Google Patents

Abstract

PURPOSE:To prevent a variation in substrate electric potential accompanying a variation in electric potential of capacitor electrode and to stabilize an IC caontaining a delay circuit, a step-up circuit, and a step-down circuit by a method wherein a conductive laer forming constant electric potential is provided between the capacitor consisting of a plurality of opposed conductive layers and a substrate. CONSTITUTION:For example, as a capacitor element used for boost trap circuit and the like, conductive layers 10, 11 (or conductive layers 12, 13) such as Al or poly Si are oppositely arranged through an insulation layer on a P type substrate 1, for example. For example, N type diffusion regions 3, 4 are provided between the conductive layers forming these capacitor electrodes and the substrate 1 (or a separate metal layer 14 is provided on the substrate 1 through the insulation film) and these are grounded to shield the capacitor electrodes and substrate in electric potential. In this way, malfunction and the like by a variation in substrate electric potential such as other circuit, for example, RAM and the like can be prevented and the operation of IC having capacitor elements with a high capacitance value can be stabilized.