Semiconductor integrated circuit device

Abstract

A semiconductor integrated circuit device includes in a P-type well region containing a memory substrate a array section in which dynamic memory cells are arranged in a matrix. The P-type well region is fed with a back bias voltage whose absolute value is reduced so as to be the most suitable for the refresh characteristics. Also included is a P-well region wherein there are formed N-channel MOSFETs of a peripheral circuit this P-well region is fed with a back bias voltage whose absolute value is smaller than that of the potential fed to the P-type well of the memory array section, considering the high-speed operation. A P-type well section, wherein there is formed are N-channel MOSFETs of an input circuit or an output circuit connected with external terminals, is fed with a back bias voltage whose absolute value is made large considering an undershoot voltage. The P-type well region provided with the memory array section is fed with a requisite minimum back bias voltage. Accordingly, the P-type well region provided with the input circuit or the output circuit corresponding to the external terminals is fed with the back bias voltage to provide a measure of protection against undershoot, while the refresh characteristics are improved by reducing the leakage current between the source/drain region connected with a capacitor and the P-type well, to thereby raise the operation speed of the peripheral circuit can be raised.