Semiconductor device and method of checking semiconductor storage device

Abstract

It is an object to obtain a semiconductor device having a circuit for CBCM (Charge Based Capacitance Measurement) which can measure a capacitance value with high precision. An MOS transistor constituting a circuit for CBCM has the following structure. More specifically, source-drain regions () and (') are selectively formed in a surface of a body region (), and extension regions () and (′) are extended from tip portions of the source-drain regions () and (′) opposed to each other, respectively. A gate insulating filmis formed between the source-drain regions () and (′) including the extension regions () and (′) and a gate electrode () is formed on the gate insulating film (). A region corresponding to a pocket region(′) in a conventional structure having a higher impurity concentration than that of a channel region is not formed in a tip portion of the extension region(′) and a peripheral portion of the extension region ().