PURPOSE: To prevent the generation of junction leakage due to the counter diffusion of impurities and a defective contact by forming a high melting-point metallic silicide wiring using a titanium silicide and setting impurity concentration in an N-type impurity diffusion layer at a value lower than impurity concentration in a P-type impurity diffusion layer.

CONSTITUTION: Source-drain regions 29, 30 in a P channel transistor and an N channel transistor are connected by the wiring 36 of titanium silicide, and impurity concentration in the source-drain region 30 in the N channel transistor is set at a value lower than impurity concentration in the source drain region 29 in the P channel transistor. According to such a device, the diffusion of a P-type impurity through the wiring is prevented. Consequently, even when an N-type impurity such as As, P, etc., in the source-drain region 30 in the N channel transistor is diffused into the P+ source-drain region 29 in the P channel transistor through the titanium silicide wiring 36, the P type of the region 29 is not inverted into an N type, and junction leakage and a defective contact are not caused.