SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device having high latch-up resistance; and provide a manufacturing method of the semiconductor device.SOLUTION: A semiconductor device comprises: a first conductivity type semiconductor substrate; a first conductivity type first well formed in a first region of the semiconductor substrate; a second conductivity type first transistor formed in the first well; a second conductivity type second well which is formed in an annular second region surrounding the first region and which touches a lateral face of the first well; a second conductivity type deep well layer formed on a bottom face of the first well and a bottom face of the second well in a contacting manner; a second conductivity type third well formed in a third region adjacent to the second region; and a first conductivity type second transistor formed in the third well. An impurity concentration in the second well is higher than an impurity concentration in the third well.