| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device of low manufacturing cost, which can load a high breakdown voltage MOS transistor having resistance against negative potential and a semiconductor element of another type in a mixed manner; and provide a manufacturing method of the semiconductor device.SOLUTION: A semiconductor device comprises NDMOSs including: a first n-type well ND1 and a second n-type well ND2, which are formed in a first depth from a surface of a p-type semiconductor substrate, and in a second depth deeper than the first depth, respectively; p-type back gate regions PBG1 and PBG2; n-type source regions S1 and S2; n-type drain regions D1 and D2; and field insulation films STIs each formed between the p-type back gate region and the n-type drain region. In the first n-type well, a first transistor NDMOS1 having low withstanding reverse voltage is formed, and in the second n-type well, a second transistor NDMOS2 having low withstanding reverse voltage is formed. |
