| 摘要 |
PROBLEM TO BE SOLVED: To improve the withstand voltage reliability of a high withstand voltage lateral semiconductor device having a planar p-n junction. SOLUTION: On a surface layer of a p-type semiconductor substrate 1, n-well regions 2 are formed, p-base regions 3 are formed on a surface layer of the n-well regions 2, n<+> -source regions 4 are form on a surface layer of the p-base regions 3, n<+> -drain regions 5 are formed on a surface layer of the n-well regions 2 apart from the p-base regions 3, a LOCOS thin film 10 and a PSB thin film 11 are first surface protective films 14 are formed on the p-base regions 3 and n-well regions 2 sandwiched between the n<+> -source and n<+> -drain regions 4, 5, a resistive silicon nitride thin film 12 is formed thereon. Cx Hy or Six Cy Fz thin film are formed as a second protective film 13 on this film 12. |
