NONVOLATILE SEMICONDUCTOR MEMORY

摘要

PROBLEM TO BE SOLVED: To enable an improvement in the characteristics of a high voltage-resistant MIS transistor and a reduction in the area of a circuit including the high voltage-resistant MIS transistor. SOLUTION: A nonvolatile semiconductor memory of the present invention comprises: a monocrystalline semiconductor substrate 21 having a first epitaxial layer 22 on the surface thereof; and a plurality of memory cells MC and high voltage-resistant transistors HVTr arranged on the monocrystalline semiconductor substrate 21. The impurity concentration of the monocrystalline semiconductor substrate 21 is lower than that of the first epitaxial layer 22. COPYRIGHT: (C)2008,JPO&INPIT