Random access memory.

摘要

A random access memory comprises a semiconductor body (2l) of one conductivity type, at least one first well region (23A) of an opposite conductivity type formed in the surface area of the semiconductor body (2l), and a memory cell array (MCA) having a plurality of memory cells formed in the first well region (23A). A peripheral circuit (PC-l, PC-2) for driving the memory cell array (MCA) is formed in at least one second well region (23B, 23C) of the opposite conductivity type formed separately from the first well region (23A) in the surface area of the semiconductor body (2l). The second well region (23B, 23C) is set at a bias level deeper than the first well region (23A).