NAND based NMOS NOR flash memory cell, a NAND based NMOS nor flash memory array, and a method of forming a NAND based NMOS NOR flash memory array

摘要

A NOR flash nonvolatile memory device provides the memory cell size and a low current program process of a NAND flash nonvolatile memory device and the fast, asynchronous random access of a NOR flash nonvolatile memory device. The NOR flash nonvolatile memory device has an array of NOR flash nonvolatile memory circuits. Each NOR flash nonvolatile memory circuit includes a plurality of charge retaining transistors serially connected in a NAND string. A drain of a topmost charge retaining transistor is connected to a bit line associated with the serially connected charge retaining transistors and a source of a bottommost charge retaining transistor is connected to a source line associated with the charge retaining transistors. Each control gate of the charge retaining transistors on each row is commonly connected to a word line. The charge retaining transistors are programmed and erased with a Fowler-Nordheim tunneling process.