Patent ID: 7643338

Claim:
A program method for programming of a flash memory device, the method comprising: applying a program bias to a selected memory cell of a plurality of memory cells within a memory cell string, the memory cell string comprising a source select line, a plurality of memory cells and a drain select line, wherein the plurality of memory cells are arranged in series between the source select line at one end and the drain select line at an opposite end; applying a first pass bias to two memory cells next to the selected memory cell in a source select line direction relative to the selected memory cell, wherein the first pass bias is lower than the program bias; applying a second pass bias to all memory cells in a drain select line direction relative to the selected memory cell, wherein the first pass bias is lower than the second pass bias; and applying a third pas bias to remaining memory cells in the source select line direction relative to the selected memory cell to which the program bias is applied excluding the two memory cells to which the first pass bias is applied, the third pass bias creating channels in the memory cells in the drain select line direction relative to the selected memory cell to which the program bias is applied, wherein the third pass bias is lower than the second pass bias.