Method of manufacturing semiconductur device

Abstract

Disclosed is a method of manufacturing a semiconductor device. The method includes forming an oxide-nitride-oxide (ONO) layer over a semiconductor substrate, and forming a recess over the semiconductor substrate by etching the ONO layer, forming a vertical structure pattern being higher than the ONO layer over the recess, sequentially forming a spacer oxide film and a first gate poly over the side wall of the vertical structure pattern, and forming a nitride film spacer at a partial region of the side wall of the first gate poly, removing the nitride film spacer, and forming a second gate poly in a spacer shape over the side wall of the first gate poly, and forming a first split gate and a second split gate, symmetrically divided from each other, by removing the vertical structure pattern. The invention can prevent the characteristic between the memory units based on the registration photoetching precision change in photolithography.

Description

[0001] This application claims priority from Korean Patent Application No. 10-2008-0058229 filed on Jun. 20, 2008, which is hereby incorporated by reference in its entirety. technical field [0002] The invention relates to a manufacturing method of a semiconductor device, in particular to a split gate type semiconductor memory device. Background technique [0003] Nonvolatile semiconductor memory devices are capable of electrically erasing and storing data, and retain data even when power is not supplied to the memory device, and thus are increasingly used in various fields including mobile communication systems and memory cards. [0004] Among these nonvolatile memory devices, a flash memory device is a memory device capable of executing a program for each cell and capable of erasing data for each block or sector. [0005] Since the flash memory device uses a conductive material such as doped polysilicon as a floating gate material, parasitic capacitance between adjacent g...

AI Technical Summary

Problems solved by technology

[0012] When there is a difference between the length L1 of the first separation nitride film 120-1 and the length L2 of the second separation nitride film 120-2, the length of the separation charge trap nitride film of a memory cell such as a flash memory cell may vary. Uniformity, and the uniformity of the memory cell characteristics will decrease, therefore, the reliability of the semiconductor device will be reduced

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