Fabrication method of nonvolatile semiconductor memory device

Details Fabrication method of nonvolatile semiconductor memory device Fabrication method of nonvolatile semiconductor memory device

1994-11-01

1996-02-20

Thomas, Tom

Fishing, trapping, and vermin destroying

437 52, H01L 218247

Patent

active

054928460

ABSTRACT:
A fabrication method of a split-gate type flash EEPROM with an improved data-storage characteristic. Insulator strips extending along a first direction are formed on a semiconductor substrate at intervals. The strips are in contact with active regions and a field insulator film. After a first gate insulator film is formed on uncovered parts of the active regions, respectively, a first patterned conductor film is formed to cover the insulator strips and the first gate insulator film. The first conductor film is anisotropically etched to produce floating gate electrodes lower in height than the stripes on the first gate insulator film without using a mask. Each of the floating gate electrodes has an oblique side face. A second gate insulator film is formed to cover the floating gate electrodes and exposed parts of the active regions. A second conductor film is formed to cover the second gate insulator film and the insulator strips. The second conductor film is etched back to flatten a surface of the second conductor film until tops of the strips are exposed. The second conductor film is patterned to produce control gate electrodes. After the insulator strips are removed, drain regions and source regions are formed in the active regions respectively.

REFERENCES:
patent: 5021848 (1991-06-01), Chiu
patent: 5073513 (1991-12-01), Lee
Raul-Adrian Cernea et al., "A 1Mb Flash EEPROM", 1989 IEEE International Solid-State Circuits Conf., Digest of Technical Papers, Feb. 16, 1989, pp. 138-139 and 316.

Affiliated with

Also associated with

Rating

Fabrication method of nonvolatile semiconductor memory device does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Fabrication method of nonvolatile semiconductor memory device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fabrication method of nonvolatile semiconductor memory device will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1355683