Method for fabricating nonvolatile memory device
View Patent ↗A nonvolatile memory device and method for fabricating the same are provided. The nonvolatile memory device includes an active region; a source region formed in the active region; a source line formed on the source region and electrically connected with the source region, to cross over the active region; word lines aligned at each sidewall of the source line to cross over the active region in parallel with the source line; and a charge storage layer interposed between the word lines and the active region. Since the word lines are formed at both sides of the source line using an anisotropic etch-back process, without photolithography, the area of a unit cell can be reduced.
1. A method for fabricating a nonvolatile memory device, comprising:
forming a source region in an active region of a semiconductor substrate;
forming an insulating film having an opening that partially exposes the source region;
forming a conductive film on the insulating film, the conductive film being electrically connected with the source region through the opening;
patterning the conductive film to form a source line connected with the source region and crossing the active region;
forming spacers at sidewalls of the source line and on the insulating film;
removing a portion of the insulating film, while leaving another portion of the insulating film remaining below the spacers;
conformally forming a charge storage layer on the active region, the spacers, and the source line;
forming word lines on the charge storage layer on the active region, the word lines being formed to have a spacer-like configuration that is self-aligned with respect to the sidewalls of the spacers; and
forming a drain region in the active region adjacent the word lines and spaced apart from the source region.
2. The method of claim 1 , wherein
the source line having a width less than the source region.
3. The method of claim 1 , wherein the source region has a width greater than the source line.
4. The method of claim 3 , wherein the spacers are formed over a portion of the source region corresponding to the greater width.
5. The method of claim 1 , wherein the spacers and the word lines are symmetrically formed at both sides of the source line.