Method of forming memory device
AssigneePowerchip Semiconductor Manufacturing Corporation
InventorsWen Chung Yang, Shih Hsi Chen, Wei-Chang Lin
Life of this patent
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Abstract
Provided is a memory device including a substrate, a plurality of word-line structures, a plurality of cap structures, and a plurality of air gaps. The word-line structures are disposed on the substrate. The cap structures are respectively disposed on the word-line structures. A material of the cap structures includes a nitride. The nitride has a nitrogen concentration decreasing along a direction near to a corresponding word-line structure toward far away from the corresponding word-line structure. The air gaps are respectively disposed between the word-line structures. The air gaps are in direct contact with the word-line structures. A method of forming a memory device is also provided.
Claims11
A method of forming a memory device, comprising:
- (a) forming a word-line structure on a substrate;
- (b) conformally forming a nitride layer on the word-line structure;
- (c) forming a sacrificial pattern on the nitride layer to expose an upper portion of the nitride layer;
- (d) performing a nitridation treatment to nitride the upper portion of the nitride layer into a first cap layer;
- (e) removing the sacrificial pattern to expose a lower portion of the nitride layer;
- (f) performing an etching process to thin the lower portion of the nitride layer;
- (g) performing an oxidation process to oxidize a thinned lower portion of the nitride layer to an oxide layer;
- and
- (h) removing the oxide layer to expose a lower portion of the word-line structure, while the first cap layer covers an upper portion of the word-line structure.
Dependencies are inferred from the claim text.