摘要 |
A method of forming a memory device with improved isolation between diffusion lines. Parallel, spaced apart thick oxide strips (201) are grown on a substrate. Next, spaced apart, parallel strips (302) having a polysilicon (302a) and nitride (302b) layer, oriented perpendicular to the first strips (201), are formed. The oxide (201 ) between the second strips is removed, followed by an implantation to form source (402) and drain (401) regions. The nitride layer (302B) on the second strips is removed on those strips between two drain diffusions (401) and an oxidation is performed to form self-aligned thick oxide (602) over the source and drain regions. The strips from which the nitride has been removed are also oxidized, thus providing isolation between adjacent drain lines.
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