摘要 |
One aspect of the present invention relates to a method of making a flash memory cell, involving the steps of providing a substrate having a flash memory cell thereon; forming a self-aligned source mask over the substrate, the self aligned source mask having openings corresponding to source lines; implanting a source dopant of a first type in the substrate through the openings in the self-aligned source mask corresponding to source lines; removing the self-aligned source mask from the substrate; forming a MDD mask over the substrate, the MDD mask covering the source lines and having openings corresponding to drain lines; and implanting a medium dosage drain implant of a second type to form a drain region in the substrate adjacent the flash memory cell. |