Patent ID: 8633080

Claim:
A method of making a semiconductor device, comprising: forming an isolation region surrounding an active region, wherein the active region is in a substrate; depositing a first charge storage layer on a top surface of the active region and over the isolation region; depositing a first layer comprising one of a group consisting of metal and polysilicon on the active region; etching the first layer to leave a first line and a second line of the first layer across the active region and the isolation region; after etching the first layer, depositing a second charge storage layer over the active region and the isolation region; depositing a second layer comprising one of a group consisting of metal and polysilicon over the second charge storage layer; removing portions of the second layer and the second charge storage layer to leave a third line between the first line and the second line and separated from the first line and the second line by a remaining portion of the second charge storage layer; forming a drain on a first side of the first line, wherein the first side of the first line is away from the third line; forming a source on a first side of the second line, wherein the first side of the second line is away from the third line; and doping the first line, the second line, and the third line over the isolation region to a first conductivity type and doping the first line, the second line, and the third line over the active region to a second conductivity type.