Patent ID: 7064370

Claim:
A semiconductor device, comprising: a plurality of lower bit lines arranged in parallel in a first direction on a semiconductor substrate; a lower field oxide film formed within the lower bit lines and defining an active region and a device isolation region; a first insulating film for accumulating charges formed on the active region having a structure in which a nitride film and an oxide film are sequentially stacked on an oxide film; a plurality of word lines arranged in parallel in a second direction orthogonal to the first direction of the lower bit lines; a second insulating film for accumulating charges formed on the word lines, corresponding to the first insulating film for accumulating charges, and having a structure in which a nitride film and an oxide film are sequentially stacked on an oxide film; an upper field oxide film formed on the word lines and corresponding to the lower field oxide film; a plurality of upper bit lines arranged in parallel in the first direction on the upper field oxide film and the second insulating film for accumulating charges and corresponding to the lower bit lines; and an upper substrate formed between the plurality of the upper bit lines on the second insulating film for accumulating charges.