TFT CHARGE STORAGE MEMORY CELL HAVING HIGH-MOBILITY CORRUGATED CHANNEL AND METHOD OF MANUFACTURING THE SAME

摘要

A rewriteable nonvolatile memory cell having two. bits. per cell is described. The memory cell preferably operates by storing charge in a dielectric charge storage layer or in electrically isolated conductive na®ocrystals by a channel hot electron injection method. In preferred embodiments the channel region has a corrugated shape, providing- additional isolation between the two storage regions. The channel region is deposited and is preferably formed of polycrystalline germanium or silicon-germanium. The memory cell of the present invention can be formed in memory arrays; in preferred embodiments,, multiple memory levels are formed stacked above a single substrate. The memory cell comprises a transistor (50) having source (52) and drain (54) connected to bit lines (30). The channel region is formed over a dielectric structure (32) and is covered by a charge storage dielectric (36) and a wordline (44).