Analysis of AC- gm dispersions due to traps in nitride charge trap layer and generated interface traps in 3-D NAND flash memory cells

The AC-gm dispersions are measured to analyze trap profiles in a cell of 3-D NAND flash cell string before and after P/E cycling. After 4k P/E cycling, the trap density (Nt) near the interface between the poly-Si channel and the tunneling oxide is increased according to the extracted Nt profile. The temperature dependency of the AC-gm dispersion is also investigated.