Trap Profiling in Nitride Storage Layer in 3-D NAND Flash Memory Using Retention Characteristics and AC- $\text{g}_{\mathrm {m}}$ Method
Min-Kyu Jeong, Ho-Jung Kang, Sung-Min Joe, Sung-Kye Park, Byung‐Gook Park, Jong‐Ho Lee · IEEE Electron Device Letters · 2015
The trap density (Nt) in nitride storage layer of 3-D NAND flash memory cells with tube-type channel structure is extracted. To extract Ntprofile in the nitride layer, retention characteristics, and ac-transconductance (gm) method are used, and equations are derived in cylindrical coordinate. The Ntprofile at E - ETsmaller than 1 eV is extracted using retention characteristics of the cells measured at high temperature. The peak value of extracted Ntis ~1 × 1019 cm-3eV-1at a EC- ETof 0.93 eV. AC-gmmethod is used to profile the Ntin E - EThigher than 1 eV. Extracted Ntprofile shows a reasonable continuity between both approaches and looks like a Gaussian function.