The Effect of Field Oxide Recess on Cell $V_{\rm TH}$ Distribution of nand Flash Cell Arrays

Autor: Sung-Hoi Hur, Chang-Sub Lee, Keon-Soo Kim, Min-Cheol Park, Won-Seong Lee
Rok vydání: 2008
Předmět:
Zdroj: IEEE Electron Device Letters. 29:1050-1052
ISSN: 0741-3106
Popis: We present our study on the effect of field oxide recess on cell-programming-speed uniformity of nand flash cell memory. Due to the short distance between the control gate and the shallow-trench-isolation (STI) edge, the control-gate voltage generates uniform distribution of an electric field on the STI edge and provides strong immunity to fabrication process variation in cell programming. Therefore, the optimized field oxide recess offers an inherently narrower cell V TH distribution, fastening multilevel-cell programming speed while minimizing the floating-gate interference. Experimental results on 63-nm cell arrays show that the cell V TH distribution is reduced by 18% or more as field oxide recess increases.
Databáze: OpenAIRE