The origin of oxide degradation during time interval between program/erase cycles in NAND Flash memory devices
Yung-Yueh Chiu, Hung-Te-En Tsai, Kai‐Chieh Chang, kumari Roshni, Hsin-Chiao Li, Toshiaki Takeshita, Masaru Yano, R. Shirota · Japanese Journal of Applied Physics · 2021
Abstract This paper investigates the origin of NAND cell degradation during the time interval ( t wait ) between program/erase (P/E) cycles. It is observed that, at room temperature, the transconductance reduction Δ G m , max is sensitive to t wait from erase-to-program, and longer t wait from erase-to-program results in larger Δ G m , max . In contrast, Δ G m , max has almost no clear dependence on t wait from program-to-erase. Using our previous statistical Δ G m , max method, the activation energy ( E A , G ) of oxide damage creation is extracted. As the starting voltage ( V CG , 0 ) of incremental step pulse programming (ISPP) varied from 14.6 to 17.6 V, E A , G has a shift of about 11 meV and 13 meV for both t wait from erase-to-program of 0.1 s and 4 s, respectively. We also found that E A , G