NONVOLATILE STORAGE DEVICE AND CONTROL METHOD OF THE SAME

• Main Authors: TANAKA TOSHIJI, TAKAGI TAKESHI, YAMATO MASAKI, OIDE HIROYUKI, YAMAGUCHI TAKESHI
• Format: Patent
• Language: English; Japanese
• Published: 08.02.2016
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INFORMATION STORAGE; PHYSICS; SEMICONDUCTOR DEVICES; STATIC STORES

PROBLEM TO BE SOLVED: To provide a nonvolatile storage device enabling appropriate control, and further to provide a control method thereof.SOLUTION: A nonvolatile storage device includes: a memory cell being interposed between a pair of pieces of wiring and including a variable resistive element; and a control circuit applying a voltage between the pair of pieces of wiring interposing the memory cell. The control circuit repeatedly performs a first voltage application step S201 of applying a first writing voltage between the pair of pieces of wiring interposing the memory cell and a first verification step S202 of applying a first voltage less than the first writing voltage and comparing a cell current flowing through the memory cell with a first threshold current until a magnitude relation between the cell current and the first threshold current satisfies first conditions. Further, the control circuit performs a second voltage application step S203 of applying a second writing voltage between the pair of pieces of wiring interposing the memory cell when the first conditions are satisfied.SELECTED DRAWING: Figure 22 【課題】好適な制御を可能にする不揮発性記憶装置及びその制御方法を提供する。【解決手段】不揮発性記憶装置は、一対の配線の間に挟まれた可変抵抗素子を含むメモリセルと、このメモリセルを挟む一対の配線間に電圧を印加する制御回路とを有する。制御回路は、メモリセルを挟む一対の配線間に第１の書き込み電圧を印加する第１の電圧印加ステップＳ２０１と、第１の書き込み電圧よりも小さい第１の電圧を印加して、メモリセルに流れるセル電流を第１の閾値電流と比較する第１のベリファイステップＳ２０２とを、セル電流と第１の閾値電流との大小関係が第１の条件を充足するまで繰り返し行う。また、制御回路は、第１の条件が充足された場合に、メモリセルを挟む一対の配線間に第２の書き込み電圧を印加する第２の電圧印加ステップＳ２０３を行う。【選択図】図２２