SEMICONDUCTOR STORAGE DEVICE

To improve the electrical characteristics of a memory cell transistor in a semiconductor storage device.SOLUTION: The semiconductor storage device includes: a semiconductor, a first insulator, a second insulator, a first conductor, a fourth insulator and a fifth insulator. The first insulator adjoins to the semiconductor and the second insulator adjoins the first insulator. The third insulator is provided on the first conductor. The fourth insulator is provided between the second insulator and the first conductor. The fifth insulator is provided between the second insulator and the third insulator and has an oxygen concentration different from an oxygen concentration of the fourth insulator.SELECTED DRAWING: Figure 5 【課題】半導体記憶装置におけるメモリセルトランジスタの電気特性を改善する。【解決手段】実施形態の半導体記憶装置は、半導体と、第１絶縁体と、第２絶縁体と、第１導電体と、第４絶縁体と、第５絶縁体とを含む。第１絶縁体は半導体に隣接し、第２絶縁体は第１絶縁体に隣接する。第３絶縁体は、第１導電体の上に設けられる。第４絶縁体は、第２絶縁体と第１導電体との間に設けられる。第５絶縁体は、第２絶縁体と第３絶縁体との間に設けられ、第４絶縁体の酸素濃度と異なる酸素濃度を有する。【選択図】図５