Nonvolatile semiconductor memory device

0.1 I I0 I00 I 000
[hour]
COMPARATIVE ELEMENT A
OA writing characteristics
X El erasing characteristics

0.1 1 I0 I00 I000 [hour]

FIG. 7 COMPARATIVE ELEMENT B E: 4 '-—' 3 CA writing characteristics 5 2 XIII erasing characteristics 1 0 1 2 3 4 0.1 1 10 100 1000 [hour] FIG. 8 COMPARATIVE ELEMENT C r; 4 ‘-5’ 3 CA writing characteristics > 2 X 1:1 erasing characteristics 1 0 -1 -Z -3 -4 0.1 1 10 100 1000

[hour]

FIG. 12

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112

21

FIG 13
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