摘要 |
Multi-level nonvolatile memory devices using variable resistive elements, the multi-level nonvolatile memory devices including a word line, a bit line, and a multi-level memory cell coupled between the word line and the bit line, the multi-level memory cell having first resistance level and a second resistance level higher than the first resistance level when the first and second write biases having the same polarity are applied thereto, and a third resistance level and a fourth resistance level ranging between the first and second resistance levels, when third and fourth write biases having different polarities from each other are applied thereto.
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