Semiconductor memory and voltage application method to semiconductor memory

Abstract

The present invention provides a semiconductor memory and a method of applying a voltage to a semiconductor memory element capable of preventing a peak electric field from being applied to a tunnel oxide film, thereby preventing a reduction in the number of times of rewriting or a reduction in data retention characteristics. The semiconductor memory of the present invention has: a storage unit (10) and a control word line selection drive circuit (205), a well drive circuit (207) and a source line selection drive circuit (206), when the floating gate in the storage unit (10) (101) a pulse generating circuit (301), a delay circuit (302), a delay circuit (303) and a delay circuit (304) outputting a pulse signal (S1) when injecting electrons. And, the control word line selection drive circuit (205) receives the delay signal (S2) from the delay circuit (302) to change the potential of the control word line, and the well drive circuit (207) receives the delay signal (S3) from the delay circuit (303). ) changes the potential of the well, and the source line selection drive circuit (206) receives the delay signal (S4) from the delay circuit (304) to change the potential of the source line.

Description

technical field [0001] The present invention relates to a semiconductor memory and a method of applying a voltage to a semiconductor memory element. Background technique [0002] In recent years, with the popularization of portable devices and the demand for energy saving and waste reduction, there has been an increasing demand for semiconductor devices incorporating nonvolatile memories that can rewrite data and retain data even when the power is turned off. As semiconductor nonvolatile memory, there are flash memory and ferroelectric memory, each of which has advantages and disadvantages, and each has its own characteristics in the field of products used. For example, flash memory, because the size of the storage unit is small is conducive to large capacity, but the number of times of rewriting is not much. On the other hand, ferroelectric memory has many times of rewriting, but since the size of the memory cell is also large, it is not conducive to increasing the capacit...

AI Technical Summary

Problems solved by technology

For example, flash memory, because the size of the storage unit is small, it is conducive to large capacity, but the number of rewriting is not much

On the other hand, ferroelectric memory can be rewritten many times, but it is not conducive to large-capacity due to the large size of the memory cell.

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