| 摘要 |
Methods of operating non-volatile memory cells (e.g., EEPROM devices) include the use of negative substrate biases during programming and erasing operations. Theses methods include the step of erasing the memory cell by withdrawing negative charge from a floating gate therein using a positive control electrode bias and a negative substrate bias. The use of a negative substrate bias increases the potential difference between the control electrode and the floating gate and this increase results in faster and more reliable erasing. A step is also performed to program the memory cell by accumulating negative charge on the floating gate using a positive control electrode bias, a negative substrate bias and a positive drain bias. Here, the negative substrate bias is used advantageously to reduce the likelihood that non-selected memory cells will become inadvertently programmed during operations to program selected memory cells.
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