发明名称 |
Method for programming a single EPROM or flash memory cell to store multiple levels of data that utilizes a forward-biased source-to-substrate junction |
摘要 |
Multiple logic levels can be programmed into a single EPROM or FLASH memory cell by applying one of a corresponding number of programming voltages to the control gate of a memory cell that has a forward-biased source-to-substrate junction and a reverse-biased drain-to-substrate junction. During programming, the bias conditions form substrate hot electrons which, in addition to the channel hot electrons, accumulate on the floating gate. By utilizing the substrate hot electrons, a much lower control gate voltage can be utilized during programming. More importantly, however, once the channel hot electrons cease to exist, the substrate hot electrons and holes converge to a stable charge that is related to the control gate voltage used during programming and the programmed threshold voltage of the cell.
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申请公布号 |
US5511021(A) |
申请公布日期 |
1996.04.23 |
申请号 |
US19950394171 |
申请日期 |
1995.02.22 |
申请人 |
NATIONAL SEMICONDUCTOR CORPORATION |
发明人 |
BERGEMONT, ALBERT;CHI, MIN-HWA |
分类号 |
G11C11/56;G11C16/10;(IPC1-7):G11C11/40 |
主分类号 |
G11C11/56 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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