发明名称 |
Dynamic RAM, dynamic RAM plate voltage setting method, and information processing system |
摘要 |
A dynamic RAM enhanced in integration and storage capacity, a method of setting a plate voltage of the dynamic RAM, and an information processing system reduced in size and enhanced in performance are provided. The plate voltage is set such that a leakage current of an information storage capacitor when a bit line voltage is positive relative to the plate voltage is made substantially equal to a leakage current of the capacitor when the bit line voltage is negative relative to the plate voltage. For this plate voltage setting, a plate voltage generating circuit is provided with an output voltage adjusting capability. A monitoring capacitor is formed on the same semiconductor wafer on which the information storage capacitor is formed. This monitoring capacitor is formed by a same method by which the information storage capacitor is formed, and is made of a same material of which the information storage capacitor is made. The monitoring capacitor is tested in a wafer probing process. Based on a measurement result, the plate voltage is set to an optimum level. The information processing system is constituted with the dynamic RAM as its memory device having the optimum plate voltage.
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申请公布号 |
US5459684(A) |
申请公布日期 |
1995.10.17 |
申请号 |
US19940197768 |
申请日期 |
1994.02.16 |
申请人 |
HITACHI, LTD. |
发明人 |
NAKAMURA, MASAYUKI;MATSUMOTO, TETSURO;OSHIMA, KAZUYOSHI |
分类号 |
G11C11/404;G11C11/407;G11C11/4074;(IPC1-7):G11C7/00;G11C11/40 |
主分类号 |
G11C11/404 |
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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