发明名称 |
Programming of LDD-ROM cells. |
摘要 |
<p>ROM memories made in MOS or CMOS technology with LDD cells may be programmed advantageously in a relatively advanced stage of fabrication by decoupling an already formed drain region from the channel region of cells to be permanently made nonconductive (programmed) by implanting a dopant in an amount sufficient to invert the type of conductivity in a portion of the drain region adjacent to the channel region. In CMOS processes, the programming mask may be a purposely modified mask commonly used for implanting source/drain regions of transistors of a certain type of conductivity. By using high-energy implantation and a dedicated mask, the programming may be effected at even later stages of the fabrication process. <IMAGE></p> |
申请公布号 |
EP0575688(A2) |
申请公布日期 |
1993.12.29 |
申请号 |
EP19920830552 |
申请日期 |
1992.10.01 |
申请人 |
SGS-THOMSON MICROELECTRONICS S.R.L. |
发明人 |
GHIO, EMILIO GIAMBATTISTA;MERONI, GIUSEPPE;RE, DANILO;BALDI, LIVIO |
分类号 |
G11C17/12;H01L21/8238;H01L21/8246;H01L27/092;H01L27/112;(IPC1-7):H01L27/112;H01L21/82 |
主分类号 |
G11C17/12 |
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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