发明名称 |
An improved photodetector and device employing the photodetector for converting an optical signal into an electrical signal |
摘要 |
<p>An anti-reflective coating having a composite layer of silicon nitride and silicon dioxide may be formed over the entire photosensitive region of the photodetector to minimize the amount of reflection. The composite layer comprises a silicon nitride layer and a dielectric layer contiguous to the silicon nitride layer. The anti-reflective coating may be formed in a CMOS process for fabricating the PNjunction in the photodiode and CMOS devices for amplifying the photodetector signal, where the polysilicon gate layer is used as a etch stop. The P+ or N+ material in the PN junction of the photodiode has a distributed design where two portions of the region are separated by a distance in the range of Xd to 2Xd, where Xd is the one-sided junction depletion width, to enhance the electric field and to reduce the distance traveled by the carriers for enhancing bandwidth. A heavily doped region of the opposite type may be added between the two portions to further enhance the electric field. A mask is used to shield a portion of the substrate in which the photodetector region has been or is to be formed when other portions of the substrate region are implanted with a dopant to adjust at least one of the threshold voltages of the other portions. The mask prevents the photodetector region from being affected by such implant. <IMAGE></p> |
申请公布号 |
EP0987767(A2) |
申请公布日期 |
2000.03.22 |
申请号 |
EP19990307140 |
申请日期 |
1999.09.09 |
申请人 |
CAPELLA MICROSYSTEMS, INC. |
发明人 |
TSANG, KOON WING |
分类号 |
H01L31/10;G02B1/11;H01L31/0216;(IPC1-7):H01L31/021;H01L27/144;H01L31/18;H01L31/103 |
主分类号 |
H01L31/10 |
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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