发明名称 |
Method and apparatus to image metallic patches embedded in a non-metal surface |
摘要 |
Small metallic patches embedded in a mainly non-metallic surface may be detected and mapped by placing a wire coil at the free end of a cantilever, with a fine tip made of a ferro-magnetic material located at its center. An alternating current is passed through the coil so that when it is near a metallic patch eddy currents are induced in the patch. These produce a small magnetic moment in the patch which pulls the tip towards the surface. This movement of the tip is detected by observing a light beam that is reflected off the surface of the cantilever. By plotting the output of a photodetector, sensistive to small changes in the reflected beam's position, as a function of the tip's location over the surface, a map of the metallic patches is produced.
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申请公布号 |
US6064201(A) |
申请公布日期 |
2000.05.16 |
申请号 |
US19980114125 |
申请日期 |
1998.07.13 |
申请人 |
CHARTERED SEMICONDUCTOR MANUFACTURING LTD.;NATIONAL UNIVERSITY OF SINGAPORE |
发明人 |
CHA, CHER LIANG RANDALL;GONG, HAO;CHOR, ENG FONG;CHAN, LAP |
分类号 |
G01R33/038;(IPC1-7):G01N27/90;G01R33/00;G01R33/12;G01R31/00;G01V3/00 |
主分类号 |
G01R33/038 |
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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