Optics: measuring and testing – By configuration comparison – With photosensitive film or plate
Patent
1997-02-12
1999-02-16
Kim, Robert
Optics: measuring and testing
By configuration comparison
With photosensitive film or plate
451 6, 25055927, G01B 1106, B24B 4912
Patent
active
058726330
ABSTRACT:
The present invention provides methods and apparatus which permit the in-process, in-situ, substantially real time measurement of the actual thickness of a surface layer of a work piece, e.g., a semiconductor wafer. A probe is disposed proximate to the outer perimeter of a polishing pad on a CMP table such that the probe establishes optical contact with the wafer surface as a portion of the wafer extends beyond the outer perimeter of the polishing pad. A nozzle may be provided to apply a stream of compressed air at the disk surface under inspection to thereby remove excess slurry from the local region of the workpiece being inspected. A broad band light source is employed in conjunction with a fiber optic cable to direct light at the wafer surface. A bifurcated probe is employed such that the light applied to the workpiece surface is reflected back to and captured by a corresponding optical sensor connected to a fiber optic cable. The captured reflected light received by the receptor sensor and fiber optic cable assembly is applied to a photospectrum meter which analyzes the reflected light. An output signal from the photospectrum meter is transmitted to a processor which includes a smart algorithm configured to calculate the thickness of the surface layer. Alternatively, the reflective characteristics of the semiconductor layers may affect the nature of the reflected signal; changes in the reflected signal can be detected to indicate when a metallic layer has been removed from an oxide layer.
REFERENCES:
patent: Re34425 (1993-11-01), Schultz
patent: 4462860 (1984-07-01), Szmanda
patent: 4805348 (1989-02-01), Arai et al.
patent: 5099614 (1992-03-01), Arai et al.
patent: 5240552 (1993-08-01), Yu et al.
patent: 5329732 (1994-07-01), Karlsrud et al.
patent: 5486129 (1996-01-01), Sandhu et al.
patent: 5486701 (1996-01-01), Norton et al.
patent: 5498196 (1996-03-01), Karlsrud et al.
patent: 5498199 (1996-03-01), Karlsrud et al.
patent: 5543919 (1996-08-01), Munoki
patent: 5555472 (1996-09-01), Clapis et al.
patent: 5555474 (1996-09-01), Ledger
patent: 5559428 (1996-09-01), Li et al.
patent: 5562529 (1996-10-01), Kishii et al.
patent: 5568252 (1996-10-01), Kusada et al.
patent: 5609511 (1997-03-01), Moriyama et al.
Patent Abstracts Of Japan, vol. 097, No. 010, Oct. 31, 1997 & JP 09 159409 (Dainippon Screen Mfg. Co., Ltd.), Jun. 20, 1997 --see abstract.
Holzapfel Paul
Karlsrud Chris
Lin Warren
Schlueter James
Kim Robert
Merlino Amanda
Speedfam Corporation
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