Semiconductor wafer processing with across-wafer critical dimension monitoring using optical endpoint detection
May 16, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesProcess and device for monitoring the plasma etching of thin layer utilizing pressure changes in the plasma Optical emission spectroscopy end point detection in plasma etching Process monitor and method thereof Resist development method Process for determining photoresist develop time by optical transmission Method and apparatus for endpoint detection in a semiconductor wafer etching system Endpoint detection system and method for plasma etching Method of detecting an end point of surface treatment Patent #: 4998021 InventorAssigneeApplicationNo. 243558 filed on 05/16/1994US Classes:430/30, INCLUDING CONTROL FEATURE RESPONSIVE TO A TEST OR MEASUREMENT356/436, Of fluent material356/442, With light detector356/443, Of photographic film356/632, Of light permeable material430/311Making electrical deviceExaminersPrimary: McCamish, Marion E.Assistant: Duda, Kathleen Attorney, Agent or FirmForeign Patent References
International ClassG03F 007/26AbstractA method for across-wafer critical dimension uniformity performance monitoring in the manufacture of semiconductor devices employs a number of optical endpoint detectors at sites at the wafer face which are spaced across the wafer face. Each optical endpoint detector is able to directly measure the end point of the process step at its site. One of these optical endpoint detectors is used to control the process, and when the endpoint has been reached for this site the process completion time is predicted and this completion time is used to control the processing equipment. For example, if the process step being monitored is the development of photoresist, then the developing operation is ended based upon this calculated completion time derived from the detected endpoint for the control site. The other sites are used to monitor across-wafer performance. The output of each of these other optical detectors is used to determine the endpoint for each monitor site, and these endpoints are compared with the control endpoint to determine across-wafer critical dimension performance and conformance to specification. The wafers can thus be flagged if out-of-limit, and need not be processed through subsequent steps.Other References
Field of SearchINCLUDING CONTROL FEATURE RESPONSIVE TO A TEST OR MEASUREMENTMaking electrical device Post image treatment to produce elevated pattern Measuring or testing (e.g., of operating parameters, property of article, etc.) Measuring or testing (e.g., of operating parameters, end point determination, etc.) Measuring, analyzing or testing Fluent material in optical path Of fluent material With light detector Of photographic film |
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