Surface scanner with thin film gauge
July 20, 2013. 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 ReferencesMethod and device for controlling the film thickness of evaporated film Light collector for optical contaminant and flaw detector Method and apparatus for light span microscopic dark-field display of objects Semiconductor wafer surface inspection apparatus and method Apparatus for detecting faults on the surface of a resist master disc and measuring the thickness of the resist coating layer Surface inspection method and apparatus therefor Particle detection on a patterned or bare wafer surface Method and apparatus for inspecting surface conditions Particle detector for rough surfaces Patent #: 5189481 InventorsAssigneeApplicationNo. 095144 filed on 07/20/1993US Classes:356/237.5, On patterned or topographical surface (e.g., wafer, mask, circuit board)356/632Of light permeable materialExaminersPrimary: Rosenberger, Richard A.Attorney, Agent or FirmForeign Patent References
International ClassG01N 021/88AbstractAn optical surface scanner for semiconductor wafers and like substrates having one channel with a detector receiving collected scattered light and another channel with a detector receiving reflected light. The scattered light signal is indicative of surface haze, particle count and size, while the reflected light signals are indicative of film thickness and/or surface properties as in the case of an opaque or absorbing layer. The latter signal may be used to correct the particle count and size determination and may also be used simultaneously for thin film measurement. The reflectivity or thin film measurement signals may be used to characterize a film layer controller to improve the accuracy of the deposited thickness of the layer. | |
