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公开(公告)号:WO1996019711A1
公开(公告)日:1996-06-27
申请号:PCT/US1995004556
申请日:1995-04-13
Applicant: TENCOR INSTRUMENTS
Inventor: TENCOR INSTRUMENTS , NIKOONAHAD, Mehrdad , RIGG, Philip, R. , WELLS, Keith, B. , CALHOUN, David, S.
IPC: G01B11/00
CPC classification number: G01N21/9501 , G01N21/94 , G01N21/956
Abstract: A surface height detection and positioning device for use in a surface inspection system. A light beam (25) impinges obliquely upon the surface (22), and a position detector (38) with a mechanical window (45) defining an aperture (46) receives specularly reflected light (33) producing a plurality of electrical signals. The aperture's width (46), along a scan direction, is of sufficient size to create a train of signals from each of the plurality of signals, having a frequency equal to the scan frequency. These signals carry information responsive to the position of the reflected beam (33) impinging on the detector and the beam's intensity. To abrogate information responsive to intensity variations at the detector, an electronic circuit (100) determines the sum and the difference of the plurality of signals, producing a summed signal and a difference signal, respectively. The difference signal is divided by the summed signal, thereby producing a normalized signal which represents the height of the surface.
Abstract translation: 一种用于表面检测系统的表面高度检测和定位装置。 光束(25)倾斜地撞击在表面(22)上,并且具有限定孔径(46)的机械窗口(45)的位置检测器(38)接收产生多个电信号的镜面反射光(33)。 沿着扫描方向的孔径宽度(46)具有足够的尺寸以产生具有等于扫描频率的频率的来自多个信号中的每一个的信号序列。 这些信号响应于入射在检测器上的反射光束(33)的位置和光束的强度而携带信息。 为了消除响应于检测器处的强度变化的信息,电子电路(100)分别确定多个信号的和和差,产生加和信号和差分信号。 差分信号除以相加信号,从而产生表示表面高度的归一化信号。
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公开(公告)号:EP0804713A1
公开(公告)日:1997-11-05
申请号:EP95916365.0
申请日:1995-04-13
Applicant: Tencor Instruments
Inventor: NIKOONAHAD, Mehrdad , RIGG, Philip, R. , WELLS, Keith, B. , CALHOUN, David, S.
CPC classification number: G01N21/9501 , G01N21/94 , G01N21/956
Abstract: A surface height detection and positioning device for use in a surface inspection system. A light beam (25) impinges obliquely upon the surface (22), and a position detector (38) with a mechanical window (45) defining an aperture (46) receives specularly reflected light (33) producing a plurality of electrical signals. The aperture's width (46), along a scan direction, is of sufficient size to create a train of signals from each of the plurality of signals, having a frequency equal to the scan frequency. These signals carry information responsive to the position of the reflected beam (33) impinging on the detector and the beam's intensity. To abrogate information responsive to intensity variations at the detector, an electronic circuit (100) determines the sum and the difference of the plurality of signals, producing a summed signal and a difference signal, respectively. The difference signal is divided by the summed signal, thereby producing a normalized signal which represents the height of the surface.
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