Shimadzu Corporation

Ebara Corporation

Kazunari Shinya

Yoichi Kobayashi

Shunsuke Nakai

Yasuo Tsukuda

Hitoshi Tsuji

Junki Ishimoto

Takashi Nishimura

Shunsuke; c/o Ebara Corporation Nakai

Yoichi; c/o Ebara Corporation Kobayashi

Hitoshi; c/o Ebara Corporation Tsuji

A polishing state monitoring apparatus measures characteristic values of a surface, being polished, of a workpiece to determine the timing of a polishing end point. The polishing state monitoring apparatus includes a light-emitting unit for applying light from a light source to a surface of a workpiece being polished, a light-receiving unit for receiving reflected light from the surface of the workpiece, a spectroscope unit for dividing the reflected light received by the light-receiving unit into a plurality of light rays having respective wavelengths, and light-receiving elements for accumulating the detected light rays as electrical information. The polishing state monitoring apparatus further includes a spectral data generator for reading the electrical information accumulated by the light-receiving elements and generating spectral data of the reflected light, and a processor for calculating a predetermined characteristic value on the surface of the workpiece based on the spectral data generated by the spectral data generator.

Polishing state monitoring method

Polishing state monitoring apparatus and polishing apparatus

Polishing state monitoring apparatus and polishing apparatus and method

The present invention provides a method of measuring the thickness of a thin film or thin layer by a spectroscopic measurement, which is applicable to the measurement of a multiple layered film whose layers have different refractive indices. According to the method, an interference light from the film is measured to create a measured spectrum. The waveform of the measured spectrum can be approximately represented by a linear sum of base spectrums. Accordingly, various constructed spectrums are created using base spectrums each having a cycle interval as a parameter. Then, the constructed spectrum that minimizes the square error against the measured spectrum is identified. The least square error is calculated for each of predetermined cycle intervals. A graph is drawn to represent the relation between the least square error and the cycle interval. The correspondence between the layers and the plural minimum points of the least square error appearing on the graph is determined. The thickness of each layer is calculated from the cycle interval at which the minimum point appears and the refractive index of the layer.

Method of and apparatus for measuring thickness of thin film or thin layer

A monochromatic light is cast on a thin layer, and the intensity of the reflected light which is an interference light of the lights reflected by the front surface and back surface of the layer. A spectrum (a measured spectrum) is obtained from the measured intensity by scanning the wavenumber of the monochromatic light. On the other hand, a constructed spectrum is created based on an assumed thickness using a predetermined function. Then an error between the measured spectrum and the constructed spectrum is calculated. The value of the error is plotted against the assumed thickness, and the point at which the error is minimum is detected. The assumed thickness at the error-minimum point is determined as the thickness of the layer.

Thickness measurement method and apparatus

A method and apparatus for determining a base line of a measurement curve wherein after preparing a template having an arc upward convex, a CPU of the data processing system moves, without rotating, the template with the arc of the template always contacting the measurement curve and determines the base line as the envelope of the arc of the template. During moving of the template, the system may move the template horizontally under the measurement curve; calculate, at every horizontal point at a given horizontal position of the template, the vertical distance between the arc of the template and the arc of the measurement curve; detect the minimum of the vertical distance at the given horizontal position of the template; and move the template vertically at the given horizontal position by the minimum vertical distance. To determine the base line, the CPU initializes data of the base line by the smallest value and judges whether the arc of the template after moved is superior to the arc before moved at every point of the arc after moved. The data of the base line is updated at the points where the arc after moved is superior to the are before moved by the data of the arc after moved.

Method and apparatus for determining a base line of a measurement

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Osaka, Japan

Kazunari Shinya