| 摘要 |
PURPOSE: To surely and quickly detect the etching terminating point of a semiconductor wafer etching system, by scanning the surface of a semiconductor wafer with a narrow converged radiant energy beam, and analyzing a reflected beam by parking the radiant energy beam on a parking spot decided from the reflected beam. CONSTITUTION: A wafer 10 is scanned with a laser beam spot 10 along a route 20 in a chip position. The width (w) of a spot 18 is made remarkably smaller than the width W of an opening, such as the scribed line S of a photoresist layer 36. The parking spot P in a flat area 38 on the wafer 10 is decided from the reflected part of the beam at the scanning time. Then, the beam is parked on the spot P and the reflected part of the beam is analyzed by keeping the beam on the spot P during the remaining time of an etching process. As a result of the analysis, the time when a silicon dioxide 34 is completely etched off is decided from the appearance of the flat section of the intensity curve of the reflected beam. Therefore, the etching terminating point can be detected surely and quickly.
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