Height measurement method

Abstract

Abstract PURPOSE:To rapidly measure a height with high accuracy by performing the scanning of laser beam in an X-axis direction and calculating the position of an inflection point on a scanning line from the quantity of reflected beam and subsequently performing the scanning in a Y-axis direction to calculate the position of an apex to measure a height. CONSTITUTION:The quantity of reflected beam and a height signal are detected while a Y-stage 5 is moved around the apex of an object 3 to be measured at a constant speed by a control means 9. The center position 17 between a position 15 where the quantity 10 of reflected beam exceeds a judge level TH and a position 16 where said quantity 10 is short of said level TH is judged at an inflection point by a judge means 12 and set to the Y-coordinates of an apex position 2. Next, the stage 5 is moved so that an initial position comes to the Y-coordinates of the position 2 by the means 9, and the quantity of reflected beam and the height signal are detected while an X-stage 6 is moved. The center position 19 is judged from the quantity 10 of reflected beam in the same way. Since this position 19 is the apex position of the object 3, the height signal of this position becomes that of the apex position. Therefore, scanning is respectively once performed in the X- and Y-axis directions to make it possible to rapidly measure a height with high accuracy.

Inventors

• 👤 Yutaka Hashimoto
• 👤 豊 橋本
• 👤 Keiji Imai
• 👤 啓二 今井
• 👤 Hiroaki Ijichi
• 👤 伊地知　弘明

Bibliographic Details