| 摘要 |
PURPOSE:To improve a measuring throughput, with a reduction in a relative movement between an object and a detecting means, by detecting a height position of a local part of the surface of the object simultaneously by a plurality of detection means. CONSTITUTION:A wafer W to be inspected is placed on a moving stage 1 and a height position of a local part of the surface of the wafer W is detected with an optical type detecting means. The detection means is constituted of pairs of detection means comprising projection system lenses 20d-24d for projecting a measuring beam askew to a local part of the surface of the wafer W and a light receiving systems 20g-24g for receiving reflected light from said local part. Said pairs of detection means and the wafer are moved relatively parallel with a moving stage. Photoelectric signals obtained from the detection means are inputted into a measuring means, with which condition such as flatness of the wafer surface is analyzed. |
