| 摘要 |
PURPOSE:To detect surely a foreign matter such as dust, etc., adhered on the glass face side of a reticle by a method wherein a laser beam is irradiated to the fine pattern provided on an IC, scattered light from the edge part of the pattern is detected to perform the comparative inspection, while reflected light from the pattern is also detected to perform the comparative inspection the same. CONSTITUTION:The transcribed image 121 of the circuit pattern and the transcribed image 122 of the foreign matter on the glass face side of the reticle adjoining thereto are provided on a semiconductor chip 120, and the transcribed image 124 of the circuit pattern is formed also on another chip 123. An wafer 125 having the two chips like this on the surface is fixed with an wafer chuck 126, and objective lenses 128, 127 and beam splitters 136, 135 are arranged respectively at the upper parts of the chip 123 and the transcribed image 122 of the foreign matter. A reflected laser beam 140 from the transcribed image 122 of the foreign matter and a reflected beam 141 from the chip 123 having no transcribed image of the foreign matter are detected respectively by photomultipliers 137, 138 by this way, outputs amplified by amplifiers 131, 132 are inputted to a differential amplifier 133, and existence of the foreign matter is detected based upon the difference of the quantity of light. |
