| 摘要 |
PURPOSE:To inspect a defective multi-layer pattern in a single operation, by processing selectively a photo-electric converted signal obtained by irradiating a multi-layer structured specimen by a pattern photo-electric converted signal obtained by irradiating a plurality of standard patterns. CONSTITUTION:A laser ray from a laser source 4 is reflected by half-mirrors 6, 7 and reflecting mirror 8 through a deflecting system 5 and irradiates masters 13, 14 and specimen 15. The specimen 15 is composed of, for example, lower layer pattern 15a and upper layer pattern 15b and the masters 13, 14 are provided with patterns 13a, 14a corresponding to the patterns 15a, 15b. The laser ray after penetrating the masters 13, 14, is taken out as master outputs M1, M2 and the laser ray irradiating the specimen as specimen output T1. The outputs M1, M2 are processed via a selecting circuit and the output T1 is given to a plurality of switching circuits and processed by a signal processing circuit of different window widths and a defect of the specimen of the multi-layer pattern structure can be detected at a single action of inspection. |
