| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus for testing abnormal focus in reduction projection exposure without having to reduce the throughput, even if foreign matters attach to a semiconductor wafer. SOLUTION: An abnormal focus testing apparatus 3 judges whether a focus value in a shot area is normal or abnormal, before a reduction projection aligner 100 carries out reduction projection exposure. When|reference value Z0-focus value Z1 in a shot area to be exposed|>1.0μm, the abnormal focus testing apparatus 3 determines that the focus is abnormal. The reference value Z0 is an average value of focus values from a shot area located in the outermost periphery of the semiconductor wafer 100 to a shot area one shot inside the shot area in the outermost periphery of the wafer. |
