Photomask of large-size spliced product and online measuring and positioning method

The invention provides a photomask of a large-size spliced product and an online measurement positioning method. The photomask of the large-size spliced product comprises at least two exposure unit areas with different functions and the same size, the four corners of each exposure unit area are respectively provided with a locking angle pattern in mirror symmetry, and the locking angle patterns are located in the chip areas of the exposure unit areas; when the photomask is adopted to carry out a splicing photoetching process on a wafer, the locking angle patterns are spliced on the wafer to form a cross mark, the cross mark divides the whole chip area of the wafer into a plurality of measuring units with the same size, and each measuring unit corresponds to one exposure unit area. According to the photomask of the large-size spliced product and the online measurement positioning method, the online measurement range can be expanded, and the process difference on the wafer level can be monitored. 本申请提供一种大尺寸拼接产品