| 摘要 |
Disclosed is a template and a method for using the template for focus control of pattern definition image in lithographic process, particularly for IC production. The template has at least a serrated vernier and at least a rhombus printed thereon. In use, the template is mounted on a mask used for pattern definition during a lithographic process. Upon development of a wafer image of the mask, in the normal course of lithography, there is also visible on the wafer an image of the template. This image, particularly the rhombus pattern, can be easily visually inspected by quality control personnel. The rhombus pattern shows a defocus condition because its normally straight and parallel sides and corners show a roundness even with the slightest defocus. Wafers that have not been properly imaged during lithography can be discarded without wasting further process steps in IC production to enhance yield.
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