Marker for photo-etching machine aligning and aligning using the same

Abstract

The present invention discloses an alignment mark and an alignment signal treatment method used for projection scanning lithography machine based on four-cycle phase grating. The method makes use of a marked coarse grating branch signal for the determination of capture range and position of the coarse alignment, and makes use a marked fine grating branch signal for the determination of the fine alignment position, thereby ensuring the obtainment of high-precision alignment position by only adopting diffraction optical signal of plus or minus 1 grade, improving the alignment efficiency and simplifying the alignment optical system.

Description

technical field [0001] The invention relates to lithography machine technology, in particular to the alignment technology of scanning projection lithography machine. Background technique [0002] Applying a step-and-scan projection lithography machine to complete the pattern transfer task of micromachining basically involves basic steps such as workpiece loading, alignment of the workpiece area to be processed with the mask, workpiece exposure, and workpiece unloading. In the case of multi-layer processing technology, the precise alignment of the workpiece area to be processed and the mask plate is the premise to ensure that the workpiece is correctly processed when the line width is continuously reduced. When the graphics are accurately projected to the workpiece area to be processed or a new When the accurate registration of the layer graphics is projected on the area of ​​the previously formed workpiece to be processed, the proper exposure of the current layer can realize...

AI Technical Summary

Problems solved by technology

The advantage of this scheme is that it can achieve automatic capture and high alignment accuracy, but the disadvantage is that it requires a special wedge adjustment device and complicated adjustment. In addition, the high-order signals in the diffracted light are weak, while this method is Higher alignment accuracy is achieved by relying on high-order signals. In practice, as the power of the reflected signal (especially the high-order signal) of the mark (especially the silicon wafer mark) is too low, the high-order signal cannot actually be used. Therefore, it cannot reliably provide the highest alignment accuracy

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