Alignment method and micro-device manufacturing method used for shadow cast scan photo-etching machine

Abstract

The invention discloses an alignment method of phase grating detection by using three basic grating periods applied in a scanning projection lithography tool and a micro-device manufacturing way by using the method. The alignment method of the invention applied in the scanning projection lithography tool uses three periods phase grating in a substrate marker or a substrate station reference marker, uses a first order diffraction light of the three periods as an alignment signal, simultaneously realizes a big capture range and gets high alignment precision and strong signal intensity, improves system signal to noise ratio, simplifies optical design and debugging difficulty, simplifies hardware realization, reduces signal processing cost and improves alignment efficiency.

Description

Technical field [0001] The present invention relates to lithography machine technology, and in particular to alignment technology of scanning projection lithography machines. Background technique [0002] Applying a step-scan projection lithography machine to complete the pattern transfer task of micro-machining basically involves basic steps such as workpiece loading, aligning the workpiece area to be processed with the mask, workpiece exposure, and workpiece unloading, especially the workpiece requirements. In the case of multi-layer processing, the precise alignment of the workpiece to be processed area and the mask is the prerequisite to ensure that the workpiece is processed correctly as the line width continues to shrink. When the graphics is accurately projected to the workpiece to be processed area or a new layer When the accurate registration of graphics is projected onto the previously formed area of ​​the workpiece to be processed, appropriate exposure of the curr...

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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