Photoetching system capable of detecting mask curvature and detection method

Abstract

The invention provides a photoetching system capable of detecting mask curvature. A plurality of measurement marks used for measuring mask curvature are needed to be added in a mask manufacturing process; and sensors are arranged in corresponding positions of the measurement marks and used for detecting information of the measurement marks, so that the deformation quantity of the mask curvature can be calculated. The photoetching system is simple in structure, small in occupied space, and capable of ensuring movement freedom of the photoetching system. The invention also provides a detection method adopting the photoetching system capable of detecting mask curvature; the sensors obtain vertical coordinates of the measurement marks on the mask through detection and transmit the vertical coordinates to a control system to obtain a curved surface calculation formula used for describing the deformation curved surface of the mask; the control system obtains deformation quantity used for representing the mask curvature of the deformation curved surface in a scanning direction and in a non-scanning direction according to the formula; the method is simple and convenient to operate; information detection can be performed by the sensors in real time in the exposure process, and the mask curvature can be calculated, so that timeliness and accuracy of detection are ensured consequently.

Description

technical field [0001] The invention relates to the field of semiconductor photolithography, in particular to a photolithography system and a detection method capable of detecting the curvature of a mask. Background technique [0002] In photolithography systems, masks are used to create patterns that are imprinted onto a substrate. In a typical photolithographic imaging process, a positioning device is used to position the mask at the correct position, so as to ensure that the generated pattern can be correctly mapped to the corresponding process layer of the integrated circuit. The correct positioning of the mask depends on several factors, such as maintaining the correct object image distance between the mask and the integrated circuit process layer. If the vertical positioning of the mask is wrong, it will affect the distance between the mask and the integrated circuit process layer. The accuracy of the image distance between objects will lead to deterioration of imagin...

AI Technical Summary

Problems solved by technology

Because the mask is generally fixed by a suction cup, but the suction cup can only fix the edge of the mask, so the middle part of the mask will bend after being heated and expanded, and even the deformation of the edge part fixed by the suction cup will be transmitted to the middle of the mask partially released

The thermal expansion of the mask will cause the pattern on the mask to deviate from the optimal object plane position, thus causing the vertical positions of any two points on the mask to be different, resulting in a problem when using the points on the mask for vertical positioning Vertical positioning error, resulting in calculation error of object image distance

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