A lithography lighting system

Abstract

The invention provides a lithography illumination system which comprises a high-pressure mercury lamp, a coupled lens group, a quartz rod, a relay lens group and a mask plate, wherein light emitted from the mercury lamp is converged through the coupled lens group and forms uniform illuminating light in the quartz rod through repeated total reflection, and the illuminating light is amplified through the relay lens group and forms an illuminating view field with a certain numerical aperture, size and uniformity on the mask plate. The lithography illumination system is characterized in that the relay lens group is used for improving the illumination intensity of the edge field in the illuminating view field. Compared with the prior art, the lithography illumination system has the advantages that the illumination intensity of the edge field in the illuminating view field is improved, and the influence caused by the numerical aperture change of the mercury lamp is avoided, so that the mercury lamp light source and the whole illumination system have high practicality.

Description

technical field [0001] The invention relates to the field of integrated circuit equipment manufacturing, in particular to a lithography lighting system for a lithography device. Background technique [0002] Photolithography, also known as microlithography, is used to manufacture semiconductor devices and is an important process in semiconductor manufacturing. Many semiconductor devices can be fabricated by photolithography, such as diodes, transistors, and integrated circuits. In the existing photolithography method, an optical system illuminated by a high-pressure mercury lamp is often used, mainly exposing the three lines of g (436nm) h (405nm) i (365nm), and accurately transferring the pattern on the mask to the substrate (such as: silicon wafer). )superior. [0003] According to the requirements of lithographic fabrication and exposure of semiconductor devices, the lighting system required by the lithography machine is usually required to be designed by telecentricity...

AI Technical Summary

Problems solved by technology

If the deviation between the design telecentric value and the actual value is too large, the unevenness on the mask surface due to processing will be extremely sensitive, which will cause a great change in the imaging quality on the silicon wafer surface, especially the distortion

[0005] In the existing design, due to the limitation of coating conditions, the influence of the chamfering of the integrating rod, the edge and the diffuse reflection of the rough edge, etc., the transmittance at the edge of the coated glass lens will be lower than that at the middle position, making the incident on the mask surface The light intensity is high in the middle and low in the surrounding areas, such as figure 1 As shown, thus affecting the uniformity of the light intensity distribution on the mask surface

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