Lighting uniformity correction device, lighting uniformity correction method and exposure projection system

Abstract

The invention relates to a lighting uniformity correction device, a lighting uniformity correction method and an exposure projection system. The lighting uniformity correction device comprises a variable light shielding correction device, a variable gray compensation plate device and a variable reflection mirror array device, wherein the variable light shielding correction device comprises a plurality of correction component pairs which are arranged on the cross section of a lighting beam; the plurality of the correction component pairs are arranged at intervals in a non-scanning direction tocover a whole lighting field and are overlapped in the scanning direction to cover the whole lighting field; the variable gray compensation plate device comprises two flat plates which can be moved relatively and have different gray transmittance rates; and the variable reflection mirror array device comprises a variable reflection mirror optical device; and the variable reflection mirror opticaldevice consists of a plurality of reflection mirror arrays with variable reflection rates. By adjusting the shapes and the overlapping modes of the component pairs, the transmittance rates of the flatplates and the reflection rates of the reflection mirror arrays, the lighting uniformity of the whole lighting field in multiple lighting modes is adjusted. By adopting the lighting uniformity correction device, the problems that gray compensation plates are frequently replaced, and properties of pupil uniformity and view field integral uniformity cannot be met in multiple lighting modes are solved.

Description

technical field [0001] The invention relates to the technical field of lithography illumination, in particular to an illumination uniformity correction device, a correction method and an exposure projection system. Background technique [0002] Photolithography is used in the manufacture of semiconductor devices. Photolithography uses electromagnetic radiation, such as ultraviolet (UV), deep UV, or visible light, to produce fine patterns in the design of semiconductor devices. Many types of semiconductor devices, such as diodes, transistors, and integrated circuits , can be fabricated by photolithography. A lithography exposure system usually includes an illumination system, a reticle containing a circuit pattern, a projection system, and a silicon wafer and a silicon wafer alignment stage for coating photoresist. The illumination system illuminates the circuit pattern on the reticle, and the projection system takes the An image of the illuminated area of ​​the circuit diag...

AI Technical Summary

Problems solved by technology

[0008] The third solution is: in the early stage of the lighting system, a fixed gray scale compensation plate is used to eliminate the non-uniformity caused by the compensation structure of the variable shading head. However, with the increasing demand for lighting modes of the lithography lighting system, The fixed gray scale compensation plate cannot satisfy the uniformity optimization in the case of multiple lighting modes

[0009] At present, in the high NA front lighting system, there are dozens or even hundreds of lighting modes. It is difficult to make such a variable gray scale compensation plate compatible with the process, and the long-term problems caused by the uniformity of the lighting system and the objective lens system Drift and uniformity changes caused by pollution during use require a redesign of the variable gray scale compensation board every six months. Replacing the compensation board once will also affect the yield. It is necessary to propose a solution to the uniformity compensation and uniformity of multiple lighting modes. Solution for frequent replacement of variable gray scale compensation board caused by drift

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