High-power excimer laser homogenization using dual-microlens arrays.

Area of Science:

• Optics and Photonics
• Laser Technology
• Semiconductor Manufacturing

Background:

• High-power excimer lasers are crucial for advanced lithography processes.
• Achieving uniform illumination is essential for high-resolution patterning in lithography.

Purpose of the Study:

• To research and develop an effective excimer laser homogenization method for lithography.
• To propose a tunable excimer laser model for practical light sources.
• To design a high-power excimer laser homogenizer with improved beam uniformity.

Main Methods:

• Utilized microlens arrays for excimer laser homogenization.
• Developed a tunable excimer laser model based on multi-Gaussian Schell-model partially coherent light.
• Employed matrix optics and scalar diffraction theory for homogenizer design.
• Analyzed the impact of laser stability parameters on uniformity.

Main Results:

• Achieved a square beam with a low non-uniformity of 1.28% using the designed homogenizer.
• The proposed tunable excimer laser model accurately reflects practical light source conditions.
• Experimental verification confirmed the model's accuracy and the homogenizer's reliability.

Conclusions:

• The developed microlens array-based excimer laser homogenization effectively meets lithography requirements.
• The tunable laser model and homogenizer design offer a reliable solution for uniform high-power excimer laser illumination.
• The study validates the importance of laser stability for maintaining beam uniformity in lithography systems.