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自由电子激光光源（Free Electron Laser，FEL）可发出波长为13.5nm的极紫外（Extreme Ultra-violet,EUV）辐射，在EUV光刻领域能够发挥重要作用。但FEL自身的高相干特性以及类高斯光强轮廓分布特征，会对成像带来不利影响，无法满足EUV光刻领域成像应用需求。本文通过计算模拟的方法，设计了一种匹配FEL应用的、用于EUV波段去相干和光强均匀化的新型匀光管结构。模拟结构显示，针对波长为13.5nm、直径200μm、发散度20mrad的FEL-EUV高斯光束，采用新型匀光管结构，与常规匀光管结构相比，在同等长度和内径时，具有更显著的去相干能力和光场均匀化作用。当新型匀光管内径为1mm、总长度不低于0.6m、倾斜角度为10mrad时，高相干光场完全被扰乱，实现低相干光输出。并可获得均匀照明光场，光强分布不均匀性数值从常规圆柱型匀光管的28.38降低至0.97。同时，相应能量传输效率为37.6%，最大传输效率达到44.58%。结果表明，新型匀光管结构能够满足EUV激光去相干应用需求，同时可提高照明视场光强分布均匀性，在EUV光刻领域及其他成像应用具有很大应用前景。Free Electron Laser (FEL) is a high-quality laser source with wavelengths ranging from short-wave X-rays to long-wave infrared ray. Extreme Ultra-violet (EUV) radiation at λ=13.5nm emitted by FEL can be used in integrated circuit manufacturing, such as EUV lithography exposure, mask defect inspection.However, the high spatial coherence characteristics and similar Gauss intensity profile distribution of FEL source has a negative effect on imaging, and cannot meet the requirements of imaging applications in EUV lithography. In this work, a newly light pipe for decoherence and intensity uniformity at EUV spectral range is designed through the simulation calculations. New light pipe consists of a two pairs of tilted elements are symmetrically distributed in the y-z plane and x-z plane, respectively.In this way, the beam transmission divergence in two dimensions can be widened at the same time, and the disturbance of the ray transmission track and spatial phase distribution is increased, so as to achieve the uniformization of light intensity and the reduction of spatial coherence. The simulation results show,for an EUV gaussian beam at the λ=13.5nm, with diameter of 200μm and a divergence of 20mrad, compared with the conventional light pipe structure, the newly designed light pipe has more significant decoherence and illumination field uniformity. When the inner diameter is 1mm, the total length is not less than 600mm, and the tilt angle is 10mrad of the newly light pipe, the basically uniform illumination field can be obtained, the coherence is completely disordered,and non-uniformity of light intensity distribution at the illumination field is reduced to 0.97 from 28.38 achieved by conventional cylindrical light pipe.At the same time, the light power transmission efficiency is about 37.6% and the maximum transmission efficiency is about 44.58%. With the increase of the number of reflections, the uniformity can be further improved. When the inner diameter and tilted angle of the light pipe are unchanged, the length of the light pipe is increased to 1m, the non-uniformity of intensity distribution at the illumination field is further reduced to 0.90, and the light power transmission efficiency is about 22.35%. The results show that the newly designed light pipe structure can meet the application requirements of decoherence and improving the uniformity of illumination field at EUV wavelength range, and it has great application prospects in EUV lithography and other imaging applications.
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Keywords:
- extreme ultraviolet source /
- free electron laser /
- light pipe /
- phase /
- intensity uniformity
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[1] Zhao Z T,Dai Z M,Zhang W Z,Liu B,Deng H X,Zhang M Z,Tian S Q 2023 J.Fudan Univ.62 293(in Chinese)[赵振堂,戴志敏,张文志,刘波,邓海啸,张满洲,田顺强2023复旦学报62 293] {中文期刊}
[2] Yang J Y,Dong W R,Jiang L,Yuan K J,Wang F J,Wu G R,Qiao D Z,Zhang W Q,Yang X M 2023 Sci.Sin.Chim.53 2103(in Chinese)[杨家岳,董文锐,江凌,袁开军,王方军,吴国荣,乔德志,张未卿,杨学明中国科学:化学53 2103] {中文期刊}
[3] Wu J C,Cai M,Lu Z J,Huang N S,Feng C,Zhao Z T 2023 Acta Opt.Sin.43 2114002-1(in Chinese)[吴嘉程,蔡萌,陆宇杰,黄楠顺,冯超,赵振堂2023光学学报43 2114002-1] {中文期刊}
[4] Zhang S J,Guo Z,Cheng J M,Wang Y,Chen J H,Liu Z 2023 Acta Phys.Sin.72 105203-1(in Chinese)[张少军,郭智,成加皿,王勇,陈家华,刘志2023物理学报72 105203-1] {中文期刊}
[5] Lin Z X,Wei X H,Liao T F,Wang W Y,Du J,Yang M L 2022 Acta Photonica Sin.51 1014008-1(in Chinese)[林宏翔,魏晓慧,廖天发,王文辕,杜鹃,杨明亮2022光子学报51 1014008-1] {中文期刊}
[6] Norio N,Ryukou K,Hiroshi S,Kimichika T,Yasunori T,Yosuke H,Tsukasa M,Miho S,Takanori T,Olga A T,Takashi O,Hiroshi K 2023 Jap.J.Appl.Phys.62 SG0809-1{英文期刊}
[7] Ma X Z,Zhang F,Huang H J 2021 Chin.J.Lasers.48 2005001-1(in Chinese)[马晓喆,张方,黄惠杰2021中国激光48 2005001-1] {中文期刊}
[8] Liu J H,Zhang F,Huang H J 2022 Laser&Optoelectronics Prog.59 0922011-1(in Chinese)[刘佳红,张方,黄惠杰2022激光与光电子学进展59 0922011-1] {中文期刊}
[9] Kenneth A G,Markus P B,Antoine W,Iacopo M,Senajith B R,Arnaud P A,Michael R D,Carl W C,Chao W L,Daniel J Z,James B M,Patrick P N,Anne R 2014 SPIE 9048 90480Y-1{英文期刊}
[10] Han-Kwang N,Rilpho L D,Gosse C D V 2020 US Patent 20 200 152 345
[11] Christopher N A,Ryan H M,Patrick P N 2011 SPIE 7969 796938-1{英文期刊}
[12] Yuan T Y,Shao S K,Sun X P,Li H Q,Hua L,Sun T X 2023 Acta Phys.Sin.72 034203-1(in Chinese)[袁天语,邵尚坤,孙学鹏,李惠泉,华陆,孙天希2023物理学报72 034203-1] {中文期刊}
[13] 班尼恩V,巴特瑞P,范格尔库姆R,阿门特L,彼得D,德维里斯G,栋克尔R,恩格尔伦W,弗里基恩斯O,格瑞米克L,卡塔伦尼克A,鲁普斯特拉E,尼恩惠斯H K,尼基帕罗夫A,瑞肯斯M,詹森F,克鲁兹卡B 2019 CN Patent 110 083 019
[14] Xiao Y F,Zhu J,Yang B X,Hu Z H,Zeng A J,Huang H J 2013 Chin.J.Lasers.40 0216001-1(in Chinese)[肖艳芬,朱菁,杨宝喜,胡中华,曾爱军,黄惠杰2013中国激光40 0216001-1] {中文期刊}
[15] Li H,Ma Y Y,Yin H Y,Han X Q,Huang Y F,Wu X B 2024 Laser&Optoelectronics Prog.61(in Chinese)[李慧,马钺洋,尹皓玉,韩晓泉,黄宇峰,吴晓斌2024激光与光电子进展61] {中文期刊}
[16] Akram M N,Tong Z M,Ouyang G M, Chen X Y, Kartashov V 2010 Appl.Opt. 49 3297{英文期刊}
[17] Li D Y, Kelly D P,Sheridan J T 2013 Appl.Opt. 52 8617{英文期刊}
[18] Hsiao Y N, Wu H P, Chen C H, Lin Y C, Lee M K, Liu S H 2014 Opt.Rev.21 715{英文期刊}
[19] Sun M J,Lu Z K 2010 Opt.Eng.49 024202-1{英文期刊}
[20] Li L,Han X Q,Zhao S W,Bao H Y,Wang X B 2014 Laser&Optoelectronics Prog. 51 011401-1(in Chinese)[李丽,韩学勤,赵士伟,包鸿音,王兴宾2014激光与光电子学进展51 011401-1{中文期刊}
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