先进光刻中的聚焦控制预算(I)-光路部分

钟志坚; 李琛毅; 李世光; 郭磊; 韦亚一

doi:10.37188/CO.2021-0033

先进光刻中的聚焦控制预算(I)-光路部分

doi: 10.37188/CO.2021-0033

钟志坚^{1, 2,},
李琛毅^{1, 2},
李世光^{1, 2, 3, ,},
郭磊^{1, 2, 3},
韦亚一^{1, 2}

1.
中国科学院微电子研究所，北京 100029
2.
中国科学院大学，北京 100049
3.
江苏影速集成电路装备股份有限公司，无锡 214142

基金项目: 国家自然科学基金资助项目(No. 61804174；No. 61604172)

详细信息

作者简介:
钟志坚（1996—），男，江西赣州人，硕士研究生，2018年于武汉理工大学获得学士学位，主要从事光刻对焦控制与检测方面的研究。E-mail：zhongzhijian18@mails.ucas.ac.cn

李世光（1973—），女，辽宁沈阳人，研究员，硕士生导师。1993年和1996年于哈尔滨工业大学分别获得学士、硕士学位，2005年于清华大学获得博士学位，2005-2011年分别于新加坡南洋理工大学和美国北卡罗来纳大学做博士后，主要从事光刻技术和光学测量的研究。E-mail：lishiguang@tsinghua.org.cn

中图分类号: TP394.1；TH691.9
计量
- 文章访问数: 3822
- HTML全文浏览量: 2258
- PDF下载量: 477
- 被引次数: 0
出版历程
- 收稿日期: 2021-02-01
- 修回日期: 2021-03-08
- 网络出版日期: 2021-04-30
- 刊出日期: 2021-09-18

Budget analysis of focus control in advanced lithography (I) -optical path

ZHONG Zhi-jian^{1, 2
,},
LI Chen-yi^{1, 2},
LI Shi-guang^{1, 2, 3
, ,},
GUO Lei^{1, 2, 3},
WEI Ya-yi^{1, 2}

1.
Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China
2.
University of Chinese Academy of Sciences, Beijing 100049, China
3.
Jiangsu Yingsu Integrated Circuit Equipment Co., Ltd, Wuxi 214142, China

Funds: Supported by National Natural Science Foundation of China (No. 61804174; No. 61604172)

More Information

Corresponding author: lishiguang@tsinghua.org.cn

摘要

摘要: 随着大规模集成电路芯片制造的技术节点不断缩小，光刻机的聚焦控制变得尤为困难。为了保证硅片曝光的质量，需要快速、准确地将硅片在几十纳米的聚焦深度范围（DOF）内进行快速调整。因此，需要仔细分析光刻过程中导致焦点偏移或工艺窗口变化的各种因素，制定合理的聚焦控制预算，将各种误差因素控制在一定范围内。本文聚焦极紫外（EUV）光刻，综述包含EUV在内的先进光刻机中光路部分对聚焦控制有影响的各种因素，总结它们产生的原理及仿真、实验结果，为开展先进光刻聚焦控制预算研究提供参考。
- 聚焦控制 /
- 光刻 /
- 预算 /
- 最佳焦点 /
- 聚焦深度 /
- 工艺窗口
Abstract: As the technology node of large-scale integrated circuits continues to shrink, the focus control of the lithographic tools becomes particularly difficult. In order to ensure the exposure quality of wafers, it is necessary to quickly and accurately adjust the wafer in the Depth of Focus (DOF) to a degree as small as few dozen of nanometers. For this reason, people need to carefully analyze the various factors that cause defocusing or process window changes in the lithographic process, make a reasonable focus control budget, and control the various error factors within a certain range. This paper focuses on Extreme Ultraviolet (EUV) lithography, reviews the factors that affect focus control in the optical path of an advanced EUV lithographic tool and summarizes their principles, simulation and experimental results. It can provide a reference when conducting advanced lithography focus control budget research.
- focus control /
- lithography /
- budget /
- best focus /
- depth of focus /
- process window

HTML全文

图 1 EUV光刻机中的光路示意图^[11]

Figure 1. Schematic diagram of optical system of EUV lithography machine^[11]

下载: 全尺寸图片幻灯片

图 2 NXE:3100在不同光照条件下（常规，环形，双极）获得的光刻胶图案的电子显微照片^[14]

Figure 2. Electron micrographs of photoresist patterns obtained by NXE:3100 under conventional, circular, dipole illuminations^[14]

下载: 全尺寸图片幻灯片

图 3 EUV入射光锥与出射光锥的重叠与不重叠状态

Figure 3. The overlapping and non-overlapping states of the exiting light cone and the incident light cone in EUV

下载: 全尺寸图片幻灯片

图 4 EUV掩模结构

Figure 4. Structure of EUV mask

下载: 全尺寸图片幻灯片

图 5 在双极TE照明下的一维图形(光栅)成像

Figure 5. One-dimensional graphic (grating) imaging under dipole TE illumination

下载: 全尺寸图片幻灯片

图 6 Kirchhoff和三维模型下的掩模最佳焦点的偏移情况^[26]

Figure 6. Best focus shift of the mask with Kirchhoff and the 3D model^[26]

下载: 全尺寸图片幻灯片

图 7 焦点偏移与pitch间的关系^[27]

Figure 7. Relationship between focus shift and pitch^[27]

下载: 全尺寸图片幻灯片

图 8 0级和1级的衍射相位随图形周期的变化情况^[28]

Figure 8. Results of diffraction phase of the 0th and 1st order varying with pitch^[28]

下载: 全尺寸图片幻灯片

图 9 64 nm、96 nm周期线条下的最佳焦点（点）和聚焦深度（柱）^[34]

Figure 9. Best focus(point) and DOF(bar) of different pitches (64 nm, 96 nm)^[34]

下载: 全尺寸图片幻灯片

图 10 掩模弯曲对聚焦偏移的影响^[37]

Figure 10. Effect of mask bending on focus shift^[37]

下载: 全尺寸图片幻灯片

图 11 EUV光刻机中的掩模聚焦偏移

Figure 11. Mask defocus of EUV lithography machine

下载: 全尺寸图片幻灯片

图 12 泽尼克多项式^[41]

Figure 12. Zernike polynomials^[41]

下载: 全尺寸图片幻灯片

图 13 像散与场曲对UDOF的影响^[42]

Figure 13. Effects of astigmatism and field curvature on UDOF^[42]

下载: 全尺寸图片幻灯片

图 14 曝光导致的透镜热效应

Figure 14. Lens heating caused by exposure

下载: 全尺寸图片幻灯片

图 15 (a)波前校正前的(b)波前校正后公共聚焦深度^[44]

Figure 15. Common UDOFs (a) without and (b) with appling wavefront^[44]

下载: 全尺寸图片幻灯片

图 16 杂散光对聚焦深度的影响^[50]

Figure 16. Effect of flare on depth of focus^[50]

下载: 全尺寸图片幻灯片

图 17 光刻胶三维效应导致最佳焦点偏移

Figure 17. Best focus shift caused by resist 3D effect

下载: 全尺寸图片幻灯片

图 18 亮掩模和暗掩模上不同图形的最佳焦点^[56]

Figure 18. Best focus through pitch on bright and dark mask^[56]

下载: 全尺寸图片幻灯片

参考文献(58)

[1]	China Taiwan Semiconductor Manufacturing Company. TSMC’S 5 nm (FinFET) technology[EB/OL]. [2021-04-17] https://www.tsmc.com/english/dedicatedFoundry/technology/logic/l_5nm.
[2]	DAN HUTCHESON G. Moore’s law, lithography, and how optics drive the semiconductor industry[J]. Proceedings of SPIE, 2018, 10583: 1058303.
[3]	郭杰, 李世光, 赵焱, 等. 电子束硅片图形检测系统中的纳米级对焦控制技术[J]. 中国光学,2019,12(2):242-255. doi: 10.3788/co.20191202.0242 GUO J, LI SH G, ZHAO Y, et al. Nano-scale focus control technology in electron beam wafer pattern inspection system[J]. Chinese Optics, 2019, 12(2): 242-255. (in Chinese) doi: 10.3788/co.20191202.0242
[4]	孙裕文, 李世光, 叶甜春, 等. 纳米光刻中调焦调平测量系统的工艺相关性[J]. 光学学报,2016,36(8):0812001. doi: 10.3788/AOS201636.0812001 SUN Y W, LI SH G, YE T CH, et al. Process dependency of focusing and leveling measurement system in nanoscale lithography[J]. Acta Optica Sinica, 2016, 36(8): 0812001. (in Chinese) doi: 10.3788/AOS201636.0812001
[5]	SHUMWAY J, NEAL N, MEYERS S, et al. Reduction and control of intrafield focus variation on 7nm technology[J]. Proceedings of SPIE, 2018, 10147: 101470B.
[6]	JANG J H, PARK T, PARK K D, et al. Focus control budget analysis for critical layers of flash devices[J]. Proceedings of SPIE, 2014, 9050: 90502F.
[7]	段晨, 宗明成, 范伟, 等. 浸没式光刻机对焦控制技术研究[J]. 光学学报,2018,38(9):0912002. doi: 10.3788/AOS201838.0912002 DUAN CH, ZONG M CH, FAN W, et al. Focus control technology in immersion lithography[J]. Acta Optica Sinica, 2018, 38(9): 0912002. (in Chinese) doi: 10.3788/AOS201838.0912002
[8]	姚长呈, 巩岩. 深紫外光刻投影物镜温度特性研究[J]. 中国激光,2016,43(5):0516001. doi: 10.3788/CJL201643.0516001 YAO CH CH, GONG Y. Research on temperature distribution of deep ultraviolet lithographic projection objective[J]. Chinese Journal of Lasers, 2016, 43(5): 0516001. (in Chinese) doi: 10.3788/CJL201643.0516001
[9]	VAN HAREN R, STEINERT S, MOURAILLE O, et al. The mask contribution as part of the intra-field on-product overlay performance[J]. Proceedings of SPIE, 2018, 11518: 1151813.
[10]	MASTENBROEK M. EUV industrialization high volume manufacturing with NXE3400B[J]. Proceedings of SPIE, 2018, 10809: 1080904.
[11]	WAGNER C, HARNED N. Lithography gets extreme[J]. Nature Photonics, 2010, 4(1): 24-26. doi: 10.1038/nphoton.2009.251
[12]	甘雨, 张方, 朱思羽, 等. 光刻机照明系统光瞳特性参数的评估算法[J]. 中国激光,2019,46(3):0304007. doi: 10.3788/CJL201946.0304007 GAN Y, ZHANG F, ZHU S Y, et al. Evaluation algorithm of pupil characteristic parameters in lithography illumination system[J]. Chinese Journal of Lasers, 2019, 46(3): 0304007. (in Chinese) doi: 10.3788/CJL201946.0304007
[13]	LOWISCH M, KUERZ P, CONRADI Q, et al.. Optics for ASML’s NXE: 3300B platform[C]. Proceedings of SPIE, 2013, 8679: 86791H.
[14]	HENDRICKX E, GRONHEID R, HERMANS J, et al. Readiness of EUV lithography for insertion into manufacturing: the IMEC EUV program[J]. Journal of Photopolymer Science and Technology, 2013, 26(5): 587-593. doi: 10.2494/photopolymer.26.587
[15]	LEE S H, ZHANG ZH Y. Process window study with various illuminations for EUV lithography applications[J]. Proceedings of SPIE, 2007, 6517: 65172P. doi: 10.1117/12.713447
[16]	MACK C, CHICHESTER W. Fundamental Principles of Optical Lithography: the Science of Microfabrication[M]. Chichester: Wiley, 2008: 60.
[17]	ZHAI A P, CAO Y P, CHEN B, et al. A novel method of partial coherence measuring for the illumination system and its defocus performance analysis[J]. Optik, 2013, 124(23): 6313-6317. doi: 10.1016/j.ijleo.2013.06.009
[18]	DE SIMONE D, KLJUCAR L, DAS P, et al. 28 nm pitch single exposure patterning readiness by metal oxide resist on 0.33 NA EUV lithography[J]. Proceedings of SPIE, 2021, 11609: 116090Q.
[19]	KNEER B, MIGURA S, KAISER W, et al. EUV lithography optics for sub-9 nm resolution[J]. Proceedings of SPIE, 2015, 9422: 94221G. doi: 10.1117/12.2175488
[20]	CONLEY W, ALAGNA P, SHIEH J, et al. The impact of lower light source bandwidth on sub-10 nm process node features[J]. Proceedings of SPIE, 2017, 10147: 1014707.
[21]	RUOFF V D M J, NEUMANN J T, SCHMITT-WEAVER E, et al. Polarization-induced astigmatism caused by topographic masks[J]. Proceedings of SPIE, 2007, 6730: 67301T.
[22]	TANABE H, SATO S, TAKAHASHI A. Fast 3D lithography simulation by convolutional neural network[J]. Proceedings of SPIE, 2020, 11518: 115180L.
[23]	HAO Y Y, LI Y Q, LI T, et al. The calculation and representation of polarization aberration induced by 3D mask in lithography simulation[J]. Proceedings of SPIE, 2017, 10460: 104601J.
[24]	韦亚一. 超大规模集成电路先进光刻理论与应用[M]. 北京: 科学出版社, 2016: 103-105. WEI Y Y. Advanced Lithography Theory and Application for VLSI[M]. Beijing: Science Press, 2016: 103-105. (in Chinese)
[25]	AZPIROZ J T, ROSENBLUTH A E. Impact of sub-wavelength electromagnetic diffraction in optical lithography for semiconductor chip manufacturing[C]. Proceedings of the 2013 SBMO/IEEE MTT-S International Microwave & Optoelectronics Conference, IEEE, 2013: 1-5.
[26]	SAIED M, FOUSSADIER F, BELLEDENT J, et al. Three-dimensional mask effects and source polarization impact on OPC model accuracy and process window[J]. Proceedings of SPIE, 2007, 6520: 65204Q. doi: 10.1117/12.715120
[27]	YAN P Y. Understanding Bossung curve asymmetry and focus shift effect in EUV lithography[J]. Proceedings of SPIE, 2002, 4562: 279-287. doi: 10.1117/12.458302
[28]	ERDMANN A. Topography effects and wave aberrations in advanced PSM technology[J]. Proceedings of SPIE, 2001, 4346: 345. doi: 10.1117/12.435734
[29]	BURKHARDT M, RAGHUNATHAN A. Best focus shift mechanism for thick masks[J]. Proceedings of SPIE, 2015, 9422: 94220X.
[30]	NAKAJIMA Y, SATO T, INANAMI R, et al. Aberration budget in extreme ultraviolet lithography[J]. Proceedings of SPIE, 2008, 6921: 69211A.
[31]	ERDMANN A, EVANSCHITZKY P, FÜHNER T. Mask diffraction analysis and optimization for EUV masks[J]. Proceedings of SPIE, 2009, 7271: 72711E.
[32]	ERDMANN A, EVANSCHITZKY P, NEUMANN J T, et al. Mask-induced best-focus shifts in deep ultraviolet and extreme ultraviolet lithography[J]. Journal of Micro/Nanolithography, 2016, 15(2): 021205. doi: 10.1117/1.JMM.15.2.021205
[33]	HAQUE R R, LEVINSON Z, SMITH B W. 3D mask effects of absorber geometry in EUV lithography systems[J]. Proceedings of SPIE, 2016, 9776: 97760F.
[34]	MOCHI I, PHILIPSEN V, GALLAGHER E, et al. Assist features: placement, impact, and relevance for EUV imaging[J]. Proceedings of SPIE, 2016, 9776: 97761S. doi: 10.1117/12.2220025
[35]	BOUMA A, MIYAZAKI J, VAN VEEN M, et al. Impact of mask absorber and quartz over-etch on mask 3D induced best focus shifts[J]. Proceedings of SPIE, 2014, 9231: 92310S. doi: 10.1117/12.2068155
[36]	SZUCS A, PLANCHOT J, FARYS V, et al. Best focus shift mitigation for extending the depth of focus[J]. Proceedings of SPIE, 2013, 8683: 868313. doi: 10.1117/12.2011114
[37]	INOUE S, ITOH M, ASANO M, et al. Desirable reticle flatness from focus deviation standpoint in optical lithography[J]. Journal of Micro/Nanolithography,MEMS,and MOEMS, 2002, 1(3): 307. doi: 10.1117/1.1503806
[38]	LIU P, XIE X B, LIU W, et al. Fast 3D thick mask model for full-chip EUVL simulations[J]. Proceedings of SPIE, 2013, 8679: 86790W. doi: 10.1117/12.2010818
[39]	SEARS M K, SMITH B W. Modeling the effects of pupil-manipulated spherical aberration in optical nanolithography[J]. Journal of Micro/Nanolithography,MEMS,and MOEMS, 2013, 12(1): 013008. doi: 10.1117/1.JMM.12.1.013008
[40]	BRUNNER T A. Impact of lens aberrations on optical lithography[J]. IBM Journal of Research and Development, 1997, 41(1-2): 57-67.
[41]	BEKAERT J, VAN LOOK L, VANDENBERGHE G, et al. Characterization and control of dynamic lens heating effects under high volume manufacturing conditions[J]. Proceedings of SPIE, 2011, 7973: 79730V. doi: 10.1117/12.881609
[42]	LEVINSON H J. Principles of Lithography[M]. 3rd ed. Bellingham, WA: SPIE Press, 2011: 40-41.
[43]	李艳秋, 刘岩, 刘丽辉. 16 nm极紫外光刻物镜热变形对成像性能影响的研究[J]. 光学学报,2019,39(1):0122001. doi: 10.3788/AOS201939.0122001 LI Y Q, LIU Y, LIU L H. Effect of thermal deformation on imaging performance for 16 nm extreme ultraviolet lithography objective[J]. Acta Optica Sinica, 2019, 39(1): 0122001. (in Chinese) doi: 10.3788/AOS201939.0122001
[44]	SEARS M K, BEKAERT J, SMITH B W. Lens wavefront compensation for 3D photomask effects in subwavelength optical lithography[J]. Applied Optics, 2013, 52(3): 314-322. doi: 10.1364/AO.52.000314
[45]	HO G H, CHENG A, CHEN CH J, et al. Lens-heating-induced focus drift of I-line step and scan: correction and control in a manufacturing environment[J]. Proceedings of SPIE, 2001, 4344: 289-296. doi: 10.1117/12.436722
[46]	王帆, 王向朝, 马明英, 等. 光刻机投影物镜像差的现场测量技术[J]. 激光与光电子学进展,2004,41(6):33-37. WANG F, WANG X ZH, MA M Y, et al. In-situ measurement methods of lens aberration[J]. Laser &Optoelectronics Progress, 2004, 41(6): 33-37. (in Chinese)
[47]	CUI Y T. Fine-tune lens-heating-induced focus drift with different process and illumination settings[J]. Proceedings of SPIE, 2001, 4346: 1369-1378. doi: 10.1117/12.435675
[48]	CHANG Y S, WU M J, HUNG M Y, et al. Polygate within wafer CD uniformity improvement by the minimization of lens heating effect[J]. Proceedings of SPIE, 2001, 4404: 26-32. doi: 10.1117/12.425219
[49]	CHENG B J, LIU H CH, CUI Y T, et al. Improving image control by correcting the lens-heating focus drift[J]. Proceedings of SPIE, 2000, 4000: 818-826. doi: 10.1117/12.389075
[50]	LEE S H, SHROFF Y, CHANDHOK M. Flare and lens aberration requirements for EUV lithographic tools[J]. Proceedings of SPIE, 2005, 5751: 707-714. doi: 10.1117/12.604870
[51]	MONTCALM C, BAJT S, MIRKARIMI P B, et al. Multilayer reflective coatings for extreme-ultraviolet lithography[J]. Proceedings of SPIE, 1998, 3331: 42-51. doi: 10.1117/12.309600
[52]	FINDERS J. The impact of Mask 3D and Resist 3D effects in optical lithography[J]. Proceedings of SPIE, 2014, 9052: 905205.
[53]	PENG A, HSU S D, HOWELL R C, et al. Lithography-defect-driven source-mask optimization solution for full-chip optical proximity correction[J]. Applied Optics, 2021, 60(3): 616-620. doi: 10.1364/AO.408405
[54]	LIU X F, HOWELL R, HSU S, et al. EUV source-mask optimization for 7nm node and beyond[J]. Proceedings of SPIE, 2014, 9048: 90480Q. doi: 10.1117/12.2047584
[55]	WU Q. Key points in 14 nm photolithographic process development, challenges and process window capability[C]. Proceedings of 2017 China Semiconductor Technology International Conference, IEEE, 2017: 1-6.
[56]	JIA N N, YANG S H, KIM S, et al. Study of lens heating behavior and thick mask effects with a computational method[J]. Proceedings of SPIE, 2014, 9052: 905209.
[57]	王丽萍. 长春光机所承担的国家科技重大专项项目“极紫外光刻关键技术研究”通过验收[J]. 分析仪器,2017(4):96. WANG L P. The project of “study of key technology for extreme-ultraviolet lithography” passed the acceptance inspection[J]. Analytical Instrumentation, 2017(4): 96. (in Chinese)
[58]	DENG X J, CHAO A, FEIKES J, et al. Experimental demonstration of the mechanism of steady-state microbunching[J]. Nature, 2021, 590(7847): 576-579. doi: 10.1038/s41586-021-03203-0