浸没式光刻投影物镜光学薄膜

毕丹丹; 张立超; 时光

doi:10.3788/CO.20181105.0745

浸没式光刻投影物镜光学薄膜

毕丹丹^{1, 2,},
张立超^{1, 3, ,},
时光^{1, 3,}

1.
中国科学院长春光学精密机械与物理研究所超精密光学工程研究中心, 吉林长春 130039
2.
中国科学院大学, 北京 100049
3.
长春国科精密光学技术有限公司, 吉林长春 130039

基金项目:

国家科技重大专项资助项目 2009ZX02205

详细信息

作者简介:
毕丹丹(1992-), 女, 吉林省吉林市人, 硕士研究生, 现为中国科学院长春光学精密机械与物理研究所在读硕士, 主要从事光学薄膜技术方面的研究。E-mail:bidandan15@mails.ucas.ac.cn

张立超(1979—)，男，吉林省吉林市人，博士，研究员，2000年、2003年于吉林大学分别获得学士、硕士学位，2007年于中国科学院长春光学精密机械与物理研究所获得博士学位，主要从事光学薄膜技术方面的研究。E-mail:zhanglic@klao.ac.cn

时光(1985—)，女，黑龙江省鸡西人，硕士，助理研究员，2008年、2011年于电子科技大学分别获得学士、硕士学位，主要从事深紫外光学薄膜方面的研究。E-mail:nrconnie@163.com

中图分类号: O484
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出版历程
- 收稿日期: 2017-10-20
- 修回日期: 2017-12-15
- 刊出日期: 2018-10-01

Optical coatings for projection objective immersion lithography

doi: 10.3788/CO.20181105.0745

BI Dan-dan^{1, 2
,},
ZHANG Li-chao^{1, 3
, ,},
SHI Guang^{1, 3
,}

1.
Engineering Research Center of Extreme Precision Optics, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130039, China
2.
University of Chinese Academic of Sciences, Beijing 100049, China
3.
Changchun National Extreme Precision Optics Co. Ltd., Changchun 130039, China

Funds:

the National Science and Technology Major Project of the Ministry of Science and Technology of China 2009ZX02205

More Information

Author Bio:
BI Dan-dan(1992—), female, born in the city of Jilin, Jilin Province, who is a master-degree student studying at Changchun Institute of Optics, Fine Mechanics and Physics under Chinese Academy of Sciences and is mainly engaged in the optical coating technology research. E-mail:bidandan15@mails.ucas.ac.cn

ZHANG Li-chao(1979—), male, born in the city of Jilin, Jilin Province, who is a doctor-degree researcher with bachelor and master degrees from Jilin University obtained respectively in 2000 and 2003 as well as the doctor degree from Changchun Institute of Optics, Fine Mechanics and Physics under Chinese Academy of Sciences and is mainly engaged in the optical coating technology research. E-mail: zhanglic@klao.ac.cn

SHI Guang(1985—), female, born in the city of Jixi, Heilongjiang Province, who is an assistant researcher with bachelor and master degrees from University of Electronic Science and Technology of China obtained respectively in 2008 and 2011 and is mainly engaged in the deep ultraviolet optical coating research. E-mail:nrconnie@163.com

Corresponding author: ZHANG Li-chao, E-mail:zhanglc@sklao.ac.cn

摘要

摘要: 深紫外光刻是目前集成电路制造的主流方法，为实现更小的元件特征尺寸，必须采用浸没式投影物镜以提高光学系统的分辨率，由此向其中的薄膜光学元件提出了众多苛刻的要求。本文介绍了适用于浸没式光刻系统的薄膜材料及膜系设计，以及高NA光学系统所需的大角度保偏膜系；对物镜中最关键的浸液薄膜的液体环境适应性、疏水及防污染等关键问题进行了讨论；对衡量浸没式光刻系统性能的重要因素镀膜元件激光辐照寿命，尤其是浸液环境下的元件辐照寿命进行了分析。
- 浸没式光刻 /
- 光学薄膜 /
- 膜系设计 /
- 环境适应性 /
- 激光辐照寿命
Abstract: The deep ultraviolet lithography is currently a main method for integrated circuit manufacture. The immersive projection objective must be used to increase resolution of the optical system for realization of smaller component feature dimensions. Therefore a number of rigorous requirements for optical coating component are put forward. In this paper we present designs of the film material and film system applicable to immersive lithographical system as well as the large angle polarization-maintaining film system required for optical systems at high NA. Key issues about immersion environment adaptability, hydrophobicity and anti-contamination of the immersion coating most critical to the objective are discussed. Laser irradiation lifetime of the coated components especially in the immersion environment that is an important factor to evaluate performance of the immersive lithographical system is analyzed.
- immersion lithography /
- optical coatings /
- coating system design /
- environmental adaptability /
- lifetime under laser irradiation

HTML全文

图 1 五层减反射膜系反射率与最外层材料折射率的关系。五层膜系，其中仅最外层材料折射率发生变化

Figure 1. Simulated relation between the refractive index of the top layer of an five-layer-antireflective coating and the reflectance. stack, five layers(only the refractive index of the top layer was changed)

下载: 全尺寸图片幻灯片

图 2 两种溶胶(MgF₂和SiO₂)不同Si/Mg摩尔比混合实现可调折射率

Figure 2. Realization of the adjustable refraction index with mixture of two sols (MgF₂ and SiO₂) at different Si/Mg molar ratios

下载: 全尺寸图片幻灯片

图 3 (a)常用光刻物镜下窗口元件；(b)膜层材料的接触角

Figure 3. (a) Last optical element of the lithography objective; (b)Contact angle of the film layer material

下载: 全尺寸图片幻灯片

图 4 通过表面修饰提高材料表面疏水性能

Figure 4. Increase of the material surface hydrophobicity with surface trimming

下载: 全尺寸图片幻灯片

图 5 激光辐照过程中在线透过率检测光路图

Figure 5. Optical path of in-situ transmission measurement while laser irradiation

下载: 全尺寸图片幻灯片

图 6 元件不可逆损伤的数值与重复频率、能量密度的关系

Figure 6. Relationship between the value of irreversible component damage and the repetitive frequency and energy density

下载: 全尺寸图片幻灯片

图 7 (a)镀膜元件在激光辐照后的空间Delta分布；(b)激光辐照样品

Figure 7. (a) Delta space distribution for the film-coated component after laser irradiation; (b)Laser irradiation sample

下载: 全尺寸图片幻灯片

图 8 膜层动态减薄模型透过率(实线)与辐照过程中实测透过率(散点)关系

Figure 8. Relationship between the transmittance(solid lines) in dynamic film-layer thinning model and the transmittance(scattered points) measured actually during irradiation

下载: 全尺寸图片幻灯片

表 1 System indices corresponding to different schemes

Table 1. System indices corresponding to different schemes

Index requirement	System index	Regular film system	Combined film system	Combined BAAR film system that includes film layers with an extremely low refraction index
Retardation/(RMS, nm)	< 2.00	2.69	2.29	1.94
Diattenuation(RMS)	< 0.005	0.009	0.015	0.010
Apodization uniformity	> 0.90	0.79	0.89	0.94
Transmittance	> 0.60	0.69	0.55	0.67

下载: 导出CSV

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