超临界二氧化碳介质中晶圆清洗与选择性刻蚀研究进展

doi:10.11949/0438-1157.20230669

摘要/Abstract

摘要：

随着集成电路特征尺寸的逐渐减小，器件结构会要求更高的纵横比，常规湿法清洗由于表面张力很难进入晶圆深沟槽结构内部，不能满足更细线条工艺要求和高深宽比结构，直接影响沟槽内的污染物去除效果；常规湿法刻蚀各向异性差、结构坍塌严重、深沟槽刻蚀效果不明显；而等离子体干法刻蚀则存在刻蚀速率慢、光刻胶脱落和黏附、结构损伤、废气处理等一系列问题。超临界清洗和刻蚀技术是最具有前景的环境友好、无损伤技术，能够耦合刻蚀、清洗与干燥工艺为一体，且可以循环使用，安全环保，是晶圆制造过程中常规清洗和刻蚀的首选替代技术。综述了超临界二氧化碳中晶圆清洗与选择性刻蚀的研究进展，重点介绍了超临界二氧化碳共溶剂、微乳液体系在光刻胶剥离以及含硅基底选择性蚀刻中的应用，展望了超临界二氧化碳晶圆清洗和刻蚀存在的问题和发展趋势。

关键词: 晶圆清洗, 晶圆刻蚀, 超临界二氧化碳, 超临界流体, 微乳液

Abstract:

With the gradual reduction of the feature size of integrated circuits, the device structure will require higher aspect ratios. Due to the surface tension, it is difficult for conventional wet cleaning to enter the deep trench structure of the wafer, which cannot meet the requirements of finer line technology and high aspect ratio. The structure directly affects the pollutant removal effect in the trench. Conventional wet etching methods exhibit poor anisotropy, significant structure collapse, and ineffective etching of deep trenches. On the other hand, plasma dry etching techniques suffer from slow etching rates, photoresist detachment and adhesion, structural damage, and exhaust gas treatment issues. Supercritical cleaning and etching techniques have emerged as the most promising environmentally-friendly and non-damaging alternatives with the ability of integrating etching, cleaning, and drying processes. Moreover, they can be recycled, ensuring safety and environmental sustainability. This review summarizes the progress in wafer cleaning and selective etching using supercritical carbon dioxide, focusing on the applications of supercritical carbon dioxide cosolvent and microemulsion systems in photoresist stripping and selective etching on silicon-based substrates. Finally, the challenges and development trends of wafer cleaning and etching using supercritical carbon dioxide are discussed.

Key words: wafer cleaning, wafer etching, supercritical carbon dioxide, supercritical fluid, microemulsion

中图分类号:

TN 305.97

张泽欣, 郑伟中, 徐益升, 胡冬冬, 卓欣宇, 宗原, 孙伟振, 赵玲. 超临界二氧化碳介质中晶圆清洗与选择性刻蚀研究进展[J]. 化工学报, 2024, 75(1): 110-119.

Zexin ZHANG, Weizhong ZHENG, Yisheng XU, Dongdong HU, Xinyu ZHUO, Yuan ZONG, Weizhen SUN, Ling ZHAO. Research progress of wafer cleaning and selective etching in supercritical carbon dioxide media[J]. CIESC Journal, 2024, 75(1): 110-119.

图/表 7

参考文献 45

1	刘建丽. 美国《芯片与科学法案》的可能影响及中国的应对之策[J]. 中国发展观察, 2022(12): 116-120.
	Liu J L. The possible impact of the chip and science act of the United States and China's countermeasures[J]. China Development Observation, 2022(12): 116-120.
2	Chen J L, Wang Y S, Kuo H I, et al. Stripping of photoresist on silicon wafer by CO₂ supercritical fluid[J]. Talanta, 2006, 70(2): 414-418.
3	李俊岭, 康冬妮. 超临界CO₂清洗在半导体工业中的应用[J]. 国防制造技术, 2013(5): 34-37.
	Li J L, Kang D N. Supercritical CO₂ cleaning applications in the semiconductor industry[J]. Defense Manufacturing Technology, 2013(5): 34-37.
4	Weibel G L, Ober C K. An overview of supercritical CO₂ applications in microelectronics processing[J]. Microelectronic Engineering, 2003, 65(1/2): 145-152.
5	Lee D H, Chung M J, Hwang H K, et al. Etch damage evaluation of low-angle, forward-reflected neutral beam etching[J]. Materials Science and Engineering: C, 2003, 23(1/2): 221-224.
6	Kern W. Cleaning solutions based on hydrogen peroxide for use in silicon semiconductor technology[J]. RCA Review, 1970, 31(2):187-206.
7	Vig J R. UV/ozone cleaning of surfaces[J]. Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 1985, 3(3): 1027-1034.
8	张小岗, Johnston Keith P.. 超临界二氧化碳溶液体系集成处理新一代微电子器件研究进展[J]. 科学通报, 2006, 51(20): 2347-2352.
	Zhang X G, Keith P J. Research progress of integrated treatment of new generation microelectronic devices in supercritical carbon dioxide solution system[J]. Chinese Science Bulletin, 2006, 51(20): 2347-2352.
9	Spierings G A C M. Wet chemical etching of silicate glasses in hydrofluoric acid based solutions[J]. Journal of Materials Science, 1993, 28(23): 6261-6273.
10	Ferstl M. Highly selective etching of deep silica components using electron cyclotron resonance plasma[J]. Microelectronic Engineering, 2002, 61/62: 881-886.
11	王晨飞. 半导体工艺中的新型刻蚀技术: ICP[J]. 红外, 2005, 26(1): 17-22.
	Wang C F. A new etching technology in semiconductor technology—ICP[J]. Infrared, 2005, 26(1): 17-22.
12	Jung S T, Song H S, Kim D S, et al. Inductively coupled plasma etching of SiO₂ layers for planar lightwave circuits[J]. Thin Solid Films, 1999, 341(1/2): 188-191.
13	Yamada H, Kuwahara K, Fujiyama H. SiO₂ etching characteristics in DC magnetron plasmas by using an external magnetic field[J]. Thin Solid Films, 1998, 316(1/2): 6-12.
14	彭英利,马承愚. 超临界流体技术应用手册[M]. 北京: 化学工业出版社, 2005.
	Peng Y L, Ma C Y. Supercritical Fluid Technology Application Manual[M]. Beijing: Chemical Industry Press, 2005.
15	Tanaka M, Rastogi A, Toepperwein G N, et al. Fluorinated quaternary ammonium salts as dissolution aids for polar polymers in environmentally benign supercritical carbon dioxide[J]. Chemistry of Materials, 2009, 21(14): 3125-3135.
16	韩布兴. 超临界流体科学与技术[M]. 北京: 中国石化出版社, 2005.
	Han B X. Supercritical Fluid Science & Technology[M]. Beijing: China Petrochemical Press, 2005.
17	李颖. 超临界CO₂包离子液体型微乳液的分子模拟[D]. 大连: 大连理工大学, 2017.
	Li Y. Molecular simulation of ionic liquid microemulsion in supercritical CO₂ [D]. Dalian: Dalian University of Technology, 2017.
18	任泓睿. 4FG(EO)₂表面活性剂构建液态或超临界二氧化碳微乳液的分子动力学模拟研究[D]. 大连: 大连理工大学, 2021.
	Ren H R. Molecular dynamics simulation of liquid or supercritical carbon dioxide microemulsion constructed by 4FG(EO)₂ surfactant[D]. Dalian: Dalian University of Technology, 2021.
19	喻文. 超临界CO₂微乳液相行为、微观结构及应用研究[D]. 大连: 大连理工大学, 2015.
	Yu W. Study on phase behavior, microstructure and application of supercritical CO₂ microemulsion[D]. Dalian: Dalian University of Technology, 2015.
20	朱宏跃. 超临界CO₂及其包离子液体微乳液剥离制备石墨烯过程基础研究[D]. 大连: 大连理工大学, 2021.
	Zhu H Y. Fundamental research on the process of exfoliating graphene by supercritical CO₂ and supercritical CO₂ microemulsion containing ionic liquid [D]. Dalian: Dalian University of Technology, 2021.
21	Liu J C, Han B X, Li G Z, et al. Investigation of nonionic surfactant dynol-604 based reverse microemulsions formed in supercritical carbon dioxide[J]. Langmuir, 2001, 17(26): 8040-8043.
22	Liu J C, Han B X, Wang Z W, et al. Solubility of ls-36 and ls-45 surfactants in supercritical CO₂ and loading water in the CO₂/water/surfactant systems[J]. Langmuir, 2002, 18(8): 3086-3089.
23	Liu J C, Han B X, Zhang J L, et al. Formation of water-in-CO₂ microemulsions with non-fluorous surfactant ls-54 and solubilization of biomacromolecules[J]. Chemistry-A European Journal, 2002, 8(6): 1356-1360.
24	Saga K, Kuniyasu H, Hattori T, et al. Etching of silicon oxide films in supercritical carbon dioxide[J]. Solid State Phenomena, 2005, 103/104: 115-120.
25	Lee M Y, Do K M, Ganapathy H S, et al. Surfactant-aided supercritical carbon dioxide drying for photoresists to prevent pattern collapse[J]. The Journal of Supercritical Fluids, 2007, 42(1): 150-156.
26	Visintin P M, Michael B K, Baum T H, et al. The removal of ion-implanted photoresist from microelectronic devices using supercritical carbon dioxide [C]// Proceedings of the 2005 Annual Meeting. Cincinnati: AIChE, 2005.
27	王磊, 景玉鹏. 高温高压水辅助的超临界二氧化碳剥离光刻胶的装置及方法: 102346381A[P]. 2012-02-08.
	Wang L, Jing Y P. Apparatus and method for peeling photoresist by high temperature and high pressure water assisted supercritical carbon dioxide: 102346381A[P]. 2012-02-08.
28	Korzenski M B, Kolis J W. Diels-Alder reactions using supercritical water as an aqueous solvent medium[J]. Tetrahedron Letters, 1997, 38(32): 5611-5614.
29	Myneni S, Hess D W. Post-plasma-etch residue removal using CO₂-based fluids[J]. Journal of the Electrochemical Society, 2003, 150(12): G744.
30	Levitin G, Myneni S, Hess D W. Post plasma etch residue removal using CO₂-TMAHCO₃ mixtures: comparison of single-phase and two-phase mixtures[J]. Journal of the Electrochemical Society, 2004, 151(6): G380.
31	Kim D W, Heo H, Lim K T. Study of supercritical carbon dioxide/n-butyl acetate co-solvent system with high selectivity in photoresist removal process[J]. Clean Technology, 2017, 23(4): 357-363.
32	Kim S H, Yuvaraj H, Jeong Y T, et al. The effect of ultrasonic agitation on the stripping of photoresist using supercritical CO₂ and co-solvent formulation[J]. Microelectronic Engineering, 2009, 86(2): 171-175.
33	You S S. Removal of post etch/ash residue on an aluminum patterned wafer using supercritical CO₂ mixtures with co-solvents and surfactants: sc-CO₂ mixture for the removal of post etch/ash residue[J]. Journal of the Semiconductor & Display Technology, 2017, 16(1): 22-28.
34	Yoon S I, Park Y W, Oh C I, et al. Photoresist remover composition: US6908892[P]. 2005-06-21.
35	Chang T F M, Ishiyama C, Sato T, et al. Quantitative study on removal of SU-8 photoresist patterns by supercritical CO₂ emulsion[J]. Microelectronic Engineering, 2013, 110: 204-206.
36	Zhang X G, Pham J Q, Martinez H J, et al. Water-in-carbon dioxide microemulsions for removing post-etch residues from patterned porous low-k dielectrics[J]. Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena, 2003, 21(6): 2590-2598.
37	Han T T, Li B, Wang Q P, et al. High-dose ion-implanted photoresist stripping in environmentally benign supercritical CO₂ nonfluorous surfactant microemulsions[J]. Microelectronic Engineering, 2012, 96: 1-5.
38	戴剑锋, 孙毅彬, 张超, 等. 采用超临界CO₂流体清除硅芯片上的纳米粒子[J]. 纳米技术与精密工程, 2009, 7(1): 20-24.
	Dai J F, Sun Y B, Zhang C, et al. Removal of nanoparticles on silica wafer by supercritical fluid carbon dioxide[J]. Nanotechnology and Precision Engineering, 2009, 7(1): 20-24.
39	高公如, 韩斌, 张学春, 等. 超声波辅助超临界CO₂清洗精密零部件设备设计[J]. 农业装备与车辆工程, 2013, 51(3): 42-44.
	Gao G R, Han B, Zhang X C, et al. Design of precision parts cleaning equipment using supercritical carbon dioxide assisted with ultrasound[J]. Agricultural Equipment & Vehicle Engineering, 2013, 51(3): 42-44.
40	Jones C A, Yang D X, Irene E A, et al. HF etchant solutions in supercritical carbon dioxide for "dry" etch processing of microelectronic devices[J]. Chemistry of Materials, 2003, 15(15): 2867-2869.
41	Li Y X, Yang D, Jones Ⅲ C A, et al. Etching SiO₂ with HF/pyridine-supercritical carbon dioxide solutions and resultant interfacial electronic properties[J]. Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures Processing, Measurement, and Phenomena, 2007, 25(4): 1139-1142.
42	Malhouitre S, van Hoeymissen J, Case C, et al. Etching of thermal SiO₂ in supercritical CO₂ [J]. ECS Transactions, 2007, 11(2): 71-78.
43	Hwang H S, Bae J H, Jung J M, et al. The sacrificial oxide etching of poly-Si cantilevers having high aspect ratios using supercritical CO₂ [J]. Microelectronic Engineering, 2010, 87(9): 1696-1700.
44	Bae J H, Alam M Z, Jung J M, et al. Improved etching method for microelectronic devices with supercritical carbon dioxide[J]. Microelectronic Engineering, 2009, 86(2): 128-131.
45	Min S K, Han G S, You S S. Continuous process for the etching, rinsing and drying of MEMS using supercritical carbon dioxide[J]. Korean Chemical Engineering Research, 2015, 53(5): 557-564.

编辑推荐 0

Metrics

阅读次数

全文

1117

HTML			PDF

最新录用	在线预览	正式出版	最新录用	在线预览	正式出版
5	0	48	167	0	897

来源	本网站	其他网站

次数	332	785
比例	30%	70%

摘要

692

最新录用	在线预览	正式出版

84	0	608

来源	本网站	其他网站

次数	123	569
比例	18%	82%

表面活性剂	助溶剂	比例	浓度	反应条件	清洗效率/%	光刻胶种类	文献
EH-3	DMSO	—	3%（质量） EH-3 2%(体积)DMSO	60℃，25 MPa， 10 min	100	高浓度离子注入的BP-12	[37]
PFOA	SMS50L、EtOH	SMS50L∶EtOH∶PFOA= 7.1%∶10.4%∶82.5%（质量）	13.6%(体积)	40~80℃， 130~250 bar	—	—	[33]
PFOA	MEA、1M2P、EtOH	MEA∶1M2P∶EtOH∶PFOA= 2.5%∶1.7%∶13.1%∶82.7%（质量）	13.6%(体积)
PFOA	MEA、1M2P、EtOH	MEA∶1M2P∶EtOH∶PFOA= 4.9%∶1.2%∶9.5%∶84.4%（质量）	18.2%(体积)
RM258	SMS50L、EtOH	SMS50L∶EtOH∶RM= 6.1%∶7.4%∶86.5%（质量）	17.1%(体积)
PFHA	SMS50L、EtOH	SMS50L∶EtOH∶PFHA= 7.1%∶10.4%∶82.5%（质量）	13.6%(体积)
—	DMSO	—	10%(质量)	70℃，27.6 MPa， 180 s，超声	100	高浓度离子注入后的KrF光刻胶	[32]
POLE	水	CO₂∶POLE∶H₂O= 20.00%∶0.16%∶79.84%(体积)	—	50℃，15 MPa， 30 min	42.1	高温烘烤后SU-8 光刻胶（负性）	[35]
—	乙酸正丁酯	—	75%(质量)	40℃，160 bar， 10 min		未曝光的负性光刻胶	[31]
—	TMAHCO₃，甲醇	TMAHCO₃∶甲醇= 0.58%∶23.70%(摩尔)	20.68%(摩尔)	70℃，3000 psi， 15 min		碳氟等离子体刻蚀后的PHOST	[30]
—	QAS-4	—	1.25 mmol/L	50℃，5000 psi		PBOCST	[15]

表面活性剂	助溶剂	比例	浓度	反应条件	清洗效率/%	光刻胶种类	文献
EH-3	DMSO	—	3%（质量） EH-3 2%(体积)DMSO	60℃，25 MPa， 10 min	100	高浓度离子注入的BP-12	[37]
PFOA	SMS50L、EtOH	SMS50L∶EtOH∶PFOA= 7.1%∶10.4%∶82.5%（质量）	13.6%(体积)	40~80℃， 130~250 bar	—	—	[33]
PFOA	MEA、1M2P、EtOH	MEA∶1M2P∶EtOH∶PFOA= 2.5%∶1.7%∶13.1%∶82.7%（质量）	13.6%(体积)
PFOA	MEA、1M2P、EtOH	MEA∶1M2P∶EtOH∶PFOA= 4.9%∶1.2%∶9.5%∶84.4%（质量）	18.2%(体积)
RM258	SMS50L、EtOH	SMS50L∶EtOH∶RM= 6.1%∶7.4%∶86.5%（质量）	17.1%(体积)
PFHA	SMS50L、EtOH	SMS50L∶EtOH∶PFHA= 7.1%∶10.4%∶82.5%（质量）	13.6%(体积)
—	DMSO	—	10%(质量)	70℃，27.6 MPa， 180 s，超声	100	高浓度离子注入后的KrF光刻胶	[32]
POLE	水	CO₂∶POLE∶H₂O= 20.00%∶0.16%∶79.84%(体积)	—	50℃，15 MPa， 30 min	42.1	高温烘烤后SU-8 光刻胶（负性）	[35]
—	乙酸正丁酯	—	75%(质量)	40℃，160 bar， 10 min		未曝光的负性光刻胶	[31]
—	TMAHCO₃，甲醇	TMAHCO₃∶甲醇= 0.58%∶23.70%(摩尔)	20.68%(摩尔)	70℃，3000 psi， 15 min		碳氟等离子体刻蚀后的PHOST	[30]
—	QAS-4	—	1.25 mmol/L	50℃，5000 psi		PBOCST	[15]

刻蚀剂	温度/℃	HF浓度/(mmol/L)	压力	时间/min	刻蚀样品	文献
70%∶30%（质量） HF/吡啶	40~75	2~15	140 bar	2~20	SiO₂	[40]
63%∶27%∶10%（质量） HF/吡啶/异丙醇	55	0.2~2.0	20.7MPa	3	BPSG、P-TEOS、SiO₂、SiN	[44]

刻蚀剂	温度/℃	HF浓度/(mmol/L)	压力	时间/min	刻蚀样品	文献
70%∶30%（质量） HF/吡啶	40~75	2~15	140 bar	2~20	SiO₂	[40]
63%∶27%∶10%（质量） HF/吡啶/异丙醇	55	0.2~2.0	20.7MPa	3	BPSG、P-TEOS、SiO₂、SiN	[44]

[1]	张义飞, 刘舫辰, 张双星, 杜文静. 超临界二氧化碳用印刷电路板式换热器性能分析[J]. 化工学报, 2023, 74(S1): 183-190.
[2]	洪瑞, 袁宝强, 杜文静. 垂直上升管内超临界二氧化碳传热恶化机理分析[J]. 化工学报, 2023, 74(8): 3309-3319.
[3]	姚晓宇, 沈俊, 李健, 李振兴, 康慧芳, 唐博, 董学强, 公茂琼. 流体气液临界参数测量方法研究进展[J]. 化工学报, 2023, 74(5): 1847-1861.
[4]	朱兵国, 何吉祥, 徐进良, 彭斌. 冷却条件下渐扩/渐缩管内超临界压力二氧化碳的传热特性[J]. 化工学报, 2023, 74(3): 1062-1072.
[5]	赫一凡, 于帅, 闫兴清, 喻健良. 基于特征线法的CO₂减压波传播模型构建及止裂壁厚研究[J]. 化工学报, 2023, 74(12): 5038-5047.
[6]	许婉婷, 许波, 王鑫, 陈振乾. 方形微通道内超临界CO₂流动换热特性研究[J]. 化工学报, 2022, 73(4): 1534-1545.
[7]	孙铭泽, 马宁, 李浩然, 姜海峰, 洪文鹏, 牛晓娟. 中低温超临界CO₂及其混合工质布雷顿循环热力学分析[J]. 化工学报, 2022, 73(3): 1379-1388.
[8]	汪森林, 李照志, 邵应娟, 钟文琪. 超临界二氧化碳垂直管内传热恶化数值模拟研究[J]. 化工学报, 2022, 73(3): 1072-1082.
[9]	王彦红, 陆英楠, 李素芬, 东明. U形圆管中超临界压力RP-3航空煤油换热数值研究[J]. 化工学报, 2021, 72(9): 4639-4648.
[10]	颜建国, 郑书闽, 郭鹏程, 张博, 毛振凯. 基于GA-BP神经网络的超临界CO₂传热特性预测研究[J]. 化工学报, 2021, 72(9): 4649-4657.
[11]	严如奇, 丁雪兴, 徐洁, 洪先志, 包鑫. 基于湍流模型的S-CO₂干气密封流场与稳态性能分析[J]. 化工学报, 2021, 72(8): 4292-4303.
[12]	洪燕珍, 王笛, 李卓昱, 徐亚南, 王宏涛, 苏玉忠, 彭丽, 李军. 超临界二氧化碳介入的α-松油醇催化合成1，8-桉叶素[J]. 化工学报, 2021, 72(7): 3680-3685.
[13]	王艳, 徐进良, 李文. 不同种类超临界流体异质结构及相变分析[J]. 化工学报, 2021, 72(4): 1906-1919.
[14]	江锦波, 滕黎明, 孟祥铠, 李纪云, 彭旭东. 基于多变量摄动的超临界CO₂干气密封动态特性[J]. 化工学报, 2021, 72(4): 2190-2202.
[15]	王彦红, 陆英楠, 李素芬, 东明. 周向非均匀加热水平圆管内超临界正癸烷换热特性[J]. 化工学报, 2021, 72(3): 1342-1353.