极紫外光刻胶产气的定性和定量检测  

Qualitative and Quantitative Measurement of Outgassing of Molecular Glass Photoresists under ExtremeUltraviolet Lithography

作　　者：陈金平[1] 郝青山[1] 王双青[2] 杨树敏 赵俊 吴衍青 曾毅[1,4] 于天君 杨国强[2,4] 李嫕[1,4] CHEN Jin-Ping;HAO Qing-Shan;WANG Shuang-Qing;YANG Shu-Min;ZHAO Jun;WU Yan-Qing;ZENG Yi;YU Tian-Jun;YANG Guo-Qiang;LI Yi(Key Laboratory of Photochemical Conversion and Optoelectronic Materials,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;Beijing National Laboratory for Molecular Sciences,CAS Key Laboratory of Photochemistry,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China;Shanghai Synchrotron Radiation Facility,Shanghai Advanced Research Institute,Chinese Academy of Sciences,Shanghai 201204,China;University of Chinese Academy of Sciences,Beijing 100039,China)

机构地区：[1]中国科学院理化技术研究所光化学转换与功能材料重点实验室,北京100190 [2]中国科学院化学研究所光化学重点实验室,北京100190 [3]中国科学院上海高等研究院上海同步辐射光源,上海201204 [4]中国科学院大学,北京100039

出　　处：《分析化学》2020年第12期1658-1665,共8页Chinese Journal of Analytical Chemistry

基　　金：国家科技重大专项(Nos.2018ZX02102005,2011ZX02701)资助。

摘　　要：利用压强升高法建立了极紫外(Extreme ultraviolet,EUV)光刻胶产气检测系统,对以分子玻璃(Molecular glass)螺芴(9,9′-Spirobifluorene,SP)为主体材料的光刻胶薄膜体系Film A、B、C和D进行产气的定性和定量分析,其中,Film A的主体材料外围取代基团为叔丁氧羰基(t-Butylcarbonyl,Boc),Film B和C是在Film A光刻胶薄膜顶层覆盖不同厚度的保护层,Film D的主体材料外围取代基团为醋酸金刚烷酯(Adamantyl acetate,Ad)。采用四极杆质谱检测光刻胶薄膜在EUV曝光条件的产气组分,结果表明,Film A产气的主要来源为光照产生的酸催化光刻胶主体材料脱Boc取代基反应释放的异丁烯(C 4H 8)和CO 2气体,以及少量由于产酸剂(Photo-acid generator,PAG)分解释放的苯类挥发性组分。覆盖保护层的Film B、C产气成分与Film A类似,但各离子峰的丰度明显降低。Film D的质谱图上显示气体释放成分为CO 2和极微量的金刚烷类取代基的碎片峰。通过高精度真空规定量分析不同薄膜的产气量,原位实时检测结果表明,光刻胶薄膜产气速率在曝光初始阶段最快,而后逐渐变缓或趋于稳定,表明光刻胶薄膜表面的分子在EUV光照更容易释放气体。对比Film A和Film B、C体系发现,顶层覆盖可以显著降低光刻胶的产气速率和产气量,增加顶层覆盖厚度,抑制产气效果更明显,在Film A顶层覆盖厚度30 nm的保护层,10 mJ/cm^2曝光剂量下,产气量从1.19×10^15 molecule/cm 2降低到2.35×10^14 molecule/cm^2,降低了约5倍,证明顶层覆盖是降低光刻胶薄膜产气的有效方法。不同取代基团的主体材料形成的光刻胶薄膜Film D和Film A在EUV曝光中的产气差别明显,Film D的产气速率和产气量比Film A降低了10倍以上,表明光刻胶主体材料的外围取代基团对光刻胶薄膜的产气量具有显著影响,更大分子量和更高脱保护反应活化能的取代基团有助于降低光刻胶薄膜的产气量。A system was set up for quantitative and qualitative analysis of outgassing of photoresists using pressure rise method.The outgassing of molecular glass photoresist films(Film A,B,C and D)based on 9,9′-spirobifluorene(SP)derivatives was evaluated by the system.Film A was formed by SP with substituent group of tert-butyloxycarbonyl(Boc),and Film B and C were prepared by covering Film A with top-coating material in different thicknesses.Film D was formed by SP with substituent group of adamantyl acetate(Ad).The components of residual gas during the EUV irradiation were detected by the quadruple mass spectrometer(QMS).In the case of Film A,it showed that the source of the outgassing was mainly from the acid catalytic reaction of substituent of Boc group,releasing isobutylene(C 4H 8)and CO 2 gas,along with a small amount of benzene component produced by the decomposition of photo acid generator(PAG).Film B and C,covered with protective layer,were similar to that of film A,but the ion abundance decreased obviously.Ion peak of CO 2 molecule and the fragment peaks of adamantane substituent were observed in mass spectra of Film D.The amount of outgassing for different films was analyzed in-situ by an ion gauge,and it was found that the rate of outgassing was fast in the initial stage of exposure,and then slow down,suggesting that the molecules on the surface of the films were more likely to release gas.Besides,the top-coating could significantly reduce the rate of outgassing comparing the results of Film A and Film B/C,for instance,the outgassing could be reduced from 1.19×10^15 molecule/cm^ 2 to 2.35×10^14 molecule/cm^ 2 under the exposure dose of 10 mJ/cm ^2 by covering with 30-nm thickness of top-coating material,suggesting that the top-coating was an effective method to reduce outgassing.By comparing the outgassing of Film D and Film A that was formed by the resist materials with different peripheral substituent groups,it was found that the outgassing of Film D was decreased by 10 times than that of Film A,indica

关 键 词：光刻胶 产气 分子玻璃 极紫外 光刻 

分 类 号：TN23[电子电信—物理电子学] TN305.7