Resist Characteristics in EUVL

Transcription

1 Resist Characteristics in EUVL - Mitigation of hydrocarbon outgassing species & LER in CA resist - Takeo Watanabe 1, Kazuhiro Hamamoto 1, Hiroo Kinoshita 1, Hideo Hada 2, and Hiroshi Komano 2 1 Laboratory of Advanced Science and Technology for Industry, Himeji Institute of Technology 2 Advanced Material Development Division 1, Tokyo hka Kogyo Co. takeo@lasti.himeji-tech.ac.jp

2 utline 1. Introduction 2. Experimental Setup 3. Result and Discussion 4. Conclusion

3 120 nm L&S pattern Replication characteristics KrF-A KrF-B EB-A EB-B ZEP nm L&S pattern KrF-A KrF-B EB-A EB-B ZEP520

4 Resist characteristics Name Type Sensitivity (mj/cm 2 ) Resolution (nm) LER (nm) utgassing (Pa) Kr-A KrF-CA x10-7 Kr-B KrF-CA x10-7 EB-A EB-CA x10-8 EB-A EB-CA x10-8 ZEP520 EB non-ca x10-7

5 Mitigation of hydrocarbon outgassing species & LER in CA resist Non CA resist CA resist Main chain decomposition type (DQN, ZEP520etc.) LER Sensitivity utgassing PHS high annealing type (KrF type) Main chain decomposition type & CA resist (Polymer: Methacrylate)

6 Samples employed for the outgassing meas. utgas test exposure conditions HIT EUV (120mA, with Mo / Si mirror) Samples polymer EUV001 KrF PHS + tbu-acrylate EUV308 KrF PHS + acrylate EUV310 EUV311 EUV312 ArF Methacryl polymer1 ArF Methacryl polymer2 ArF Methacryl polymer3

7 EUV310 series structures Sample name Polymer PAG Quencher Solvent EUV-310 EUV-311 S+ CnF2n+1S3- (EtH)3N PGMEA / GBL 0.3% (vs resin) 90 / 10 C=4.5% (vs resin) EUV-312 Et H

8 Beamline setup for resist outgassing experiment New SUBARU Storage Ring M1 M2 Collimating ptics Shield 4WS & Filter Resist Test Chamber C1 C2 Illumination ptics Exposure Chamber

9 SR Resist chamber C1 mirror chamber C2 mirror chamber

10 Experimental setup Resist test chamber Quadrupole mass spectrometer utgassing species Sample EUV Mo/Si multilayer mirror

11 Mo/Si multilayer reflectivity Incident angle : 10.0 deg. 0.5 Reflectivity Wavelength (nm)

12 Results (EUV001 vs EUV308) EUV001 EUV mA (Mo/ Si ML) EUV308 EUV mA (Mo/ Si ML) Tbu ester tbu ester Protecting Gr mass number Mass number n m o A B C H Any Iodonium salt PAG H R 1 R 1 =Mw 111 Short summary ; Ester ratio : EUV001 = 15% EUV308 = 30% Iodonium salt PAG

13 Partial pressure displacement of EUV310 between after and before exposure EUV310 EUV mA (Mo/ Si ML) Main chain Main chain + protecting Gr Mass number Main chain H 2 C CH 2 CH 3 H 2 C CH Side chain Mw ; 28 Mw ; 42 C 2 H 2 C CH CH 3 H 2 C C Mw ; 44 Mw ; 56 Mw ; 70 Mw ; 86 Mw ; = 151 Sulfonium salt PAG

14 Results (EUV001 vs EUV310) EUV001 EUV mA (Mo/ Si ML) EUV310 EUV mA (Mo/ Si ML) Main chain Solvent + tbu ester Main chain + protecting Gr mass number Mass number n m o H Any Iodonium salt PAG Short summary ; PHS vs Methacryl : PHS << Methacryl Sulfonium salt PAG

15 Results (EUV310 vs EUV311) EUV310 EUV mA (Mo/ Si ML) EUV311 EUV mA (Mo/ Si ML) Main chain Main chain + protecting Gr Mass number Mass number Sulfonium salt PAG Sulfonium salt PAG Short summary ; EUV310 vs EUV311 : Total fragment of 311 is larger than that of EUV310.

16 Results (EUV310 vs EUV312) EUV310 Main chain EUV mA (Mo/ Si ML) EUV312 EUV mA (Mo/ Si ML) Main chain + protecting Gr. Main chain + protecting Gr Mass number Mass number Et H Sulfonium salt PAG Sulfonium salt PAG H Mw ; = 165 Mw ; = 139 Mw ; = 153

17 Summary utgassing from main chain structure The typical partial pressure of PHS and Methacrylate CA resist is the order of 10-6 Pa down to 10-8 Pa. The outgassing species from PHS is smaller those from Methacrylate based resist. utgassing from side chain structure Selection of the protecting group is very important for the low outgassing resist design. Ester ratio Small ester ratio is better for the low outgassing resist design. LER Main chain of Methacryl resist decomposes in EUV irradiation. It due to the tert-carbon bond ratio (De-polymerization). Therefore, LER in Methacryl CA resist is expected to be smaller than that of PHS CA resist.