Time Resolved Spectroscopy of Nanoparticle EUV Photoresists Reactions of HfO nanoparticles with electrons and the following solubility change studied by pulse radiolysis Seiichi Tagawa, Satoshi Enomoto, Akihiro Oshima The Institute of Scientific and Industrial Research, Osaka University 8 1 Mihogaoka, Ibaraki, Osaka 567 0047, Japan tagawa@sanken.osaka u.ac.jp
Nanosecond Pulse Radiolysis System
Results Pulse radiolysis studies on solvated electrons in methanol CH 3 OH CH 3 OH.+ + e s - CH 3 OH CH 3 OH.+. + CH 2 OH + CH 3 OH 2 + Additive + + e s - e s - PAG HfO nanoparticle(hfo2ma4) Products )k HfO nanoparticle(hfo2ma 4 ) was given by Chris Ober. CH 3 OH 2 + Neutral Products 0.30.20.100 ns 100 ns 2040608010120avelength(nmFig. Transient absorption spectra of solvated electrons obtained by the pulse radiolysis of neat methanol.0250 nsw140
The rate constant of acid generators with solvated electrons in methanol Optical Density 0.5 0.4 0.3 0.2 0mM 0.1 0.5mM 0.1mM 2mM 0.0 0 100 200 300 400 500 Time (ns) Fig. Time dependent behavior of solvated electrons obtained by the pulse radiolysis of diphenyliodonium triflate solutions in methanol, monitored at 650 nm. Ionic Acid Generator DPI-CF 3 SO 3 TPS-CF 3 SO 3 TPS-SbF 6 CMS-CF 3 SO 3 NAT-CF 3 SO 3 Non-ionic Acid Generator TAZ TAZ 2 DNB DS Base Polymer m-cresol novolac 2.4 10 10 M -1 s -1 2.7 10 10 M -1 s -1 2.5 10 10 M -1 s -1 1.6 10 10 M -1 s -1 1.9 10 10 M -1 s -1 2.2 10 10 M -1 s -1 2.5 10 10 M -1 s -1 2.2 10 10 M -1 s -1 1.1 10 10 M -1 s -1 10 7 ~10 8 basem -1 s -1 / in methanol solution
HfO nanoparticle(hfo2ma 4 ) pulse radiolysis Spectra [Condition] Concentration:Left figure:meoh Right figure:2.5mm Hf nano particle in MeOH Ar Bubbling (10min.) Wavelength 350nm-800nm [O.D.] MeOH MeOH 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 350 400 450 500 550 600 650 700 750 800 λ[nm] 65ns 100ns 200ns 300ns [O.D.] 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 2.5mM Hf nano particle in MeOH 68.5ns 100ns 200ns 300ns 0 340 390 440 490 540 590 640 690 740 790 λ[nm]
Hf nano particle pulse radiolysis result @ 640nm [Condition] Concentration:Left figure:meoh Right figure:2.5mm Hf nano particle in MeOH Ar Bubbling (10min.) Wavelength 640nm Hf nano particle in MeOH e + Hf nano particle Hf nano particle [O.D.] 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 MeOH 0 100 200 300 400 t[ns] [O.D.] 2.5mM Hf nano particle in MeOH 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 50 100 150 200 250 300 350 400 λ[nm]
Hf nano particle pulse radiolysis result @ 1340nm [Condition] Concentration:Left figure:ch 3 CN Right figure:2.5mm Hf nano particle in CH 3 CN Ar Bubbling (10min.) Wavelength 1340nm Hf nano particle in CH 3 CN (e, CH 3 CN, (CH 3 CN) 2 ) + Hf nano particle Hf nano particle 0.6 0.5 2.5mM Hf nano particle @1340nm 0.06 0.05 [O.D.] 0.4 0.3 0.2 0.1 0-0.1 0 100 200 300 t[ns] CH3CN 2.5mM k[ns-1] 0.04 0.03 0.02 k=1.4 10 10 [M -1 s -1 ] 0.01 0 0 0.0005 0.001 0.0015 0.002 0.0025 0.003 c[m] Example TPS-Tf in CH3CN ; 6.3 10 10 [M -1 s -1 ]
Pulse Radiolysis Results HfO nanoparticles react with solvated electrons in CH 3 OH and CH 3 CN very effectively. The rate constant of HfO nanoparticles with solvated electrons in CH 3 CN is 1.4 x 10 10 M 1 s 1. During pulse irradiation of HfO nanoparticles in THF and CH3CN, aggregation occurs.
Dynamic light scattering measurements of HfO aggregated particle produced in irradiated solutions
Dynamic light scattering measurement of HfO aggregated particle Zetasizer Measurement conditions Room temperature 24 C 1.2 1.2cm 2 crystal cell Cell Length 10mm Malvern Instruments Nano ZS ZEN3600
Dynamic light scattering Using Zetasizer (Sysmecs) Peak 1 Peak 2 HfO in 5mM acetonitrile after pulsed electron irradiation Radius (nm)
Aggregated HfO nanoparticle after pulsed EB irradiation (pulse radiolysis measurement) were observed by dynamic light scattering method (Zetasizaer: Sysmecs) However, in the case of irradiated THF solution, we could not measured because the aggregated particles was precipitating. On the other hand, for acetonitrile solution, although a low concentrated one (5mM HfO) was measured, high concentrated one (20mM HfO) could not be measured. SEM measurements of HfO aggregated particle produced in irradiated solutions were carried out. Sample preparation of observation HfO solution was spin coated the Si wafer. Spin condition: 2500rpm 30s. After spin coating and SEM measurement was carried out.
Irrad. 5mM in Acetonitrile SEM Irrad. 20mM in Acetonitrile
Non irrad. 5mM in THF Irrad. 5mM in THF Irrad. 25mM in THF
Results of Particles Size Measurement Size of aggregated HfO nano particle after pulsed EB irradiation were evaluated. In irradiated THF solution, particle size showed about 300nm 450nm (Rough value). In irradiated acetonitrile solution, particle size showed about 100nm 500nm. Particle size increased with concentration.
Conclusion HfO nanoparticles react with solvated electrons in CH 3 OH and CH 3 CN very effectively. The rate constant of HfO nanoparticles with solvated electrons in CH 3 CN is 1.4 x 10 10 M 1 s 1. During pulse irradiation of HfO nanoparticles in THF and CH 3 CN, aggregation occurs. Dynamic light scattering and SEM measurements of HfO aggregated particle produced in irradiated solutions