An ion flux and its kinetic energy spectrum are obtained using a self similar spherically symmetric fluid model of expansion of a collisionless plasma into vacuum.According to the ion flux and energy distribution,the ...An ion flux and its kinetic energy spectrum are obtained using a self similar spherically symmetric fluid model of expansion of a collisionless plasma into vacuum.According to the ion flux and energy distribution,the collector optical lifetime is estimated by knowledge of the sputtering yield of conventional Mo/Si multilayer coatings for the CO_(2)and Nd:YAG pulsed-laser produced plasmas based on the minimum mass tin droplet target without debris mitigation.The results show that the longer wavelength of the CO_(2)laser produced plasma light source is more suitable for extreme ultraviolet lithography than Nd:YAG laser in respect of fast ion debris induced sputtering damage to the collector mirror.展开更多
A grazing incidence flat-field spectrograph using a concave grating was constructed to measure extreme ultraviolet （EUV） emission from a CO 2 laser-produced tin plasma throughout the wavelength region of 5 nm to 20 ...A grazing incidence flat-field spectrograph using a concave grating was constructed to measure extreme ultraviolet （EUV） emission from a CO 2 laser-produced tin plasma throughout the wavelength region of 5 nm to 20 nm for lithography. Spectral efficiency of the EUV emission around 13.5 nm from plate, cavity, and thin foil tin targets was studied. By translating the focusing lens along the laser axis, the dependence of EUV spectra on the amount of defocus was investigated. The results showed that the spectral efficiency was higher for the cavity target in comparison to the plate or foil target, while it decreased with an increase in the defocus distance. The source＇s spectra and the EUV emission intensity normalized to the incident pulse energy at 45 from the target normal were characterized for the in-band （2% of bandwidth） region as a function of laser energy spanning from 46 mJ to 600 mJ for the pure tin plate target. The energy normalized EUV emission was found to increase with the increasing incident pulse energy. It reached the optimum value for the laser energy of around 343 mJ, after which it dropped rapidly.展开更多
The soft X-ray interference lithography(XIL) branch beamline at Shanghai Synchrotron Radiation Facility(SSRF) is briefly introduced in this article. It is designed for obtaining 1D(line/space) and 2D(dot/hole)periodic...The soft X-ray interference lithography(XIL) branch beamline at Shanghai Synchrotron Radiation Facility(SSRF) is briefly introduced in this article. It is designed for obtaining 1D(line/space) and 2D(dot/hole)periodic nanostructures by using two or more coherent extreme ultraviolet(EUV) beams from an undulator source. A transmission-diffraction-grating type of interferometer is used at the end station. Initial results reveal high performance of the beamline, with 50 nm half-pitch 1D and 2D patterns from a single exposure area of400 μm× 400 μm. XIL is used in a growing number of areas, such as EUV resist test, surface enhanced Raman scattering(SERS) and color filter plasmonic devices. By using highly coherent EUV beam, broadband coherent diffractive imaging can be performed on the XIL beamline. Well reconstructed pinhole of φ20 μm has been realized.展开更多
The physical design for a novel low-energy compact-storage-ring-based extreme ultraviolet(EUV)light source was systemically studied.The design process considers the linear and nonlinear beam optics,including transvers...The physical design for a novel low-energy compact-storage-ring-based extreme ultraviolet(EUV)light source was systemically studied.The design process considers the linear and nonlinear beam optics,including transverse matching and the optimization of the dynamic aperture,momentum aperture,and beam lifetime.With a total circumference of 36.7 m and a beam energy of 400 MeV,the storage ring can operate with an average beam current of up to 1 A.With the undulator as the radiator,this facility has the potential to emit EUV radia-tion at 13.5 nm with an average power exceeding 10 W within the bandwidth.In addition,the collective instabili-ties of the lattice at high beam current were analyzed;it was found that the typical instabilities which may occur in an electron storage ring can be reasonably controlled in our design.With the advantages of variable beam energy and current,this design exhibits great promise as a new can-didate for various EUV lithographical applications requir-ing tunable radiation power.展开更多
All-reflective optical systems,due to their material absorption and low refractive index,are used to create the most suitable devices in extreme ultraviolet lithography （EUVL）.In this letter,we present a design for ...All-reflective optical systems,due to their material absorption and low refractive index,are used to create the most suitable devices in extreme ultraviolet lithography （EUVL）.In this letter,we present a design for an all-reflective lithographic projection lens.We also discuss its design idea and structural system.After analysis of the four-mirror optical system,the initial structural parameters are determined,the optical system is optimized,and the tolerances of the system are analyzed.We also show the implementation of optimal layout and desired imaging performance.展开更多
With the development of high-volume manufacturing for very-large-scale integrated circuits,the purity of the light source in the extreme ultraviolet lithography(EUVL)system needs to fulfil extreme requirements in orde...With the development of high-volume manufacturing for very-large-scale integrated circuits,the purity of the light source in the extreme ultraviolet lithography(EUVL)system needs to fulfil extreme requirements in order to avoid thermal effect,optical distortion and critical dimension errors caused by out-of-band radiations.This paper reviews the key technologies and developments of the spectral purity systems for both a free-standing system and a built-in system integrated with the collector.The main challenges and developing trends are also discussed,with a view towards practical applications for further improvement.Designing and manufacturing spectral purity systems for EUVL is not a single task;rather,it requires systematic considerations for all relevant modules.Moreover,the requirement of spectral purity filters drives the innovation in filtering technologies,optical micromachining and advanced metrology.展开更多
作为当前集成电路制造的主流技术,光学光刻在趋近其分辨力极限的同时,面临着越来越大的挑战,即便在波前工程和分辨力增强技术的帮助下,光学光刻的分辨力也难以满足快速发展的半导体产业的技术需求。接近式 X 射线光刻技术(XRL)、散射角...作为当前集成电路制造的主流技术,光学光刻在趋近其分辨力极限的同时,面临着越来越大的挑战,即便在波前工程和分辨力增强技术的帮助下,光学光刻的分辨力也难以满足快速发展的半导体产业的技术需求。接近式 X 射线光刻技术(XRL)、散射角限制电子束投影光刻技术(SCALPEL)、电子束直写光刻技术(EBDW)、极紫外线即软 X 射线投影光刻技术(EUVL)、离子投影光刻技术(IPL)等下一代光刻技术(NGL)将会在特征线宽为 100—70 nm 的技术节点介入集成电路制造的主流技术中。从目前 NGL 技术发展的趋势和市场需求的多元化来看,竞争的结果很可能是各种 NGL 技术并存。当特征尺寸进入纳米尺度(≤100 nm)以后,最终只有那些原子级的成像技术才能成为胜者。展开更多
The swelling of SU-8 mold is one of the most important factors influencing the dimensional accuracy of a metal mieropart produced by ultra-violet lithography galvanik abformung（UV-LIGA）. The isolation belt struc- tu...The swelling of SU-8 mold is one of the most important factors influencing the dimensional accuracy of a metal mieropart produced by ultra-violet lithography galvanik abformung（UV-LIGA）. The isolation belt struc- ture is usually employed to enhance the dimensional accuracy of electroformed metal mieropart. However, noble metal is wasted because the isolation belt is filled with metal when noble metal mieroparts are fabricated. There- fore, a semi-isolation belt structure is presented to save noble metal. Furthermore, a high current density is also introduced to shorten the eleetroforming time, and thus the dimensional accuracy of electroformed gold micropart is improved by using the electrolyte jet. The experimental results indicate that both the semi-isolation belt and the high current density can help to enhance the dimensional accuracy of electroformed gold micropart. Its dimen- sional error is only 5 μm at the current density of 0. 6 A/dm2 while the semi-isolation belt structure is used.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 61078024.
文摘An ion flux and its kinetic energy spectrum are obtained using a self similar spherically symmetric fluid model of expansion of a collisionless plasma into vacuum.According to the ion flux and energy distribution,the collector optical lifetime is estimated by knowledge of the sputtering yield of conventional Mo/Si multilayer coatings for the CO_(2)and Nd:YAG pulsed-laser produced plasmas based on the minimum mass tin droplet target without debris mitigation.The results show that the longer wavelength of the CO_(2)laser produced plasma light source is more suitable for extreme ultraviolet lithography than Nd:YAG laser in respect of fast ion debris induced sputtering damage to the collector mirror.
基金supported by the Scientific Research Foundation of the Education Department of Hubei Province (No.Q20131512)National Natural Science Foundation of China (No.61078024)
文摘A grazing incidence flat-field spectrograph using a concave grating was constructed to measure extreme ultraviolet （EUV） emission from a CO 2 laser-produced tin plasma throughout the wavelength region of 5 nm to 20 nm for lithography. Spectral efficiency of the EUV emission around 13.5 nm from plate, cavity, and thin foil tin targets was studied. By translating the focusing lens along the laser axis, the dependence of EUV spectra on the amount of defocus was investigated. The results showed that the spectral efficiency was higher for the cavity target in comparison to the plate or foil target, while it decreased with an increase in the defocus distance. The source＇s spectra and the EUV emission intensity normalized to the incident pulse energy at 45 from the target normal were characterized for the in-band （2% of bandwidth） region as a function of laser energy spanning from 46 mJ to 600 mJ for the pure tin plate target. The energy normalized EUV emission was found to increase with the increasing incident pulse energy. It reached the optimum value for the laser energy of around 343 mJ, after which it dropped rapidly.
基金Supported by the National Key Basic Research Program of China(No.2012CB825700)the Open Research Project of Large Scientific Facility from Chinese Academy of Sciences:Study on Self-Assembly Technology and Nanometer Array with Ultra-high Density
文摘The soft X-ray interference lithography(XIL) branch beamline at Shanghai Synchrotron Radiation Facility(SSRF) is briefly introduced in this article. It is designed for obtaining 1D(line/space) and 2D(dot/hole)periodic nanostructures by using two or more coherent extreme ultraviolet(EUV) beams from an undulator source. A transmission-diffraction-grating type of interferometer is used at the end station. Initial results reveal high performance of the beamline, with 50 nm half-pitch 1D and 2D patterns from a single exposure area of400 μm× 400 μm. XIL is used in a growing number of areas, such as EUV resist test, surface enhanced Raman scattering(SERS) and color filter plasmonic devices. By using highly coherent EUV beam, broadband coherent diffractive imaging can be performed on the XIL beamline. Well reconstructed pinhole of φ20 μm has been realized.
基金supported by the National Key Research and Development Program of China(No.2016YFA0401901)the National Natural Science Foundation of China(No.11675248).
文摘The physical design for a novel low-energy compact-storage-ring-based extreme ultraviolet(EUV)light source was systemically studied.The design process considers the linear and nonlinear beam optics,including transverse matching and the optimization of the dynamic aperture,momentum aperture,and beam lifetime.With a total circumference of 36.7 m and a beam energy of 400 MeV,the storage ring can operate with an average beam current of up to 1 A.With the undulator as the radiator,this facility has the potential to emit EUV radia-tion at 13.5 nm with an average power exceeding 10 W within the bandwidth.In addition,the collective instabili-ties of the lattice at high beam current were analyzed;it was found that the typical instabilities which may occur in an electron storage ring can be reasonably controlled in our design.With the advantages of variable beam energy and current,this design exhibits great promise as a new can-didate for various EUV lithographical applications requir-ing tunable radiation power.
文摘All-reflective optical systems,due to their material absorption and low refractive index,are used to create the most suitable devices in extreme ultraviolet lithography （EUVL）.In this letter,we present a design for an all-reflective lithographic projection lens.We also discuss its design idea and structural system.After analysis of the four-mirror optical system,the initial structural parameters are determined,the optical system is optimized,and the tolerances of the system are analyzed.We also show the implementation of optimal layout and desired imaging performance.
基金This work was supported by the Science and Technology Commission of Shanghai Municipality(No.22DZ1100300).
文摘With the development of high-volume manufacturing for very-large-scale integrated circuits,the purity of the light source in the extreme ultraviolet lithography(EUVL)system needs to fulfil extreme requirements in order to avoid thermal effect,optical distortion and critical dimension errors caused by out-of-band radiations.This paper reviews the key technologies and developments of the spectral purity systems for both a free-standing system and a built-in system integrated with the collector.The main challenges and developing trends are also discussed,with a view towards practical applications for further improvement.Designing and manufacturing spectral purity systems for EUVL is not a single task;rather,it requires systematic considerations for all relevant modules.Moreover,the requirement of spectral purity filters drives the innovation in filtering technologies,optical micromachining and advanced metrology.
基金Supported by the National Natural Science Foundation of China(91023018)~~
文摘The swelling of SU-8 mold is one of the most important factors influencing the dimensional accuracy of a metal mieropart produced by ultra-violet lithography galvanik abformung（UV-LIGA）. The isolation belt struc- ture is usually employed to enhance the dimensional accuracy of electroformed metal mieropart. However, noble metal is wasted because the isolation belt is filled with metal when noble metal mieroparts are fabricated. There- fore, a semi-isolation belt structure is presented to save noble metal. Furthermore, a high current density is also introduced to shorten the eleetroforming time, and thus the dimensional accuracy of electroformed gold micropart is improved by using the electrolyte jet. The experimental results indicate that both the semi-isolation belt and the high current density can help to enhance the dimensional accuracy of electroformed gold micropart. Its dimen- sional error is only 5 μm at the current density of 0. 6 A/dm2 while the semi-isolation belt structure is used.
