The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform

Seiichi Tagawa - One of the best experts on this subject based on the ideXlab platform.

  • removal of ion implanted Photoresists using atomic hydrogen
    Journal of The Electrochemical Society, 2010
    Co-Authors: Masashi Yamamoto, Hideo Horibe, Yousuke Goto, Takeshi Maruoka, Eiji Kusano, Akihiko Kono, Muneaki Sakamoto, Hirofumi Seki, Seiichi Tagawa
    Abstract:

    In this paper, we investigated the removal characteristic of positive-tone novolak Photoresists into which B, P, and As ions were implanted with doses of 5 × 10 12 -5 × 10 15 atoms/cm 2 at an acceleration energy of 70 keV using atomic hydrogen, and the hardening mechanisms for the Photoresists. All of the ion-implanted Photoresists with doses up to 5 × 10 15 atoms/cm 2 were removed without regard for ion species. The removal rates of the Photoresists decreased with increasing ion-implantation dose due to hardening of the photoresist surfaces with implantation. The thickness of the surface-hardened layer of the Photoresists decreased in the order of B → P → As, and the removal rate increased with decreasing thickness. The energy supplied from the ions to the photoresist concentrated on the surface side in the order of B → P → As, and the impact of the heavier ion on the photoresist was greater than that of the lighter ion. We deduced that the Photoresists exhibited carbonization and cross-linkage attributable to the decrease in OH, CH, and 0 1s and the increase in C=C, C 1s, and π-conjugated systems.

  • Removal of Ion-Implanted Photoresists Using Wet Ozone
    Journal of The Electrochemical Society, 2009
    Co-Authors: Masashi Yamamoto, Hideo Horibe, Yousuke Goto, Takeshi Maruoka, Miura Toshinori, Eiji Kusano, Seiichi Tagawa
    Abstract:

    Using environmentally friendly wet ozone instead of chemicals, we removed B-, P-, and As-ion-implanted positive-tone novolak Photoresists with an implantation dose of 5 × 10 12 ―1 × 10 16 atoms/cm 2 at an acceleration energy of 70 keV. Ion-implanted Photoresists with an implantation dose exceeding 5 × 10 15 atoms/cm 2 could not be removed, but Photoresists implanted at doses below 5 × 10 13 atoms/cm 2 could be removed. Photoresist implanted with B ions at 5 × 10 14 atoms/cm 2 was removed slowly, but Photoresists implanted with P and As ions were not removed at all. The hardness of the photoresist with B ions implanted at 5 × 10 14 atoms/cm 2 was 1.8 times greater than that of the nonimplanted photoresist (AZ6112), that of the P-ion-implanted photoresist was eight times greater, and that of the As-ion-implanted photoresist was five times greater. The B-ion-implanted photoresist was softer than the P- and As-ion-implanted Photoresists. We also obtained the calculation results in which the energy supplied from the B ions to the photoresist was lower than that from P and As ions. We assumed that the ion-implanted Photoresists were hardened by cross-linkage due to the energies supplied to the Photoresists from the ions. Therefore, we determined that the hardness threshold of the photoresist that could be removed by using wet ozone was twice the hardness of AZ6112.

James W. Thackeray - One of the best experts on this subject based on the ideXlab platform.

  • Backbone Degradable Poly(aryl acetal) Photoresist Polymers: Synthesis, Acid Sensitivity, and Extreme Ultraviolet Lithography Performance
    Macromolecules, 2019
    Co-Authors: Matthias S. Ober, Duane R. Romer, John B. Etienne, P. J. Thomas, Vipul Jain, James F. Cameron, James W. Thackeray
    Abstract:

    A new class of acid labile poly(aryl acetal) polymers has been developed that can be used in photoresist formulations for next-generation microlithography techniques including extreme ultraviolet (EUV) or electron beam lithography. Example polymers have been synthesized by an optimized Suzuki polycondensation protocol. They are soluble in common photoresist solvents but are insoluble in water or aqueous bases that are used to develop positive Photoresists. The structural design includes further elements that are aimed at improving photoresist resolution, stability, and etch resistance. Upon acid exposure, the acetal linkages are cleaved, and the polymers degrade into phenolic terphenyl fragments, which are readily soluble in a photoresist developer. Polymer degradation has been studied by NMR and LC-MS. Lithographic formulations have been developed and tested in line-and-space patterning experiments using EUV photolithography. Optimized resist formulations achieved 22 nm resolution with line width roughne...

  • Backbone Degradable Poly(aryl acetal) Photoresist Polymers: Synthesis, Acid Sensitivity, and Extreme Ultraviolet Lithography Performance
    2019
    Co-Authors: Matthias S. Ober, Duane R. Romer, P. J. Thomas, Vipul Jain, James F. Cameron, John Etienne, James W. Thackeray
    Abstract:

    A new class of acid labile poly­(aryl acetal) polymers has been developed that can be used in photoresist formulations for next-generation microlithography techniques including extreme ultraviolet (EUV) or electron beam lithography. Example polymers have been synthesized by an optimized Suzuki polycondensation protocol. They are soluble in common photoresist solvents but are insoluble in water or aqueous bases that are used to develop positive Photoresists. The structural design includes further elements that are aimed at improving photoresist resolution, stability, and etch resistance. Upon acid exposure, the acetal linkages are cleaved, and the polymers degrade into phenolic terphenyl fragments, which are readily soluble in a photoresist developer. Polymer degradation has been studied by NMR and LC-MS. Lithographic formulations have been developed and tested in line-and-space patterning experiments using EUV photolithography. Optimized resist formulations achieved 22 nm resolution with line width roughness values of 5.7 nm

Masashi Yamamoto - One of the best experts on this subject based on the ideXlab platform.

  • Oxygen additive effects on decomposition rate of poly(vinyl phenol)-based polymers using hydrogen radicals produced by a tungsten hot-wire catalyst
    Thin Solid Films, 2019
    Co-Authors: Masashi Yamamoto, Shiro Nagaoka, Keisuke Ohdaira, Hironobu Umemoto, Hideo Horibe
    Abstract:

    Abstract For fabricating semiconductor devices and for microelectromechanical systems, Photoresists are important materials supporting photolithography processes. However, Photoresists must be removed for subsequent processes. An earlier study demonstrated that adding a small amount of oxygen gas to the atmosphere in which hydrogen radicals are produced increased the decomposition rate of a positive-tone novolac photoresist. For this study, we prepared polymers with different side chain structures based on poly(vinyl phenol) (PVP). We examined the effects of added oxygen and the oxygen-added hydrogen radicals on the decomposition rates of PVP-based polymers. Hydroxyl groups of PVP are partly substituted with tert-butoxycarbonyl groups in order to use for base polymer of KrF photoresist. Results show that oxygen addition can be useful for KrF photoresist removal.

  • removal of ion implanted Photoresists using atomic hydrogen
    Journal of The Electrochemical Society, 2010
    Co-Authors: Masashi Yamamoto, Hideo Horibe, Yousuke Goto, Takeshi Maruoka, Eiji Kusano, Akihiko Kono, Muneaki Sakamoto, Hirofumi Seki, Seiichi Tagawa
    Abstract:

    In this paper, we investigated the removal characteristic of positive-tone novolak Photoresists into which B, P, and As ions were implanted with doses of 5 × 10 12 -5 × 10 15 atoms/cm 2 at an acceleration energy of 70 keV using atomic hydrogen, and the hardening mechanisms for the Photoresists. All of the ion-implanted Photoresists with doses up to 5 × 10 15 atoms/cm 2 were removed without regard for ion species. The removal rates of the Photoresists decreased with increasing ion-implantation dose due to hardening of the photoresist surfaces with implantation. The thickness of the surface-hardened layer of the Photoresists decreased in the order of B → P → As, and the removal rate increased with decreasing thickness. The energy supplied from the ions to the photoresist concentrated on the surface side in the order of B → P → As, and the impact of the heavier ion on the photoresist was greater than that of the lighter ion. We deduced that the Photoresists exhibited carbonization and cross-linkage attributable to the decrease in OH, CH, and 0 1s and the increase in C=C, C 1s, and π-conjugated systems.

  • Removal of Ion-Implanted Photoresists Using Wet Ozone
    Journal of The Electrochemical Society, 2009
    Co-Authors: Masashi Yamamoto, Hideo Horibe, Yousuke Goto, Takeshi Maruoka, Miura Toshinori, Eiji Kusano, Seiichi Tagawa
    Abstract:

    Using environmentally friendly wet ozone instead of chemicals, we removed B-, P-, and As-ion-implanted positive-tone novolak Photoresists with an implantation dose of 5 × 10 12 ―1 × 10 16 atoms/cm 2 at an acceleration energy of 70 keV. Ion-implanted Photoresists with an implantation dose exceeding 5 × 10 15 atoms/cm 2 could not be removed, but Photoresists implanted at doses below 5 × 10 13 atoms/cm 2 could be removed. Photoresist implanted with B ions at 5 × 10 14 atoms/cm 2 was removed slowly, but Photoresists implanted with P and As ions were not removed at all. The hardness of the photoresist with B ions implanted at 5 × 10 14 atoms/cm 2 was 1.8 times greater than that of the nonimplanted photoresist (AZ6112), that of the P-ion-implanted photoresist was eight times greater, and that of the As-ion-implanted photoresist was five times greater. The B-ion-implanted photoresist was softer than the P- and As-ion-implanted Photoresists. We also obtained the calculation results in which the energy supplied from the B ions to the photoresist was lower than that from P and As ions. We assumed that the ion-implanted Photoresists were hardened by cross-linkage due to the energies supplied to the Photoresists from the ions. Therefore, we determined that the hardness threshold of the photoresist that could be removed by using wet ozone was twice the hardness of AZ6112.

Matthias S. Ober - One of the best experts on this subject based on the ideXlab platform.

  • Backbone Degradable Poly(aryl acetal) Photoresist Polymers: Synthesis, Acid Sensitivity, and Extreme Ultraviolet Lithography Performance
    Macromolecules, 2019
    Co-Authors: Matthias S. Ober, Duane R. Romer, John B. Etienne, P. J. Thomas, Vipul Jain, James F. Cameron, James W. Thackeray
    Abstract:

    A new class of acid labile poly(aryl acetal) polymers has been developed that can be used in photoresist formulations for next-generation microlithography techniques including extreme ultraviolet (EUV) or electron beam lithography. Example polymers have been synthesized by an optimized Suzuki polycondensation protocol. They are soluble in common photoresist solvents but are insoluble in water or aqueous bases that are used to develop positive Photoresists. The structural design includes further elements that are aimed at improving photoresist resolution, stability, and etch resistance. Upon acid exposure, the acetal linkages are cleaved, and the polymers degrade into phenolic terphenyl fragments, which are readily soluble in a photoresist developer. Polymer degradation has been studied by NMR and LC-MS. Lithographic formulations have been developed and tested in line-and-space patterning experiments using EUV photolithography. Optimized resist formulations achieved 22 nm resolution with line width roughne...

  • Backbone Degradable Poly(aryl acetal) Photoresist Polymers: Synthesis, Acid Sensitivity, and Extreme Ultraviolet Lithography Performance
    2019
    Co-Authors: Matthias S. Ober, Duane R. Romer, P. J. Thomas, Vipul Jain, James F. Cameron, John Etienne, James W. Thackeray
    Abstract:

    A new class of acid labile poly­(aryl acetal) polymers has been developed that can be used in photoresist formulations for next-generation microlithography techniques including extreme ultraviolet (EUV) or electron beam lithography. Example polymers have been synthesized by an optimized Suzuki polycondensation protocol. They are soluble in common photoresist solvents but are insoluble in water or aqueous bases that are used to develop positive Photoresists. The structural design includes further elements that are aimed at improving photoresist resolution, stability, and etch resistance. Upon acid exposure, the acetal linkages are cleaved, and the polymers degrade into phenolic terphenyl fragments, which are readily soluble in a photoresist developer. Polymer degradation has been studied by NMR and LC-MS. Lithographic formulations have been developed and tested in line-and-space patterning experiments using EUV photolithography. Optimized resist formulations achieved 22 nm resolution with line width roughness values of 5.7 nm

S. V. Eswaran - One of the best experts on this subject based on the ideXlab platform.

  • Novolak resins: structure elucidation by multidimensional NMR techniques and correlation with lithographic performance
    Polymer International, 2003
    Co-Authors: Debmalya Roy, P. K. Basu, P. Raghunathan, S. V. Eswaran
    Abstract:

    Photo-active chemicals blended with novolak resins, solvents and certain other additives serve as Photoresists and are the real workhorses of the burgeoning microlithography industry, which plays a key role in making electronic circuits for ICs and VLSIs at micron and sub-micron levels. It has been realized over the years that the microstructure of these matrix polymers (novolak resins) is very crucial for better lithographic performance. Although various analytical techniques exist for characterizing novolak resins, precise and unambiguous structural details are obtained only through NMR experiments. In this paper, we review the applications of a range of NMR experimental techniques to the structure elucidation of novolak polymers and co-polymers. Such information is seen to lead to the design of high-performance Photoresists. The optimum percentage of the different phenolic units in novolak resins, which is very crucial for lithographic performance, can also be determined using these spectroscopic techniques. Using DEPT and INEPT 13C NMR spectra of novolak resins, two formulae have been developed for quantitative estimation of the lithographic performance of Photoresists. On the basis of a comparison of the NMR spectra of a photoresist before and after photolysis, the mechanism of action of a photoresist can be probed, and this should lead to a deeper insight into the design of high-performing Photoresists. Copyright © 2003 Society of Chemical Industry