Understanding plasma-material interaction is crucial for achieving steady-state operation of magnetic confinement fusion devices. Kinetic Monte Carlo (kMC) simulation is a powerful tool for investigating the motion of atoms in the plasma facing materials under the influence of this interaction. To predict trapping sites and migration energies necessary for kMC simulations, we developed a deep learning model based on pix2pix for predicting the spatial distribution of binding energy. Results show that the model can reproduce spatial distributions similar to the true values. However, larger errors occur in regions with steep value gradients.
{"title":"Deep learning model for predicting the spatial distribution of binding energy from atomic configurations","authors":"Seiki Saito, Shingo Sato, Hiroaki Nakamura, Chako Takahashi, Keiji Sawada, Kazuo Hoshino, Masahiro Kobayashi, Masahiro Hasuo","doi":"10.35848/1347-4065/ad6e8e","DOIUrl":"https://doi.org/10.35848/1347-4065/ad6e8e","url":null,"abstract":"Understanding plasma-material interaction is crucial for achieving steady-state operation of magnetic confinement fusion devices. Kinetic Monte Carlo (kMC) simulation is a powerful tool for investigating the motion of atoms in the plasma facing materials under the influence of this interaction. To predict trapping sites and migration energies necessary for kMC simulations, we developed a deep learning model based on pix2pix for predicting the spatial distribution of binding energy. Results show that the model can reproduce spatial distributions similar to the true values. However, larger errors occur in regions with steep value gradients.","PeriodicalId":14741,"journal":{"name":"Japanese Journal of Applied Physics","volume":"4 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-04DOI: 10.35848/1347-4065/ad6ed6
Tai-Chen Kuo, Wen-Hsi Lee, Michael Ira Current
In this study, we investigate the effectiveness of high-pressure annealing (HPA) compared to microwave annealing (MWA) in activating n-type and p-type dopants in germanium. For phosphorus dopants, HPA at 500 °C significantly enhances the activation level, resulting in a reduction of sheet resistance to 120.1 ohms sq.−1 and a maximum active concentration of up to 5.76 × 1019 P cm−3. Similarly, for boron dopants, HPA at 800 °C reduces the sheet resistance to 80.6 ohms sq.−1 and achieves a maximum active concentration that maintains effective doping profiles. Transmission electron microscopy images reveal that the amorphous layers implanted with phosphorus and boron are significantly reduced, indicating that HPA is more effective in achieving solid-phase epitaxial regrowth compared to MWA. HPA demonstrates superior performance in minimizing dopant diffusion and reducing sheet resistance for both phosphorus and boron dopants, making it a preferable method for high-temperature annealing in germanium-based devices.
在这项研究中,我们研究了高压退火(HPA)与微波退火(MWA)相比在活化锗中 n 型和 p 型掺杂物方面的效果。对于磷掺杂剂,500 ℃ 下的 HPA 能显著提高活化水平,使薄层电阻降低到 120.1 欧姆 sq.-1,最大活性浓度高达 5.76 × 1019 P cm-3。同样,对于硼掺杂剂,800 ℃ 下的 HPA 可将薄片电阻降低到 80.6 欧姆 sq.-1 并达到最大活性浓度,从而保持有效的掺杂曲线。透射电子显微镜图像显示,植入磷和硼的无定形层明显减少,这表明与 MWA 相比,HPA 能更有效地实现固相外延再生长。对于磷和硼掺杂剂,HPA 在最大限度地减少掺杂剂扩散和降低薄片电阻方面都表现出了卓越的性能,使其成为锗基器件高温退火的首选方法。
{"title":"Investigation of the activation and diffusion of ion-implanted p-type and n-type dopants in germanium using high-pressure annealing","authors":"Tai-Chen Kuo, Wen-Hsi Lee, Michael Ira Current","doi":"10.35848/1347-4065/ad6ed6","DOIUrl":"https://doi.org/10.35848/1347-4065/ad6ed6","url":null,"abstract":"In this study, we investigate the effectiveness of high-pressure annealing (HPA) compared to microwave annealing (MWA) in activating n-type and p-type dopants in germanium. For phosphorus dopants, HPA at 500 °C significantly enhances the activation level, resulting in a reduction of sheet resistance to 120.1 ohms sq.<sup>−1</sup> and a maximum active concentration of up to 5.76 × 10<sup>19</sup> P cm<sup>−3</sup>. Similarly, for boron dopants, HPA at 800 °C reduces the sheet resistance to 80.6 ohms sq.<sup>−1</sup> and achieves a maximum active concentration that maintains effective doping profiles. Transmission electron microscopy images reveal that the amorphous layers implanted with phosphorus and boron are significantly reduced, indicating that HPA is more effective in achieving solid-phase epitaxial regrowth compared to MWA. HPA demonstrates superior performance in minimizing dopant diffusion and reducing sheet resistance for both phosphorus and boron dopants, making it a preferable method for high-temperature annealing in germanium-based devices.","PeriodicalId":14741,"journal":{"name":"Japanese Journal of Applied Physics","volume":"10 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-04DOI: 10.35848/1347-4065/ad6e90
Andrey Ushakov, Ad Verlaan, Ulf Stephan, Olaff Steinke, Cederik Meekes, André Rijfers, Peter Giesen, Eiichi Yatsuka, Maarten de Bock, Michele Bassan, Lucas Moser, Masahito Yokoyama, Erik van Beekum, Shobhit Yadav
New plasma sources are proposed to clean optical mirrors in diagnostic instruments of the ITER experiment considering RF discharges operating at low pressures (1–10 Pa) in inert gases. There are nearly twenty optical diagnostics where the front-end optical mirrors may require plasma cleaning. The mirrors vary in size and would need up to 400 W in the discharge to form ion fluxes capable of removing Be- and W-containing contaminants to restore the optical performance with tolerable damage to the mirror. The plasma sources suggested to clean contaminants include a vacuum matching circuit placed close to the mirror and a quarter wavelength band stop notch filter when mirror water cooling is needed. Long-term operation stability and cleaning homogeneity may employ a driving frequency variation to tune the circuit and a phase shift for RF voltages to clean two mirrors simultaneously. In this paper, the plasma sources based on 40 MHz RF discharge to clean first mirrors are studied experimentally for two ITER optical instruments: the Edge Thomson Scattering and the Visible Spectroscopy Reference System. Frequency tuning and phase shifting are studied in realistic configurations prototyping diagnostic port plug geometries.
考虑到在惰性气体中以低压(1-10 帕)运行的射频放电,建议采用新的等离子源来清洁热核实验堆实验诊断仪器中的光学镜。有近二十种光学诊断仪器的前端光学镜可能需要等离子清洗。这些反射镜的尺寸各不相同,需要高达 400 W 的放电功率才能形成能够清除含 Be 和 W 污染物的离子通量,从而在对反射镜造成可容忍损坏的情况下恢复光学性能。建议用于清洁污染物的等离子源包括一个靠近反射镜的真空匹配电路,以及一个四分之一波长的带阻带陷波滤波器(当需要对反射镜进行水冷时)。长期运行的稳定性和清洁的均匀性可以利用驱动频率的变化来调整电路,并利用射频电压的相移来同时清洁两个反射镜。本文针对两个热核实验堆光学仪器:边缘汤姆逊散射和可见光谱参考系统,对基于 40 MHz 射频放电的等离子源进行了实验研究,以清洁第一面反射镜。在诊断端口插头几何原型的实际配置中对频率调整和相移进行了研究。
{"title":"Plasma sources sputtering nanoscale contaminants with low-energy ion flux on front-end mirrors in ITER optical diagnostics","authors":"Andrey Ushakov, Ad Verlaan, Ulf Stephan, Olaff Steinke, Cederik Meekes, André Rijfers, Peter Giesen, Eiichi Yatsuka, Maarten de Bock, Michele Bassan, Lucas Moser, Masahito Yokoyama, Erik van Beekum, Shobhit Yadav","doi":"10.35848/1347-4065/ad6e90","DOIUrl":"https://doi.org/10.35848/1347-4065/ad6e90","url":null,"abstract":"New plasma sources are proposed to clean optical mirrors in diagnostic instruments of the ITER experiment considering RF discharges operating at low pressures (1–10 Pa) in inert gases. There are nearly twenty optical diagnostics where the front-end optical mirrors may require plasma cleaning. The mirrors vary in size and would need up to 400 W in the discharge to form ion fluxes capable of removing Be- and W-containing contaminants to restore the optical performance with tolerable damage to the mirror. The plasma sources suggested to clean contaminants include a vacuum matching circuit placed close to the mirror and a quarter wavelength band stop notch filter when mirror water cooling is needed. Long-term operation stability and cleaning homogeneity may employ a driving frequency variation to tune the circuit and a phase shift for RF voltages to clean two mirrors simultaneously. In this paper, the plasma sources based on 40 MHz RF discharge to clean first mirrors are studied experimentally for two ITER optical instruments: the Edge Thomson Scattering and the Visible Spectroscopy Reference System. Frequency tuning and phase shifting are studied in realistic configurations prototyping diagnostic port plug geometries.","PeriodicalId":14741,"journal":{"name":"Japanese Journal of Applied Physics","volume":"23 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-04DOI: 10.35848/1347-4065/ad6f86
Jiahao Wang, Takahiro Kozawa
In the lithography used for the high-volume production of semiconductor devices, the photoresist film becomes thin with the reduction in pattern size to prevent the pattern collapse due to the surface tension of rinsing liquids. The interfacial effect becomes strong with the reduction in photoresist film thickness. In the development process, it is of importance to clarify the relationship between the photoresist and the underlayer for fine patterning. In this study, the dissolution kinetics of poly(4-hydroxystyrene) (PHS) partially protected by t-butoxycarbonyl (t-Boc) groups in tetramethylammonium hydroxide (TMAH) aqueous solution was found to be related to the surface free energy of the underlayer. The attenuation rate of developer viscosity first decreased and then increased with the polar-to-dispersion component ratio. An inflection point with the lowest rate existed. The TMAH concentration affected not only the attenuation rate but also the ratio of polar to dispersion components at the minimum attenuation rate.
{"title":"Relationship between the surface free energy of underlayers and the dissolution kinetics of poly(4-hydroxystyrene) partially protected by t-butoxycarbonyl groups in tetramethylammonium hydroxide aqueous developer","authors":"Jiahao Wang, Takahiro Kozawa","doi":"10.35848/1347-4065/ad6f86","DOIUrl":"https://doi.org/10.35848/1347-4065/ad6f86","url":null,"abstract":"In the lithography used for the high-volume production of semiconductor devices, the photoresist film becomes thin with the reduction in pattern size to prevent the pattern collapse due to the surface tension of rinsing liquids. The interfacial effect becomes strong with the reduction in photoresist film thickness. In the development process, it is of importance to clarify the relationship between the photoresist and the underlayer for fine patterning. In this study, the dissolution kinetics of poly(4-hydroxystyrene) (PHS) partially protected by <italic toggle=\"yes\">t</italic>-butoxycarbonyl (<italic toggle=\"yes\">t</italic>-Boc) groups in tetramethylammonium hydroxide (TMAH) aqueous solution was found to be related to the surface free energy of the underlayer. The attenuation rate of developer viscosity first decreased and then increased with the polar-to-dispersion component ratio. An inflection point with the lowest rate existed. The TMAH concentration affected not only the attenuation rate but also the ratio of polar to dispersion components at the minimum attenuation rate.","PeriodicalId":14741,"journal":{"name":"Japanese Journal of Applied Physics","volume":"303 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-03DOI: 10.35848/1347-4065/ad6f84
Tomohiro Shiozaki, Ariasu Tamura, Yosuke Mizuno
We investigate a simple structure in which a polarization-maintaining fiber (PMF) is sandwiched between two single-mode fibers (SMFs). By injecting broadband light and observing the modal interference spectrum of the transmitted light in the 870 nm range, we identify a clear shift dependent on the strain applied to the PMF. In addition, we demonstrate that in the same wavelength range, the strain applied to the SMFs before and after the PMF does not influence the interference spectrum. This result confirms that only the PMF segment exhibits strain sensitivity.
{"title":"Strain sensing based on modal interference spectrum in polarization-maintaining fiber","authors":"Tomohiro Shiozaki, Ariasu Tamura, Yosuke Mizuno","doi":"10.35848/1347-4065/ad6f84","DOIUrl":"https://doi.org/10.35848/1347-4065/ad6f84","url":null,"abstract":"We investigate a simple structure in which a polarization-maintaining fiber (PMF) is sandwiched between two single-mode fibers (SMFs). By injecting broadband light and observing the modal interference spectrum of the transmitted light in the 870 nm range, we identify a clear shift dependent on the strain applied to the PMF. In addition, we demonstrate that in the same wavelength range, the strain applied to the SMFs before and after the PMF does not influence the interference spectrum. This result confirms that only the PMF segment exhibits strain sensitivity.","PeriodicalId":14741,"journal":{"name":"Japanese Journal of Applied Physics","volume":"23 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hot carrier instability (HCI) in a floating body cell (FBC) has been investigated. The FBC is a dynamic random-access memory (DRAM) made entirely of a silicon-on-insulator (SOI)-MOS without a capacitor. For FBC realization, there is an influence of a physical phenomenon different from the normal MOS because of its structural and operational characteristics of SOI-MOS. The difference between bulk and SOI-MOS is not yet clear, especially for HCI. In this study, we clarified the importance of the structural and geometrical factors of the FBC cell transistor and the SOI-specific floating body effect in the HCI regime of FBCs.
对浮动体单元(FBC)中的热载流子不稳定性(HCI)进行了研究。FBC 是一种动态随机存取存储器(DRAM),完全由无电容的硅绝缘体(SOI)-MOS 制成。由于 SOI-MOS 的结构和工作特性,在实现 FBC 时会受到不同于普通 MOS 的物理现象的影响。体MOS和SOI-MOS之间的区别尚不明确,特别是在人机交互方面。在这项研究中,我们阐明了 FBC 单元晶体管的结构和几何因素以及 SOI 特定浮体效应在 FBC 的 HCI 机制中的重要性。
{"title":"Analysis of hot carrier instability in a floating body cell","authors":"Hiroomi Nakajima, Tomoaki Shino, Hironobu Furuhashi, Jun Nishimura, Tomoki Higashi, Katsuyuki Fujita, Kosuke Hatsuda, Ryo Fukuda, Takeshi Kajiyama","doi":"10.35848/1347-4065/ad69eb","DOIUrl":"https://doi.org/10.35848/1347-4065/ad69eb","url":null,"abstract":"Hot carrier instability (HCI) in a floating body cell (FBC) has been investigated. The FBC is a dynamic random-access memory (DRAM) made entirely of a silicon-on-insulator (SOI)-MOS without a capacitor. For FBC realization, there is an influence of a physical phenomenon different from the normal MOS because of its structural and operational characteristics of SOI-MOS. The difference between bulk and SOI-MOS is not yet clear, especially for HCI. In this study, we clarified the importance of the structural and geometrical factors of the FBC cell transistor and the SOI-specific floating body effect in the HCI regime of FBCs.","PeriodicalId":14741,"journal":{"name":"Japanese Journal of Applied Physics","volume":"37 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142218111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}