{"title":"Spatially-resolved spectroscopic investigation of the inhomogeneous magnetic field effects on a low-pressure capacitively-coupled nitrogen plasma","authors":"","doi":"10.1016/j.cap.2024.09.010","DOIUrl":null,"url":null,"abstract":"<div><div>Although magnetized plasmas have been frequently used to enhance the process rate or improve the film quality via the control of ion flux as well as energy and plasma density in semiconductor processes, the inhomogeneous magnetic field—which leads to plasma non-uniformity—remains as a problem to be solved. To address this problem, it is essential to conduct a comprehensive assessment of the magnetic effect throughout the entire discharge. Therefore, in the present study, we investigated the magnetic field effects (B < 100 G) on a capacitively-coupled nitrogen plasma based on spectroscopic analyses. The spatially-resolved emission spectra were measured along the radial direction at various vertical positions under the pressures of 10 mTorr and 250 mTorr both with and without magnetic field. By analyzing emission spectra such as N<sub>2</sub> FPS, N<sub>2</sub> SPS, N<sub>2</sub><sup>+</sup> FNS, and N I, we were able to obtain the radial distributions of reactive species density, vibrational temperature, and excitation temperature. In low-pressure plasma, with the application of a magnetic field, maximum increases in vibrational temperature and excitation temperature of 462 K and 491 K, respectively, were observed within the bulk region beneath the magnet. This magnetic effect resulted in a significant increase in reactive species density along the radial direction. It was also found that the local enhancement of ion density by magnetic field was strongly related to the increase in excitation temperature and the density of the N<sub>2</sub><sup>+</sup>(B) state. From this result, it is suggested that introducing an asymmetric magnetic field could modulate the spatial distributions of the physical and chemical properties of the plasma.</div></div>","PeriodicalId":11037,"journal":{"name":"Current Applied Physics","volume":null,"pages":null},"PeriodicalIF":2.4000,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Current Applied Physics","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1567173924002104","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Although magnetized plasmas have been frequently used to enhance the process rate or improve the film quality via the control of ion flux as well as energy and plasma density in semiconductor processes, the inhomogeneous magnetic field—which leads to plasma non-uniformity—remains as a problem to be solved. To address this problem, it is essential to conduct a comprehensive assessment of the magnetic effect throughout the entire discharge. Therefore, in the present study, we investigated the magnetic field effects (B < 100 G) on a capacitively-coupled nitrogen plasma based on spectroscopic analyses. The spatially-resolved emission spectra were measured along the radial direction at various vertical positions under the pressures of 10 mTorr and 250 mTorr both with and without magnetic field. By analyzing emission spectra such as N2 FPS, N2 SPS, N2+ FNS, and N I, we were able to obtain the radial distributions of reactive species density, vibrational temperature, and excitation temperature. In low-pressure plasma, with the application of a magnetic field, maximum increases in vibrational temperature and excitation temperature of 462 K and 491 K, respectively, were observed within the bulk region beneath the magnet. This magnetic effect resulted in a significant increase in reactive species density along the radial direction. It was also found that the local enhancement of ion density by magnetic field was strongly related to the increase in excitation temperature and the density of the N2+(B) state. From this result, it is suggested that introducing an asymmetric magnetic field could modulate the spatial distributions of the physical and chemical properties of the plasma.
期刊介绍:
Current Applied Physics (Curr. Appl. Phys.) is a monthly published international journal covering all the fields of applied science investigating the physics of the advanced materials for future applications.
Other areas covered: Experimental and theoretical aspects of advanced materials and devices dealing with synthesis or structural chemistry, physical and electronic properties, photonics, engineering applications, and uniquely pertinent measurement or analytical techniques.
Current Applied Physics, published since 2001, covers physics, chemistry and materials science, including bio-materials, with their engineering aspects. It is a truly interdisciplinary journal opening a forum for scientists of all related fields, a unique point of the journal discriminating it from other worldwide and/or Pacific Rim applied physics journals.
Regular research papers, letters and review articles with contents meeting the scope of the journal will be considered for publication after peer review.
The Journal is owned by the Korean Physical Society.