Phase composition of sputter deposited tungsten thin films

IF 5.3 2区 材料科学 Q1 MATERIALS SCIENCE, COATINGS & FILMS
{"title":"Phase composition of sputter deposited tungsten thin films","authors":"","doi":"10.1016/j.surfcoat.2024.131447","DOIUrl":null,"url":null,"abstract":"<div><div>Sputter deposited tungsten thin films are studied by X-ray diffraction. Two phases can be identified: <span><math><mi>α</mi></math></span>-W and <span><math><mi>β</mi></math></span>-W based on the observed (110), and (200) and (210) Bragg reflections, respectively. With increasing film thickness (50 to 200 nm), the phase composition shifts from <span><math><mi>β</mi></math></span>-W towards <span><math><mi>α</mi></math></span>-W. No influence of the base pressure (3 × 10<sup>−3</sup>–3 × 10<sup>−5</sup> Pa) on the phase composition is observed. Also the influence of the argon pressure (0.3 to 0.7 Pa) is rather weak. The strongest shift towards <span><math><mi>α</mi></math></span>-W composed thin films is obtained by increasing the discharge power (50 to 250 W). This trend is further studied by energy flux measurements using a calorimetric probe. These measurements rule out a strong change of the substrate temperature, and an impact of the energy flux scaled by the deposition rate (total energy per deposited atom). Test particle Monte Carlo simulations reveal the importance of the momentum of the reflected argon neutrals on the phase composition. The maximum energy of these species is mainly defined by the discharge voltage, and is higher than the directional dependent displacement energy of W. Despite the significant correlation between phase composition and the number of displacement per deposited atom, there is a strong scatter of the phase composition. As the deposition conditions were varied in random way, changes of the target erosion profile, and the changing discharge voltage over each series are probably partially responsible for the observed scatter. This scatter is also enhanced by the long term changes in the phase composition towards the more thermodynamic stable <span><math><mi>α</mi></math></span>-W phase.</div></div>","PeriodicalId":22009,"journal":{"name":"Surface & Coatings Technology","volume":null,"pages":null},"PeriodicalIF":5.3000,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Surface & Coatings Technology","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0257897224010788","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, COATINGS & FILMS","Score":null,"Total":0}
引用次数: 0

Abstract

Sputter deposited tungsten thin films are studied by X-ray diffraction. Two phases can be identified: α-W and β-W based on the observed (110), and (200) and (210) Bragg reflections, respectively. With increasing film thickness (50 to 200 nm), the phase composition shifts from β-W towards α-W. No influence of the base pressure (3 × 10−3–3 × 10−5 Pa) on the phase composition is observed. Also the influence of the argon pressure (0.3 to 0.7 Pa) is rather weak. The strongest shift towards α-W composed thin films is obtained by increasing the discharge power (50 to 250 W). This trend is further studied by energy flux measurements using a calorimetric probe. These measurements rule out a strong change of the substrate temperature, and an impact of the energy flux scaled by the deposition rate (total energy per deposited atom). Test particle Monte Carlo simulations reveal the importance of the momentum of the reflected argon neutrals on the phase composition. The maximum energy of these species is mainly defined by the discharge voltage, and is higher than the directional dependent displacement energy of W. Despite the significant correlation between phase composition and the number of displacement per deposited atom, there is a strong scatter of the phase composition. As the deposition conditions were varied in random way, changes of the target erosion profile, and the changing discharge voltage over each series are probably partially responsible for the observed scatter. This scatter is also enhanced by the long term changes in the phase composition towards the more thermodynamic stable α-W phase.
溅射沉积钨薄膜的相组成
通过 X 射线衍射研究了溅射沉积钨薄膜。根据观察到的(110)、(200)和(210)根据观察到的(110)、(200)和(210)布拉格反射,分别确定了两种相:α-W 和 β-W。随着薄膜厚度(50 至 200 nm)的增加,相组成从 β-W 转向 α-W。基底压力(3 × 10-3-3 × 10-5 Pa)对相组成没有影响。氩气压力(0.3 至 0.7 Pa)的影响也很微弱。增加放电功率(50 到 250 W)时,薄膜向 α-W 构成的转变最为明显。使用量热探测器测量能量通量进一步研究了这一趋势。这些测量结果排除了基底温度发生强烈变化的可能性,也排除了能量通量受沉积率(每个沉积原子的总能量)影响的可能性。测试粒子蒙特卡洛模拟揭示了反射氩中子的动量对相组成的重要性。尽管相组成与每个沉积原子的位移数之间存在显著的相关性,但相组成却有很大的分散性。由于沉积条件是随机变化的,目标侵蚀轮廓的变化以及每个系列放电电压的变化可能是造成观察到的散射的部分原因。相组成长期向热力学上更稳定的 α-W 相变化也加剧了这种散射。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Surface & Coatings Technology
Surface & Coatings Technology 工程技术-材料科学:膜
CiteScore
10.00
自引率
11.10%
发文量
921
审稿时长
19 days
期刊介绍: Surface and Coatings Technology is an international archival journal publishing scientific papers on significant developments in surface and interface engineering to modify and improve the surface properties of materials for protection in demanding contact conditions or aggressive environments, or for enhanced functional performance. Contributions range from original scientific articles concerned with fundamental and applied aspects of research or direct applications of metallic, inorganic, organic and composite coatings, to invited reviews of current technology in specific areas. Papers submitted to this journal are expected to be in line with the following aspects in processes, and properties/performance: A. Processes: Physical and chemical vapour deposition techniques, thermal and plasma spraying, surface modification by directed energy techniques such as ion, electron and laser beams, thermo-chemical treatment, wet chemical and electrochemical processes such as plating, sol-gel coating, anodization, plasma electrolytic oxidation, etc., but excluding painting. B. Properties/performance: friction performance, wear resistance (e.g., abrasion, erosion, fretting, etc), corrosion and oxidation resistance, thermal protection, diffusion resistance, hydrophilicity/hydrophobicity, and properties relevant to smart materials behaviour and enhanced multifunctional performance for environmental, energy and medical applications, but excluding device aspects.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信