Ming-Jie Zhao , Yao-Tian Wang , Jia-Hao Yan , Hai-Cheng Li , Hua Xu , Dong-Sing Wuu , Wan-Yu Wu , Feng-Min Lai , Shui-Yang Lien , Wen-Zhang Zhu
{"title":"Dielectric properties of hafnium oxide film prepared by HiPIMS at different O2/Ar ratios and their influences on TFT performance","authors":"Ming-Jie Zhao , Yao-Tian Wang , Jia-Hao Yan , Hai-Cheng Li , Hua Xu , Dong-Sing Wuu , Wan-Yu Wu , Feng-Min Lai , Shui-Yang Lien , Wen-Zhang Zhu","doi":"10.1016/j.jsamd.2024.100722","DOIUrl":null,"url":null,"abstract":"<div><p>High-<em>k</em> hafnium oxide (HfO<sub>2</sub>) film was prepared by high power impulse magnetron sputtering (HiPIMS). The influences of oxygen supply on the plasma state, film properties and TFT performance were investigated. The films are near-stoichiometric and preferentially (−1 1 1)-orientated. When the oxygen supply increased from 1% to 3%, the excitation/ionization rate of the plasma species increased, leading to higher crystallinity, higher density, and lower oxygen vacancy defect concentration of the film, therefore improving the dielectric properties of the film. When the oxygen supply further increased to 5%, the excitation/ionization rate decreased, thereby leading to lower crystallinity, lower density, and higher oxygen vacancy defect concentration of the film, therefore deteriorating the dielectric properties of the film. The film deposited at 3% oxygen supply exhibited the best dielectric properties with the highest <em>k</em> value of 24 and the highest breakdown-electric field (4.7 MV/cm), which should be attributed to the high crystallinity, high density and low oxygen vacancy defect concentration of the film. Finally, transparent thin film transistors (TFTs) with ITO gate electrode, HfO<sub>2</sub> gate dielectric layer and indium-gallium-zinc oxide channel were fabricated on flexible colorless polyimide substrate at full room temperature by all HiPIMS process. The fixed positive charges and <em>k</em> value of HfO<sub>2</sub> film have significant effects on the TFT performance. The best TFT exhibited good electrical performance, featuring a remarkably low subthreshold swing of 0.13 V/decade. It also exhibited fair stability against bending and gate bias stress.</p></div>","PeriodicalId":17219,"journal":{"name":"Journal of Science: Advanced Materials and Devices","volume":null,"pages":null},"PeriodicalIF":6.7000,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2468217924000534/pdfft?md5=1db80a6467e4defdb65edc0c511592ef&pid=1-s2.0-S2468217924000534-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Science: Advanced Materials and Devices","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2468217924000534","RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
High-k hafnium oxide (HfO2) film was prepared by high power impulse magnetron sputtering (HiPIMS). The influences of oxygen supply on the plasma state, film properties and TFT performance were investigated. The films are near-stoichiometric and preferentially (−1 1 1)-orientated. When the oxygen supply increased from 1% to 3%, the excitation/ionization rate of the plasma species increased, leading to higher crystallinity, higher density, and lower oxygen vacancy defect concentration of the film, therefore improving the dielectric properties of the film. When the oxygen supply further increased to 5%, the excitation/ionization rate decreased, thereby leading to lower crystallinity, lower density, and higher oxygen vacancy defect concentration of the film, therefore deteriorating the dielectric properties of the film. The film deposited at 3% oxygen supply exhibited the best dielectric properties with the highest k value of 24 and the highest breakdown-electric field (4.7 MV/cm), which should be attributed to the high crystallinity, high density and low oxygen vacancy defect concentration of the film. Finally, transparent thin film transistors (TFTs) with ITO gate electrode, HfO2 gate dielectric layer and indium-gallium-zinc oxide channel were fabricated on flexible colorless polyimide substrate at full room temperature by all HiPIMS process. The fixed positive charges and k value of HfO2 film have significant effects on the TFT performance. The best TFT exhibited good electrical performance, featuring a remarkably low subthreshold swing of 0.13 V/decade. It also exhibited fair stability against bending and gate bias stress.
期刊介绍:
In 1985, the Journal of Science was founded as a platform for publishing national and international research papers across various disciplines, including natural sciences, technology, social sciences, and humanities. Over the years, the journal has experienced remarkable growth in terms of quality, size, and scope. Today, it encompasses a diverse range of publications dedicated to academic research.
Considering the rapid expansion of materials science, we are pleased to introduce the Journal of Science: Advanced Materials and Devices. This new addition to our journal series offers researchers an exciting opportunity to publish their work on all aspects of materials science and technology within the esteemed Journal of Science.
With this development, we aim to revolutionize the way research in materials science is expressed and organized, further strengthening our commitment to promoting outstanding research across various scientific and technological fields.