中国物理B ›› 2018, Vol. 27 ›› Issue (4): 48103-048103.doi: 10.1088/1674-1056/27/4/048103

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Structural and electrical properties of reactive magnetron sputtered yttrium-doped HfO2 films

Yu Zhang(张昱), Jun Xu(徐军), Da-Yu Zhou(周大雨), Hang-Hang Wang(王行行), Wen-Qi Lu(陆文琪), Chi-Kyu Choi   

  1. 1. Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, School of Physics, Dalian University of Technology, Dalian 116024, China;
    2. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China;
    3. Department of Physics, Jeju National University, Jeju 63243, Korea
  • 收稿日期:2017-12-01 修回日期:2018-01-12 出版日期:2018-04-05 发布日期:2018-04-05
  • 通讯作者: Jun Xu E-mail:xujun@dlut.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 51272034 and 51672032) and the Fundamental Research Funds for the Central Universities, China (Grant No. DUT17ZD211).

Structural and electrical properties of reactive magnetron sputtered yttrium-doped HfO2 films

Yu Zhang(张昱)1, Jun Xu(徐军)1, Da-Yu Zhou(周大雨)2, Hang-Hang Wang(王行行)1, Wen-Qi Lu(陆文琪)1, Chi-Kyu Choi3   

  1. 1. Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, School of Physics, Dalian University of Technology, Dalian 116024, China;
    2. School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China;
    3. Department of Physics, Jeju National University, Jeju 63243, Korea
  • Received:2017-12-01 Revised:2018-01-12 Online:2018-04-05 Published:2018-04-05
  • Contact: Jun Xu E-mail:xujun@dlut.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 51272034 and 51672032) and the Fundamental Research Funds for the Central Universities, China (Grant No. DUT17ZD211).

摘要:

Hafnium oxide thin films doped with different concentrations of yttrium are prepared on Si (100) substrates at room temperature using a reactive magnetron sputtering system. The effects of Y content on the bonding structure, crystallographic structure, and electrical properties of Y-doped HfO2 films are investigated. The x-ray photoelectron spectrum (XPS) indicates that the core level peak positions of Hf 4f and O 1s shift toward lower energy due to the structure change after Y doping. The depth profiling of XPS shows that the surface of the film is completely oxidized while the oxygen deficiency emerges after the stripping depths have increased. The x-ray diffraction and high resolution transmission electron microscopy (HRTEM) analyses reveal the evolution from monoclinic HfO2 phase towards stabilized cubic HfO2 phase and the preferred orientation of (111) appears with increasing Y content, while pure HfO2 shows the monoclinic phase only. The leakage current and permittivity are determined as a function of the Y content. The best combination of low leakage current of 10-7 A/cm2 at 1 V and a highest permittivity value of 29 is achieved when the doping ratio of Y increases to 9 mol%. A correlation among Y content, phase evolution and electrical properties of Y-doped HfO2 ultra-thin film is investigated.

关键词: Y-doped HfO2, ultra-thin film, high-k, x-ray photoelectron spectrum

Abstract:

Hafnium oxide thin films doped with different concentrations of yttrium are prepared on Si (100) substrates at room temperature using a reactive magnetron sputtering system. The effects of Y content on the bonding structure, crystallographic structure, and electrical properties of Y-doped HfO2 films are investigated. The x-ray photoelectron spectrum (XPS) indicates that the core level peak positions of Hf 4f and O 1s shift toward lower energy due to the structure change after Y doping. The depth profiling of XPS shows that the surface of the film is completely oxidized while the oxygen deficiency emerges after the stripping depths have increased. The x-ray diffraction and high resolution transmission electron microscopy (HRTEM) analyses reveal the evolution from monoclinic HfO2 phase towards stabilized cubic HfO2 phase and the preferred orientation of (111) appears with increasing Y content, while pure HfO2 shows the monoclinic phase only. The leakage current and permittivity are determined as a function of the Y content. The best combination of low leakage current of 10-7 A/cm2 at 1 V and a highest permittivity value of 29 is achieved when the doping ratio of Y increases to 9 mol%. A correlation among Y content, phase evolution and electrical properties of Y-doped HfO2 ultra-thin film is investigated.

Key words: Y-doped HfO2, ultra-thin film, high-k, x-ray photoelectron spectrum

中图分类号:  (Deposition by sputtering)

  • 81.15.Cd
77.55.df (For silicon electronics) 68.55.-a (Thin film structure and morphology) 82.80.Pv (Electron spectroscopy (X-ray photoelectron (XPS), Auger electron spectroscopy (AES), etc.))