中国物理B ›› 2019, Vol. 28 ›› Issue (11): 117303-117303.doi: 10.1088/1674-1056/ab470f

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Hysteresis effect in current-voltage characteristics of Ni/n-type 4H-SiC Schottky structure

Hao Yuan(袁昊), Qing-Wen Song(宋庆文), Chao Han(韩超), Xiao-Yan Tang(汤晓燕), Xiao-Ning He(何晓宁), Yu-Ming Zhang(张玉明), Yi-Men Zhang(张义门)   

  1. School of Microelectronics, Xidian University, Xi'an 710071, China
  • 收稿日期:2019-08-12 修回日期:2019-09-16 出版日期:2019-11-05 发布日期:2019-11-05
  • 通讯作者: Qing-Wen Song E-mail:qwsong@xidian.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61804118, 61774117, and 61774119), the Fundamental Research Funds for the Central Universities, China (Grant Nos. 20101185935 and 20106186647), the National Key Basic Research Program of China (Grant No. 2015CB759600), the Shaanxi Key Research and Development Program, China (Grant No. 2018ZDXM-GY-008), and the Natural Science Basic Research Plan in Shaanxi Province, China (Grant No. 2017JM6003).

Hysteresis effect in current-voltage characteristics of Ni/n-type 4H-SiC Schottky structure

Hao Yuan(袁昊), Qing-Wen Song(宋庆文), Chao Han(韩超), Xiao-Yan Tang(汤晓燕), Xiao-Ning He(何晓宁), Yu-Ming Zhang(张玉明), Yi-Men Zhang(张义门)   

  1. School of Microelectronics, Xidian University, Xi'an 710071, China
  • Received:2019-08-12 Revised:2019-09-16 Online:2019-11-05 Published:2019-11-05
  • Contact: Qing-Wen Song E-mail:qwsong@xidian.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61804118, 61774117, and 61774119), the Fundamental Research Funds for the Central Universities, China (Grant Nos. 20101185935 and 20106186647), the National Key Basic Research Program of China (Grant No. 2015CB759600), the Shaanxi Key Research and Development Program, China (Grant No. 2018ZDXM-GY-008), and the Natural Science Basic Research Plan in Shaanxi Province, China (Grant No. 2017JM6003).

摘要: Hysteresis current-voltage (I-V) characteristics are often observed in a highly non-ideal (n>2) as-deposited nickel (Ni)/4H-SiC Schottky contact. However, we find that this kind of hysteresis effect also exists in an as-deposited Ni/n-type 4H-SiC Schottky structure even if the ideality factor (n) is less than 1.2. The hysteresis I-V characteristics is studied in detail in this paper by using the various measurements including the hysteresis I-V, sequential I-V sweeping, cycle I-V, constant reverse voltage stress (CRVS). The results show that the hysteresis I-V characteristics are strongly dependent on the sweeping voltage and post-deposition annealing (PDA). The high temperature PDA (800℃) can completely eliminate this hysteresis. Meanwhile, the magnitude of the hysteresis effect is shown to decrease in the sequential I-V sweeping measurement, which is attributed to the fact that the electrons tunnel from the 4H-SiC to the localized states at the Ni/n-type 4H-SiC interface. It is found that the application of the reverse bias stress has little effect on the emission of those trapped electrons. And a fraction of the trapped electrons will be gradually released with the time under the condition of air and with no bias. The possible physical charging mechanism of the interface traps is discussed on the basis of the experimental findings.

关键词: 4H-SiC, Schottky, hysteresis I-V, Schottky barrier height

Abstract: Hysteresis current-voltage (I-V) characteristics are often observed in a highly non-ideal (n>2) as-deposited nickel (Ni)/4H-SiC Schottky contact. However, we find that this kind of hysteresis effect also exists in an as-deposited Ni/n-type 4H-SiC Schottky structure even if the ideality factor (n) is less than 1.2. The hysteresis I-V characteristics is studied in detail in this paper by using the various measurements including the hysteresis I-V, sequential I-V sweeping, cycle I-V, constant reverse voltage stress (CRVS). The results show that the hysteresis I-V characteristics are strongly dependent on the sweeping voltage and post-deposition annealing (PDA). The high temperature PDA (800℃) can completely eliminate this hysteresis. Meanwhile, the magnitude of the hysteresis effect is shown to decrease in the sequential I-V sweeping measurement, which is attributed to the fact that the electrons tunnel from the 4H-SiC to the localized states at the Ni/n-type 4H-SiC interface. It is found that the application of the reverse bias stress has little effect on the emission of those trapped electrons. And a fraction of the trapped electrons will be gradually released with the time under the condition of air and with no bias. The possible physical charging mechanism of the interface traps is discussed on the basis of the experimental findings.

Key words: 4H-SiC, Schottky, hysteresis I-V, Schottky barrier height

中图分类号:  (Metal-nonmetal contacts)

  • 73.40.Ns