The protection from the effects of gamma rays of metal-semiconductor diodes by means of ZnO thin interface layer

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Salari M. A., SAĞLAM M., Güzeldir B.

RADIATION PHYSICS AND CHEMISTRY, cilt.165, 2019 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 165
  • Basım Tarihi: 2019
  • Doi Numarası: 10.1016/j.radphyschem.2019.108416
  • Dergi Adı: RADIATION PHYSICS AND CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: Thin films, Sputtering technique, Zinc oxide, Gamma rays, Schottky diode, CURRENT-VOLTAGE CHARACTERISTICS, ELECTRICAL CHARACTERISTICS, ION IRRADIATION, SI/AL, AL, SI
  • Atatürk Üniversitesi Adresli: Evet

Özet

In this study, the protective effects of Zinc oxide (ZnO) interfacial layer in the Zn/n-Si rectifying contacts against gamma radiation were investigated. In the fabrication of the diodes, n-type Si is used as a semiconductor. First, an ohmic contact is made by using Au-Sb alloy on the polished surface of the n-Si. Afterwards, the ZnO thin film is grown on the n-type Si semiconductor substrate by the RF magnetron sputtering technique. The structural properties of ZnO thin films are investigated by x-ray diffraction (XRD) measurements. It is found that ZnO films are polycrystalline. Current-voltage (I-V) measurements of Zn/n-Si/Au-Sb and Zn/ZnO/n-Si/Au--Sb diodes which are fabricated under laboratory conditions are taken at room temperature in the dark. The basic electrical parameters such as ideality factor (n), barrier height (Phi(b), series resistance (R-s), rectifying ratio (RR) and interface state density (N-ss) of diodes are calculated from the forward bias I-V characteristics. To examine the effects of gamma radiation on the electrical parameters, the diodes are exposed to gamma rays using barium-133, americium-241, and cobalt-60 gamma sources. After irradiation, I-V measurements of diodes are taken again, the characteristic parameters are calculated and the results are compared with the previous ones.

In this study, the protective effects of Zinc oxide (ZnO) interfacial layer in the Zn/n-Si rectifying contacts against gamma radiation were investigated. In the fabrication of the diodes, n-type Si is used as a semiconductor. First, an ohmic contact is made by using Au–Sb alloy on the polished surface of the n-Si. Afterwards, the ZnO thin film is grown on the n-type Si semiconductor substrate by the RF magnetron sputtering technique. The structural properties of ZnO thin films are investigated by x-ray diffraction (XRD) measurements. It is found that ZnO films are polycrystalline. Current-voltage (I–V) measurements of Zn/n-Si/Au–Sb and Zn/ZnO/n-Si/Au–Sb diodes which are fabricated under laboratory conditions are taken at room temperature in the dark. The basic electrical parameters such as ideality factor (n), barrier height (Φb), series resistance (Rs), rectifying ratio (RR) and interface state density (Nss) of diodes are calculated from the forward bias I–V characteristics. To examine the effects of gamma radiation on the electrical parameters, the diodes are exposed to gamma rays using barium- 133, americium-241, and cobalt-60 gamma sources. After irradiation, I–V measurements of diodes are taken again, the characteristic parameters are calculated and the results are compared with the previous ones.