S. M. Park

Publications (4)5.9 Total impact

• Article: 1.54 mum emission mechanism of Er-doped zinc oxide thin films

  Y. R. Jang, K. H. Yoo, J. S. Ahn, C. Kim, S. M. Park
  Applied Surface Science - APPL SURF SCI. 01/2011; 257:2822-2824.
• Article: 1.54 μm emission mechanism in Er-doped silicon-rich silicon oxides

  Y. R. Jang, K. H. Yoo, J. S. Ahn, C. Kim, S. M. Park
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  ABSTRACT: Silicon-rich silicon oxide (SRSO) and Er-doped SRSO (SRSO:Er) thin films were formed by pulsed laser deposition, and characterized by photoluminescence (PL), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), and UV-visible transmission in order to clarify the 1.54 μ m emission mechanism in the SRSO:Er films. The oxygen content of the films was varied by the adjustment of oxygen partial pressure. The behavior of the 1.54 μ m PL with oxygen partial pressure combined with XPS and XRD data show that the 1.54 μ m emission intensity is related to the amount of SiO _x phase. This conclusion is well supported by the measurements of UV-visible transmission. In many previous papers, the 1.54 μ m emission is associated with Si nanocrystals, but in our study the correlation between 1.54 μ m emission intensity and the amount of SiO _x phase is much clearer.
  Journal of Applied Physics 10/2009; · 2.17 Impact Factor
• Article: The effects of ambient oxygen pressure on the 1.54 µm photoluminescence of Er-doped silicon-rich silicon oxide films grown by laser ablation of a Si+Er target

  J.S. Ha, G.Y. Sung, S. Lee, Y.R. Jang, K.H. Yoo, C.H. Bae, J.S. Jeon, S.H. Nam, S.M. Park
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  ABSTRACT: We fabricated Er-doped silicon-rich silicon oxide (SRSO:Er) films by pulsed laser deposition. A Si+Er target consisting of an Er metallic strip and a silicon disk was adopted with a goal to achieve a convenient control of the Er and oxygen density in the film. We found that the photoluminescence (PL) at 1.54m is highly dependent on the ambient oxygen pressure, which determines the relative ratio of Si-Si, SiOx, and SiO2 phase in the film. The PL intensity increased drastically with increase in the annealing temperature and reached the maximum intensity at 500C.
  Applied Physics A 01/2004; 79(4):1485-1488. · 1.63 Impact Factor
• Article: 1.54μm emission mechanism of Er-doped zinc oxide thin films

  Y.R. Jang, K.H. Yoo, J.S. Ahn, C. Kim, S.M. Park
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  ABSTRACT: Zinc oxide (ZnO) and Er-doped zinc oxide (ZnO:Er) thin films were formed by pulsed laser deposition, and characterized by photoluminescence (PL) and X-ray diffraction (XRD) in order to clarify the 1.54 μm emission mechanism in the ZnO:Er films. Er ions were excited indirectly by the 325 nm line of a He–Cd laser, and the comparison of the ultraviolet to infrared PL data of ZnO and ZnO:Er films showed that the 1.54 μm emission of Er3+ in ZnO:Er film appears at the expense of the band edge emission and the defect emission of ZnO. The crystallinity of the films was varied with the substrate temperature and post-annealing, and it was found that the intensity of the 1.54 μm emission is strongly related with the crystallinity of the films. There are three processes leading to the 1.54 μm emission; absorption of excitation energy by the ZnO host, energy transfer from ZnO to Er ions, and radiative relaxation inside Er ions, and it is suggested that the crystallinity plays an important role in the first two processes.
  Applied Surface Science 257(7):2822-2824. · 2.10 Impact Factor