中国物理B ›› 2013, Vol. 22 ›› Issue (9): 98102-098102.doi: 10.1088/1674-1056/22/9/098102

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

Germanium nanoislands grown by radio frequency magnetron sputtering:Annealing time dependent surface morphology and photoluminescence

Alireza Samavatia, Z. Othamana, S. K. Ghoshalb, R. J. Amjadb   

  1. a Ibn Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, 81310 Skudai, Johor Baharu, Malaysia;
    b Advanced Optical Material Research Group, Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor, Malaysia
  • 收稿日期:2013-03-04 修回日期:2013-03-21 出版日期:2013-07-26 发布日期:2013-07-26
  • 基金资助:
    Project supported by the International Doctoral Fellowship (IDF), Ibnu Sina Institute for Fundamental Science Study and research grants of MoHE GUP. Vot No. 02H94 and 07J80.

Germanium nanoislands grown by radio frequency magnetron sputtering:Annealing time dependent surface morphology and photoluminescence

Alireza Samavatia, Z. Othamana, S. K. Ghoshalb, R. J. Amjadb   

  1. a Ibn Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, 81310 Skudai, Johor Baharu, Malaysia;
    b Advanced Optical Material Research Group, Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor, Malaysia
  • Received:2013-03-04 Revised:2013-03-21 Online:2013-07-26 Published:2013-07-26
  • Contact: Z. Othaman E-mail:zulothaman@gmail.com
  • Supported by:
    Project supported by the International Doctoral Fellowship (IDF), Ibnu Sina Institute for Fundamental Science Study and research grants of MoHE GUP. Vot No. 02H94 and 07J80.

摘要: Structural and optical properties of ~ 20 nm Ge nanoislands grown on Si(100) by radio frequency (rf) magnetron sputtering under varying annealing conditions are reported. Rapid thermal annealing at a temperature of 600℃ for 30 s, 90 s, and 120 s are performed to examine the influence of annealing time on the surface morphology and photoluminescence properties. X-ray diffraction spectra reveal prominent Ge and GeO2 peaks highly sensitive to the annealing time. Atomic force microscope micrographs of the as-grown sample show pyramidal nanoislands with relatively high-density (~ 1011 cm-2). The nanoislands become dome-shaped upon annealing through a coarsening process mediated by Oswald ripening. The room temperature photoluminescence peaks for both as-grown (~ 3.29 eV) and annealed (~ 3.19 eV) samples consist of high intensity and broad emission, attributed to the effect of quantum confinement. The red shift (~ 0.10 eV) of the emission peak is attributed to the change in the size of the Ge nanoislands caused by annealing. Our easy fabrication method may contribute to the development of Ge nanostructure-based optoelectronics.

关键词: germanium nanoislands, radio frequency magnetron sputtering, photoluminescence, surface morphology

Abstract: Structural and optical properties of ~ 20 nm Ge nanoislands grown on Si(100) by radio frequency (rf) magnetron sputtering under varying annealing conditions are reported. Rapid thermal annealing at a temperature of 600℃ for 30 s, 90 s, and 120 s are performed to examine the influence of annealing time on the surface morphology and photoluminescence properties. X-ray diffraction spectra reveal prominent Ge and GeO2 peaks highly sensitive to the annealing time. Atomic force microscope micrographs of the as-grown sample show pyramidal nanoislands with relatively high-density (~ 1011 cm-2). The nanoislands become dome-shaped upon annealing through a coarsening process mediated by Oswald ripening. The room temperature photoluminescence peaks for both as-grown (~ 3.29 eV) and annealed (~ 3.19 eV) samples consist of high intensity and broad emission, attributed to the effect of quantum confinement. The red shift (~ 0.10 eV) of the emission peak is attributed to the change in the size of the Ge nanoislands caused by annealing. Our easy fabrication method may contribute to the development of Ge nanostructure-based optoelectronics.

Key words: germanium nanoislands, radio frequency magnetron sputtering, photoluminescence, surface morphology

中图分类号:  (Nanoscale materials and structures: fabrication and characterization)

  • 81.07.-b
78.67.-n (Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures) 79.20.Rf (Atomic, molecular, and ion beam impact and interactions with surfaces)