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
Alireza Samavatia, Z. Othamana, S. K. Ghoshalb, R. J. Amjadb
Alireza Samavatia, Z. Othamana, S. K. Ghoshalb, R. J. Amjadb
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.
中图分类号: (Nanoscale materials and structures: fabrication and characterization)