Fabrication of Si nanocrystals in an amorphous SiC matrix by magnetron sputtering


İMER A., YILDIZ İ. , TURAN R.

PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES, cilt.42, ss.2358-2363, 2010 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 42 Konu: 9
  • Basım Tarihi: 2010
  • Doi Numarası: 10.1016/j.physe.2010.05.013
  • Dergi Adı: PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
  • Sayfa Sayıları: ss.2358-2363

Özet

Si nanocrystals embedded in a wide bandgap material have been of interest for various electronic devices, including third-generation solar cells with efficiency values exceeding theoretical limits. In this work, Si-rich amorphous SiC layers with different Si contents were fabricated by the RF magnetron sputtering deposition technique. Si nanocrystal formation was induced by a high-temperature annealing process in a series of samples with different Si contents controlled by the DC power applied to the Si target during the sputtering. Nanocrystal formation was monitored to understand the basic kinetics as a function of process parameters, such as DC power and annealing temperature. In the SiC films containing excess Si, nanocrystal formation was clearly identified by Raman spectroscopy and high-resolution Transmission Electron Microscopy (TEM). Si nanocrystals with a mean size of 2 nm were imaged by TEM in the samples annealed at 1100 degrees C. The presence of Si-Si bonds was also detected by XPS through a series of experiments, including depth profiling of the chemical bonds of O, Si and C as a function of depth from the surface. Infrared spectroscopy was employed to study the stoichiometry of the SiC matrix with or without nanocrystals. (C) 2010 Elsevier B.V. All rights reserved.