On the formation of blisters in annealed hydrogenated a-Si layers


Differently hydrogenated radio frequency-sputtered a-Si layers have been studied by infrared (IR) spectroscopy as a function of the annealing time at 350°C with the aim to get a deeper understanding of the origin of blisters previously observed by us in a-Si/a-Ge multilayers prepared under the same conditions as the ones applied to the present a-Si layers. The H content varied between 10.8 and 17.6 at.% as measured by elastic recoil detection analysis. IR spectroscopy showed that the concentration of the clustered (Si-H)n groups and of the (Si-H2)n (n ≥ 1) polymers increased at the expense of the Si-H mono-hydrides with increasing annealing time, suggesting that there is a corresponding increase of the volume of micro-voids whose walls are assumed from literature to be decorated by the clustered mono-hydride groups and polymers. At the same time, an increase in the size of surface blisters was observed. Also, with increasing annealing time, the total concentration of bonded H of any type decreases, indicating that H is partially released from its bonds to Si. It is argued that the H released from the (Si-H)n complexes and polymers at the microvoid surfaces form molecular H2 inside the voids, whose size increases upon annealing because of the thermal expansion of the H2 gas, eventually producing plastic surface deformation in the shape of blisters.

DOI: 10.1186/1556-276X-8-84

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Showing 1-10 of 27 references

Nanoscale Research Letters

  • Serényi
  • 2013

Light-induced annealing of hole trap states: a new aspect of light-induced changes in hydrogenated amorphous silicon

  • I Sakata, T Kamei, M Yamanaka
  • 2012

Voids in hydrogenated amorphous silicon materials

  • W Beyer, W Hilgers, P Prunici, D Lennartz
  • 2012

Structural, optical and electrical properties of amorphous silicon thin films prepared by sputtering with different targets

  • Y Qin, T Feng, Z Li, Z Sun
  • 2011

A study of optical absorption in amorphous hydrogenated silicon thin films of varied thickness

  • J Müllerová, L Prusáková, M Netrvalová, V Vavrunková, P Sutta
  • 2010

AFM and TEM study of hydrogenated sputtered Si/Ge multilayers

  • C Frigeri, L Nasi, M Serényi, A Csik, Z Erdélyi, Dl Beke
  • 2009

Changes in surface topography of amorphous silicon germanium films after light soaking

  • P Agarwal, A Srivastava, D Deva
  • 2007

Optical properties of amorphous films of an a-Si 1–x Ge x :H solid solution with different concentrations of hydrogen

  • Ba Nadzhafov, Gi Isakov
  • 2005

Vacancies and voids in hydrogenated amorphous silicon

  • Ahm Smets, Wmm Kessels, Mcm Van De Sanden
  • 2003