News

Korean National Science & Technology Commission A delegation of the Korean National Science & Technology Commission (NSTC) Delegation led by Dr. Cha-Dong Kim visited us on 7 December.
For more information about NSTC visit the website.

Society for the Advancement of Material and Process Engineering During the Society for the Advancement of Material and Process Engineering (SAMPE) Benelex Student meeting, Niels De Greef is selected for the best presentation award together with a student from UCL and is nominated for the JEC award competition, which will be held in conjunction with the SAMPE Europe Student Meeting in Paris, March 2012. Congratulations!

Niels De Greef will receive a KU Leuven policy mandate for one year for his excellent performance. Well done!

Recent Highlights

Correlation between strain and the metal–insulator transition in epitaxial V2O3 thin films grown by Molecular Beam EpitaxyCorrelation between strain and the metal–insulator transition in epitaxial V2O3 thin films grown by Molecular Beam Epitaxy by L. Dillemans et al.,


Deposition and characterization of MgO/Si gate stacksDeposition and characterization of MgO/Si gate stacks grown by molecular beam epitaxy by Chen-Yi Su et al.,


Thermally induced phase separation in PaMSAN/PMMA blends in presence of functionalized multiwall carbon nanotubes: Rheology, morphology and electrical conductivity by Ceren Özdilek et al.,


Striking influence of the catalyst support and its acid-base properties: New insight into the growth mechanism of carbon nanotubes by Arnaud Magrez et al.,


Fabrication of homogeneous titania/MWNT composite materials by Barbara Korbély et al.,


Research

Crystallization of germanium films

We are investigating low cost deposition methods to obtain germanium films on large areas. Such layers enable new and improved large area electronic applications, by using the excellent optical and electrical properties of germanium.

We have developed a method consisting of low temperature deposition and annealing, leading to excellent solid phase epitaxial growth of germanium on silicon substrates.

The advantages of this method are:

  • low thermal budget (400 °C is sufficient)
  • Plasma-enhanced chemical vapor deposition (PECVD) can be used
    » ideal for large scale applications
  • fast overall process (extreme fast deposition and RTA)
  • easily scalable to large areas (> 8 inch)
  • excellent structural quality
  • high electrical quality (carrier mobilities of more than 80 % higher than Si(001) demonstrated)
  • smooth interface (< 1 nm RMS roughness, no mixing)
  • smooth surface (0.4 nm RMS roughness obtained)

FIG. 1. Comparison of X-ray diffraction (XRD) ω/2θ scans of as-deposited (black, solid line with squares) and crystallized (blue, solid line) amorphous Ge on Si(111). An intense and narrow Ge(111) diffraction peak is observed, indicating high crystal quality. The presence of fringes indicates a smooth Ge surface and interface between Ge and Si.


FIG. 2. XRD Reciprocal space map of crystallized Ge on Si(111) for the (331) reflection. The Ge layer is under slight tensile strain, which is induced by thermal mismatch.