Fully coherent Ge islands growth on Si nano-pillars by selective epitaxy

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Yuji Yamamoto - , Leibniz Institute for High Performance Microelectronics (Author)
  • Peter Zaumseil - , Leibniz Institute for High Performance Microelectronics (Author)
  • Markus Andreas Schubert - , Leibniz Institute for High Performance Microelectronics (Author)
  • Giovanni Capellini - , Roma Tre University (Author)
  • Marco Salvalaglio - , TUD Dresden University of Technology (Author)
  • F. Montalenti - , University of Milan - Bicocca (Author)
  • Thomas Schroeder - , Brandenburg University of Technology (Author)
  • Bernd Tillack - , Technical University of Berlin (Author)

Abstract

Our recent experimental results of Ge nanoheteroepitaxy (NHE) on Si nanopillars (NPs) are reviewed to confirm the possibility of relaxed Ge growth on Si without misfit dislocations (MDs) formation by elastic deformation. Selective Ge growth is performed by using reduced pressure chemical vapor deposition (CVD) on two types of Si NPs with thermal SiO2 or CVD SiO2 sidewalls and on Si nanoislands (NIs) on SiO2. By using thermal SiO2 sidewall, compressive strain is generated in the Si pillar and fixed by the thermal SiO2. This results in an incoherent Ge growth on Si NPs due to MD formation. By using CVD SiO2 sidewall, tensile strain formation due to thermal expansion during prebake for Ge epi process is observed. However, strain in Si due to Ge growth is not dominant. By introducing a Si0.5Ge0.5 buffer layer, no MD and stacking faults are observed by cross section TEM. The shape of Ge on Si NPs becomes more uniform due to improved crystal quality. On Si Nis on SiO2, a clear compliance effect is observed after Ge growth. Coherent growth of Ge on Si is also realized on Si NIs by using Si0.5Ge0.5 buffer.

Details

Original languageEnglish
Pages (from-to)30-37
Number of pages8
JournalMaterials science in semiconductor processing
Volume70
Publication statusPublished - 1 Nov 2017
Peer-reviewedYes
Externally publishedYes

Conference

Title7th International Symposium on Control of Semiconductor Interfaces (ISCSI) / 8th International Silicon-Germanium Technology and Device Meeting (ISTDM)
Duration7 - 11 June 2016
CityNagoya
CountryJapan

External IDs

Scopus 85001755212
ORCID /0000-0002-4217-0951/work/142237422

Keywords

Keywords

  • Selective Ge epitaxy, Heteroepitaxial growth, Coherent growth, Strain, Relaxation, CHEMICAL-VAPOR-DEPOSITION, SILICON, LAYERS, NANOHETEROEPITAXY, HETEROEPITAXY, PHOTODIODE