Structural studies of multilayered Ge nanocrystals embedded in matrix fabricated using magnetron sputtering

Ge nanocrystals (Ge NCs) were grown in a multilayered superlattice structure using magnetron co-sputtering technology. Studies were taken to optimize the processing conditions including post-annealing temperature and duration. Structural properties of Ge NCs and multi-bilayers, such as crystallization process, precipitate crystallinity, size-control of nanocrystals and influence of interlayer diffusion, were particularly chosen to be investigated. The experimental results indicated that high quality and reproducible multilayered Ge NCs can be obtained with an appropriate thermal annealing condition. This investigation builds a technical foundation for fabrication of tandem solar cell applicable Ge NCs absorber films.