Surface states boost conductivity of Ge nanocrystals
"Ge nanocrystals are promising materials for developing nanoscale optoelectronic devices, such as band-gap engineered tandem solar cells, thanks to low processing temperatures and full compatibility with large-scale integrated circuit fabrication. Many groups have successfully developed technologies to synthesize Ge nanocrystals embedded in SiO2 thin films and to control the structural and optical properties of the nanocomposite. Nevertheless, implementation in practical devices has rarely been demonstrated. This can be partially attributed to the difficulty in making electrically conductive thin films."