Here, we present work on epitaxial Ge films grown on a thin buffer layer of C doped Ge (Ge:C). The growth rate of Ge:C is found to slow over time and is thus unsuitable for thick (>20 nm) layers. We demonstrate Ge films from 10 nm to >150 nm are possible by growing pure Ge on a thin Ge:C buffer. It is shown that this stack yields exceedingly low roughness levels (comparable to bulk Si wafers) and contains fewer defects and higher Hall mobility compared to traditional heteroepitaxial Ge. The addition of C at the interface helps reduce strain by its smaller atomic radius and its ability to pin defects within the thin buffer layer that do not thread to the top Ge layer. © 2013 AIP Publishing LLC.
|Original language||English (US)|
|Journal||Applied Physics Letters|
|State||Published - May 17 2013|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This work was supported in part by a grant from KAUST and the NSF NNIN program.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.