Peer-Reviewed Journal Details
Mandatory Fields
Doherty, J.; Biswas, S.; Gallucio, E.; Broderick, C. A.; Garcia-Gil, A.; Duffy, R.; O’Reilly, E. P.; Holmes, J. D.
Chemistry of Materials
Progress on germanium-tin nanoscale alloys
Optional Fields
Photonic devices Nanoelectronic devices Optotelectronic devices Ge1-xSnx thin films Ge1-xSnx strain-relaxed one dimensional (1D) nanostructures Nanoparticles
Group IV alloys have attracted interest in the drive to create Si compatible, direct bandgap materials for implementation in complementary metal oxide semiconductor (CMOS) and beyond CMOS devices. The lack of a direct bandgap in Si and Ge hinders their incorporation into optoelectronic and photonic devices, without the induction of undesirable strain. Alloying of Ge with Sn represents a novel solution to the lack of light emission in group IV compounds, with an indirect-to-direct bandgap transition predicted for Ge at a Sn incorporation greater than 6.5 at. %. Recently, the initiatives on GeSn alloy research has turned its focus on nanoforms to keep track with the miniaturization of Si-related platforms for application in nano/optoelectronics, photonics and energy devices. Here, we review recent advances in the growth and application of Ge1-xSnx nanomaterials. An overview of theoretical band structure calculations for Ge1-xSnx and the effect of band-mixing is briefly explored to highlight the significance of Sn inclusion in Ge for band gap engineering. Different fabrication methods for growing Ge1-xSnx alloy nanostructures are delineated and corelated with thin films growth. This highlight the requirement of low-temperature, kinetically-driven non-equilibrium processess for growing these metastable nanoscale alloys. The optical and electrical properties for both Ge1-xSnx strain-relaxed one dimensional (1D) nanostructures and nanoparticles are reported with additional highlight on the recent key findings on Ge1-xSnx thin films to indicate the potential application of these materials in photonic, nanoelectronic and optotelectronic devices.
Grant Details