The hexagonal crystal polytype SiGe (Hex-SiGe), as pioneered by the SiLAS consortium, a predecessor of the Opto Silicon consortium, recently emerged as a new direct bandgap semiconductor. This is seen in the Figure on the right and published in this Nature paper.
Figure on the right shows the measured photoluminescence, and its normalized intensity. The hex-Ge shells were grown on lattice-matching GaAs cores where the hex-Ge is grown at a temperature of 600 °C. On the far right its tunability covers a range from 1.8 to 4.2 µm.
Finally, hex-SiGe is capable to operate in the radiative limit (absence of nonradiative losses) at room temperature, which is quite exceptional in comparison with many III-V semiconductors. This provides a first indication that the superiority of Si-based technology also applies to optical emission of Hex-SiGe.
Figure on the right shows the measured photoluminescence, and its normalized intensity. The hex-Ge shells were grown on lattice-matching GaAs cores where the hex-Ge is grown at a temperature of 600 °C. On the far right its tunability covers a range from 1.8 to 4.2 µm.
Finally, hex-SiGe is capable to operate in the radiative limit (absence of nonradiative losses) at room temperature, which is quite exceptional in comparison with many III-V semiconductors. This provides a first indication that the superiority of Si-based technology also applies to optical emission of Hex-SiGe.