Epitaxial SiGeC/Si photodetector with response in the 1.3-1.55 /spl mu/m wavelength range
We demonstrate a Si-based photodetector with a response in the 1.3-1.55 /spl mu/m wavelength range. The active absorption layer of the pin photodiode consists of a pseudomorphic SiGeC alloy grown on a Si substrate with a Ge content of 55% and a thickness of 800 /spl Aring/. By using a single-mode fiber butt coupled to the waveguide facet, the external quantum efficiency for a 400-/spl mu/m long waveguide is 0.2% at 1.55 /spl mu/m, and 8% at 1.3 /spl mu/m. The external efficiency can be further improved by using a multiple layer absorber structure. The high efficiency and high speed characteristics together with the low leakage current density imply potential application of the SiGeC/Si photodetector for optical fiber communications and optical interconnects in the 1.3-1.55 /spl mu/m wavelength range.