Solid source molecular beam epitaxy is used to explore the growth of carbon films directly on Si(111). It is shown that graphitic carbon is grown by the implementation of a thin amorphous carbon film that suppresses the formation of SiC precipitates. Raman scattering measurements show the D and G vibrational phonon modes, indicating graphitic ordering in the carbon film. X-ray photoelectron spectroscopy is used to verify the formation of sp2 bonds in the graphitic carbon films and confirms the suppression of SiC.

The authors report on the design, characterization, and performance of silicon-rich SiGe waveguide photodetectors grown directly on silicon without virtual buffer relaxation layers. The type-II band offsets of the SiGe system is used to engineer a "W-structure" for absorption at 1.3 m. Multimode waveguide devices are found to have a responsivity of 13.2 mA/ W and a specific detectivity of 1.8ϫ 10 8 cm Hz 1/2 W −1 at 1.3 m. Variation in the responsivity versus length of single-mode waveguide devices was used to characterize the material, yielding an optical absorption coefficient of 11.21 cm −1 for a single active region that is 25 Å thick. The 500 m long single-mode devices exhibit a 3 dB bandwidth of 1.54 GHz.

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