Growth and photoluminescence of high quality SiGeC random alloys on silicon substrates

Abstract

We report chemical vapor deposition growth of SiGeC layers on ͗100͘ Si substrates. At the growth temperature of 550°C, the C concentration as high as 2% can be incorporated into SiGe ͑Ge content ϳ 25%͒ to form single crystalline random alloys by using low flow of methylsilane ͑0.25 sccm͒ as a C precursor added in a dichlorosilane and germane mixture. For intermediate methylsilane flow ͑0.5 sccm-1.5 sccm͒, the Fourier transform infrared spectroscopy ͑FTIR͒ absorption spectra indicate the growth of amorphous layers. For the layers with high flow of methylsilane ͑12 sccm͒, there are silicon-carbide-like peaks in the FTIR spectra, indicating silicon carbide precipitation. The films were also characterized by x-ray diffraction, high resolution transmission electron microscopy, secondary ion mass spectroscopy, and Rutherford backscattering spectroscopy to confirm crystallinity and constituent fractions. The defect-free band-edge photoluminescence at both 30 K and 77 K was observed in Si/SiGeC/Si quantum wells, even at power densities as low as 0.5 W/ cm 2 and 1 W/cm 2 , respectively. Deep photoluminescence around 0.8 eV and luminescence due to D 3 dislocations at 0.94 eV were not observed under any excitation conditions.

Ion beam synthesis of cubic-SiC layer on Si(111) substrate

“…[5][6][7][8][9][10][11][12] Some straightforward advantages are cheaper and larger substrate area, Si-SiC device integration, Si-GaN device integration through a SiC intermediate layer, and thermal dissipation improvement of GaN devices, since Si thermal conductivity is almost the same as the GaN. In this work, we are investigating the possibility of obtaining a SiC layer on Si͑111͒ by using ion implantation technique, which is deeply employed in Si processing steps.…”

Band offsets in Si/Si1−x−yGexCy heterojunctions measured by admittance spectroscopy

“…Recently, impressive progress has been made in the growth and characterization of Si 1ϪxϪy Ge x C y alloys. [1][2][3][4][5] Si 1ϪxϪy Ge x C y offers considerably greater flexibility, compared to that available in the Si/Si 1Ϫx Ge x material system, to control strain and electronic properties in Group IV heterostructures, and leads to the possibility of fabricating Group IV heterostructure devices lattice matched to Si. [1][2][3][4][5][6] Effective design, fabrication, and characterization of such devices, however, requires the accurate measurement of the energy band offsets in Si/Si 1ϪxϪy Ge x C y heterojunctions.…”

Boron segregation and electrical properties in polycrystalline Si1−x−yGexCy and Si1−yCy alloys

“…Previous work shows that for single-crystal Si 1ϪxϪy Ge x C y and Si 1Ϫy C y films grown under similar conditions as those used for this study, most of the carbon is substitutional. 8,9 All layers were grown on thermally oxidized silicon substrates. Grain sizes in the polycrystalline Si 1ϪxϪy Ge x C y layers, from plan-view transmission electron microscopy ͑TEM͒, were observed to be about ϳ40 nm.…”