Titanium-Catalyzed Silicon Nanostructures Grown by APCVD

Titanium catalyzed silicon nanowires and nanoplatelets

“…Substrates were first heated in a hydrogen carrier gas stream a atifumar@yahoo.com and annealed for up to 15 minutes at either the growth temperature or 1000 • C before introducing the silicon precursor, SiCl 4 , from a bubbler into the system. 25 Growth temperatures ranged from 750 • C to 1000 • C in 25 • C increments, SiCl 4 partial pressures from 0.67 to 3.25 mbar, and growth times from about 3 minutes to 80 minutes.Post-growth characterizations included imaging with either a Leica 440i or a FEI Nova Nano SEM scanning electron microscope (SEM). Figure 1 gives SEM images from growths exhibiting combinations of nanowires, surface etching, and uncatalyzed silicon deposition.…”

“…Overall, growth results at times proved enigmatic, with some nominally similar conditions producing no growth, a low density of etching features, or only a low density of nucleated nanowires. 25 Figure 2 gathers SEM micrographs that span the range of platelet morphologies found in the growth condition survey. These two-dimensional shapes were only observed for growth temperatures of 900 and 925 • C. The top six panels come from four 900 • C growths.…”