Generation of a Two-Dimensional Silicon Carbide Lattice
Silicon carbide was generated by pyrolysis of gas mixtures consisting of silicon tetrachloride, hydrogen, and organic vapors, such as acetone, on fine tungsten wires resistance-heated at 1500°C. Prominent two-dimensional structure was demonstrated for the 220 reflection. All other lines were of the normal three-dimensional lattice type.
Elevation of less than 100° in the pyrolysis temperature eliminated the two-dimensional reflection, and simultaneously changed the visible crystallite size.
Specialized techniques were used to generate the silicon carbide deposits and also to examine the structure of these deposits by X-ray diffraction to obtain lines from only the silicon carbide while ignoring the tungsten wire core. Diffraction techniques include offset collimation and vertical integration.
KeywordsSilicon Carbide Pyrolysis Temperature Vertical Integration Tungsten Wire Silicon Tetrachloride
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