THE ROLE OF CARRIER GASES IN THE EPITAXIAL-GROWTH OF BETA-SIC ON SI BY CVD

Hydrogen:argon mixtures of varying composition were used as carrier gas for CVD growth of silicon carbide from silane and propane at one atmosphere for temperatures ranging from 1100 to 1350-degrees-C. While mixtures of hydrogen and argon give a lower silicon carbide growth rate than obtainable with pure hydrogen carrier gas, they permit monocrystalline growth of silicon carbide at substrate temperatures as low as 1150-degrees-C. Above 1150-degrees-C, growth rates in a 1:1 hydrogen:argon carrier gas mixture decrease with increasing temperature. Simple explanations, consistent with the known system chemistry, are offered for the above phenomena.