1990 年 41 巻 8 号 p. 829-833
The effects of selected gases readily available as carbon sources, -including propane, butane and alcohols-on diamond deposits on Si wafers by microwave plasma CVD were compared in terms of rate of deposition efficiency and cost.
The maximum deposition rate for C3H8-H2 system was 1.5 times faster than that of CH4-H2, while those of the C6H6- and C2H5OH-H2 systems were two times faster, but it was not possible to obtain rates proportional to carbon densities.
At corresponding C/H ratios in each gas, hydrogen-diluted LPG′ gas can achieve a deposition rate comparable with methane and at reduced cost of a factor of up to 8.
Alcohols and other compounds containg oxygen provide higher controllability and a wider range of usable concentrations than do hydrocarbons, as amorphous carbon is etched efficiently by oxygen, but the large volumes required make them prohibitively expensive.