TY - GEN
T1 - Steps of surface etching and carbon deposition on the graphite basal plane
AU - Chu, Xi
AU - Chan, Vincent
AU - Schmidt, Lanny D.
PY - 1993
Y1 - 1993
N2 - The reactions of O2, H2O, CO2, NO2, NO, and N2O with single crystal graphite between 400 and 700 °C have been studied by STM to obtain quantitative kinetics by measuring the number and size of monolayer pits on the basal plane versus temperature and time. At low temperature the reaction initiates exclusively from the point defects on the basal plane to form monolayer pits. The shape of the monolayer pits vary from nearly triangular to hexagonal to circular depending on the rate of the reaction and the reacting gases. The sizes of the monolayer pits grow linearly with reacting time. The monolayer reaction rates follow the order of RNO2>RN2O>RNO>RO2>RH2O>RCO2. The activation energies for reactions with O2, H2O, NO2, NO, and N2O, are determined to be 127, 205, 60, 89, and 74 kJ/mol respectively. Carbon deposition from hydrocarbons onto surfaces of single crystal graphite has been examined to study the fundamental steps of chemical vapor deposition. Uniform monolayer pits on graphite surface were first produced by reactive etching of freshly cleaved single crystal of graphite in oxygen and carbon was then made to deposit exclusively on these defects in the basal plane. Carbon vapor deposition forms unique structures around the monolayer steps. By measuring the sizes of structures on steps in various gases versus temperature and pressure, the kinetics of hydrocarbon decomposition and the role of surface diffusion can be determined.
AB - The reactions of O2, H2O, CO2, NO2, NO, and N2O with single crystal graphite between 400 and 700 °C have been studied by STM to obtain quantitative kinetics by measuring the number and size of monolayer pits on the basal plane versus temperature and time. At low temperature the reaction initiates exclusively from the point defects on the basal plane to form monolayer pits. The shape of the monolayer pits vary from nearly triangular to hexagonal to circular depending on the rate of the reaction and the reacting gases. The sizes of the monolayer pits grow linearly with reacting time. The monolayer reaction rates follow the order of RNO2>RN2O>RNO>RO2>RH2O>RCO2. The activation energies for reactions with O2, H2O, NO2, NO, and N2O, are determined to be 127, 205, 60, 89, and 74 kJ/mol respectively. Carbon deposition from hydrocarbons onto surfaces of single crystal graphite has been examined to study the fundamental steps of chemical vapor deposition. Uniform monolayer pits on graphite surface were first produced by reactive etching of freshly cleaved single crystal of graphite in oxygen and carbon was then made to deposit exclusively on these defects in the basal plane. Carbon vapor deposition forms unique structures around the monolayer steps. By measuring the sizes of structures on steps in various gases versus temperature and pressure, the kinetics of hydrocarbon decomposition and the role of surface diffusion can be determined.
UR - http://www.scopus.com/inward/record.url?scp=0027915654&partnerID=8YFLogxK
U2 - 10.1557/proc-312-225
DO - 10.1557/proc-312-225
M3 - Conference contribution
AN - SCOPUS:0027915654
SN - 1558992081
SN - 9781558992085
T3 - Materials Research Society Symposium Proceedings
SP - 225
EP - 230
BT - Common Themes and Mechanisms of Epitaxial Growth
T2 - Materials Research Society Spring Meeting
Y2 - 12 April 1993 through 15 April 1993
ER -