This paper used optical emission spectroscopy （OES） to study the gas phase in high power DC arc plasma jet chemical vapour deposition （CVD） during diamond films growth processes. The results show that all the depo...This paper used optical emission spectroscopy （OES） to study the gas phase in high power DC arc plasma jet chemical vapour deposition （CVD） during diamond films growth processes. The results show that all the deposition parameters （methane concentration, substrate temperature, gas flow rate and ratio of H2/Ar） could strongly influence the gas phase. C2 is found to be the most sensitive radical to deposition parameters among the radicals in gas phase. Spatially resolved OES implies that a relative high concentration of atomic H exists near the substrate surface, which is beneficial for diamond film growth. The relatively high concentrations of C2 and CH are correlated with high deposition rate of diamond. In our high deposition rate system, C2 is presumed to be the main growth radical, and CH is also believed to contribute the diamond deposition.展开更多
Self-standing CVD diamond films with different dominant crystalline surfaces are polished by the thermal-iron plate polishing method. The influence of the dominant crystalline surfaces on polishing etfficiency is inve...Self-standing CVD diamond films with different dominant crystalline surfaces are polished by the thermal-iron plate polishing method. The influence of the dominant crystalline surfaces on polishing etfficiency is investigated by measuring the removal rate and final roughness. The smallest rms roughness of 0.14 μm is measured with smallest removal rate in the films with the initial （220） dominant crystalline surface. Activation energy for the polishing is analysed by the Arrhenius relation. It is found that the values are 170kJ/mol, 222kJ/mol and 214kJ/mol for the film with three different dominant crystalline surfaces. Based on these values, the polishing cause is regarded as the graphitization-controlling process. In the experiment, we find that transformation of the dominant crystalline surfaces from （111） to （220） always appears in the polishing process when we polish the （111） dominant surface.展开更多
文摘This paper used optical emission spectroscopy （OES） to study the gas phase in high power DC arc plasma jet chemical vapour deposition （CVD） during diamond films growth processes. The results show that all the deposition parameters （methane concentration, substrate temperature, gas flow rate and ratio of H2/Ar） could strongly influence the gas phase. C2 is found to be the most sensitive radical to deposition parameters among the radicals in gas phase. Spatially resolved OES implies that a relative high concentration of atomic H exists near the substrate surface, which is beneficial for diamond film growth. The relatively high concentrations of C2 and CH are correlated with high deposition rate of diamond. In our high deposition rate system, C2 is presumed to be the main growth radical, and CH is also believed to contribute the diamond deposition.
基金Supported by the National High Technology Development Programme of China under Grant No 2002AA305508, the National Natural Science Foundation of China under Grant No 50472095, the Scientific Research Foundation （SRF） for the Returned 0verseas Chinese Scholars （R0CS）, State Education Ministry （2003-14）, the Beijing Novel Project （No 2003A13）, and the Beijing Natural Science Foundation under Grant No 2062015.
文摘Self-standing CVD diamond films with different dominant crystalline surfaces are polished by the thermal-iron plate polishing method. The influence of the dominant crystalline surfaces on polishing etfficiency is investigated by measuring the removal rate and final roughness. The smallest rms roughness of 0.14 μm is measured with smallest removal rate in the films with the initial （220） dominant crystalline surface. Activation energy for the polishing is analysed by the Arrhenius relation. It is found that the values are 170kJ/mol, 222kJ/mol and 214kJ/mol for the film with three different dominant crystalline surfaces. Based on these values, the polishing cause is regarded as the graphitization-controlling process. In the experiment, we find that transformation of the dominant crystalline surfaces from （111） to （220） always appears in the polishing process when we polish the （111） dominant surface.
