碳—氢—氯体系金刚石薄膜生长条件预测

PREDICTION OF GROWTH CONDITIONS FOR DIAMOND FILM IN CARBON-HYDROGEN-CHLORINE SYSTEM

首次计算了碳—氢—氯体系中生长金刚石薄膜的相图，研究了该体系中金刚石生长区随衬底温度及氯含量变化的趋势，与实验结果符合较好计算结果表明，C—H—Cl系相图中金刚石生长区被限制在两个小三角形（CH4—H—HCl和CCh—HCl—Cl）中变化．可能生长金刚石薄膜的碳氢纪组分被严格地限制在金刚石生长区内，并随生长温度和压力等条件而变化．当气相中氯含量与氢的含量相近时，金刚石生长区趋于消失金刚石生长区为实验提供了选择和优化碳氢级组分、生长温度及压力的理论依据．

Ternary phase diagrams for diamond film synthesis in carbon-hydrogen-chlorine (C-H-Cl) system are first calculated. The change trend of diamond growth region with substrate temperature and chlorine addition is studied. Our theoretical calculations agree well with experimental results. The calculating results reveal that the diamond growth region of the ternary phase diagram in C-H-Cl system is confined to the two small triangles (CH4-H-HCl and CCl4-HCl-Cl). The composition which may lead to diamond deposition is severely confined to the diamond growth region and changes with the growth condition such as substrate temperature and total pressure. The diamond growth region vanishes when the amount of chorine is nearly equal to that of hydrogen in gas phase.Diamond growth region allows selection and optimization of the experimental growth conditions suchas composition, temperature and pressure.