采用密度泛函B3PW91方法,在6-311++g(d,p)基组水平研究了全氟气体C_2F_6与H自由基的脱氟反应机理。通过振动频率和内禀反应坐标(IRC)分析证实了各过渡态的准确性,获得了3条可能的反应通道。结果表明:C_2F_6+H→TS2→C_2F_5+HF是最佳的...采用密度泛函B3PW91方法,在6-311++g(d,p)基组水平研究了全氟气体C_2F_6与H自由基的脱氟反应机理。通过振动频率和内禀反应坐标(IRC)分析证实了各过渡态的准确性,获得了3条可能的反应通道。结果表明:C_2F_6+H→TS2→C_2F_5+HF是最佳的反应通道,生成的产物C_2F_5+HF的能量低于反应物C_2F_6+H的能量,是放热反应,该反应通道需要克服的能垒高度为130.6 k J/mol,是三条反应通道中最低的,不管从动力学还是热力学角度上分析都是最有利的。展开更多
研究表明含氟气体的性质决定了原子氟(F)的转化效率,通常在CxFy气体中x的值越大,氟(F)的转化效率也就会越高。所以C3F8(八氟丙烷)比C2F6(乙氟烷)具有更高的利用效率,更少的PFC(全氟化物)的排放。文章主要研究在以四乙氧基硅烷(TOES)为...研究表明含氟气体的性质决定了原子氟(F)的转化效率,通常在CxFy气体中x的值越大,氟(F)的转化效率也就会越高。所以C3F8(八氟丙烷)比C2F6(乙氟烷)具有更高的利用效率,更少的PFC(全氟化物)的排放。文章主要研究在以四乙氧基硅烷(TOES)为基础的离子增强化学气相沉积(Plasma Enhanced Chemical Vapor Deposition,PECVD)的清洗制程中,利用分解效率高的C3F8气体取代C2F6气体。通过实验设计(Design Of Experiment,DOE),调整腔体压力、射频(RF)功率、气体流量等参数,最终得到最优化的新清洗配方。应用到实际的量产中,有效地降低了成本,减少了PFC的排放。展开更多
The destruction of hexafluoroethane (C2F6), also known as R-116, was investigated in a nonthermal plasma reactor packed with dielectric pellets. The effects of the feed gas composition and the input power on the destr...The destruction of hexafluoroethane (C2F6), also known as R-116, was investigated in a nonthermal plasma reactor packed with dielectric pellets. The effects of the feed gas composition and the input power on the destruction of C2F6 were examined. The feed gas composition was varied by changing the oxygen content, the argon content and the initial C2F6 concentration. An increased input power led to increased C2F6 destruction as a result of promoting the electron-molecule collisions to dissociate C2F6 molecules. The addition of argon to the feed gas greatly improved the C2F6 destruction by reducing the energy losses due to vibrational excitation and dissociation of N2 molecules, while the increases in the oxygen content and the initial C2F6 concentration decreased the destruction efficiency. The byproducts including CO2, CO, COF2, CF4, SiF4, NO2, and N2O were identified, and the destruction mechanisms were elucidated, referring to these compounds. The most abundant byproduct was found to be carbonyl fluoride (COF2), indicating that it serves as an important medium to convert C2F6 into CO2. The energy requirement for the C2F6 destruction was in the range of 8.2–45.3 MJ/g, depending on the initial concentration.展开更多
文摘采用密度泛函B3PW91方法,在6-311++g(d,p)基组水平研究了全氟气体C_2F_6与H自由基的脱氟反应机理。通过振动频率和内禀反应坐标(IRC)分析证实了各过渡态的准确性,获得了3条可能的反应通道。结果表明:C_2F_6+H→TS2→C_2F_5+HF是最佳的反应通道,生成的产物C_2F_5+HF的能量低于反应物C_2F_6+H的能量,是放热反应,该反应通道需要克服的能垒高度为130.6 k J/mol,是三条反应通道中最低的,不管从动力学还是热力学角度上分析都是最有利的。
文摘研究表明含氟气体的性质决定了原子氟(F)的转化效率,通常在CxFy气体中x的值越大,氟(F)的转化效率也就会越高。所以C3F8(八氟丙烷)比C2F6(乙氟烷)具有更高的利用效率,更少的PFC(全氟化物)的排放。文章主要研究在以四乙氧基硅烷(TOES)为基础的离子增强化学气相沉积(Plasma Enhanced Chemical Vapor Deposition,PECVD)的清洗制程中,利用分解效率高的C3F8气体取代C2F6气体。通过实验设计(Design Of Experiment,DOE),调整腔体压力、射频(RF)功率、气体流量等参数,最终得到最优化的新清洗配方。应用到实际的量产中,有效地降低了成本,减少了PFC的排放。
文摘The destruction of hexafluoroethane (C2F6), also known as R-116, was investigated in a nonthermal plasma reactor packed with dielectric pellets. The effects of the feed gas composition and the input power on the destruction of C2F6 were examined. The feed gas composition was varied by changing the oxygen content, the argon content and the initial C2F6 concentration. An increased input power led to increased C2F6 destruction as a result of promoting the electron-molecule collisions to dissociate C2F6 molecules. The addition of argon to the feed gas greatly improved the C2F6 destruction by reducing the energy losses due to vibrational excitation and dissociation of N2 molecules, while the increases in the oxygen content and the initial C2F6 concentration decreased the destruction efficiency. The byproducts including CO2, CO, COF2, CF4, SiF4, NO2, and N2O were identified, and the destruction mechanisms were elucidated, referring to these compounds. The most abundant byproduct was found to be carbonyl fluoride (COF2), indicating that it serves as an important medium to convert C2F6 into CO2. The energy requirement for the C2F6 destruction was in the range of 8.2–45.3 MJ/g, depending on the initial concentration.
