Warming Potential Reduction of C₄F₈Using Inductively Coupled Plasma

Perfluorocyclobutane (PFC-318, <i>c</i>-C<sub>4</sub>F<sub>8</sub>) in the global atmosphere

“…The perfluorocarbon (PFC) perfluorocyclobutane (c-C 4 F , octafluorocyclobutane,) is a very long-lived and potent greenhouse gas (GHG) regulated under the Paris Agreement of the United Nations Framework Convention on Climate Change (UNFCCC). Ravishankara et al (1993) concluded that the most important atmospheric loss process of c-C 4 F is Lyman-α photolysis resulting in an atmospheric lifetime of 3200 years. Later, Morris et al (1995) argued that if reactions of c-C 4 F 8 with electrons and positive ions in the mesosphere and aloft are irreversible, the lifetime could be reduced to 1400 years, which, on human timescales, is still essentially infinite.…”

“…Today we have stronger evidence for c-C 4 F 8 emissions from the semiconductor and microelectronics industry as it has been increasingly used since the 1990s for dry etching, chemical vapor deposition chamber cleaning and as deposition gas (Bosch process). Compared to other fluorinated gases used for these processes, more selective etching, cost reduction in plasma cleaning, easier abatement and hence potentially lower contribution to global warming have been cited as advantages of c-C 4 F 8 (e.g., Sasaki et al, 1998;Christophorou and Olthoff, 2001;Raju et al, 2003;Kokkoris et al, 2008; and references therein). However, due to efficient abatement with modern emission controls (up to 90 %), today's c-C 4 F 8 emissions from this industry could also be small (Zhihong et al, 2001).…”

Perfluorocyclobutane (PFC-318, <i>c</i>-C<sub>4</sub>F<sub>8</sub>) in the global atmosphere

“…The perfluorocarbon (PFC) perfluorocyclobutane (c-C 4 F 8 , PFC-318, octafluorocyclobutane, CAS 115-25-3) is a very long-lived and potent greenhouse gas (GHG) regulated under the Paris Agreement of the United Nations Framework Convention on Climate Change (UNFCCC). Ravishankara et al (1993) concluded that the most important atmospheric loss process of c-C 4 F 8 is Lyman-α photolysis resulting in an atmospheric lifetime of 3200 years. Later, Morris et al (1995) argued that if reactions of c-C 4 F 8 with electrons and positive ions in the mesosphere and aloft are irreversible, the lifetime could be reduced to 1400 years, which, on human timescales, is still essentially infinite.…”

“…Today we have stronger evidence for c-C 4 F 8 emissions from the semiconductor and microelectronics industry as it has been increasingly used since the 1990s for dry etching, chemical vapor deposition chamber cleaning, and as deposition gas (Bosch process). Compared to other fluorinated gases used for these processes, more selective etching, cost reduction in plasma cleaning, easier abatement, and hence potentially lower contribution to global warming have been cited as advantages of c-C 4 F 8 (e.g., Sasaki et al, 1998;Christophorou and Olthoff, 2001;Raju et al, 2003;Kokkoris et al, 2008;and references therein). However, due to efficient abatement with modern emission controls (up to 90 %), today's c-C 4 F 8 emissions from this industry could also be small (Zhihong et al, 2001).…”

CF4 Decomposition Using Low-Pressure Pulse-Modulated Radio Frequency Plasma

“…However, these methods have problems associated with a low decomposition efficiency, a high operation cost and large equipment. As a new method, the plasma method (1), (3) has been attracting attention, because it is very compact and easily adaptable to the existing equipment with a low operation cost. Recently, the applications of a nonthermal corona discharge plasma to the decomposition of hazardous pollutants such as NOx and VOC (4) - (11) have been significant.…”