Synergetic thermodynamic/kinetic separation of <scp>C<sub>3</sub>H<sub>8</sub></scp>/<scp>CH<sub>3</sub>F</scp> on carbon adsorbents for ultrapure fluoromethane electronic gas
Jiawu Huang, Junjie Peng, Xuan Wei, Shengjun Du, Cuiting Yang, Jing Xiao
Abstract
Abstract Atomic layer etching (ALE) using the environmentally friendly electronic gas fluoromethane (CH 3 F) is guided for fabricating nanoscale electronic components. The adsorptive purification of CH 3 F provide a viable direction to remove trace amounts of impurities to produce highly pure CH 3 F (>99.9999%) for the ALE process. Herein, to remove trace propane (~100 ppm) in CH 3 F, we report synergetic thermodynamic and kinetic separation of C 3 H 8 /CH 3 F over glucose‐derived carbon molecular sieve CMS‐T, (T as pyrolysis temperature). With pore size slightly larger than the kinetic diameter of C 3 H 8 , CMS‐600 allows both strong confined adsorption of C 3 H 8 and a higher diffusion rate of C 3 H 8 over CH 3 F, resulting in a remarkable separation factor of 51.1. Breakthrough experiment demonstrates a high dynamic production capacity of 457 L kg −1 of 7 N CH 3 F (<100 ppb of C 3 H 8 ) over CMS‐600 with excellent cycling stability. Adsorption purification over carbon provides a feasible approach for industrial hyperpurification of electronic gas.