초록 ▼

A method of processing semiconductor manufacturing exhaust gases for recovering at least hexafluoroethane in which a feed stream composed of the exhaust gases is passed through an adsorbent bed selected to adsorb oxygen, and also nitrogen if present, but not to appreciably adsorb the hexafluoroethan

A method of processing semiconductor manufacturing exhaust gases for recovering at least hexafluoroethane in which a feed stream composed of the exhaust gases is passed through an adsorbent bed selected to adsorb oxygen, and also nitrogen if present, but not to appreciably adsorb the hexafluoroethane. As a result, a product stream, discharged from the adsorbent bed, has a higher concentration of hexafluoroethane than in the feed stream. In one embodiment, only a single adsorbent such as carbon molecular sieve is provided to adsorb the oxygen or a modified 4A zeolite could be used to adsorb both oxygen and nitrogen. When nitrogen is a potential constituent, layers of carbon molecular sieve and zeolite are provided to adsorb the oxygen and then the nitrogen, respectively. A third adsorbent, preferably 5A zeolite may be provided in addition to the foregoing two adsorbents to also adsorb any carbon tetrafluoride produced as a by-product.

대표청구항 ▼

[ What is claimed is:] [1.] A method of processing semiconductor manufacturing exhaust gases for recovering at least hexafluoroethane, said method comprising:introducing a feed stream originating from a semiconductor processing chamber to an adsorbent bed, said feed stream made-up of said semiconduc

[ What is claimed is:] [1.] A method of processing semiconductor manufacturing exhaust gases for recovering at least hexafluoroethane, said method comprising:introducing a feed stream originating from a semiconductor processing chamber to an adsorbent bed, said feed stream made-up of said semiconductor manufacturing exhaust gases and comprising oxygen, nitrogen, and said hexafluoroethane; anddischarging a product stream from said adsorbent bed;the adsorbent bed containing at least a first adsorbent selected to adsorb at least said oxygen and said nitrogen and to substantially not adsorb said hexafluoroethane such that said product stream has a higher concentration of said hexafluoroethane than said feed stream.