Treatment of Hydrogen Fluoride Generated from the F-gases Decomposition Processes

Abstract

The objective of this study is to obtain the optimal conditions to remove hydrogen fluoride (HF) generated from a variety of F-gas treatment processes. First, we selected Ca(OH) 2 and CaCO 3 as a reactant among the various alkali salts which have a high removal efficiency and a competitive price by forming a calcium fluoride precipitate. Additionally, various factors were investigated to improve the removal efficiency of HF. The conditions such as the settling time, agitating time and intensity, reaction temperature, and pH were considered as main factors. As a result, in the treatment process to remove HF through Ca-based alkali salts, the optimal conditions were a 120 min settling time, 30 min of agitation at 100 rpm, a pH of 4-8, and a reaction temperature of 40°C.

Non-CO2 greenhouse gas separation using advanced porous materials

“…The stability of adsorbents for recovery of SF 6 in the semiconductor industry is imperative due to the presence of corrosive byproducts like HF. 320,321 Porous aromatic frameworks (PAFs) constructed via strong C–C covalent bonds are promising in perfluorinated gas capture owing to their HF resistance. And their aromatic structure can also provide rich sites to form F⋯π interactions with perfluorinated gas.…”

HF Resistant Porous Aromatic Frameworks for Electronic Special Gases Separation

“…8 However, due to the low utilization rate (<40%) of those electronic special gases in semiconductor processing, the exhaust waste gases usually contain amount of unused feed gas accompanied by highly corrosive byproduct such as HF. 9,10 Traditional adsorbents such as zeolites, 11−13 pillared clays, 14 porous carbon, 15,16 and emerging metal−organic framework (MOFs) 17 exhibit drastic performance degradation in electronic special gases recovery due to coexist with toxic/corrosive HF in exhaust gas. 18−20 Developing HF resistant adsorbents to effectively separate, purify and recover these high value-added electronic gases can not only reduce environmental risks, but also save costs of semiconductor industry.…”

“…High-purity electronic special gases (e.g., SF 6 , NF 3 , CF 4 , Xe, Kr) are considered to be the “blood” of the electronics industry, which are widely used in semiconductor manufacturing such as etching, doping, vapor deposition processes. − For example, SF 6 , NF 3 , and CF 4 are mainly used for plasma cleaning and etching because of their unique reactive activity with silicon. − F 2 /Xe/Kr/Ar are used as semiconductor lithography laser mixing gas to produce excimer lasers . However, due to the low utilization rate (<40%) of those electronic special gases in semiconductor processing, the exhaust waste gases usually contain amount of unused feed gas accompanied by highly corrosive byproduct such as HF. , Traditional adsorbents such as zeolites, − pillared clays, porous carbon, , and emerging metal–organic framework (MOFs) exhibit drastic performance degradation in electronic special gases recovery due to coexist with toxic/corrosive HF in exhaust gas. − Developing HF resistant adsorbents to effectively separate, purify and recover these high value-added electronic gases can not only reduce environmental risks, but also save costs of semiconductor industry.…”