WO2022127019A1 - 一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法 - Google Patents

一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法 Download PDF

Info

Publication number
WO2022127019A1
WO2022127019A1 PCT/CN2021/094254 CN2021094254W WO2022127019A1 WO 2022127019 A1 WO2022127019 A1 WO 2022127019A1 CN 2021094254 W CN2021094254 W CN 2021094254W WO 2022127019 A1 WO2022127019 A1 WO 2022127019A1
Authority
WO
WIPO (PCT)
Prior art keywords
gas
hcl
adsorption
tower
rectification
Prior art date
Application number
PCT/CN2021/094254
Other languages
English (en)
French (fr)
Inventor
钟娅玲
汪兰海
钟雨明
Original Assignee
浙江天采云集科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 浙江天采云集科技股份有限公司 filed Critical 浙江天采云集科技股份有限公司
Priority to JP2022512788A priority Critical patent/JP7541763B2/ja
Publication of WO2022127019A1 publication Critical patent/WO2022127019A1/zh

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B7/00—Halogens; Halogen acids
    • C01B7/01—Chlorine; Hydrogen chloride
    • C01B7/07—Purification ; Separation
    • C01B7/0706—Purification ; Separation of hydrogen chloride
    • C01B7/0712—Purification ; Separation of hydrogen chloride by distillation
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
    • C01B3/50—Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification
    • C01B3/56—Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification by contacting with solids; Regeneration of used solids
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B7/00—Halogens; Halogen acids
    • C01B7/01—Chlorine; Hydrogen chloride
    • C01B7/07—Purification ; Separation
    • C01B7/0706—Purification ; Separation of hydrogen chloride
    • C01B7/0718—Purification ; Separation of hydrogen chloride by adsorption
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B7/00—Halogens; Halogen acids
    • C01B7/19—Fluorine; Hydrogen fluoride
    • C01B7/191—Hydrogen fluoride
    • C01B7/195—Separation; Purification
    • C01B7/196—Separation; Purification by distillation
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B7/00—Halogens; Halogen acids
    • C01B7/19—Fluorine; Hydrogen fluoride
    • C01B7/191—Hydrogen fluoride
    • C01B7/195—Separation; Purification
    • C01B7/197—Separation; Purification by adsorption

Definitions

  • the invention relates to the field of environmental protection of effective component recovery and recycling of etching tail gas in a semiconductor manufacturing process, and more particularly to a method for separating, recycling and recycling FTrPSA (full temperature range pressure swing adsorption) of etching tail gas containing HF/HCl .
  • FTrPSA full temperature range pressure swing adsorption
  • Etching on silicon-based (Si) or silicon carbide (SiC)-based wafers or epitaxial films is the most important step in chip manufacturing such as semiconductor integrated circuits (ICs).
  • ICs semiconductor integrated circuits
  • fluorine (F), chlorine-containing Plasma or conventional gas dry etching of (Cl) compounds is widely used in the semiconductor industry; for example, the production of usually integrated circuits (ICs) involves steps such as deposition, masking, etching and stripping in order to form and Connect circuit components like transistors, resistors, and capacitors.
  • Etching technology processing methods and devices such as reactive ion etching (RIE), electron cyclotron resonance (ECR), helical wave source (HWS) and inductively coupled plasma source (ICP), which have appeared successively, are adapted to the requirements of this high-resolution integrated circuit. And generated, such as the etching area is greater than 300mm, the etching line width is less than 0.1 ⁇ m and so on.
  • RIE reactive ion etching
  • ECR electron cyclotron resonance
  • HWS helical wave source
  • ICP inductively coupled plasma source
  • Etching is the process of selectively removing unwanted material from the surface of a silicon- or silicon-carbide-based wafer or epitaxial thin film ("wafer" for short), on a glue-coated wafer Duplicate mask graphics correctly.
  • Etching can also be divided into wet and dry methods. Among them, plasma etching in dry etching has become the main etching process.
  • the gases commonly used in dry etching are mainly fluorine-based gases and the introduction of Cl and Br-based mixed gases, such as hydrogen fluoride (HF), hydrogen chloride (HCl), carbon tetrafluoride (CF 4 ), sulfur hexafluoride (SF 6 ), nitrogen trifluoride (NF 3 ), carbon tetrachloride (CCl 4 ), etc., while hydrogen ( H 2 ), argon (Ar), oxygen (O 2 ), nitrogen (N 2 ), etc. are used as carrier gases to react with Si or SiC on the wafer surface in a low-pressure discharge plasma environment to generate HF in the gas phase.
  • HF hydrogen fluoride
  • HCl hydrogen chloride
  • CF 4 carbon tetrafluoride
  • SF 6 sulfur hexafluoride
  • NF 3 nitrogen trifluoride
  • CCl 4 carbon tetrachloride
  • the etching tail gas has the characteristics of flammable, explosive, toxic and corrosive dangerous chemical gas.
  • the treatment method should not only meet the atmospheric emission standards, but also be effective in technology and economy, and reduce production costs.
  • etching tail gas There are five main methods for industrially treating etching tail gas: water washing, acid-base neutralization, oxidative combustion, adsorption and plasma combustion.
  • the water washing method is aimed at the working conditions where the etching tail gas mainly contains extremely acidic and toxic impurities.
  • the acid components are absorbed to form liquids and the toxic impurities components are converted into non-toxic substances or precipitation (water slurry). emission.
  • this method is simple and easy to operate and widely used in industry, due to the limitation of absorption phase balance and conversion efficiency, and the extremely strong corrosiveness of the formed absorption liquid, many acidic impurity components still remain in the exhaust gas after absorption. It is difficult to fully meet the emission standards, and must be further diluted with air or treated by other methods such as combustion or adsorption, in order to meet the emission standards.
  • the water washing method can also use heated water vapor, which is more conducive to the conversion of harmful impurities into harmless oxides at higher temperatures, so that the purification efficiency of the water washing method becomes higher.
  • the main problem of the water washing method is that it consumes a lot of water, and produces secondary pollutants such as hydrofluoric acid, hydrochloric acid or fluorosilicic acid that are difficult to recover and are highly corrosive, resulting in a large investment in treatment equipment; at the same time, the water washing method forms Some high-fluorine or high-chlorine silicic acid and silicon or silica particle dust are easy to form slurry and block valves or pipes and other equipment, and decompose and corrode equipment under heat, resulting in leakage and other hazards; It has a certain effect in the working conditions that contain more water-soluble harmful impurity components or are prone to conversion reactions with water vapor.
  • the acid-base neutralization method is aimed at the acidic characteristics of the etching tail gas.
  • an alkaline solution such as calcium hydroxide
  • the fluoride ion or HF in it is formed into calcium fluoride (CaF 2 , namely artificial fluorite) or high fluorine/high Calcium chlorosilicate is removed by precipitation or slurry, and the unabsorbed gas is added to other alkaline solutions to further remove the acidic impurities, so that the residual acidic impurities in the tail gas meet the emission standards.
  • the well-known British company EDWARDS invented a chemical neutralization method and device - gas reactor column (GRC, gasreactorcolumn), the principle of which is to use chemical neutralization method to treat exhaust gas; the device
  • the column tube is filled with an appropriate mixture of inorganic small particles.
  • the tail gas undergoes a neutralization reaction through the column tube.
  • the gas reactor column is a dry chemical reaction, which can be directly connected to the vacuum system. Connected, the exhaust gas undergoes a sufficient chemical reaction through the alkaline or metal alkaline substances in the column tube, some are converted into inert substances, and some are adsorbed by the chemical reaction, which greatly reduces the harmful exhaust gas discharged.
  • the replacement frequency of the gas column is relatively high, and sometimes there is incomplete adsorption or penetration of harmful components caused by the deactivation of the reaction column, resulting in secondary pollution.
  • the acid-base neutralization method or chemical neutralization method is still limited by the equilibrium of absorption or chemical adsorption. To completely make the exhaust emission meet the standard, multi-stage or multi-column neutralization reactions are required, and the cost is relatively high.
  • the oxidative combustion method utilizes the flammability of etching exhaust gas containing more flammable components, such as H 2 , silane, silicon tetrafluoride, and organic matter (VOC), etc., under sufficient temperature and time, pass air Or the oxygen-containing compound gas is incinerated in contact with flammable components, so that oxides can be generated, and then the oxidized product is cooled by heat exchange until it is condensed and discharged, and the remaining residual gas is washed with an alkaline solution to remove the acid in the exhaust gas. .
  • flammable components such as H 2 , silane, silicon tetrafluoride, and organic matter (VOC), etc.
  • the etching tail gas contains more non-flammable HF, HCl and other acid gases, this method is not suitable for processing the etching tail gas, especially the tail gas contains specific photoresist, such as polymethyl methyl (PMMA), etc., generally It is difficult to be cleaned in the cleaning process, and a small amount of photoresist remaining in the etching exhaust gas cannot be treated by burning (it will form dioxins or oxazoles), and other physical methods can only be used. At present, the oxidative combustion method is only suitable for the treatment of exhaust gas produced in some chemical vapor deposition (CVD).
  • CVD chemical vapor deposition
  • the adsorption method is to achieve selective separation and purification according to the physical or chemical adsorption force between the etching tail gas components and the selected specific adsorbent; commonly used aluminum oxide, activated carbon or molecular sieves are highly polar HF. , HCl, H 2 O, SiF 4 , SiH 4 , CO 2 and VOC have obvious adsorption effect. However, due to the strong adsorption force, the regeneration of the adsorbent will be quite difficult, the service life will be short and the cost will rise. It is worth noting that the adsorbents used for the adsorption of HF are relatively special. Most of these adsorbents are fluorides of alkaline metals.
  • the chemical reaction between metal fluorides and HF at lower temperatures is used to selectively carry out chemical adsorption, forming
  • the metal fluoride-HF complex is decomposed at a higher temperature, so as to realize the desorption of HF from the adsorbent, and other impurities have no selectivity on the adsorbent, thus realizing the desorption of HF. Separation and purification.
  • the applicable working conditions of this chemical adsorption method are mostly fluorination reaction to prepare chlorofluoroalkanes (CFC), hydrochlorofluoroalkanes (HCFC), hydrofluoroalkanes (HFC), sulfuryl fluoride (SO 2 F 2 ), etc.
  • the selective adsorption, separation and recovery of HF by the reaction mixture produced by the reaction is relatively good, but the loss rate of the adsorbent is large.
  • the adsorbent will also undergo chemical reaction or co-adsorption phenomenon with impurity components such as water, resulting in pulverization or supersaturated adsorption of the adsorbent, which cannot be effectively treated and Purification; in addition, selective adsorption using metal getter or membrane separation system is more effective for the removal of some impurities, but the effect on etching tail gas is not obvious and the cost is high.
  • One of the biggest problems of the adsorption method is that it is more suitable for the low concentration of adsorbate (impurity) components in the etching tail gas. Increase, the operating cost also increases, the desorption effect is poor.
  • Plasma purification method is currently a popular treatment method, especially for fluorinated exhaust gas, including etching exhaust gas, hydrogen fluoride preparation exhaust gas and other HF-containing exhaust gas.
  • Plasma purification is the use of plasma-enhanced decomposition (destruction) to directly transform harmful components. This transformation is completed in a high-density plasma region obtained by glow discharge or other discharge forms. There are a large number of active particles in the etchant, and these particles can destroy the toxic and refractory substances in the etching exhaust.
  • this method is a very promising exhaust gas treatment method, such as pulsed corona plasma chemical treatment (PPCP, pulsed corona Induced plasma) for nitrogen oxides (NO X ), sulfur dioxide (SO 2 ), Mercury (Hg) vapor and volatile organic compounds (VOCs) have better treatment effect.
  • PPCP pulsed corona plasma chemical treatment
  • NO X nitrogen oxides
  • SO 2 sulfur dioxide
  • SO 2 sulfur dioxide
  • Hg Mercury
  • VOCs volatile organic compounds
  • the removal of NO X and SO 2 is the oxidation reaction of strong free radicals generated by pulsed corona with them, and in the presence of additives such as ammonia (NH 3 ) and H 2 O, it is converted into sulfuric acid Salts and nitrates; VOCs are removed by the excitation, decomposition and ionization of high-energy electrons generated by pulsed corona, and finally CO 2 and CO with simple structure are generated; for fluorinated exhaust gas, hydrogen or hydrogen-containing compounds are added to Such as H 2 , NH 3 or methane (CH 4 ), under plasma conditions, components such as fluorides that are difficult to dissolve in water or difficult to decompose are decomposed, and the generated hydrogen ions (H+) and fluoride ions (F-) or chlorine ions are decomposed.
  • additives such as ammonia (NH 3 ) and H 2 O
  • VOCs are removed by the excitation, decomposition and ionization of high-energy electrons generated by pulsed cor
  • the ions (Cl+) form HF and HCl, which are then washed with water to purify the fluorinated tail gas.
  • the plasma treatment effect of etching tail gas with relatively high content of HF, HCl, etc. is general, and the cost is expensive, so it is only suitable for small-scale tail gas treatment.
  • the object of the present invention is to: provide a kind of HF/HCl etching tail gas FTrPSA (full temperature range pressure swing adsorption) separation and recovery recycling method, and obtain high - purity HF from the dry etching tail gas containing HF/HCl/H , HCl or H 2 and return to the etching process for recycling.
  • FTrPSA full temperature range pressure swing adsorption
  • Full temperature range pressure swing adsorption (full name: Full Temperature Range-Pressure Swing Adsorption, referred to as: FTrPSA) is a method based on pressure swing adsorption (PSA) and can be coupled with various separation technologies. The difference in the absorption/adsorption/rectification and physical and chemical properties of each component (HF/HCl is the effective component, and the rest are impurity components) at different pressures and temperatures.
  • the main and spray absorption, HF rectification/HCl refining (rectification) and condensation are coupled, so that the adsorption and desorption are easy to match and balance the cycle operation in the medium temperature pressure swing adsorption process for separation and purification, so as to achieve HF/HCl recovery and Return to the etching process for recycling.
  • the technical scheme adopted in the present invention is: a method for separating and recycling FTrPSA containing HF/HCl etching tail gas.
  • H 2 Hydrogen
  • active components hydrogen fluoride (HF) and hydrogen chloride (HCl)
  • HCl hydrogen chloride
  • H 2 O water
  • SiF 4 silicon tetrafluoride
  • SiCl 4 silicon tetrachloride
  • silane SiH 4
  • methane CH 4
  • CO carbon dioxide
  • VOCs volatile organic compounds
  • Me+ metal ions
  • fine solids and aerosol particles Part of the impurity components of high fluorosilicic acid/high chlorosilane, the temperature is normal temperature (20-25 °C), and the pressure is normal pressure or slightly positive pressure.
  • Pretreatment control the temperature of the raw material gas to be normal temperature (20-25°C) and the pressure to be 0.2-0.3MPa, and send it to the pretreatment unit to remove dust, particles, oil mist, VOCs, high fluorosilane/acid and High chlorosilane, the purified raw gas formed by pretreatment enters the chlorosilane/HCl spray absorption process, wherein the pretreatment unit includes a dust collector, a particle removal filter, a degreasing mist trap and an activated carbon adsorber;
  • Chlorosilane/HCl spray absorption the chlorosilane/HCl spray absorption process adopts the spray absorption tower of chlorosilane and HCl mixed liquid as the absorbent as the reactor, and the purified raw gas from the pretreatment process is subjected to cold and heat exchange After reaching 50 ⁇ 80°C, it enters from the bottom of the spray absorption tower and conducts reverse mass transfer exchange with the absorbent, wherein the absorption liquid enriched with chlorosilane/HCl flows out from the bottom of the spray absorption tower, and enters the subsequent multi-stage evaporation/ Compression/condensation process, meanwhile, the output of a small amount of residual particles, high-chlorosilane, high-fluorosilane/acid impurities from the bottom of the tower is processed for environmental protection, and the non-condensable gas enriched with HF and low-boiling point components flows out from the top of the spray absorption tower 1 , enter the medium temperature pressure swing adsorption process;
  • the medium temperature pressure swing adsorption process is composed of two stages of pressure swing adsorption, each stage of pressure swing adsorption is composed of more than 2 adsorption towers, and at least one adsorption tower is in the adsorption step, and the rest of the adsorption towers are in the desorption process.
  • the non-condensable gas 1 from the chlorosilane/HCl spray absorption process enters from the bottom of the first-stage PSA (1#PSA) adsorption tower, and the operating pressure of 1#PSA is 0.2 ⁇ 0.3MPa, and the operating temperature is 50 ⁇ 80 °C, Among them, the non-adsorption phase gas flowing out from the top of the adsorption tower in the adsorption step is crude HF gas, and the condensed non-condensable gas 2 is subjected to precision filtration and deionized water absorption to obtain an HF aqueous solution with a concentration of 40%.
  • the non-condensable gas 3 formed after water absorption is output as a hydrogen-rich gas, or used as a fuel gas, or as a raw material gas for pressure swing adsorption hydrogen extraction, and the crude HF liquid formed after condensation is finely filtered to enter the next process.
  • HF rectification the desorption gas flowing out from the bottom of the 1#PSA adsorption tower in the desorption step enters from the bottom of the adsorption tower of the second stage PSA (2#PSA) after pressurization and cold and heat exchange, and the 2#PSA adsorption
  • the operating pressure of the tower is 0.2 to 0.3 MPa, and the operating temperature is 50 to 80 °C.
  • the non-adsorption phase intermediate gas flowing out from the top of the 2#PSA adsorption tower in the adsorption step is different from the non-adsorption phase from the chlorosilane/HCl spray absorption process.
  • the condensed gas 1 is mixed and returned to the 1#PSA adsorption tower, and the effective components HF and HCl are further recovered, and the desorbed gas flowing out from the bottom of the 2#PSA adsorption tower is concentrated gas, which is returned to the chlorosilane/HCl spray absorption process for further recovery. active ingredient;
  • the HF rectification process comprises a rectifying tower formed by two upper and lower sections of rectification, and the rectified HF liquid obtained after the condensation of the thick HF gas from the medium temperature pressure swing adsorption process enters the rectification in the HF rectification process Tower, the rectified HF liquid enters from the top of the lower rectification tower or from the bottom of the upper rectification tower, wherein, the light component impurity gas distilled from the top of the upper rectification tower is returned to the subsequent tail gas absorption process, from the upper rectification tower.
  • the non-condensable gas 4 formed at the bottom of the distillation column or the top distillate from the lower section of the distillation column after condensation is anhydrous HF (AHF) gas, the purity is greater than or equal to 99.99%, directly used as electronic grade HF product gas, returned to dry It is recycled in the etching process.
  • AHF hydrous HF
  • the liquid formed after condensation is used as the reflux of the upper or lower rectification, and the bottoms liquid containing a small amount of heavy component impurity components distilled from the bottom of the lower rectification is formed after condensation.
  • the non-condensable gas 5 a part enters the multi-stage evaporation/compression/condensation process, and the other part enters the tail gas absorption process, and the liquid formed after the condensation returns to the chlorosilane/HCl spray absorption process as an absorbent and is recycled;
  • the absorption liquid from chlorosilane/HCl spray absorption process enters multi-stage evaporation, then enters condenser, therefrom obtains the thick HCl gas of gas phase and the bottom of heavy component tower from HF rectification process
  • the non-condensable gas 5 obtained after the fluid is condensed is mixed, and the thick HCl liquid formed after the condensation enters the HCl refining process, and the crude chlorosilane liquid flows out from the condenser, and enters the subsequent shallow cooling rectification process in the chlorosilane.
  • the non-condensable gas 6 flowing out of the condenser is returned to the medium temperature pressure swing adsorption process after the cold and heat exchange, and the effective components HF and HCl are further recovered;
  • the HCl refining process includes a HCl rectifying column and a vacuum rectifying column, the operating pressure of the HCl rectifying column is 0.3 ⁇ 0.6MPa, the operating temperature is 50 ⁇ 80 °C, and the operating pressure of the vacuum rectifying column is -0.08 ⁇ -0.1MPa, the operating temperature is 60 ⁇ 120°C, among which, the HCl product gas with a purity of more than 99.99% flows out from the top of the HCl rectification tower, a part is returned to the dry etching process for recycling, and the other part is liquefied as chlorosilane/
  • the absorbent of the HCl spray absorption process is recycled, and the effluent from the bottom of the HCl rectification column enters the vacuum rectification column, and the top gas flowing out from the top of the vacuum rectification column is a non-condensable gas 7, and a part enters the subsequent tail gas absorption process,
  • the other part is returned to the medium temperature pressure swing
  • the step of shallow cooling rectification in chlorosilane includes a rectifying column, a crude chlorosilane liquid from a multi-stage evaporation/compression/condensation process, and/or a vacuum column bottom from the HCl refining process
  • the shallow cooling rectification process in the chlorosilane that the heavy component fluid enters, the operating temperature is -35 ⁇ 10 °C, and the operating pressure is 0.6 ⁇ 2.0MPa, wherein, the non-condensable gas 8 flowing out from the top of the rectifying tower is cooled and heated After the exchange, it is returned to the medium temperature pressure swing adsorption process, and the chlorosilane liquid flows out from the bottom of the rectifying tower.
  • a part of it is mixed with HCl to form a mixed solution and returned to the chlorosilane/HCl spray absorption process as an absorbent for recycling, and the other part is mixed with sulfuric acid. Used as an absorbent in the exhaust gas
  • the tail gas absorption process adopts the tail gas absorption tower as the reactor of the chlorosilane liquid and the fresh sulfuric acid mixed solution from the shallow cooling rectification process in the chlorosilane as the absorbent, and the upper stage rectification tower from the HF rectification process
  • the light component impurity gas distilled from the top, the heavy components from the bottom of the lower stage rectification column of the HF rectification process, and the condensed non-condensable gas 5 and the non-condensable gas 7 from the HCl refining process are mixed and then enter the tail gas absorption tower.
  • the fluorosilicic acid solution is formed from the bottom of the absorption tower, and the raw material liquid of the AHF production process prepared by the defluorosilicic acid method is output as a raw material for recycling, and the non-condensable gas 9 flowing out from the top of the absorption tower is directly discharged as an exhaust gas.
  • the purified raw material gas directly enters the medium temperature pressure swing adsorption process, and the crude HF gas flowing out from the top of the 1# PSA tower is not condensed after condensation.
  • Gas 2 the HF aqueous solution with a concentration of 40% is obtained by precision filtration and deionized water absorption, and the non-condensable gas 3 formed after water absorption is output as hydrogen-rich gas, or used as fuel gas, or as pressure swing adsorption.
  • the raw gas of hydrogen, and the crude HF liquid formed by condensation enter HF rectification after precision filtration.
  • the bottom of the adsorption tower of the second stage PSA (2#PSA) enters, and the non-adsorption phase intermediate gas flowing out from the top of the 2#PSA adsorption tower in the adsorption step is directly returned to the 1#PSA adsorption tower to further recover the effective components, while
  • the desorbed gas flowing out from the bottom of the 2#PSA adsorption tower is concentrated gas, and the non-condensable gas 1 formed by the newly installed condenser is mixed with the crude HF gas of the medium temperature pressure swing adsorption process to recover the effective component HF , and the liquid formed from the newly installed condenser directly enters the HCl refining process to recover HCl, wherein the heavy components flowing out from the HCl refining process are directly discharged after treatment, thus eliminating the need for chlorosilane/HCl spraying Absorption, multi-stage evaporation/compression/condensation and rectification of medium-shallow chlorosilane.
  • the purified raw material gas from the pretreatment process enters the chlorosilane/HCl spray absorption process after being exchanged with cold and heat to 80-160 °C, and is sprayed from the top of the absorption tower.
  • the outflowing non-condensable gas 1 and the non-condensable gas 2 formed after condensation enter the medium-temperature pressure swing adsorption process composed of two-stage PSA, and the condensed liquid formed after condensation directly enters the HCl refining process, from the spray absorption tower.
  • the absorbing liquid flowing out from the bottom enters the multi-stage evaporation/compression/condensation process.
  • the purified raw material gas from the pretreatment process enters the chlorosilane/HCl spray absorption process after being exchanged with cold and heat to 80-160° C.
  • the operating pressure of 1#PSA is 0.2 ⁇ 0.3MPa, and the operating temperature is 50 ⁇ 80°C.
  • the non-adsorption phase gas flowing out from the top of the adsorption tower in the adsorption step is the intermediate gas and enters the second stage (2#PSA) for adsorption
  • the non-adsorbed phase gas flowing out from the top of the adsorption tower in the adsorption step is crude HF gas, and the condensed non-condensable gas 3 is subjected to precision filtration and deionized water absorption to obtain a concentration of 40% HF aqueous solution for export.
  • the non-condensable gas 4 formed by water absorption is output as hydrogen-rich gas, or used as fuel gas, or as the raw material gas for pressure swing adsorption hydrogen extraction, and the crude HF liquid formed after condensation, after precision filtration, enters HF
  • the stripping gas flowing out from the bottom of the 1#PSA adsorption tower in the desorption step and the concentrated gas flowing out from the bottom of the 2#PSA adsorption tower are respectively returned to the chlorosilane/HCl spray absorption process to further recover the effective components, without
  • the condensed liquid formed by the condensation of the condensed gas 1 directly enters the HCl refining process, and the absorption liquid flowing out from the bottom of the spray absorption tower enters the multi-stage evaporation/compression/condensation process.
  • the purified raw material gas obtained from the raw material gas through the pretreatment process directly enters the medium temperature pressure swing adsorption process composed of a section of PSA, wherein a section of PSA is composed of 2.
  • adsorption tower It consists of more than one adsorption tower, one adsorption tower is in the adsorption step, and the other adsorption towers are in the desorption step including different stages of decompression and reverse discharge or vacuuming, boosting or final charging, and the operating pressure of the adsorption tower is 0.2 ⁇ 0.3MPa , the operating temperature is 70-90 °C, the purified raw gas enters from the bottom of the PSA adsorption tower, and the non-adsorption phase gas flowing out from the top of the adsorption tower in the adsorption step is adsorption waste gas, which is used as fuel gas, or as pressure swing adsorption for hydrogen extraction.
  • the outflowing heavy component fluid is directly purified by HCl, thereby obtaining HCl product gas, which is returned to the dry etching process for recycling, thus eliminating the need for chlorosilane/HCl spray absorption, multi-stage evaporation/compression/condensation, medium-shallow Cold chlorosilane rectification process, this working condition is also suitable for the separation and recycling of low-concentration HF/HCl acidic exhaust gas after etching tail gas treated by traditional water-washing absorption method.
  • Acid export treatment the washed non-condensable gas 2 is used as fuel gas or as the raw material gas for pressure swing adsorption hydrogen extraction, and the condensate formed after condensation enters the HF rectification process, and the non-condensable gas flows out from the HF rectification process.
  • the HF product gas flowing out from the HF rectification process is returned to the dry etching process for recycling, and the heavy component fluid flowing out from the bottom of the HF rectification tower is directly purified by HCl to obtain HCl products
  • the gas is returned to the dry etching process for recycling, thus eliminating the need for chlorosilane/HCl spray absorption, multi-stage evaporation/compression/condensation, medium-shallow chlorosilane rectification and medium-temperature pressure swing adsorption processes. It is suitable for the separation and recycling of high-concentration HF/HCl generated after plasma cleaning.
  • the raw material gas for pressure swing adsorption and hydrogen extraction is the non-condensable gas or adsorption waste gas generated after washing, wherein the non-condensable gas or adsorption waste gas first enters the drying tower to remove the moisture therein.
  • the present invention realizes the separation and recovery of HF and HCl from the HF/HCl-containing dry etching tail gas, and returns to the etching process for recycling, which greatly reduces the cost of etching gas raw materials and the cost of environmental protection treatment of tail gas, and solves the problem of existing
  • the technology only meets the standard emission and cannot realize the comprehensive utilization of exhaust gas, which fills the gap in this technical field;
  • the present invention utilizes the difference in adsorption/absorption/rectification and condensation coefficients and physical and chemical properties of each component in the raw gas (HF/HCl is an effective component, and the rest are impurity components) at different pressures and temperatures.
  • the two-stage medium temperature pressure swing adsorption process is mainly combined with chlorosilane spray absorption, HF rectification, HCl refining (rectification), chlorosilane rectification and evaporation/compression/condensation.
  • the adsorption and desorption are easy to match and balance the cycle operation for separation and purification, so as to realize the separation and purification of HF/HCl and other impurity components, and return to the dry etching process for recycling;
  • the present invention overcomes the existing chemical adsorption method due to HF and adsorbent at low temperature chemical (Ao combination) reaction to carry out adsorption and decomposition reaction at high temperature to carry out desorption caused by the adsorption and desorption frequent cycle operation process.
  • the high loss rate of the adsorbent and the chemical reaction of the adsorbent with impurity components such as water will lead to serious pulverization and failure of the adsorbent, so that the adsorption and separation cannot be effectively carried out. It is easy to use the two polarities of HF and HCl for adsorption.
  • the present invention can effectively simplify the process under different raw material gas working conditions, and realize the recycling and reuse of HF/HCl, thus, the etching tail gas can be treated with the traditional water washing method or plasma method for the purpose of environmental protection, It will effectively recover HF/HCl and return it to the etching process or dry cleaning process for recycling, which solves the defect that the traditional treatment method cannot be recycled, and also meets the emission requirements;
  • the present invention can recover HF/HCl from the etching tail gas for recycling and reuse, and can also obtain valuable electronic-grade H2 products by adding PSA for hydrogen extraction, and can return to the dry etching process for recycling, or as a The source of hydrogen used in other semiconductor processes.
  • the process carrier gas is argon or nitrogen or mixed with hydrogen
  • electronic-grade argon can be obtained by adjusting PSA for hydrogen extraction or argon or nitrogen extraction, or by adding low-temperature adsorption. Nitrogen and other products.
  • Embodiment 1 is a schematic flowchart of Embodiment 1 of the present invention.
  • Embodiment 2 is a schematic flow chart of Embodiment 2 of the present invention.
  • Embodiment 3 is a schematic flowchart of Embodiment 3 of the present invention.
  • Embodiment 4 is a schematic flow chart of Embodiment 4 of the present invention.
  • Embodiment 5 is a schematic flowchart of Embodiment 5 of the present invention.
  • Embodiment 6 is a schematic flowchart of Embodiment 6 of the present invention.
  • FIG. 7 is a schematic flowchart of Embodiment 7 of the present invention.
  • normal temperature refers to 20-25 °C
  • normal pressure is one atmosphere.
  • a method for separating and recycling FTrPSA containing HF/HCl etching tail gas 83% (v/v), effective components hydrogen fluoride (HF) 9% and hydrogen chloride (HCl) 5%, and a small amount of water (H 2 O), silicon tetrafluoride (SiF 4 ), silicon tetrachloride ( SiCl 4 ), silane (SiH 4 ), methane (CH 4 ), carbon monoxide (CO), carbon dioxide (CO 2 ), and trace or trace amounts of volatile organic compounds (VOCs), metal ions (Me+), fine solids and gases Sol particles (SS), some impurity components of perfluorosilicic acid/perchlorosilane, normal temperature and pressure.
  • the feed gas is pressurized and then sent to a pretreatment unit consisting of a dust collector, a particle removal filter, a degreasing mist trap and an activated carbon adsorber, under the operating conditions of 0.2-0.3MPa pressure and normal temperature
  • a pretreatment unit consisting of a dust collector, a particle removal filter, a degreasing mist trap and an activated carbon adsorber, under the operating conditions of 0.2-0.3MPa pressure and normal temperature
  • dust, particles (SS), oil mist, VOCs, high fluorosilane/acid and high chlorosilane are successively removed, and the formed purified raw gas enters the next process—chlorosilane/HCl spray absorption;
  • Chlorosilane/HCl spray absorption the purified raw material gas from the pretreatment process, after cold and heat exchange to 50 ⁇ 80 °C, enters from the bottom of the spray absorption tower, using chlorosilane and HCl (1:1 ⁇ 1.4 )
  • the mixed liquid is used as an absorbent, and it is sprayed down from the top of the spray absorption tower to carry out reverse mass transfer exchange with the purified raw material gas, and the absorption liquid enriched with chlorosilane/HCl flows out from the bottom of the spray absorption tower, and enters the subsequent multi-stage evaporation.
  • the output of a small amount of residual particles, high-chlorosilane, high-fluorosilane/acid impurities from the bottom of the tower is processed for environmental protection, and the non-condensable gas enriched with HF and low-boiling point components flows out from the top of the spray absorption tower 1. Go directly to the next process—medium temperature pressure swing adsorption;
  • the non-condensable gas 1 from the chlorosilane/HCl spray absorption process enters the medium temperature pressure swing adsorption process composed of two stages of pressure swing adsorption (PSA), and the first and second stages of pressure swing adsorption (1#PSA, 2#PSA) are composed of 3 adsorption towers, 1 adsorption tower is in the adsorption step, and the other 2 adsorption towers are in different stages of desorption including decompression and reverse discharge or vacuuming, boosting or final charging Step
  • the non-condensable gas 1 enters from the bottom of 1#PSA adsorption tower, the operating pressure of 1#PSA is 0.2 ⁇ 0.3MPa, the operating temperature is 50 ⁇ 80°C, and the non-adsorption phase gas flowing out from the top of the adsorption tower in the adsorption step is: Crude HF gas, the condensed non-condensable gas 2, the HF aqueous solution with a concentration
  • the operating pressure of the 2#PSA adsorption tower is 0.2 ⁇ 0.3MPa, and the operating temperature is 50 ⁇ 80°C, and flows out from the top of the 2#PSA adsorption tower in the adsorption step.
  • the intermediate gas of the non-adsorption phase is mixed with the non-condensable gas 1 from the chlorosilane/HCl spray absorption process and returned to the 1#PSA adsorption tower to further recover the effective components HF and HCl, and flow out from the bottom of the 2#PSA adsorption tower
  • the desorbed gas is concentrated gas, which is returned to the chlorosilane/HCl spray absorption process to further recover the effective components.
  • the liquid formed after condensation is used as the reflux of the upper rectification.
  • the liquid formed after condensation is returned to the chlorosilane/HCl spray absorption process as an absorbent for recycling.
  • the absorption liquid from chlorosilane/HCl spray absorption process enters multi-stage evaporation, then enters condenser, therefrom obtains the thick HCl gas of gas phase and the bottom of heavy component tower from HF rectification process
  • the fluid is mixed with the non-condensable gas 5 obtained after condensation, and the thick HCl liquid formed after condensation enters the next process—HCl refining, flows out the thick chlorosilane liquid from the condenser, and enters the subsequent chlorosilane.
  • Distillation the non-condensable gas 6 flowing out from the condenser is returned to the medium temperature pressure swing adsorption process after the cold and heat exchange, and the effective components HF and HCl are further recovered.
  • the crude HCl liquid from the multi-stage evaporation/compression/condensation process enters the HCl refining process composed of an HCl rectifying column and a vacuum rectifying column, wherein the HCl rectifying column operating pressure is 0.3 ⁇ 0.6MPa , The operating temperature is 50 ⁇ 80°C, the operating pressure of the vacuum rectifying tower is -0.08 ⁇ -0.1MPa, the operating temperature is 60 ⁇ 120°C, and the HCl product gas with a purity greater than 99.99% flows out from the top of the HCl rectifying tower, and a part is returned to It is recycled in the dry etching process, and part of it is liquefied and recycled as the absorbent in the chlorosilane/HCl spray absorption process.
  • the top gas non-condensable gas 7
  • a part enters the subsequent tail gas absorption process, and a part returns to the medium temperature pressure swing adsorption process, and the heavy component that flows out from the bottom of the vacuum rectification tower, a part returns to the multi-stage evaporation/compression/condensation process, and a part enters
  • the next step is the shallow cooling rectification step of chlorosilane.
  • the chlorosilane liquid flows out from the bottom of the tower, and a part forms a mixed solution with HCl in an appropriate ratio (1:1 ⁇ 1.4) as an absorbent and returns to the chlorosilane/HCl spray absorption process for recycling, and a part is mixed with sulfuric acid as the next process— Used as an absorbent for exhaust gas absorption.
  • Tail gas absorption the light fraction impurity gas distilled from the top of the rectifying tower of the upper section of the HF rectifying process is not condensed with the heavy components flowing out from the bottom of the rectifying tower of the lower section of the HF rectifying process and condensed
  • the gas 5 and a part of the non-condensable gas 7 from the HCl purification process are mixed and then enter the tail gas absorption tower using the chlorosilane liquid from the chlorosilane rectification process in the shallow cooling process and the fresh sulfuric acid mixture as the absorbent, and form fluorine from the bottom of the absorption tower.
  • the silicic acid solution is output as the raw material for the production of AHF by the defluorosilicic acid method, and the raw material liquid is recycled for use, and the non-condensable gas 9 flowing out from the top of the absorption tower is directly discharged as the exhaust gas.
  • the purified raw material gas directly enters the medium temperature pressure swing adsorption process, and flows out from the top of the 1#PSA tower.
  • Crude HF gas, the condensed non-condensable gas 2, the HF aqueous solution with a concentration of 40% is obtained through precision filtration and deionized water absorption, and the non-condensable gas 3 formed after water absorption is hydrogen-rich gas output as fuel
  • the crude HF liquid formed after condensation is subjected to precision filtration and then enters the HF rectification.
  • the desorption gas flowing out from the bottom of the 1#PSA adsorption tower in the desorption step is pressurized to 0.2-0.3MPa and then reduced from 2
  • the bottom of the adsorption tower of #PSA enters, and the intermediate gas of non-adsorption phase flowing out from the top of the 2#PSA adsorption tower in the adsorption step is directly returned to the 1#PSA adsorption tower to further recover the effective components, and from the bottom of the 2#PSA adsorption tower
  • the desorbed gas flowing out is concentrated gas, and the non-condensable gas 1 formed by the newly installed condenser is mixed with the crude HF gas of the medium-temperature pressure swing adsorption process to recover the effective component HF, and the effective component HF is recovered from the newly installed condenser.
  • the liquid formed after the condenser directly enters the HCl refining process to recover HCl, wherein the heavy components flowing out from the HCl refining process are directly discharged after treatment, thus eliminating the need for chlorosilane/HCl spray absorption, multi-stage evaporation/compression / Condensation and rectification of chlorosilanes with medium and shallow cooling.
  • the purified feed gas from the pretreatment process is cooled and heat exchanged to 80-160 After °C, it enters the chlorosilane/HCl spray absorption process, the non-condensable gas 1 flowing out from the top of the spray absorption tower, and the non-condensable gas 2 formed after condensation, then enter the medium-temperature pressure swing adsorption process composed of two stages of PSA.
  • the condensed liquid formed after condensation directly enters the HCl refining process, and the absorption liquid flowing out from the bottom of the spray absorption tower enters the multi-stage evaporation/compression/condensation process.
  • the purified raw material gas from the pretreatment process is cooled and heat exchanged to 80-160 °C after Entering the chlorosilane/HCl spray absorption process, the non-condensable gas 1 flowing out from the top of the spray absorption tower, and the non-condensable gas 2 formed after condensation, then enter the medium-temperature pressure swing adsorption process composed of two-stage PSA, in which the non-condensable gas 2 is formed.
  • the condensed gas 2 enters from the bottom of the 1#PSA adsorption tower after being cooled to 50 ⁇ 80°C.
  • the operating pressure of 1#PSA is 0.2 ⁇ 0.3MPa, and the operating temperature is 50 ⁇ 80°C.
  • the gas flowing out from the top of the adsorption tower in the adsorption step The non-adsorbed phase gas is the intermediate gas and enters the bottom of the 2#PSA adsorption tower.
  • the non-adsorbed phase gas flowing out from the top of the adsorption tower in the adsorption step is the crude HF gas.
  • the condensed non-condensable gas 3 is precisely filtered and deionized.
  • the HF aqueous solution with a concentration of 40% is obtained by water absorption, and the non-condensable gas 4 formed after the water absorption is output as a hydrogen-rich gas, which is used as fuel gas, and the crude HF liquid formed by condensation enters HF after precision filtration.
  • the stripping gas flowing out from the bottom of the 1#PSA adsorption tower in the desorption step and the concentrated gas flowing out from the bottom of the 2#PSA adsorption tower are respectively returned to the chlorosilane/HCl spray absorption process to further recover the effective components, without
  • the condensed liquid formed by the condensation of the condensed gas 1 directly enters the HCl refining process, and the absorption liquid flowing out from the bottom of the spray absorption tower enters the multi-stage evaporation/compression/condensation process.
  • the total concentration of HF and HCl in the raw material gas does not exceed 3% and the H2 content exceeds 90%.
  • the purified raw material gas obtained through the pretreatment process directly enters the first stage of PSA.
  • the medium temperature pressure swing adsorption process composed of, wherein, a PSA is composed of 4 adsorption towers, one adsorption tower is in the adsorption step, and the remaining adsorption towers are in different stages of desorption including decompression and reverse discharge or vacuuming, boosting or final charging.
  • the operating pressure of the adsorption tower is 0.2 ⁇ 0.3MPa
  • the operating temperature is 70 ⁇ 90 °C
  • the purified feed gas enters from the bottom of the PSA adsorption tower
  • the non-adsorption phase gas flowing out from the top of the adsorption tower in the adsorption step is the adsorption waste gas, which is used as the adsorption waste gas.
  • the concentrated gas flowing out from the bottom of the adsorption tower in the desorption step the condensed non-condensable gas 1, mixed with the purified raw material gas and returned to the medium-temperature pressure swing adsorption process to further recover the effective components, and the condensed condensed liquid , and then enter the HF rectification process, the non-condensable gas 2 flowing out from the HF rectification process enters the tail gas absorption process for processing, the HF product gas flowing out from the HF rectification process is returned to the dry etching process for recycling, and the HF rectification process is recycled.
  • the heavy component fluid flowing out from the bottom of the tower is directly purified by HCl, thereby obtaining HCl product gas, which is returned to the dry etching process for recycling, thus eliminating the need for chlorosilane/HCl spray absorption, multi-stage evaporation/compression/condensation, Medium-shallow cold chlorosilane rectification process.
  • This working condition is also suitable for the separation, recovery and reuse of the acidic exhaust gas containing low-concentration HF/HCl after the traditional water-washing absorption method is used to treat the etching tail gas.
  • the purified raw material gas after the pretreatment process is condensed to form a non-condensable Gas 1 is eluted with water to remove a small amount of residual acidic components to produce dilute acid for export treatment.
  • the non-condensable gas 2 washed with water is used as fuel gas.
  • the non-condensable gas 3 flowing out of the distillation process enters the tail gas absorption process for processing, the HF product gas flowing out from the HF rectification process is returned to the dry etching process for recycling, and the heavy component fluid flowing out from the bottom of the HF rectification tower directly enters the HCl refining process , the HCl product gas is thus obtained, and returned to the dry etching process for recycling, thereby eliminating the need for chlorosilane/HCl spray absorption, multi-stage evaporation/compression/condensation, medium-shallow cold chlorosilane rectification and medium-temperature pressure swing adsorption. process.
  • This working condition is also suitable for the separation and recycling of high-concentration HF/HCl generated after plasma cleaning.
  • the non-condensable gas or adsorption waste gas generated after water washing is used as fuel gas, and is converted into the raw material gas for pressure swing adsorption hydrogen extraction , wherein, the non-condensable gas or adsorption waste gas first enters the drying tower, removes the moisture and a small amount of fluorine-containing and chlorine-containing acidic components, and then enters the adsorption purification to remove impurities including silane, phosphine, and metal ions.
  • the hydrogen-rich purified methane hydrogen gas is pressurized to 2.6-3.0 MPa, exchanged cold and heat to normal temperature, and then enters the pressure swing adsorption hydrogen extraction process composed of 5 adsorption towers, and flows out from the top of the adsorption tower.
  • Ultra-pure hydrogen enters the hydrogen purification process consisting of metal getters, so as to obtain H2 product gas that meets the electronic-grade hydrogen standard, and returns to the dry etching process for recycling.
  • the desorbed gas flowing from the bottom of the adsorption tower is rich in methane. gas, which is then used as fuel gas.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Treating Waste Gases (AREA)
  • Gas Separation By Absorption (AREA)
  • Drying Of Semiconductors (AREA)

Abstract

本发明公开了一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，涉及半导体制程中蚀刻尾气的有效组分回收与循环再利用环保领域，其主要步骤为，含有HF/HCl干法蚀刻尾气先后经过预处理、氯硅烷/HCl喷淋吸收、中温变压吸附、HF精馏、多级蒸发/压缩/冷凝、HCl精制、氯硅烷中浅冷精馏与尾气吸收工序，从中获得纯度大于等于99.99％的HF与HCl产品气，并返回干法蚀刻制程中循环使用，其中，中温变压吸附为二段PSA，HF精馏为上下两段，HCl精制为两塔精馏。本发明实现了从含HF/HCl干法蚀刻尾气中分离回收HF与HCl，并返回蚀刻制程中循环使用，大幅度降低了蚀刻气体原料成本与尾气环保处理成本，解决了现有技术仅是达标排放而无法实现尾气综合利用，填补了该技术领域的空白。

Description

一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法 技术领域
本发明涉及半导体制程中蚀刻尾气的有效组分回收与循环再利用环保领域，更具体的说是涉及一种含HF/HCl蚀刻尾气FTrPSA(全温程变压吸附)分离与回收循环再利用方法。
背景技术
在以硅基(Si)或碳化硅(SiC)基的晶圆或外延薄膜上进行蚀刻，是半导体集成电路(IC)等芯片制程中最为重要的步骤，其中，以含氟(F)、氯(Cl)化合物进行等离子或常规气体干法蚀刻，在半导体工业中得到了广泛的应用；比如，通常集成电路(IC)的产生包括沉积、掩模、刻蚀和剥膜等步骤，以便形成和连接像晶体管、电阻和电容那样的电路组件。在IC制程中，需要在一个晶圆或外延薄膜片上同时制作几百到上千个芯片，单个组件的尺寸必须小于0.5μm，并且还有越来越小的趋势，随着超大集成电路(ULSI)芯片的发展需要，蚀刻技术的发展趋势朝着更大面积、更小的蚀刻线宽方向发展，其中，气体干法蚀刻，尤其是等离子气体干法蚀刻业已成为最为广泛应用与发展的一种蚀刻技术，先后出现的反应离子刻蚀(RIE)、电子回旋共振(ECR)、螺旋波源(HWS)和电感耦合等离子体源(ICP)等加工方法和装置就是适应这种高分辨率集成电路要求而产生的，如蚀刻面积大于300mm、蚀刻线宽小于0.1μm等等。
蚀刻(或刻蚀，Etch Film)是有选择性地从硅基或碳化硅基晶圆或外延薄膜(简称“晶圆片”)表面去除不需要的材料的过程，在涂胶的晶圆片上正确地复制掩膜图形。蚀刻也有湿法与干法之分，其中干法蚀刻中的等离子蚀刻业已成为主要的蚀刻工艺，干法蚀刻常用的气体主要是氟基气体及引入Cl、Br基的混合气体，比如，氟化氢(HF)、氯化氢(HCl)、四氟化碳(CF 4)、六氟化硫(SF 6)、三氟化氮(NF 3)、四氯化碳(CCl 4)等等，同时常用氢气(H 2)、氩气(Ar)、氧气(O 2)、氮气(N 2)等作为载气，在低压放电的等离子环境中与晶圆片表面的Si或SiC反应，在气相中生成含有HF、HCl、四氟化硅(SiF 4)、四氯化硅(SiCl 4)、以及少量的四溴化硅(SiBr 4)、硅烷(SiH 4)、一氧化碳(CO)、二氧化碳(CO 2)、水(H 2O)、易挥发有机物(VOC)、微细悬浮的氧化硅(SiO 2)、硅(Si)或碳化硅(SiC)或气溶胶等颗粒以及H 2、N 2、Ar等的蚀刻尾气，因而，蚀刻尾气具有易燃易爆有毒且腐蚀性等特征的危险化学气体，处理方法既要满足大气排放标准，又要在技术经济上行之有效，降低生产成本。
工业上处理蚀刻尾气的主要方法有水洗、酸碱中和、氧化燃烧、吸附与等离子燃烧五种。
水洗法针对蚀刻尾气主要含有酸性极强且有毒杂质的工况，通过水吸收与水气转化，将酸性组分吸收形成液体并将有毒杂质组分转化成无毒物质或沉淀(水浆)实现排放。该法虽然简单便于操作而工业上普遍采用，但由于吸收相平衡及转化效率的限制，以及形成的吸收液具有的极强腐蚀性，导致吸收后的排放气中仍然残留许多酸性杂质组分，很难完全达到排放标准，必须进一步通入空气稀释或燃烧或吸附等其它方法加以处理后，才能达标排放。水洗法也可以采用加热水蒸气，利用较高温度下更有利于将有害杂质转化成无害的氧化物，使得水洗法的净化效率变得更高。水洗法主要问题在于，需要消耗大量的水，并且产生难以回收且腐蚀性极强的氢氟酸、盐酸或氟硅酸等二次污染物，导致处理设备投资较大；同时，水洗法所形成的一些高氟或高氯硅酸与硅或二氧化硅颗粒粉尘极易形成浆状物而堵塞阀门或管道等设备，并且在受热情况下分解腐蚀设备导致泄漏等危害；此外，水洗法对尾气中含有较多水溶性有害杂质组分或容易与水蒸气发生转化反应的工况有一定效果。
酸碱中和法是针对蚀刻尾气具有酸性特点，通过加入诸如氢氧化钙等碱性溶液，将其中的氟离子或HF等形成氟化钙(CaF 2，即人造萤石)或高氟/高氯硅酸钙沉淀或浆而脱除，未吸收的气体再加入其它碱性溶液，进一步脱除其中的酸性杂质，使得尾气中的酸性杂质组分残留达到排放标准。半导体行业中，比较有名的英国爱得华公司(EDWARDS)发明了一种化学中和方法与装置～气体反应器柱(GRC，gasreactorcolumn)，其原理为利用化学中和方法来处理尾气；该装置的柱管里装有适当的无机小颗粒混合物，柱管通电加热到一定的温度后，尾气经过柱管发生中和反应，该气体反应器柱发生的是干式化学反应，可以直接和真空系统连接，尾气通过柱管里的碱性或金属碱性物质发生充分的化学反应，有的转化为惰性物质，有的被化学反应所吸附，使排出的有害尾气大为减少。但是气体柱的更换频率比较高，并且时有不完全吸附或因反应柱失活而导致的有害组分穿透，造成了二次污染。酸碱中和法或化学中和法依旧受到吸收或化学吸附的平衡限制，要彻底使得尾气排放达标，需要多级或多柱中和反应，成本比较高。
氧化燃烧法是利用蚀刻尾气中含有较多易燃性组分，诸如H 2、硅烷、四氟化硅，以及有机物(VOC)等的易燃性，在足够的温度和时间下，通入空气或含氧化合物气体与易燃组分接触进行焚化，使得氧化物能够生成，然后通过热交换将氧化生成物冷却直到凝结而排出，其余残存气体再用碱性溶液洗涤，以去掉废气中的酸性。由于蚀刻尾气中含有较多的不易燃烧的HF、HCl等酸性气体，因此这种方法不适合处理蚀刻尾气，尤其是尾气中含有特定的光刻胶，如聚甲甲酯(PMMA)等，一般很难在清洗工序中被清洗干净，残留在蚀刻尾气中少量的光刻胶不能采用燃烧处理(会形成二噁英或唑噁类有害物质)，只能采用其它的物理方法。目前氧化燃烧法只适用于某些化学气相沉积(CVD)中所产生的尾气处理。
吸附法是依据蚀刻尾气组分与所选择的特定吸附剂之间的物理或化学吸附力大小实现有选择性地分离与净化；常用的三氧化二铝、活性炭或分子筛对极性较强的HF、HCl、H 2O、SiF 4、SiH 4、CO 2和VOC等有明显的吸附作用，不过，由于吸附力强，会导致吸附剂再生相当困难，使用寿命较短和成本上升等问题。值得注意的是，吸附HF所用的吸附剂比较特殊，此类吸附剂多为碱性金属的氟化物，利用金属氟化物与HF在较低温度下发生化学反应而选择性地进行化学吸附，形成金属氟化物-HF的络合物，在较高的温度下再进行络合物的分解反应，从而实现HF从吸附剂上脱附，其它杂质在吸附剂上没有选择性，从而实现了HF的分离与净化。这种化学吸附法适用的工况，大多为氟化反应制备氟氯烷烃(CFC)、含氢氯氟烷烃(HCFC)、含氢氟烷烃(HFC)、硫酰氟(SO 2F 2)等产品的场合，反应所产生的反应混合气对HF的选择性吸附、分离及回收，效果比较好，但吸附剂损失率大。对于含有水或SiF 4或HCl杂质组分的蚀刻尾气，吸附剂因与水等杂质组分也会发生化学反应或共吸附现象，导致吸附剂粉化或过饱和吸附，进而无法有效进行处理与净化；除此之外，采用金属吸气剂或膜分离系统进行选择性吸附，对一些杂质的脱除比较有效，但对蚀刻尾气效果不明显，并且成本较高。吸附法的一个最大问题是，对蚀刻尾气中吸附质(杂质)组分的浓度较低的工况下比较适宜，对浓度较高的杂质组分，往往由于吸附容量的限制，导致吸附剂用量增加，操作成本也随之增加，脱附效果差。
等离子体净化法是目前比较流行的处理方法，尤其对氟化废气，包括蚀刻尾气、氟化氢制备尾气等含HF的尾气。等离子体净化是利用等离子体增强分解(破坏)，直接使有害组分发生转变，这种转变是在一高密度等离子体区完成的，该区由辉光放电或其他放电形式获得，在等离子体中存在大量的活性粒子，这些粒子可破坏蚀刻尾气中有毒及难降解的物质。该法与等离子体蚀刻耦合，是一种非常有前景的尾气处理方法，如脉冲电晕等离子体化学处理(PPCP，pulsed corona Induced plasma)对氮氧化物(NO X)、二氧化硫(SO 2)、汞(Hg)蒸气和易挥发性的有机物(VOCs)有较好的处理效果。对NO X和SO 2的脱除是脉冲电晕产生的强自由基同它们发生的氧化反应，在有添加物(如氨(NH 3)和H 2O)的情况下，使其转化为硫酸盐和硝酸盐；VOCs的脱除是由脉冲电晕产生的高能电子使其激发、分解和电离，最终生成结构简单的CO 2和CO；对氟化尾气，则添加含氢或含氢化合物，比如H 2、NH 3或甲烷(CH 4)，在等离子条件下，使得难与水溶解或难以分解的氟化物等组分分解，产生的氢离子(H+)与氟离子(F-)或氯离子(Cl+)形成HF、HCl，再用水洗将氟化尾气净化。不过，等离子体对HF、HCl等含量比较高且的蚀刻尾气，处理效果一般，并且代价昂贵，只适合小规模的尾气处理。
以上所述的现有蚀刻尾气处理方法均以有毒有害组分无害化且尾气达标排放为主要目 的，尾气中大量非常有价值的HF、HCl或H 2等都无法回收利用。
发明内容
本发明的目的在于：提供一种含HF/HCl蚀刻尾气FTrPSA(全温程变压吸附)分离与回收循环再利用方法，将含HF/HCl/H 2的干法蚀刻尾气中获得高纯度HF、HCl或H 2并返回蚀刻制程循环使用。
全温程变压吸附(英文全称：Full Temperature Range-Pressure Swing Adsorption，简称：FTrPSA)是一种以变压吸附(PSA)为基础并可与各种分离技术相耦合的方法，利用蚀刻尾气中各组分(HF/HCl为有效组分，其余为杂质组分)本身在不同压力与温度下的吸收/吸附/精馏及物理化学性质的差异性，采取以两段中温变压吸附工序为主与喷淋吸收、HF精馏/HCl精制(精馏)及冷凝耦合，使得中温变压吸附过程中吸附与解吸易于匹配和平衡的循环操作来进行分离与净化，从而实现HF/HCl回收并返回蚀刻制程循环使用。
本发明采用的技术方案：一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，原料气，来自硅或碳化硅基晶圆芯片干法蚀刻过程所产生的尾气，主要含有惰性载气(氢气(H 2))、有效组分氟化氢(HF)与氯化氢(HCl)，以及少量的水(H 2O)、四氟化硅(SiF 4)、四氯化硅(SiCl 4)、硅烷(SiH 4)、甲烷(CH 4)、一氧化碳(CO)、二氧化碳(CO 2)，以及微量或痕量的易挥发有机物(VOCs)、金属离子(Me+)、微细固体与气溶胶颗粒(SS)、部分高氟硅烷酸/高氯硅烷的杂质组分，温度为常温(20-25℃)，压力为常压或微正压。
包括如下步骤：
(1)预处理，控制原料气的温度为常温(20-25℃)，压力为0.2～0.3MPa，送入预处理单元先后脱除尘埃、颗粒、油雾、VOCs、高氟硅烷/酸及高氯硅烷，预处理形成的净化原料气进入氯硅烷/HCl喷淋吸收工序，其中，预处理单元包括除尘器、除颗粒过滤器、除油雾捕集器及活性炭吸附器；
(2)氯硅烷/HCl喷淋吸收，氯硅烷/HCl喷淋吸收工序采用氯硅烷与HCl混合液体作为吸收剂的喷淋吸收塔作为反应器，来自预处理工序的净化原料气经过冷热交换至50～80℃后，从喷淋吸收塔底部进入并与吸收剂进行逆向传质交换，其中，从喷淋吸收塔底部流出富集氯硅烷/HCl的吸收液，进入后续的多级蒸发/压缩/冷凝工序，同时从塔底流出的少量残留颗粒、高氯硅烷、高氟硅烷/酸杂质输出进行环保处理，从喷淋吸收塔顶部流出富集HF与低沸点组分的不凝气体1，进入中温变压吸附工序；
(3)中温变压吸附，中温变压吸附工序由两段变压吸附组成，每段变压吸附由2个以上的吸附塔组成，并且至少1个吸附塔处于吸附步骤，其余吸附塔处于解吸步骤，来自氯硅烷/HCl喷淋吸收工序不凝气体1从第一段PSA(1#PSA)吸附塔底进入，1#PSA的操作压力 为0.2～0.3MPa，操作温度为50～80℃，其中，从处于吸附步骤的吸附塔顶部流出的非吸附相气体为粗HF气体，经冷凝后的不凝气体2，经精密过滤及去离子水吸收得到浓度为40％的HF水溶液外输，经水吸收后形成的不凝气体3为富氢气体输出，或作为燃料气使用，或作为变压吸附提氢的原料气，而经冷凝后形成的粗HF液体，经精密过滤后进入下一个工序—HF精馏，从处于解吸步骤的1#PSA吸附塔底流出的解吸气，经增压与冷热交换后从第二段PSA(2#PSA)的吸附塔底进入，2#PSA吸附塔的操作压力为0.2～0.3MPa，操作温度为50～80℃，从处于吸附步骤的2#PSA吸附塔顶流出的非吸附相的中间气体，与来自氯硅烷/HCl喷淋吸收工序的不凝气体1混合返回进入1#PSA吸附塔，进一步回收有效组分HF与HCl，而从2#PSA吸附塔底流出的解吸气为浓缩气体，返回氯硅烷/HCl喷淋吸收工序，进一步回收有效组分；
(4)HF精馏，HF精馏工序包括由上下两段精馏组成精馏塔，来自中温变压吸附工序的粗HF气体经冷凝后得到的精HF液体进入HF精馏工序中的精馏塔，精HF液体从下段精馏塔的顶部或从上段精馏塔的底部进入，其中，从上段精馏塔顶馏出的轻组分杂质气体，返回至后续的尾气吸收工序，从上段精馏塔的底部或从下段精馏塔的顶部馏出物经冷凝后所形成的不凝气体4为无水HF(AHF)气体，纯度大于等于99.99％，直接作为电子级HF产品气，返回干法蚀刻制程循环使用，经冷凝后所形成的液体，作为上段或下段精馏的回流，从下段精馏的底部馏出的含少量重组分杂质组分的塔底物流体，经冷凝后所形成的不凝气体5，一部分进入多级蒸发/压缩/冷凝工序，另一部分进入尾气吸收工序，经冷凝后所形成的液体作为吸收剂返回至氯硅烷/HCl喷淋吸收工序循环使用；
(5)多级蒸发/压缩/冷凝，来自氯硅烷/HCl喷淋吸收工序的吸收液进入多级蒸发，再进入冷凝器，从中得到气相的粗HCl气体与来自HF精馏工序重组分塔底物流体经冷凝后得到的不凝气体5混合，经冷凝后所形成的粗HCl液体进入HCl精制工序，从冷凝器中流出粗氯硅烷液体，进入后续的氯硅烷中浅冷精馏工序，从冷凝器中流出的不凝气体6，经冷热交换后返回至中温变压吸附工序，进一步回收有效组分HF与HCl；
(6)HCl精制，HCl精制工序包括HCl精馏塔与真空精馏塔，HCl精馏塔操作压力为0.3～0.6MPa、操作温度为50～80℃，真空精馏塔操作压力为-0.08～-0.1MPa、操作温度为60～120℃，其中，从HCl精馏塔顶部流出纯度大于99.99％的HCl产品气，一部分返回至干法蚀刻制程中循环使用，另一部分经液化后作为氯硅烷/HCl喷淋吸收工序的吸收剂循环使用，从HCl精馏塔底流出物进入真空精馏塔，从真空精馏塔顶流出的塔顶气为不凝气体7，一部分进入后续的尾气吸收工序，另一部分返回中温变压吸附工序，从真空精馏塔底流出的重组份，一部分返回到多级蒸发/压缩/冷凝工序，另一部分进入氯硅烷中浅冷精馏工序；
(7)氯硅烷中浅冷精馏，氯硅烷中浅冷精馏工序包括精馏塔，来自多级蒸发/压缩/冷凝工序的粗氯硅烷液体，和/或来自HCl精制工序的真空塔底的重组分流体进入的氯硅烷中浅冷精馏工序，操作温度为-35～10℃、操作压力为0.6～2.0MPa，其中，从精馏塔塔顶流出的不凝气体8，经冷热交换后返回至中温变压吸附工序，从精馏塔塔底流出氯硅烷液体，一部分与HCl混合后形成混合液作为吸收剂返回至氯硅烷/HCl喷淋吸收工序循环使用，另一部分与硫酸混合作为尾气吸收工序的吸收剂使用；
(8)尾气吸收，尾气吸收工序采用来自氯硅烷中浅冷精馏工序的氯硅烷液体及新鲜的硫酸混合液为吸收剂的尾气吸收塔作为反应器，来自HF精馏工序的上段精馏塔顶馏出的轻组分杂质气体、来自HF精馏工序的下段精馏塔底流出的重组分并经冷凝后的不凝气体5以及来自HCl精制工序的不凝气体7混合后进入尾气吸收塔，其中，从吸收塔底形成氟硅酸溶液，作为原料输出去氟硅酸法制备AHF生产过程的原料液循环使用，而从吸收塔顶流出的不凝气体9，作为排放气直接排放。
进一步的，所述的原料气中HCl含量小于1％的工况，所述的净化原料气直接进入中温变压吸附工序，从1#PSA塔顶流出的粗HF气体，经冷凝后的不凝气体2，经精密过滤及去离子水吸收得到浓度为40％的HF水溶液外输，经水吸收后形成的不凝气体3为富氢气体输出，或作为燃料气使用，或作为变压吸附提氢的原料气，而经冷凝后形成的粗HF液体，经精密过滤后进入HF精馏，从处于解吸步骤的1#PSA吸附塔底流出的解吸气，经增压与冷热交换后从第二段PSA(2#PSA)的吸附塔底进入，从处于吸附步骤的2#PSA吸附塔顶流出的非吸附相的中间气体直接返回进入1#PSA吸附塔，进一步回收有效组分，而从2#PSA吸附塔底流出的解吸气为浓缩气体，经新增设的冷凝器后所形成的不凝气体1，再与中温变压吸附工序的粗HF气体混合进行回收有效组分HF，而从新增设的冷凝器后所形成的液体，直接进入HCl精制工序回收HCl，其中，从HCl精制工序流出的重组分，经过处理直接排出，由此省去了氯硅烷/HCl喷淋吸收、多级蒸发/压缩/冷凝与中浅冷氯硅烷精馏工序。
进一步的，所述原料气中HF浓度小于HCl浓度时，来自预处理工序的净化原料气，经冷热交换至80～160℃后进入氯硅烷/HCl喷淋吸收工序，从喷淋吸收塔顶流出的不凝气体1，经冷凝后形成的不凝气体2，再进入由两段PSA组成的中温变压吸附工序，经冷凝后形成的冷凝液体，直接进入HCl精制工序，从喷淋吸收塔底流出的吸收液，进入多级蒸发/压缩/冷凝工序。
进一步的，所述的原料气中HF浓度小于HCl浓度时，来自预处理工序的净化原料气，经冷热交换至80～160℃后进入氯硅烷/HCl喷淋吸收工序，从喷淋吸收塔顶流出的不凝气体1，经冷凝后形成的不凝气体2，再进入由两段PSA组成的中温变压吸附工序，其中，不凝 气体2从第一段PSA(1#PSA)吸附塔底进入，1#PSA的操作压力为0.2～0.3MPa，操作温度为50～80℃，从处于吸附步骤的吸附塔顶部流出的非吸附相气体为中间气体进入第二段(2#PSA)吸附塔底，从其处于吸附步骤的吸附塔顶流出的非吸附相气体为粗HF气体，经冷凝后的不凝气体3，经精密过滤及去离子水吸收得到浓度为40％的HF水溶液外输，经水吸收后形成的不凝气体4为富氢气体输出，或作为燃料气使用，或作为变压吸附提氢的原料气，而经冷凝后形成的粗HF液体，经精密过滤后进入HF精馏工序，从处于解吸步骤的1#PSA吸附塔底流出的解吸气以及2#PSA吸附塔底流出的浓缩气体分别返回至氯硅烷/HCl喷淋吸收工序，进一步回收有效组分，不凝气体1经冷凝后形成的冷凝液体，直接进入HCl精制工序，从喷淋吸收塔底流出的吸收液，进入多级蒸发/压缩/冷凝工序。
进一步的，所述原料气中HF与HCl浓度总计不超过3％时，原料气经过预处理工序得到的净化原料气，直接进入由一段PSA组成的中温变压吸附工序，其中，一段PSA由2个以上的吸附塔组成，1个吸附塔处于吸附步骤，其余吸附塔处于包括降压逆放或抽真空、升压或终充的不同阶段的解吸步骤，吸附塔的操作压力为0.2～0.3MPa，操作温度为70～90℃，净化原料气从PSA吸附塔底进入，从处于吸附步骤的吸附塔顶部流出的非吸附相气体为吸附废气，作为燃料气使用，或作为变压吸附提氢的原料气，从处于解吸步骤的吸附塔底流出的浓缩气体，经冷凝后的不凝气体1，与净化原料气混合返回至中温变压吸附工序进一步回收有效组分，经冷凝后的冷凝液体，再进入HF精馏工序，从HF精馏工序流出不凝气体2进入尾气吸收工序进行处理，从HF精馏工序流出的HF产品气，返回至干法蚀刻制程循环使用，从HF精馏塔底流出的重组分流体，直接进入HCl精制，由此获得HCl产品气，返回干法蚀刻制程循环使用，由此，省去了氯硅烷/HCl喷淋吸收、多级蒸发/压缩/冷凝、中浅冷氯硅烷精馏工序,此工况也适合采用传统的水洗吸收法处理蚀刻尾气后的含低浓度HF/HCl酸性排放气的分离与回收再利用。
进一步的，所述的原料气中HF/HCl浓度超过20％时，经预处理工序的净化原料气，经冷凝后形成的不凝气体1，经水洗脱除少量的残留酸性组分，产生稀酸外输处理，经水洗的不凝气体2，作为燃料气或作为变压吸附提氢的原料气，经冷凝后形成的冷凝液，进入HF精馏工序，从HF精馏工序流出不凝气体3进入尾气吸收工序进行处理，从HF精馏工序流出的HF产品气，返回至干法蚀刻制程循环使用，从HF精馏塔底流出的重组分流体，直接进入HCl精制，由此获得HCl产品气，返回干法蚀刻制程循环使用，由此，省去了氯硅烷/HCl喷淋吸收、多级蒸发/压缩/冷凝、中浅冷氯硅烷精馏以及中温变压吸附工序，此工况也适合采用等离子体清洗后产生的含高浓度HF/HCl分离与回收再利用。
进一步的，所述的中温变压吸附工序中变压吸附提氢的原料气为水洗后产生的不凝气体 或吸附废气，其中，不凝气体或吸附废气先进入干燥塔，脱除其中的水分和少量的含氟含氯的酸性组分，然后进入吸附净化，脱除包括硅烷、磷烷、金属离子的杂质，得到富氢的净化甲烷氢气体，经过加压至1.0～3.0MPa、冷热交换至常温(20-25℃)，进入由4个以上吸附塔组成的变压吸附提氢工序，从吸附塔顶流出纯度为99.99～99.999％的超纯氢，进入由钯膜或金属吸气剂组成的氢气纯化工序，从而获得符合电子级氢气标准的H 2产品气，返回至干法蚀刻制程循环使用或外输，从吸附塔底流出的解吸气为富甲烷气体，直接作为燃料气使用。
本发明的有益效果是：
(1)通过本发明实现了从含HF/HCl干法蚀刻尾气中分离回收HF与HCl，并返回蚀刻制程中循环使用，大幅度降低了蚀刻气体原料成本与尾气环保处理成本，解决了现有技术仅是达标排放而无法实现尾气综合利用，填补了该技术领域的空白；
(2)本发明利用原料气中各组分(HF/HCl为有效组分，其余为杂质组分)本身在不同压力与温度下的吸附/吸收/精馏与冷凝系数及物理化学性质的差异性，采取以两段中温变压吸附工序为主与氯硅烷喷淋吸收、HF精馏、HCl精制(精馏)、氯硅烷精馏及蒸发/压缩/冷凝耦合，使得中温变压吸附过程中吸附与解吸易于匹配和平衡的循环操作来进行分离与净化，从而实现HF/HCl与其它杂质组分的分离及提纯，并返回至干法蚀刻制程循环使用；
(3)本发明克服了现有化学吸附法因HF与吸附剂在低温下发生化学(敖合)反应进行吸附而在高温下发生分解反应进行解吸所导致的吸附与解吸频繁循环操作过程中的吸附剂损失率大以及吸附剂因与水等杂质组分也会发生化学反应导致吸附剂粉化与失效严重而无法有效地进行吸附分离的问题，利用HF与HCl两种极性较强吸附容易解吸困难的特征，采用独特的中温变压吸附的物理吸附过程，并通过与精馏或冷凝耦合来调节吸附与解吸的循环操作，可以避免这种现象，使得吸附剂使用寿命长；
(4)本发明在不同的原料气工况下，可以有效地简化流程，实现HF/HCl回收再利用，由此，可以配合传统的以环保为目的的水洗法或等离子体法处理蚀刻尾气，将有效地回收HF/HCl并返回蚀刻制程或干法清洗制程中循环使用，解决了传统处理方法不能回收的缺陷，并同样达到排放要求；
(5)本发明可以从蚀刻尾气中回收HF/HCl循环再利用的同时，也可以通过增设PSA提氢来获得有价值的电子级H 2产品，并可返回干法蚀刻制程循环使用，或作为半导体其它制程的用氢来源，同时，若制程载气为氩气或氮气或与氢混合气，都可以通过调整PSA提氢或提氩或提氮，或增设低温吸附来获取电子级氩气、氮气等产品。
附图说明
图1为本发明实施例1流程示意图；
图2为本发明实施例2流程示意图；
图3为本发明实施例3流程示意图；
图4为本发明实施例4流程示意图；
图5为本发明实施例5流程示意图；
图6为本发明实施例6流程示意图；
图7为本发明实施例7流程示意图。
具体实施方式
为了使本发明的目的、技术方案及优点更加清楚明白，对本发明进行进一步详细说明。应当理解，此处所描述的具体实施例仅用以解释本发明，并不用于限定本发明，即所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。
以下的常温均是指20-25℃，常压即一个大气压。
实施例1
如图1所示，一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，原料气，来自硅基晶圆芯片干法蚀刻过程所产生的尾气，主要含有惰性载气氢气(H 2)83％(v/v)、有效组分氟化氢(HF)9％与氯化氢(HCl)5％，以及少量的水(H 2O)、四氟化硅(SiF 4)、四氯化硅(SiCl 4)、硅烷(SiH 4)、甲烷(CH 4)、一氧化碳(CO)、二氧化碳(CO 2)，以及微量或痕量的易挥发有机物(VOCs)、金属离子(Me+)、微细固体与气溶胶颗粒(SS)、部分高氟硅烷酸/高氯硅烷的杂质组分，常温常压。
具体实施步骤包括，
(1)预处理，原料气经增压后送入由除尘器、除颗粒过滤器、除油雾捕集器及活性炭吸附器组成的预处理单元，在0.2～0.3MPa压力与常温的操作条件下，先后脱除尘埃、颗粒(SS)、油雾、VOCs、高氟硅烷/酸及高氯硅烷，形成的净化原料气进入下一个工序—氯硅烷/HCl喷淋吸收；
(2)氯硅烷/HCl喷淋吸收，来自预处理工序的净化原料气，经过冷热交换至50～80℃后，从喷淋吸收塔底部进入，采用氯硅烷与HCl(1:1～1.4)混合液体作为吸收剂，从喷淋吸收塔顶喷淋而下与净化原料气进行逆向传质交换，从喷淋吸收塔底部流出富集氯硅烷/HCl的吸收液，进入后续的多级蒸发/压缩/冷凝工序，同时从塔底流出的少量残留颗粒、高氯硅烷、高氟硅烷/酸杂质输出进行环保处理，从喷淋吸收塔顶部流出富集HF与低沸点组分的不凝气体1，直接进入下一个工序—中温变压吸附；
(3)中温变压吸附，来自氯硅烷/HCl喷淋吸收工序的不凝气体1，进入由两段变压吸附(PSA)组成的中温变压吸附工序，第一、第二段变压吸附(1#PSA、2#PSA)均由3个吸附 塔组成，1个吸附塔处于吸附步骤，其余2个吸附塔处于包括降压逆放或抽真空、升压或终充的不同阶段的解吸步骤，不凝气体1从1#PSA吸附塔底进入，1#PSA的操作压力为0.2～0.3MPa，操作温度为50～80℃，从处于吸附步骤的吸附塔顶部流出的非吸附相气体为粗HF气体，经冷凝后的不凝气体2，经精密过滤及去离子水吸收得到浓度为40％的HF水溶液外输，经水吸收后形成的不凝气体3为富氢气体输出，作为燃料气使用，而经冷凝后形成的粗HF液体，经精密过滤(小于10微米)后进入下一个工序—HF精馏，从处于解吸步骤的1#PSA吸附塔底流出的解吸气，经增压至0.2～0.3MPa后从2#PSA吸附塔底进入，2#PSA吸附塔的操作压力为0.2～0.3MPa，操作温度为50～80℃，从处于吸附步骤的2#PSA吸附塔顶流出的非吸附相的中间气体，与来自氯硅烷/HCl喷淋吸收工序的不凝气体1混合返回进入1#PSA吸附塔，进一步回收有效组分HF与HCl，而从2#PSA吸附塔底流出的解吸气为浓缩气体，返回氯硅烷/HCl喷淋吸收工序，进一步回收有效组分。
(4)HF精馏，来自中温变压吸附工序的粗HF气体并经冷凝后的精HF液体，进入HF精馏工序的精馏塔，本工序的精馏塔采用上下两段精馏组成，精HF液体从下段精馏的顶部进入，从上段精馏塔顶馏出的轻组分杂质气体进入后续的尾气吸收工序处理，从上段精馏的底部馏出物经冷凝后所形成的不凝气体4为无水HF(AHF)气体，纯度大于等于99.99％，直接作为电子级HF产品气，返回干法蚀刻制程中循环使用，经冷凝后所形成的液体，作为上段精馏的回流，从下段精馏的底部馏出的含少量重组分杂质组分的塔底物流体，经冷凝后所形成的不凝气体5，70％进入下一个工序—多级蒸发/压缩/冷凝，30％进入后续的尾气吸收工序，经冷凝后所形成的液体作为吸收剂返回氯硅烷/HCl喷淋吸收工序循环使用，两段精馏塔的操作温度为18～100℃，操作压力为0.03～0.2MPa。
(5)多级蒸发/压缩/冷凝，来自氯硅烷/HCl喷淋吸收工序的吸收液进入多级蒸发，再进入冷凝器，从中得到气相的粗HCl气体与来自HF精馏工序重组分塔底物流体并经冷凝后得到的不凝气体5混合，经冷凝后所形成的粗HCl液体进入下一工序—HCl精制，从冷凝器中流出粗氯硅烷液体，进入后续的氯硅烷中浅冷精馏，从冷凝器中流出的不凝气体6，经冷热交换后返回至中温变压吸附工序，进一步回收有效组分HF与HCl。
(6)HCl精制，来自多级蒸发/压缩/冷凝工序的粗HCl液体，进入由HCl精馏塔与真空精馏塔组成的HCl精制工序，其中，HCl精馏塔操作压力为0.3～0.6MPa、操作温度为50～80℃，真空精馏塔操作压力为-0.08～-0.1MPa、操作温度为60～120℃，从HCl精馏塔顶部流出纯度大于99.99％的HCl产品气，一部分返回至干法蚀刻制程中循环使用，一部分经液化后作为氯硅烷/HCl喷淋吸收工序的吸收剂循环使用，从HCl精馏塔底流出物进入真空精馏塔，从真空精馏塔顶流出的塔顶气(不凝气体7)，一部分进入后续的尾气吸收工序，一部分返回中温变 压吸附工序，从真空精馏塔底流出的重组份，一部分返回到多级蒸发/压缩/冷凝工序，一部分进入下一工序—氯硅烷中浅冷精馏工序。
(7)氯硅烷中浅冷精馏，来自多级蒸发/压缩/冷凝工序的粗氯硅烷液体，及/或来自HCl精制工序的真空塔底的重组分流体混合后进入的氯硅烷中浅冷精馏工序，操作温度为-35～10℃、操作压力为0.6～2.0MPa，从精馏塔塔顶流出的不凝气体8，经冷热交换后返回至中温变压吸附工序，从精馏塔塔底流出氯硅烷液体，一部分与HCl按适当配比(1:1～1.4)形成混合液作为吸收剂返回至氯硅烷/HCl喷淋吸收工序循环使用，一部分与硫酸混合作为下一个工序—尾气吸收的吸收剂使用。
(8)尾气吸收，来自HF精馏工序的上段精馏塔顶馏出的轻组分杂质气体，与来自HF精馏工序的下段精馏塔底流出的重组分并经冷凝后的一部分不凝气体5以及来自HCl精制工序的一部分不凝气体7混合后进入以来自氯硅烷中浅冷精馏工序的氯硅烷液体及新鲜的硫酸混合液为吸收剂的尾气吸收塔，从吸收塔底形成氟硅酸溶液，作为原料输出去氟硅酸法制备AHF生产过程的原料液循环使用，而从吸收塔顶流出的不凝气体9，作为排放气直接排放。
实施例2
如图2所示，在实施例1基础上，原料气中HCl浓度小于1％、HF浓度增加至13％左右时，净化原料气直接进入中温变压吸附工序，从1#PSA塔顶流出的粗HF气体，经冷凝后的不凝气体2，经精密过滤及去离子水吸收得到浓度为40％的HF水溶液外输，经水吸收后形成的不凝气体3为富氢气体输出，作为燃料气使用，而经冷凝后形成的粗HF液体，经精密过滤后进入HF精馏，从处于解吸步骤的1#PSA吸附塔底流出的解吸气，经增压至0.2～0.3MPa后从2#PSA的吸附塔底进入，从处于吸附步骤的2#PSA吸附塔顶流出的非吸附相的中间气体直接返回进入1#PSA吸附塔，进一步回收有效组分，而从2#PSA吸附塔底流出的解吸气为浓缩气体，经新增设的冷凝器后所形成的不凝气体1，再与中温变压吸附工序的粗HF气体混合进行回收有效组分HF，而从新增设的冷凝器后所形成的液体，直接进入HCl精制工序回收HCl，其中，从HCl精制工序流出的重组分，经过处理直接排出，由此省去了氯硅烷/HCl喷淋吸收、多级蒸发/压缩/冷凝与中浅冷氯硅烷精馏工序。
实施例3
如图3所示，在实施例1基础上，原料气中HF浓度(5％)小于HCl浓度(9％)的工况，来自预处理工序的净化原料气，经冷热交换至80～160℃后进入氯硅烷/HCl喷淋吸收工序，从喷淋吸收塔顶流出的不凝气体1，经冷凝后形成的不凝气体2，再进入由两段PSA组成的中温变压吸附工序，经冷凝后形成的冷凝液体，直接进入HCl精制工序，从喷淋吸收塔底流出的吸收液，进入多级蒸发/压缩/冷凝工序。
实施例4
如图4所示，在实施例1和3基础上，原料气中HF浓度为5％、HCl浓度为9％时，来自预处理工序的净化原料气，经冷热交换至80～160℃后进入氯硅烷/HCl喷淋吸收工序，从喷淋吸收塔顶流出的不凝气体1，经冷凝后形成的不凝气体2，再进入由两段PSA组成的中温变压吸附工序，其中，不凝气体2经冷却至50～80℃后从1#PSA吸附塔底进入，1#PSA的操作压力为0.2～0.3MPa，操作温度为50～80℃，从处于吸附步骤的吸附塔顶部流出的非吸附相气体为中间气体进入2#PSA吸附塔底，从其处于吸附步骤的吸附塔顶流出的非吸附相气体为粗HF气体，经冷凝后的不凝气体3，经精密过滤及去离子水吸收得到浓度为40％的HF水溶液外输，经水吸收后形成的不凝气体4为富氢气体输出，作为燃料气使用，而经冷凝后形成的粗HF液体，经精密过滤后进入HF精馏工序，从处于解吸步骤的1#PSA吸附塔底流出的解吸气以及2#PSA吸附塔底流出的浓缩气体分别返回至氯硅烷/HCl喷淋吸收工序，进一步回收有效组分，不凝气体1经冷凝后形成的冷凝液体，直接进入HCl精制工序，从喷淋吸收塔底流出的吸收液，进入多级蒸发/压缩/冷凝工序。
实施例5
如图5所示，在实施例1基础上，原料气中HF与HCl浓度总计不超过3％而H2含量超过90％的工况，经过预处理工序得到的净化原料气，直接进入由一段PSA组成的中温变压吸附工序，其中，一段PSA由4个吸附塔组成，1个吸附塔处于吸附步骤，其余吸附塔处于包括降压逆放或抽真空、升压或终充的不同阶段的解吸步骤，吸附塔的操作压力为0.2～0.3MPa，操作温度为70～90℃，净化原料气从PSA吸附塔底进入，从处于吸附步骤的吸附塔顶部流出的非吸附相气体为吸附废气，作为燃料气使用，从处于解吸步骤的吸附塔底流出的浓缩气体，经冷凝后的不凝气体1，与净化原料气混合返回至中温变压吸附工序进一步回收有效组分，经冷凝后的冷凝液体，再进入HF精馏工序，从HF精馏工序流出不凝气体2进入尾气吸收工序进行处理，从HF精馏工序流出的HF产品气，返回至干法蚀刻制程中循环使用，从HF精馏塔底流出的重组分流体，直接进入HCl精制，由此获得HCl产品气，返回干法蚀刻制程循环使用，由此，省去了氯硅烷/HCl喷淋吸收、多级蒸发/压缩/冷凝、中浅冷氯硅烷精馏工序。此工况也适合采用传统的水洗吸收法处理蚀刻尾气后的含低浓度HF/HCl酸性排放气的分离与回收再利用。
实施例6
如图6所示，在实施例1的基础上，原料气中HF/HCl浓度为30％而氢气浓度小于70％的工况，经预处理工序的净化原料气，经冷凝后形成的不凝气体1，经水洗脱除少量的残留酸性组分，产生稀酸外输处理，经水洗的不凝气体2，作为燃料气，经冷凝后形成的冷凝液， 进入HF精馏工序，从HF精馏工序流出不凝气体3进入尾气吸收工序进行处理，从HF精馏工序流出的HF产品气，返回至干法蚀刻制程循环使用，从HF精馏塔底流出的重组分流体，直接进入HCl精制，由此获得HCl产品气，返回干法蚀刻制程循环使用，由此，省去了氯硅烷/HCl喷淋吸收、多级蒸发/压缩/冷凝、中浅冷氯硅烷精馏以及中温变压吸附工序。此工况也适合采用等离子体清洗后产生的含高浓度HF/HCl分离与回收再利用。
实施例7
如图7所示，在实施例1～6基础上，中温变压吸附工序，水洗后产生的不凝气体或吸附废气，都作为燃料气使用的，转为作为变压吸附提氢的原料气，其中，不凝气体或吸附废气先进入干燥塔，脱除其中的水分和少量的含氟含氯的酸性组分，然后进入吸附净化，脱除包括硅烷、磷烷、金属离子的杂质，得到富氢的净化甲烷氢气体，经过加压至2.6～3.0MPa、冷热交换至常温，进入由5个吸附塔组成的变压吸附提氢工序，从吸附塔顶流出纯度为99.99～99.999％的超纯氢，进入由金属吸气剂组成的氢气纯化工序，从而获得符合电子级氢气标准的H 2产品气，返回至干法蚀刻制程循环使用，从吸附塔底流出的解吸气为富甲烷气体，再作为燃料气使用。
显而易见的，上面所述的实施例仅仅是本发明实施例中的一部分，而不是全部。基于本发明记载的实施例，本领域技术人员在不付出创造性劳动的情况下得到的其它所有实施例，或在本发明的启示下做出的结构变化，凡是与本发明具有相同或相近的技术方案，均落入本发明的保护范围之内。

Claims (7)

  1. 一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，其特征在于，包括如下步骤：
    (1)预处理，控制原料气的温度为常温，压力为0.2～0.3MPa，送入预处理单元先后脱除尘埃、颗粒、油雾、VOCs、高氟硅烷/酸及高氯硅烷，预处理形成的净化原料气进入氯硅烷/HCl喷淋吸收工序，其中，预处理单元包括除尘器、除颗粒过滤器、除油雾捕集器及活性炭吸附器；
    (2)氯硅烷/HCl喷淋吸收，氯硅烷/HCl喷淋吸收工序采用氯硅烷与HCl混合液体作为吸收剂的喷淋吸收塔作为反应器，来自预处理工序的净化原料气经过冷热交换至50～80℃后，从喷淋吸收塔底部进入并与吸收剂进行逆向传质交换，其中，从喷淋吸收塔底部流出富集氯硅烷/HCl的吸收液，进入后续的多级蒸发/压缩/冷凝工序，同时从塔底流出的少量残留颗粒、高氯硅烷、高氟硅烷/酸杂质输出进行环保处理，从喷淋吸收塔顶部流出富集HF与低沸点组分的不凝气体1，进入中温变压吸附工序；
    (3)中温变压吸附，中温变压吸附工序由两段变压吸附组成，每段变压吸附由2个以上的吸附塔组成，并且至少1个吸附塔处于吸附步骤，其余吸附塔处于解吸步骤，来自氯硅烷/HCl喷淋吸收工序不凝气体1从第一段变压吸附1#PSA吸附塔底进入，1#PSA的操作压力为0.2～0.3MPa，操作温度为50～80℃，其中，从处于吸附步骤的吸附塔顶部流出的非吸附相气体为粗HF气体，经冷凝后的不凝气体2，经精密过滤及去离子水吸收得到浓度为40％的HF水溶液外输，经水吸收后形成的不凝气体3为富氢气体输出，或作为燃料气使用，或作为变压吸附提氢的原料气，经冷凝后形成的粗HF液体，经精密过滤后进入HF精馏工序，从处于解吸步骤的1#PSA吸附塔底流出的解吸气，经增压与冷热交换后从第二段变压吸附2#PSA的吸附塔底进入，2#PSA吸附塔的操作压力为0.2～0.3MPa，操作温度为50～80℃，从处于吸附步骤的2#PSA吸附塔顶流出的非吸附相的中间气体，与来自氯硅烷/HCl喷淋吸收工序的不凝气体1混合返回进入1#PSA吸附塔，进一步回收有效组分HF与HCl，从2#PSA吸附塔底流出的解吸气为浓缩气体，返回氯硅烷/HCl喷淋吸收工序，进一步回收有效组分；
    (4)HF精馏，HF精馏工序包括由上下两段精馏组成精馏塔，来自中温变压吸附工序的粗HF气体经冷凝后得到的精HF液体进入HF精馏工序中的精馏塔，精HF液体从下段精馏塔的顶部或从上段精馏塔的底部进入，其中，从上段精馏塔顶馏出的轻组分杂质气体，返回至后续的尾气吸收工序，从上段精馏塔的底部或从下段精馏塔的顶部馏出物经冷凝后所形成的不凝气体4为无水HF气体，纯度大于等于99.99％，直接作为电子级HF产品气，返回 干法蚀刻制程循环使用，经冷凝后所形成的液体，作为上段或下段精馏的回流，从下段精馏的底部馏出的含少量重组分杂质组分的塔底物流体，经冷凝后所形成的不凝气体5，一部分进入多级蒸发/压缩/冷凝工序，另一部分进入尾气吸收工序，经冷凝后所形成的液体作为吸收剂返回至氯硅烷/HCl喷淋吸收工序循环使用；
    (5)多级蒸发/压缩/冷凝，来自氯硅烷/HCl喷淋吸收工序的吸收液进入多级蒸发，再进入冷凝器，从中得到气相的粗HCl气体与来自HF精馏工序重组分塔底物流体经冷凝后得到的不凝气体5混合，经冷凝后所形成的粗HCl液体进入HCl精制工序，从冷凝器中流出粗氯硅烷液体，进入后续的氯硅烷中浅冷精馏工序，从冷凝器中流出的不凝气体6，经冷热交换后返回至中温变压吸附工序，进一步回收有效组分HF与HCl；
    (6)HCl精制，HCl精制工序包括HCl精馏塔与真空精馏塔，HCl精馏塔操作压力为0.3～0.6MPa、操作温度为50～80℃，真空精馏塔操作压力为-0.08～-0.1MPa、操作温度为60～120℃，其中，从HCl精馏塔顶部流出纯度大于99.99％的HCl产品气，一部分返回至干法蚀刻制程中循环使用，另一部分经液化后作为氯硅烷/HCl喷淋吸收工序的吸收剂循环使用，从HCl精馏塔底流出物进入真空精馏塔，从真空精馏塔顶流出的塔顶气为不凝气体7，一部分进入后续的尾气吸收工序，另一部分返回中温变压吸附工序，从真空精馏塔底流出的重组份，一部分返回到多级蒸发/压缩/冷凝工序，另一部分进入氯硅烷中浅冷精馏工序；
    (7)氯硅烷中浅冷精馏，氯硅烷中浅冷精馏工序包括精馏塔，来自多级蒸发/压缩/冷凝工序的粗氯硅烷液体，和/或来自HCl精制工序的真空塔底的重组分流体进入的氯硅烷中浅冷精馏工序，操作温度为-35～10℃、操作压力为0.6～2.0MPa，其中，从精馏塔塔顶流出的不凝气体8，经冷热交换后返回至中温变压吸附工序，从精馏塔塔底流出氯硅烷液体，一部分与HCl混合形成混合液作为吸收剂返回至氯硅烷/HCl喷淋吸收工序循环使用，另一部分与硫酸混合作为尾气吸收工序的吸收剂使用；
    (8)尾气吸收，尾气吸收工序采用来自氯硅烷中浅冷精馏工序的氯硅烷液体及硫酸混合液为吸收剂的尾气吸收塔作为反应器，来自HF精馏工序的上段精馏塔顶馏出的轻组分杂质气体、来自HF精馏工序的下段精馏塔底流出的重组分并经冷凝后的不凝气体5以及来自HCl精制工序的不凝气体7进入尾气吸收塔，其中，从吸收塔底形成氟硅酸溶液，作为原料输出去氟硅酸法制备AHF生产过程的原料液循环使用，而从吸收塔顶流出的不凝气体9，作为排放气直接排放。
  2. 如权利要求1所述的一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，其特征在于，所述原料气中HCl含量小于1％的时，所述净化原料气直接进入中温变压吸附工序，从1#PSA塔顶流出的粗HF气体，经冷凝后的不凝气体2，经精密过滤及去离子水吸 收得到浓度为40％的HF水溶液外输，经水吸收后形成的不凝气体3为富氢气体输出，或作为燃料气使用，或作为变压吸附提氢的原料气，而经冷凝后形成的粗HF液体，经精密过滤后进入HF精馏，从处于解吸步骤的1#PSA吸附塔底流出的解吸气，经增压与冷热交换后从2#PSA的吸附塔底进入，从处于吸附步骤的2#PSA吸附塔顶流出的非吸附相的中间气体直接返回进入1#PSA吸附塔，进一步回收有效组分，而从2#PSA吸附塔底流出的解吸气为浓缩气体，经新增设的冷凝器后所形成的不凝气体1，再与中温变压吸附工序的粗HF气体混合进行回收有效组分HF，而从新增设的冷凝器后所形成的液体，直接进入HCl精制工序回收HCl，其中，从HCl精制工序流出的重组分，经过处理直接排出，由此省去了氯硅烷/HCl喷淋吸收、多级蒸发/压缩/冷凝与中浅冷氯硅烷精馏工序。
  3. 如权利要求1所述的一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，其特征在于，所述原料气中HF浓度小于HCl浓度时，来自预处理工序的净化原料气，经冷热交换至80～160℃后进入氯硅烷/HCl喷淋吸收工序，从喷淋吸收塔顶流出的不凝气体1，经冷凝后形成的不凝气体2，再进入由两段PSA组成的中温变压吸附工序，经冷凝后形成的冷凝液体，直接进入HCl精制工序，从喷淋吸收塔底流出的吸收液，进入多级蒸发/压缩/冷凝工序。
  4. 如权利要求3所述的一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，其特征在于，所述的原料气中HF浓度小于HCl浓度时，来自预处理工序的净化原料气，经冷热交换至80～160℃后进入氯硅烷/HCl喷淋吸收工序，从喷淋吸收塔顶流出的不凝气体1，经冷凝后形成的不凝气体2，再进入由两段PSA组成的中温变压吸附工序，其中，不凝气体2从1#PSA吸附塔底进入，1#PSA的操作压力为0.2～0.3MPa，操作温度为50～80℃，从处于吸附步骤的吸附塔顶部流出的非吸附相气体为中间气体进入2#PSA吸附塔底，从其处于吸附步骤的吸附塔顶流出的非吸附相气体为粗HF气体，经冷凝后的不凝气体3，经精密过滤及去离子水吸收得到浓度为40％的HF水溶液外输，经水吸收后形成的不凝气体4为富氢气体输出，或作为燃料气使用，或作为变压吸附提氢的原料气，而经冷凝后形成的粗HF液体，经精密过滤后进入HF精馏工序，从处于解吸步骤的1#PSA吸附塔底流出的解吸气以及2#PSA吸附塔底流出的浓缩气体分别返回至氯硅烷/HCl喷淋吸收工序，进一步回收有效组分，不凝气体1经冷凝后形成的冷凝液体，直接进入HCl精制工序，从喷淋吸收塔底流出的吸收液，进入多级蒸发/压缩/冷凝工序。
  5. 如权利要求1所述的一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，其特征在于，所述原料气中HF与HCl浓度总计不超过3％时，原料气经过预处理工序得到的净化原料气，直接进入由一段PSA组成的中温变压吸附工序，其中，一段PSA由2个以 上的吸附塔组成，1个吸附塔处于吸附步骤，其余吸附塔处于包括降压逆放或抽真空、升压或终充的不同阶段的解吸步骤，吸附塔的操作压力为0.2～0.3MPa，操作温度为70～90℃，净化原料气从PSA吸附塔底进入，从处于吸附步骤的吸附塔顶部流出的非吸附相气体为吸附废气，作为燃料气使用，或作为变压吸附提氢的原料气，从处于解吸步骤的吸附塔底流出的浓缩气体，经冷凝后的不凝气体1，与净化原料气混合返回至中温变压吸附工序进一步回收有效组分，经冷凝后的冷凝液体，再进入HF精馏工序，从HF精馏工序流出不凝气体2进入尾气吸收工序进行处理，从HF精馏工序流出的HF产品气，返回至干法蚀刻制程循环使用，从HF精馏塔底流出的重组分流体，直接进入HCl精制，由此获得HCl产品气，返回干法蚀刻制程循环使用，由此，省去了氯硅烷/HCl喷淋吸收、多级蒸发/压缩/冷凝、中浅冷氯硅烷精馏工序，此工况也适合采用传统的水洗吸收法处理蚀刻尾气后的含低浓度HF/HCl酸性排放气的分离与回收再利用。
  6. 如权利要求1所述的一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，其特征在于，所述的原料气中HF/HCl浓度超过20％时，经预处理工序的净化原料气，经冷凝后形成的不凝气体1，经水洗脱除少量的残留酸性组分，产生稀酸外输处理，经水洗的不凝气体2，作为燃料气或作为变压吸附提氢的原料气，经冷凝后形成的冷凝液，进入HF精馏工序，从HF精馏工序流出不凝气体3进入尾气吸收工序进行处理，从HF精馏工序流出的HF产品气，返回至干法蚀刻制程循环使用，从HF精馏塔底流出的重组分流体，直接进入HCl精制，由此获得HCl产品气，返回干法蚀刻制程循环使用，由此，省去了氯硅烷/HCl喷淋吸收、多级蒸发/压缩/冷凝、中浅冷氯硅烷精馏以及中温变压吸附工序，此工况也适合采用等离子体清洗后产生的含高浓度HF/HCl分离与回收再利用。
  7. 如权利要求1-6任一项所述的一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法，其特征在于，所述的中温变压吸附工序中变压吸附提氢的原料气为水洗后产生的不凝气体或吸附废气，其中，不凝气体或吸附废气先进入干燥塔，脱除其中的水分和少量的含氟含氯的酸性组分，然后进入吸附净化，脱除包括硅烷、磷烷、金属离子的杂质，得到富氢的净化甲烷氢气体，经过加压至1.0～3.0MPa、冷热交换至常温，进入由4个以上吸附塔组成的变压吸附提氢工序，从吸附塔顶流出纯度为99.99～99.999％的超纯氢，进入由钯膜或金属吸气剂组成的氢气纯化工序，从而获得符合电子级氢气标准的H 2产品气，返回至干法蚀刻制程循环使用或外输，从吸附塔底流出的解吸气为富甲烷气体，直接作为燃料气使用。
PCT/CN2021/094254 2020-12-16 2021-05-18 一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法 WO2022127019A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2022512788A JP7541763B2 (ja) 2020-12-16 2021-05-18 ＦＴｒＰＳＡによるＨＦ／ＨＣｌ含有エッチング排ガスの分離と回収循環再利用方法

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202011485842.2A CN112707373B (zh) 2020-12-16 2020-12-16 一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法
CN202011485842.2 2020-12-16

Publications (1)

Publication Number Publication Date
WO2022127019A1 true WO2022127019A1 (zh) 2022-06-23

Family

ID=75543422

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/094254 WO2022127019A1 (zh) 2020-12-16 2021-05-18 一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法

Country Status (3)

Country Link
JP (1) JP7541763B2 (zh)
CN (1) CN112707373B (zh)
WO (1) WO2022127019A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115231524A (zh) * 2022-07-12 2022-10-25 浙江省天正设计工程有限公司 一种氟化工生产中含氟化氢尾气的分离纯化方法和装置
CN115650240A (zh) * 2022-09-08 2023-01-31 洛阳中硅高科技有限公司 一氯硅烷的制备方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112707373B (zh) * 2020-12-16 2022-06-10 浙江天采云集科技股份有限公司 一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法
CN113860257B (zh) * 2021-11-04 2022-04-22 浙江容跃环保科技有限公司 玻璃薄化废酸液再生回收的方法及系统

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09267016A (ja) * 1996-01-29 1997-10-14 Toyo Eng Corp 改良された圧力スイング吸着法
CN105854516A (zh) * 2016-03-31 2016-08-17 四川天采科技有限责任公司 一种炼厂干气同时回收h2和c2及以上组分的全温程变压吸附方法
CN108658042A (zh) * 2018-05-29 2018-10-16 四川天采科技有限责任公司 一种led-mocvd制程尾气全温程变压吸附全组分回收再利用方法
CN108744882A (zh) * 2018-05-29 2018-11-06 浙江天采云集科技股份有限公司 一种led-mocvd制程废气全温程变压吸附提氨再利用的方法
US20180318750A1 (en) * 2016-03-31 2018-11-08 Sichuan Techairs Co., Ltd. Method for Gas Separation, Purification and Clarification by FTrPSA
CN109092010A (zh) * 2018-05-29 2018-12-28 浙江天采云集科技股份有限公司 一种led-mocvd制程废气全温程变压吸附提氢再利用的方法
CN211799895U (zh) * 2020-03-17 2020-10-30 大连海奥膜技术有限公司 一种分离含有氯化氢和氢气混合气体的工艺系统
CN112591711A (zh) * 2020-12-16 2021-04-02 浙江天采云集科技股份有限公司 一种HF/HCl混合气体高纯度高收率的FTrPSA分离与净化提取方法
CN112707373A (zh) * 2020-12-16 2021-04-27 浙江天采云集科技股份有限公司 一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7790130B2 (en) * 2007-08-31 2010-09-07 Uop Llc Wide mesoporous alumina composites having trimodal pore structure
JP6433867B2 (ja) 2015-08-28 2018-12-05 信越化学工業株式会社 水素ガス回収システムおよび水素ガスの分離回収方法
CN108715436B (zh) * 2018-05-29 2019-11-08 四川天采科技有限责任公司 半导体制程常压废氢气全温程变压吸附提纯再利用的方法
CN109045965B (zh) 2018-09-03 2024-05-31 环境保护部华南环境科学研究所 一种废气净化系统及方法

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09267016A (ja) * 1996-01-29 1997-10-14 Toyo Eng Corp 改良された圧力スイング吸着法
CN105854516A (zh) * 2016-03-31 2016-08-17 四川天采科技有限责任公司 一种炼厂干气同时回收h2和c2及以上组分的全温程变压吸附方法
US20180318750A1 (en) * 2016-03-31 2018-11-08 Sichuan Techairs Co., Ltd. Method for Gas Separation, Purification and Clarification by FTrPSA
CN108658042A (zh) * 2018-05-29 2018-10-16 四川天采科技有限责任公司 一种led-mocvd制程尾气全温程变压吸附全组分回收再利用方法
CN108744882A (zh) * 2018-05-29 2018-11-06 浙江天采云集科技股份有限公司 一种led-mocvd制程废气全温程变压吸附提氨再利用的方法
CN109092010A (zh) * 2018-05-29 2018-12-28 浙江天采云集科技股份有限公司 一种led-mocvd制程废气全温程变压吸附提氢再利用的方法
CN211799895U (zh) * 2020-03-17 2020-10-30 大连海奥膜技术有限公司 一种分离含有氯化氢和氢气混合气体的工艺系统
CN112591711A (zh) * 2020-12-16 2021-04-02 浙江天采云集科技股份有限公司 一种HF/HCl混合气体高纯度高收率的FTrPSA分离与净化提取方法
CN112707373A (zh) * 2020-12-16 2021-04-27 浙江天采云集科技股份有限公司 一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115231524A (zh) * 2022-07-12 2022-10-25 浙江省天正设计工程有限公司 一种氟化工生产中含氟化氢尾气的分离纯化方法和装置
CN115231524B (zh) * 2022-07-12 2024-03-12 浙江省天正设计工程有限公司 一种氟化工生产中含氟化氢尾气的分离纯化方法和装置
CN115650240A (zh) * 2022-09-08 2023-01-31 洛阳中硅高科技有限公司 一氯硅烷的制备方法

Also Published As

Publication number Publication date
CN112707373A (zh) 2021-04-27
JP7541763B2 (ja) 2024-08-29
JP2023535850A (ja) 2023-08-22
CN112707373B (zh) 2022-06-10

Similar Documents

Publication Publication Date Title
WO2022127019A1 (zh) 一种含HF/HCl蚀刻尾气FTrPSA分离与回收循环再利用方法
TWI691359B (zh) 半導體製程常壓廢氫氣全溫程變壓吸附提純再利用的方法
TWI776056B (zh) 一種led-mocvd製程廢氣全溫程變壓吸附提氨再利用的方法
JP3152389B2 (ja) 膜によるフルオロケミカルの分離回収方法
JP3284096B2 (ja) ペルフルオロ化合物の分離及び精製方法及びシステム
CN112266318A (zh) 一种六氟-1,3-丁二烯分级提纯的方法
CN113354508B (zh) 一种用于电子级气体的节能提纯装置及节能提纯工艺
JP2023524919A (ja) 工業レベルの高濃度ＨＦを電子レベルのＦＴｒＰＳＡに精製する分離及び純化方法
JP2012106146A (ja) 排ガス処理装置および排ガス処理方法
CN112591711B (zh) 一种HF/HCl混合气体高纯度高收率的FTrPSA分离与净化提取方法
KR101843563B1 (ko) 벤트개념을 이용한 난분해성 유해가스 농축분리 시스템 및 및 이의 운전방법
CN112744787B (zh) 一种含高浓度HF的HCl气体深度脱氟干燥的FTrPSA分离与净化方法
CN112827319B (zh) 一种含低浓度硅烷与碳二以上轻烃类的氯基SiC-CVD外延尾气全温程变压吸附提氢与循环再利用方法
CN114307517A (zh) 惰性气体保护的高纯全氟碳电子特气吸附纯化方法
CN112777569B (zh) 一种氟基SiC-CVD晶体与薄膜生长制程尾气FTrPSA全组分回收再利用方法
CN112642259A (zh) 一种烷烃与硅烷反应的氯基SiC-CVD外延制程尾气FTrPSA回收方法
CN112755725B (zh) 一种含HF工业尾气FTrPSA有效组分回收再利用的方法
CN112645335B (zh) 一种外延制程尾气全温程变压吸附提取硅烷的方法
CN112661112A (zh) 一种基于有机硅与H2反应的SiC-CVD外延制程尾气FTrPSA提氢与循环再利用方法
JP3908819B2 (ja) フロンの回収方法
JP3463873B2 (ja) パーフルオロコンパウンドのリサイクル利用方法
CN112827322B (zh) 乙烯与硅烷反应的氯基SiC-CVD外延制程尾气FTrPSA回收与循环再利用方法
CN114180535B (zh) 一种四氟化硫的生产提纯工艺及系统
CN112661158B (zh) 一种氯基SiC-CVD晶体与薄膜生长制程尾气中C2+与氯硅烷FTrPSA分离方法
CN112624050B (zh) 一种含低浓度HF的HCl气体深度脱氟干燥的FTrPSA分离与净化方法

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2022512788

Country of ref document: JP

Kind code of ref document: A

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21904957

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21904957

Country of ref document: EP

Kind code of ref document: A1