CN109966820A - The method of processing gas logistics - Google Patents

The method of processing gas logistics Download PDF

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Publication number
CN109966820A
CN109966820A CN201711461304.8A CN201711461304A CN109966820A CN 109966820 A CN109966820 A CN 109966820A CN 201711461304 A CN201711461304 A CN 201711461304A CN 109966820 A CN109966820 A CN 109966820A
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CN
China
Prior art keywords
liquid
gas stream
acid
acidity
gas
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Pending
Application number
CN201711461304.8A
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Chinese (zh)
Inventor
纪和春
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Individual
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Individual
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Priority to CN201711461304.8A priority Critical patent/CN109966820A/en
Publication of CN109966820A publication Critical patent/CN109966820A/en
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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D47/00—Separating dispersed particles from gases, air or vapours by liquid as separating agent
    • B01D47/02—Separating dispersed particles from gases, air or vapours by liquid as separating agent by passing the gas or air or vapour over or through a liquid bath
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B01D53/1456—Removing acid components
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B01D53/18—Absorbing units; Liquid distributors therefor
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
    • C23C16/4401—Means for minimising impurities, e.g. dust, moisture or residual gas, in the reaction chamber
    • C23C16/4402—Reduction of impurities in the source gas
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/02104—Forming layers
    • H01L21/02365—Forming inorganic semiconducting materials on a substrate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
    • H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
    • H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
    • H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
    • H01L21/3065—Plasma etching; Reactive-ion etching

Abstract

The invention discloses the method and apparatus of processing gas logistics.The method of gas stream of the processing containing acid and solid particulate matter, method includes the following steps: passing through aqueous cleaning liquid circulation includes the substantially closed loop of acid sour removing unit for reducing the liquid；At least part circulating liquid is provided to gas scrubbing unit；Gas stream is provided to washing unit；Monitoring is supplied to the acidity of the liquid of washing unit；With the acid reduction for controlling the liquid, this depends on monitored acidity, come control the gas stream in described at least part of circulating liquid solid component dissolubility.The present invention also provides the device for handling the gas stream containing acid and solid particulate matter, closed loop has the input hole for receiving the liquid being discharged from washing unit.

Description

The method of processing gas logistics
Technical field
The present invention relates to the method and apparatus of processing gas logistics.
Background technique
Chemical vapor deposition (CVD) is used for deposition film or layer on the surface in the substrate or chip that are located in settling chamber.It is this Method operates in this way: in excitation chemical reaction under conditions of substrate surface occurs, by one or more reactant gases It is supplied to the room, carrier gas is usually used, reaches the substrate surface.For example, TEOS and one of oxygen and ozone can be mentioned Settling chamber is supplied to silicon oxide layer is formed on the substrate, and silane and ammonia can be provided to form silicon nitride layer.Polysilicon leads to Heating is crossed to decompose silane or chlorosilane, is deposited in substrate.Gas is also supplied to etching chamber to carry out the region of sedimentary Selection etching, such as formed semiconductor equipment electrode and source/drain region during.Etching gas may include perfluorinated (PFC) gas such as CF4, C2F6, C3F8 and C4F8, however other suitable etchants include fluorine, NF3, SF6 and hydrofluorocarbon gas Such as CHF3, C2HF5 and CH2F2.Usually using such gas come the nitride that is formed on the polysilicon layer or oxide skin(coating) Opening is formed in region, and it is photo-etched the exposure of glue (photoresist) layer.Argon gas is usually defeated also together with etching gas The room is sent to provide and promote gas for carrying out the method in etching chamber.
During such engraving method, usually there is being contained in for residual volume to pass through what vacuum pump took out from etching chamber The by-product such as SiF4 and COF2 and inert gas of the gas for being provided to etching chamber and lithographic method in discharge gas are such as Ar.Other nitrogen is often added to purge gas of the discharge gas as vacuum pump.
Above-mentioned perfluorinated gas is greenhouse gases, and therefore provides and disappear before discharge gas is discharged into atmosphere Except PFC gas is converted water soluble fluoridized hydrogen by equipment such as thermal treatment unit (TPU) or plasma abatement apparatus, and will SiF4 is converted into SiO2.Gas stream is subsequently conveyed to washing unit, wherein HF to be dissolved in the water for being supplied to washing unit In.
Our Co-pending U.S. Patent Application 2006/0101995A1, content are incorporated herein by reference, retouch The device for being followed by subsequent processing the acidic HF solution formed in washing unit is stated.HF solution is transported to sour removing unit, Preferably in the form of electrochemical cell, for removing HF from acid solution.Water is returned to washing unit by sour removing unit, And HF is discharged in the form of dense HF solution.This solution can be subsequently processed,, should precipitate CaF2 using calcium salt CaF2 can be compacted and dry for further using.
Solid particulate matter is entrained in into the gas stream of washing unit such as SiO2 particulate matter, is transferred to and passes through In the water of washing unit.Some SiO2 particulate matters, such as about 30-60ppm will be dissolved in the water by washing unit, however Remaining will be kept in water in the form of solid particulate matter.To avoid these particulate matters in electrochemical cell and/or washing unit Building up inside provides one or more cartridge filters or similar devices in battery upstream, thus by these particulate matters from washing unit It is removed in the HF solution being discharged.
Method depending on carrying out in process chamber, the amount of entrained solid particulate matter can change in gas stream, Generally between 70 and 200ppm.We have found that when the amount of solid particulate matter is higher, cartridge filter can soon by It fills up.For example, when gas stream includes the SiO2 particulate matter of 200ppm, respectively with four cartridge filters of about 4-5kg capacity It can be filled in less than one week.Since replacement each cost is at present in US $ 200 or so, this may increase significantly Processing unit possesses cost.
Summary of the invention.
The method of gas stream the present invention provides processing containing acid and solid particulate matter, method includes the following steps:
Passing through aqueous cleaning liquid circulation includes the substantially closed of acid sour removing unit for reducing the liquid Loop provides at least part circulating liquid to gas scrubbing unit, provides gas stream to washing unit, monitoring is supplied to The acidity of the liquid of washing unit, and the acid reduction of the control liquid, this depends on monitored acidity, to control Make the dissolubility of the solid component of the gas stream in described at least part of circulating liquid.
The method of gas stream the present invention also provides processing containing acid and solid particulate matter, this method includes following step Rapid: passing through aqueous cleaning liquid circulation includes the substantially closed ring of acid electrochemical cell for reducing the liquid A certain proportion of circulating liquid for leaving closed loop is transferred to gas scrubbing unit by road, and it is single to washing to provide gas stream Member makes transfer liquid back to closed loop, monitoring is in closed loop at a certain position for dissolving in transfer liquid The acidity of circulating liquid, and the acid reduction of the control liquid, this depends on monitored acidity, to control transfer liquid In gas stream solid component dissolubility.
Enter the acidity of the wash liquid of washing unit by controlling, and is particularly derived from sour contained in gas stream Acidity can improve dissolubility of the solid particulate matter in wash liquid significantly.Acid bigger, particulate matter is in wash liquid Solubility may be bigger.For example, the silicide particle object such as SiO2 particulate matter in the gas stream containing HF can be dissolved in hydrogen Fluosilicate is formed in fluorspar acid solution.This fluosilicate can then pass through electrochemical cell together with number acid from washing It is removed in liquid.Therefore, it can improve significantly for being mentioned from the closed loop for removing solid particulate matter in wash liquid The service life of any cartridge filter or other equipment that supply.Although any acid can be used to realize in benefit of the invention, By forming fluosilicate rather than silicic acid, HF has maximum influence to the dissolubility of SiO2.
The acidity of transfer liquid be preferably maintained at predetermined value or more than.For example, if in gas stream Acid is HF, and the concentration of the HF in transfer liquid can be maintained at 400ppm or more, so as to the SiO2 of the concentration of about 200ppm It can substantially completely be dissolved in the liquid.
The acidity of circulating liquid can be monitored in any suitable position.For example, tightly in a certain proportion of circulation fluid Body, which is transferred to the upstream of the position of washing unit or downstream, can monitor acidity.Transfer liquid, which can be returned to, is located at closure It storage container in loop and is mixed in wherein transfer liquid with the liquid that electrochemical cell is discharged.In this case, The acidity for the liquid being stored in storage container can be monitored.Storage container can have fluid provider, entered by its water and closed Cyclization road.
The acid of liquid can be monitored by measuring the conductivity of liquid.It, can be with by understanding the composition of gas stream Estimate contribution of the sour gas to the conductivity of liquid, and therefore the conductivity of liquid can provide the acid finger of liquid Mark.Alternatively, the acid more precise measurement of liquid can be obtained using online acid analyzer, the acid contained in the gas stream When being HF or HCl, the online acid analyzer is preferably halide analyser.
In preferred embodiments, electrochemical cell includes the ion-exchange unit of electrochemical regeneration.The unit is excellent Selection of land includes ion exchange material, is used to absorb selected ion from liquid and applies electric field across it and cause institute The Ion transfer of absorption enters individual concentrate solution by ion exchange material, and wherein adjusts the intensity of electric field, this Depending on the concentration monitored.Concentrate solution can cycle through electrochemical cell.Regularly, a certain proportion of concentrate is molten Liquid can be transported to reaction member, wherein ionic species such as acid and fluosilicate in solution is made to become insoluble.
Ion exchange material is used to capture the ion exchange of considered ion and preferably particle or bead form Resin or other materials, water permeable medium can be provided, ionic adsorption medium and ion conducting medium, ions can To be moved in concentrate solution by applied electric field.The particle or bead of resin can be loose and be maintained at two Appropriate position between film and entrance and outlet sinters is to be that the liquid institute containing ion is permeable.Alternatively, particle or Bead can be the form of adherency, together with adhesive bond.Such as applied in the thickness across ion exchange material Potential is used to drive captured ion by ion exchange material, and towards one or the other in a pair of electrodes, potential is logical Cross its application.Adjust electrode between potential or electric current adjustable the captured ion of size by ion exchange material into Enter the mobility of concentrate solution, this controls the adsorption rate of the ion from wash liquid again, and therefore enters close ring The acidity for the liquid that the electrochemical cell on road is discharged.
Method of the invention is suitable for processing gas logistics comprising a variety of acid, such as HF, HCl, HNO3, H2SO4, H3BO3 At least one of with H3PO4.
The present invention also provides the devices for handling the gas stream containing acid and solid particulate matter comprising gas scrubbing list Member, substantially closed loop circulation, the latter include the pump for making aqueous cleaning liquid surround closed loop circulation, are used for The acid electrochemical cell of circulating liquid is reduced, and for a certain proportion of circulating liquid for leaving closed loop to be transferred to The delivery outlet of gas scrubbing unit, gas scrubbing unit have the first entrance for receiving transfer liquid, are turning for receiving The second entrance of the gas stream of dissolution and transfer liquid pass through it from the outlet that washing unit is discharged, closure in liquid relief body Loop has the input hole for receiving the liquid being discharged from washing unit；For monitoring in closed loop at a certain position The acid equipment of liquid, and the acid reduced controller for controlling the liquid, this depends on monitored concentration Come control the gas stream in transfer liquid solid component dissolubility.
Specific embodiment.
In the present embodiment, gas stream is discharged from the process chamber of plasma etch reactor, mentions in Xiang Suoshu reactor For the process gas including etchant and oxygen as reactant, to carry out the technique in the chamber.Suitable etching The example of agent includes the perfluorochemical with general formula CxFyHz, wherein x >=1, y >=1 and z >=0, such as CF4, C2F6, C3F8, C4F8, CHF3, C2HF5 and CH2F2.Other suitable etchants include NF3 and SF6.Argon gas is alternatively arranged as that gas is promoted to mention For for carrying out the technique in room.
During etching technics, only the reactant of only a part will be consumed, and the gas being therefore discharged from process chamber Logistics by comprising reactant, be supplied to the mixed of any non-reacted inert gas of the room and by-product from etch process Close object.For example, gas stream may include the mixture of CxFyHz, O2, Ar, SiF4 and COF2.Above-mentioned perfluorinated gas is not It is dissolved in water, and therefore before gas stream is transported to washing unit, is such as heat-treated list by eliminating equipment (not shown) First (TPU) or plasma abatement apparatus, to convert water soluble acid HF for perfluorinated gas.It is any in gas stream SiF4 will be converted into SiO2, be become entrained in gas stream in the form of solid particulate matter.Alternatively, washing unit can be with It is provided by the combination of TPU and wet scrubber, and therefore can not need individually to eliminate equipment.
Aqueous cleaning liquid is provided to the fluid provider 16 of each washing unit by service 18.Device includes Substantially closed loop 20, wash liquid is recycled continually by pump 22 wherein.
Closed loop has delivery outlet 24 (can be transferred in service by its a certain proportion of circulating liquid) It (is then returned to by being connected to the recurrent canal of the fluid outlet aperture of each washing unit by its transfer liquid with input hole Closed loop).In the present embodiment, it by the excitation of the supply valve between service and respective fluid provider, follows Ring wash liquid is transferred in service.
Closed loop includes fluid-storing container or tank 34, and there are three fluid providers for tool.First fluid ingate connects The water from water supplying pipe road is received, for initially preparing the wash liquid recycled in closed loop.Second fluid ingate connects Receive the circulating liquid from closed loop.The input hole of closed loop provides third fluid provider.Tank further comprises fluid Outlet returns to closed loop by its liquid.
The liquid for entering closed loop from tank passes sequentially through pump 22 (recycling liquid in closed loop),
One or more filters unit (for removing particulate matter from liquid), heat exchanger 44, fluid analyzer, and be used for The acid sour removing unit for reducing the liquid, then returnes to tank 34.
Fluid analyzer monitors the acidity of circulating liquid, and the circulating liquid is diverted through delivery outlet 24 and reaches supply pipe Road.In the present embodiment, fluid analyzer is tightly located at the downstream of delivery outlet, will pass through the acid of the liquid of fluid analyzer Property will be identical with any liquid for being displaced through delivery outlet.Alternatively, fluid analyzer can be tightly positioned at the upper of delivery outlet Trip, also will be identical with any liquid for being displaced through delivery outlet will pass through the acid of liquid of fluid analyzer.In this reality It applies in example, online halide analyser provides fluid analyzer.Fluid analyzer output signal, indicates by therein The acidity of liquid, the signal are received by controller.
The acid alternative that circulating liquid is monitored as fluid analyzer is used, can provide conductivity in tank Sensor monitors the conductivity of the liquid stored in tank, and the liquid pumped out from the fluid outlet of tank from there through pump Conductivity.Sensor can indicate the conductivity of the liquid in tank to controller output signal.The conductivity of liquid can mention For the acid index of liquid, at this time into the composition of the gas stream of washing unit, and thus the composition of circulating liquid is It is known.Controller using signal or contained in information form control signal, be provided to sour removing unit to control The acid reduction of circulating liquid.
In operation, the valve in water supplying pipe road is initially turned on to provide a certain amount of water (such as 160 liters) to tank 34 In.Supply valve is initially to close.Once the water valve 60 that tank 34 is measured required for having supplied to give be closed and pump operation from And recycle water in closed loop 20.Therefore, the wash liquid initially recycled in closed loop 20 is water.
Under above-mentioned introduction of the invention, those skilled in the art can carry out various change on the basis of the above embodiments Into and deformation, and these improve or deformation be within the scope of the present invention.
It will be understood by those skilled in the art that specific descriptions above are intended merely to explain the purpose of the present invention, not use In the limitation present invention.Protection scope of the present invention is defined by the claims and their equivalents.

Claims (10)

1. a kind of method of gas stream of the processing containing acid and solid particulate matter, method includes the following steps:
Passing through aqueous cleaning liquid circulation includes the substantially closed of acid sour removing unit for reducing the liquid Loop；At least part circulating liquid is provided to gas scrubbing unit；Gas stream is provided to washing unit；Monitoring is supplied to The acidity of the liquid of washing unit；With the acid reduction for controlling the liquid, this depends on monitored acidity, to control Make the dissolubility of the solid component of the gas stream in described at least part of circulating liquid.
2. the method according to claim 1, wherein at least part circulating liquid is transferred and leaves closed loop, and with Closed loop is returned to afterwards.
3. method according to claim 1 or 2, wherein sour removing unit is electrochemical cell.
4. according to the method in claim 3, wherein electrochemical cell include electrochemical regeneration ion-exchange unit.
5. according to the method in claim 3, wherein electrochemical cell includes ion exchange material, it is used to absorb institute from liquid The ion of selection and apply electric field across it and to cause absorbed Ion transfer to enter by ion exchange material individual Solution, and the intensity of electric field is wherein adjusted, this depends on monitored concentration.
6. method according to claim 1 or 2, wherein the solid component of gas stream is the silicon-based compositions of gas stream.
7. method according to claim 1 or 2, wherein the solid component of gas stream is silica.
8. method according to claim 1 or 2, wherein monitoring the acidity of liquid by the conductivity for measuring liquid.
9. method according to claim 1 or 2 wherein acid includes halide, and is wherein supervised using online acid analyzer The acidity of draining body.
10. method according to claim 9, wherein online acidity analyzer is halide analyser.
CN201711461304.8A 2017-12-28 2017-12-28 The method of processing gas logistics Pending CN109966820A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201711461304.8A CN109966820A (en) 2017-12-28 2017-12-28 The method of processing gas logistics

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201711461304.8A CN109966820A (en) 2017-12-28 2017-12-28 The method of processing gas logistics

Publications (1)

Publication Number Publication Date
CN109966820A true CN109966820A (en) 2019-07-05

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
CN201711461304.8A Pending CN109966820A (en) 2017-12-28 2017-12-28 The method of processing gas logistics

Country Status (1)

Country Link
CN (1) CN109966820A (en)

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Application publication date: 20190705

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