Embodiment
Fig. 1 has described thevalve member 10 of the micro machining that is used for gas chromatographic analysis instrument (summary).Valvemember 10 has the stratiform structure that is bonded together by which floor different thin layer usually, comprising the valve seat plate with uppervalve base surface 14 orvalve seat layer 12,flexible layer 18 and stopper layer 20.Stopper layer 20 can be carried out control to the displacement ofvariant diaphragm cell 22A, 22B, 22C, 22D, 22E and 22F in theflexible layer 18.
Eachdiaphragm cell 22A-22D all with valve seatupper surface 14 onrespective valve seat 24A, the 24B, 24C, 24D, 24E and the 24F that form realize aiming at.Eachdiaphragm cell 22A-22F carries out sealing to twovalve ports 30 and 32 that illustrate on eachvalve seat 24A-24F respectively.Valveport 30 and 32 and the pipeline layer 34 of below realize pipeline connections.Pipeline layer 34 makes each valve unit be interconnected in the mode shown in the arrow in scheming 38.
Working gas is controlled byvalve port 40A, 40B, 40C, 40D, 40E and 40F by the flow ofvalve member 10, and its controlling method is to control the displacement of eachdiaphragm cell 22A-22F by apply suitable pressure difference ondiaphragm cell.Pipeline 50,51,52,53,54 and 55 atstopper layer 20 internal shapings has the function of working fluid tocontrol valve port 40A-40F guiding together with the pipeline that is shaped in top layer 56.
Whenmanufacturing valve member 10, each thin layer is made by fine machining method, for example can adopt the various photetchs that comprise the etch method, also can adopt static discharge processing method (EDM), in addition, if select for use glass, and need to be provided with necessary pipeline in the glassy layer, adopt mechanography or laser processing technology that pipeline is shaped as sheet material.
Selected materials can be the brittle material that any efficient semiconductor material or other and working gas do not react.Silicon is very suitable material concerningvalve seat layer 12,stopper layer 20, pipeline layer 34 and top layer 56.Some other material also can be used to manufacture one or more retes wherein, for example glass or sapphire.Each rete is not to select a kind of material only for use.
Although the valve seat of manufacturing according to prior art is the control gaseous flow effectively, it does not have helium leak test level tightness (10-10The sealing characteristics of atmcc He/sec level).In the past, diaphragm material is selected for use exposed and is had the flexible organic material of metal surface, kapton as E.I.Du Pont Company's production, and will be tightly connected between the redundance of flexible layer and the silicon layer with the glass sintering thing that forms at a lower temperature, but this structure can not form helium leak test level tightness.The present invention realizes that the bubble-tight conventional method of helium leak test level is to use the plastic material that can keep its plastic deformation shape when valve event.This plastic material (as thermosetting property or thermoplastic polymer) is attached to or is bonded on the flexible organic material.Be attached to clutch stratum boundary on the plastic material make flexible organic/plastic membrane portions of pulling on the condensation material, and when valve closing and valve seat keep in touch.The clutch layer keeps apart plastic material and valve seat to prevent plastic material and valve seat adhesion.
Contain the material that technique for sticking provided by the present invention andrete 18 are adopted in thevalve member 10, this point will be passed through with reference to serial Fig. 2 A-2C, 3A-3F, 4A-4D and 5A-5E hereinafter, or exploded view 6 is for being described.For the needs of explaining,valve member 10 is used as an example here and is introduced, but it is not unique embodiment.U. S. Patent 4,869,282 have described the working method and the structure thereof ofvalve member 10, and this patent is introduced as a reference at this.
Can leavevalve port 30 and 32 (referring to Fig. 2 A) by the etch method on the valve seat layer 12.For improving sealing characteristics, also can further onvalve port 30 and 32, makecrisperding 60; Butcrisperding 60 is not to have.Clutch layer 62 can be formed by materials such as gold, it is by technological method deposition formations onvalve seat 24 such as sputter, evaporation or electroless platings, its effect be stop to the adhesion ofvalve seat layer 12 and withplastic material 64 adhesions, the thermoplastic polytetrafluoroethylene FEP film thatplastic material 64 can select for use E.I.Du Pont Company to produce.Theplastic material 64 that is shaped combines the kapton that this flexible organic material can select for use E.I.Du Pont Company to produce with flexible organic material 66 (full amination) usually.So theflexible layer 18 of shaping is just on thesurface 14 attached to valve seat layer 12.Except full amination film, E.I.Du Pont Company also produces teflon FEP and Kapton foil respectively, and these materials all can use.
The organic material that is shaped/plastic materialcomposite bed 18 andstopper layer 20 join (shown in Fig. 2 B).If desired, can addstatic connection layer 61 betweenorganic material 66 andstopper layer 20, the material ofstatic connection layer 61 can be selected teflon FEP film etc. for use.Comprisecontrol valve port 40 in thestopper layer 20, the diaphragm cell displacement when this valve port is used for the control valve action.The final stratiform structure that forms is cut into small pieces, with these matrixs with suitable connection material adhesion in the valve casing (not shown), promptly form each valve unit.
For realizing helium leak test level gas,plastic material 64 is molded on thevalve seat 24 shown in figure F2B, and the manufacturing technology that is adopted is " thermoforming " technology that hereinafter described valve is heated and exerts pressure.If adopt teflon FEP film, then this manufacturing technology requires valve unit is heated to 215 °-350 ° Celsius, and requires to apply 20-100 pound/inch by 40 pairs ofdiaphragm cells 22 of control valve port2Pressure.The profile that the thermoforming manufacturing technology makesdiaphragm cell 22press valve seat 24 is shaped.Theclutch layer 62 of profiling has stoped the adhesion of 64 pairs ofvalve seats 24 of plastic material andcrisperding 60 when valve event.
Observation result demonstrates: at about 80 ° degrees centigrade up and down repeatedly after the circular heating, adopt teflon FEP film to keep helium leak test level tightness as the valve template of plastic layer.This operating temperature also can improve, and its measure is to manufactureplastic layer 64 with other suitable thermoplasticity plastic material, the teflon PFA film that for example can adopt E.I.Du Pont Company to produce.If adopt teflon PFA film, in the thermoforming manufacturing technology, need to increase required pressure and temperature so that barrier film can be on valve seat correct pressing mold.
Fig. 3 A to 3F has described the another kind of mould-forming method of valve member of the present invention.At first as shown in Figure 3A, onvalve seat layer 12, leave requiredvalve port 30 and 32 with the etch method,clutch layer 62 profiling on the surface ofvalve seat layer 12 andcrisperding 60 is come out, and wherein, the 12 lip-deep profiling of valve seat layer define the position ofvalve seat 24 in diaphragm area.Thereafter, shown in Fig. 3 C, flexible organic material mentioned above/plastic materialcomposite bed 18 is coated over the upper surface ofclutch layer 62, and fits at the peripheral edge portion ofvalve seat 24 and the upper surface of valve seat layer 12.In Fig. 3 D,stopper layer 20 is bonded on flexible organic material/plastic material composite bed, and if desired, and available staticadhesive layer 61 is bonding.According to the requirement of thermoforming manufacturing technology, makeplastic material 64 invalve seat 24 and crisperding 60 places shapings (shown in Fig. 3 E) by applying above described temperature and gas pressure.After the desired temperature and pressure of thermoforming manufacturing technology is removed, apply suitable pressure so thatbarrier film 22 rises fromvalve seat 24 atvalve port 30 and 32, shown in Fig. 3 F.Because it is tighter thatplastic material 64 andclutch layer 62 are fitted, and loose because of not existing adhering layer to fit betweenclutch layer 62 and thevalve seat layer 12, soclutch layer 12 is transferred on theplastic layer 64 fromvalve seat layer 12, and may stayresidual limit 65 at crisperding 60 places.
Compare with the technology shown in Fig. 2 A-2C, the technology shown in above-mentioned Fig. 3 A-3F can be made more level and smooth clutch layer, and can duplicate the profile ofvalve seat 24 more accurately.
Fig. 4 A to 4D has described another method for production of valve member of the present invention.Eachvalve port 30 and 32 places etch the thin connecting band 70 (shown in Fig. 4 A) of one 25 micron thickness on valve seat layer 12.If desired, this thin connectingband 70 can be had a special style, for example can adopt the method that all etches recessed portion on the two sides of silicon layer for forming crisperding 60.Perhaps, can will can not form crisperding so only in the etching of the bottom side of valve seat layer 12.Clutch layer 62 profiling that are used for definingvalve seat 24 scopes cover on thevalve seat layer 12 that comprises connecting band 70.Above-mentioned flexible organic material/plastic material composite diaphragm covers the upper surface ofclutch layer 62, and is shaped under vacuum state and is bonded in the upper surface ofvalve seat layer 12 andclutch layer 62, and at this moment,plastic material layer 64 also is molded in the outer rim position of valve seat 24.In Fig. 4 C,stopper layer 20 is bonded on flexible organic material/plastic materialcomposite diaphragm 18 by adopting suitable adhesive material 61 (can be poly tetrafluoroethylene or spin polyimide adhesive).With plasma close etchingmethod connecting band 70 is removed subsequently.Atvalve port 30 with 32 places apply suitable pressure difference so thatdiaphragm cell 22 breaks away fromvalve seat layer 12 shown in Fig. 4D.Diaphragm cell 22 by craftwork manufacture shown in Fig. 4 A to 4D has a plug shape part 73 that meshes withvalve seat 24, this plug shape part is covered or encapsulates by the clutch layer fully, thereby make the surface of diaphragm cell have more durability, in addition sinceplastic material 64 by local restriction, therefore the plastic deformation of barrier film under higher temperature also reduces.Clutch layer 62 has formed metal retarded layer or the blocking layer to working air current.
Fig. 5 A-5E has described another method for production of valve member of the present invention.Eachvalve port 30 and 32 places etch the thin connecting band 70 (shown in Fig. 4 A) of one 25 micron thickness on valve seat layer 12.If desired, this thin connectingband 70 can be a special style, for example can adopt the method that all etches recessed portion on the two sides of silicon layer for forming crisperding 60.Clutch layer 62 profiling that are used for definingvalve seat 24 scopes cover on thevalve seat layer 12 that comprises connecting band 70.In this method, it is thepolymer 72 of basic composition thatplastic material 64 contains with the thermosetting property solvent, and as high flatness spinning polyimide, this base polymer has the spin properties of fluid, can casting (curing) and shaping on thevalve seat 24 of profiling.Poly-epoxy imines and other similar polymer spinning, atomizing or casting also may be utilized.Another kind of available thermosetting polymer contains the benzocyclobutane that Dow chemical company produces.Further, can add bonding catalyst (as aluminum oxide) betweenclutch layer 62 andpolyimide layer 72, this is because polyimide is equally very weak usually to the Adhesion force of clutch layer 62 (as gold) with benzocyclobutane.
Through 300-350 ℃ degree centigrade curing baking (its objective is and strengthen thermosetting or crosslinked polymer degree), thermoplastic polymer (long Pu Dun-teflon PFA) is in bonding and shaping on polyimide under the vacuum state, shown in Fig. 5 C.If adopt spinning, binder atomizing or casting, as polyimide or poly-epoxy imines, so just can not use the thermoplastic adhesive, will makediaphragm cell 22 harder like this, the material plastic deformation is littler under high temperature condition, durability is also better simultaneously.
Among Fig. 5 D, the staticadhesive layer 61 ofstopper layer 20 usefulness is bonded on flexible organic material/plastic material composite diaphragm, theadhesive layer 61 that is adopted can be a thermoplastic polytetrafluoroethylene FEP film, also can be the poly-epoxy imines binder of teflon PFA film or thermosetting property.Makeflexible partition unit 22 be separated fromvalve seat layer 12 by apply suitable pressure atvalve port 30 and 32, shown in Fig. 5 E.Method shown in Fig. 5 A-5E also can form the plug shape part 73 that is covered fully byclutch layer 62.
Fig. 6 has described the another kind of method of manufacturing valve member of the present invention, and this method is particularly suitable for manufacturing thevalve member 100 that can produce millimicro upgrading gas or fluid sample volume.Containsilicon layer 101 in thisnotes sample valve 100, made threevalve seat 102A, 102B, 102C and corresponding valve port 113,119 and 125 thereof with fine machining method on the silicon layer.Thepath 10 made from etching on anothersilicon layer 104 6 is communicated with the valve port in thesilicon layer 101 113 and 119.Thepart 108 that one section reduced cross-sectional area is arranged in thepath 10 6, when superheated steam when the pipeline 102, neck downportions 108 can make the enough big pressure difference of formation between in the pipeline 102 110 sections and 113 sections.Branch road 111 makes between thevalve port 113 on pipeline 110 and thevalve seat 102A and realizes that gas circuit is communicated with, another kind oflike branch road 115 make that the realization gas circuit is communicated with between thevalve port 119 onpipeline 112 and thevalve seat 102C.
Clutch layer 114 (as gold) is deposited on eachvalve seat 102A-102C and goes up to define the scope of membrane portions on the respective valve seat.Eachvalve seat 102A-102C leaves a connecting band (being similar to connectingband 70 shown in Fig. 5 C) when preliminary working.
To contain the polyimide of solvent basis composition or poly-epoxy imines binder (as French Cemota with spinning, spraying or casting method, the IP542 binder that 69390 Vernaison produce) coversvalve seat 102A-102C surface and corresponding connecting band surface on thesilicon layer 101, toast one suitable period then and desolvate to remove.Because originally polyimide is liquid, so can be molded into the profile of valve seat.Thepolyimide film 116 that toasted is stayedsilicon layer 101 surfaces, with method for plasma etching and nichrome mask the redundance of itscontinuous part 103 is removed, thereby make it to be configured as asmall channel 118, this passage runs through eachvalve seat 102A-102C, when corresponding valve barrier film is opened, this passage will select corresponding valve port to realize that gas circuit is communicated with invalve port 125 threes of valve port 113,119 and valveseat 102B.Passage 118 has determined the sample volume that introduction valve produced.In described embodiment,manufacturing passage 118 with mask means or etching is in order to produce small volume gas sample (as 1 millilambda).
After this, flexible organic layer 121 (as kapton) is deployed on a certain particular jig (not shown), then, be that the polyimide adhesive 123 of basic composition is spun on flexibleorganic layer 121 and is toasted with solvent, so just formed the roughly composite membrane shown among the figure 120.Then,composite membrane 120 is bonded in (simultaneously to flexibleorganic film 121 heating and pressurization) on thepolyimide layer 116 of etching and processing, to form rete 117.Because the fitting surface ofrete 116 and 120 is all polyimide material, thereby has formedhomogeneous rete 117,passage 118 does not wherein make its etching part be filled after sealing-in.Polymer material 123 has following performance: its certain part can be removed after molded by profiling, and again with another kind of suitable polymers come bonding it the time can not fill the part that is removed.
After this, with method for plasma etching the connecting band among eachvalve seat 102A-102C is removed and specific stopper layer 140 (shown in Figure 7, as to be similar to Fig. 2 C, 3F, thestopper layer 20 among 4D and the 5E) is bonded on kapton-binder composite bed.The effect ofstopper layer 140 is restrictionflexible partition unit 117A, 117B and 117C displacements with respect tovalve seat 102A-102C.Also have control valve port (as valve port 142) in thestopper layer 140, its effect is to produce control force to form the displacement ofdiaphragm cell 117B.
Fig. 8 is the work schematic representation of valve member 100.Source of the gas 130 communicates at port one 32 places withpath 10 6.Gas passes 134 places, another port thatpath 10 6 flows topath 10 6.When needing to gather the gas sample,diaphragm cell 117A and 117C onvalve seat 102A and the 102C are shifted, thereby a part of gas is flow through along etched channels in therete 117 118 andvalve port 113 and 119.Because there is pressure difference in the two ends of thenecking section 108 ofmain passage 106, so gas sample is able to inlet passage 118.Then,diaphragm cell 117A onvalve seat 102A and the 102C and 117C begin action to closecorresponding valve port 113 and 119, and gas sample is trapped in the passage 118.Thereafter, thediaphragm cell 117B on thevalve seat 102B is shifted, thereby thevalve port 125 that gas sample is passed on thevalve seat102B leaves passage 118.
In described embodiment, the control force thatvalve seat 102A and 102C go up diaphragm cell acts on the surface of flexibleorganic material 121, and this control force is less.Formed pressure difference between the elevated pressures in pressure that this is less and thepath 10 6, thereby madebarrier film 117 break away from its valve seat.Valvemember 100 is particularly useful for ion mass-spectrometer, because this quasi-instrument requires tested gas sample to have small volume (as less than 100 millilambdas).Valvemember 100 has been realized helium leak test level tightness under big pressure difference condition, so just eliminated the complexity that multistage step-down measure is had.
When being used for ion mass-spectrometer 143,123 pairs of ion mass-spectrometer assemblies 143 of valve port are opened.Because the working pressure very low (10 of ion mass-spectrometer-6Atm), therefore be difficult to displacement with pressure official post barrier film 117B.In the case, the displacement of barrier film should realize that such as adoptingactuator 144, the working method of this actuator can be thatflexible partition 117 is applied pulling force, also can be to carry out hydraulic driving with piston with other method.
Should be able to recognize although the description of this invention, is proficient in the colleague in this field based on preferred embodiment: the variation on form and the details does not deviate from thought of the present invention and scope.