CN1070417A

CN1070417A - Moisture resistant electrical adhesives and methods of making and using the same

Info

Publication number: CN1070417A
Application number: CN 92104503
Authority: CN
Inventors: 戴维·杜兰特; 戴维P维奥; 塔·施因·威; 安一林·楚
Original assignee: David P. Vio
Current assignee: David P. Vio
Priority date: 1989-11-14
Filing date: 1992-06-10
Publication date: 1993-03-31
Also published as: CN1054092A

Abstract

An electrically conductive adhesive having a very stable electrical conductivity at high temperatures when bonding electrically conductive mating surfaces, the adhesive comprising a carrier having a volume shrinkage value of greater than about 6.8% and a filler which may comprise agglomerates, granules, powders, flakes, particles of an outer plated nickel, glass spheres of an outer plated metal, the filler having particle size and surface characteristics which provide for electrical contact stability due to moisture resistant contact on electronic component leads. The volume shrinkage of the support between the unset and the set state is greater than 68%, thus placing the filler particles in compression, facilitating electrical contact of the surfaces to be joined, and bringing the particles themselves to a density that enhances the interaction between the particles.

Description

Electrically conductive cements and production and preparation method thereof

The application for the applicant be in the checking process and common known application number is No.07/436199, the applying date is on November 14th, 1989, denomination of invention is that " electroconductive binder " and application number are No.07/533682, the applying date is June 4 nineteen ninety, and denomination of invention is the continuation part of " electroconductive binder and production and preparation method thereof " these two parts of U.S. Patent applications.

The present invention relates to a kind of electroconductive binder or be cementing agent, particularly relate to a kind of electroconductive binder that under the very big condition of high temperature and humidity, has good long-term behaviour.

Electroconductive binder and cementing agent generally are by list or non-conductive solid support material of polycomponent and conductive filler material, make as metal or metallic particles.When can be with various tackiness agents during as carrier, just having used polycomponent resin, single component be the system and the above-mentioned mixture thereof of major ingredient with the solvent.Resin has the long shelf-life, good bonding characteristic, and can solidify with multiple material production.Equally, by removing the solvent in the system that single component is major ingredient with the solvent, can make single component easily is the material and the curing of multiple material production of main component with the solvent, forms the bonding of intensity height and dependable performance.Above-mentioned filler is generally the precious metal of various particle diameters, as gold or silver-colored.Filler is the sheet of various particle diameters and the mixture of non-platy shaped particle preferably.Above-mentioned particle is mainly solid, in some cases, and also can be for being coated with the electrical insulator of metal.Constitute by general, conductive filler material can account for about 75% or vast scale more of carrier-containing material gross weight, and carrier accounts for remaining 25% or still less.It is generally acknowledged, form electron channel in the carrier that solidifies because lamellar body tends to arrange by continuous bonding relation, therefore in the form of sheets or the particle of sheet crystalline metal or outer metallizing provide very strong conductive characteristic for this electroconductive binder.Think that in carrier non-sheet conductive filler material then can insert in the gap between the platy shaped particle to strengthen electroconductibility.

Can adopt subtractive-type process that modern circuit is made traditional printed circuit board (P C B S).In the method, copper coin pattern and joining region forming circuit, this circuit are by forming being fixed to the corrosion of non-conductive plate of rigidity or on-chip copper foil layer.The usually outer lead that is coated with scolder on the electronic component is passed the fixed orifices of offering on the printed circuit board (PCB), and the lead that will plate scolder outward is connected on the joining region in succession by lead/soldering, thereby above-mentioned electronic component is connected on the sort circuit.It is also well-known to make so-called " flexible circuit ", in sort circuit, as polyimide or polyester sheet, for example on the such flexible flake or substrate of the KAPTONTM polyimide of 1 to 5 mil thickness, forms copper coin pattern and joining region.Pass fixed orifices in the flexible flake by lead, and connect with lead/soldering these leads are connected on the joining region, thereby electronic component is connected on the sort circuit them.Recently, people have been developed into a kind of surperficial immobilising device (SMC), in this device, the device lead only be fixed on the joining region above, and be soldered on its position, form a joining on butt.The surface technique for fixing can be used on rigidity and the flexible substrate.

Along with under all temps and humidity condition, the particularly improvement of its performance under the very big condition of high temperature and humidity, traditional welding process has reached quite high state of the art.Yet, artificially on substrate, make circuit, traditional welding process usually will adopt various etching reagent and similar chemical preparations to carry out large-scale chemical treatment.In order to be welded to connect effectively, may also want various soldering fluxs and solvent.In addition, in order to dissolve welding material rapidly to form joint, traditional welding process also will be used a large amount of heats.The heat that produces when though rigid substrate and some expensive polyimide can be used to absorb welding, yet because the cross-sectional height of flexible substrate is quite little, thermal capacity is low, and easily deformable, so the then easier calorific loss that causes of flexible substrate made of the lower polymkeric substance of use cost such as polyester.Such as, the on-chip welding joint of flexible polyester may cause the part " fold " of substrate, the change of various joining regions centering size, and the distortion of whole substrate.

So people attempt to adopt conductive ink, tackiness agent and cementing agent are substituted in the traditional welding method of attachment of using in rigidity and the flexible substrate.Such as, the conductive printed circuit that present people will include the joining region is printed on the flexible polyester substrate, bonds on the joining region with the conducting end of electroconductive binder with surperficial retaining element (SMC) circuit bank then.The advantage of above-mentioned way is that the shape of made flexible print circuit can change easily, thereby can put into certain special installation housing, makes housing have very big handiness in design.In addition, estimate to adopt the conduction printing, the open method of attachment of the success of tackiness agent and low-cost flexible substrate is compared and can be reduced cost greatly with traditional welding process.Resemble employed " electroconductive binder " expression here and be used between monomer such as lead and joining region, forming any mixture or the material that electrically contacts with mechanical connection.

Though the electroconductibility of general electroconductive binder is not so good as the electroconductibility of solid metal and welding alloy usually, yet the electroconductibility of electroconductive binder (for example: each adhint is 100 megaohms, and each welding joint is 10 megaohms) is enough big for many circuit.Such as, be when having the resistance of hundreds of or several kilohms or bigger resistance or other parts at element, the influence of the contact resistance about 1 ohm between this element lead and its joining region almost can be ignored.Though in the use of low resistance circuit, contact resistance becomes and wants more important, yet circuit layout can be become can adapt to accumulation contact resistance in a big way usually.Except the resistance aspect of contact resistance, the variation that contact resistance reaches its stability quality of difference of environment in time also is a considerable importance.Because not having the method for attachment of needed stability is not suitable for using under many occasions, therefore just need a kind of like this method of attachment, promptly utilize this method can form joint, and the use under the condition of long-time and varying environment of this known value can keep stable with known value.In the open method of attachment scope of using electroconductive binder, any joint with following characteristics it is generally acknowledged it all is satisfactory, promptly this joint is 90% in relative humidity (RH), temperature be under 60 ℃ the condition after 1000 hours, the mean value of the variation of contact resistance value is less than the scope of about 20-25%, preferably less than 15%.Here employed term " moisture resistance tackiness agent " and " moisture resistance electrically contacts " are meant a kind of like this electroconductive binder, promptly utilize the made joint of this electroconductive binder, in relative humidity is 90%, temperature is under 60 ℃ the test conditions, after 1000 hours, have stable contact resistance value, this resistance change scope on average is no more than about 25%.

The factor that influence connects interface place electroconductibility is whether to have the existence non-conductive or oxide on surface that resistance is electric, and this oxide on surface is exposed and contacts with ambient air and moisture.In the method for being welded to connect, can remove the oxide compound at interface place between the lead that is surrounded by scolder and the scolder itself widely with welding agent, this welding agent can react with oxide compound, and can be, but also when solder cools, air and the moisture that connects the turnover of interface place can be separated effectively with this oxide removal.In the electroconductive binder method of attachment, in solidification process, need not use welding agent, therefore people wish that this tackiness agent comprises the composition that can reduce the oxide on surface negative effect, and need not before forming joint, to adopt corrosion clean-out system or other treatment process to handle the surface that will connect, as the lead of plumbiferous electronic component.

Though known is that the initial volume resistance rate of the electroconductive binder of major ingredient can meet the demands with silver, yet because the existence of non-conductive lead/tin-oxide, this tackiness agent is easy to increase the resistivity at the interface place of outer plating scolder lead.Therefore the electroconductive binder and the contact resistance value of plating outward between the scolder lead may produce sizable variation in time, particularly under the very big envrionment conditions of humidity.Resistance value in the above-mentioned joint is under the envrionment conditions that is in high temperature and big humidity continuously.Resistance value in the above-mentioned joint is to responsive especially under the environment that is in high temperature and big humidity continuously.Because list or the bi-component polymeric carrier of above-mentioned use in general electroconductive binder can be penetrated in the moisture naturally, therefore company's head made from this tackiness agent can be subjected to the disadvantageous effect of moisture to a certain extent.Though can adapt to the cumulative contact resistance by design circuit, yet the resistance change of bringing in time can have a negative impact to the whole electrical property of circuit.It is generally acknowledged, be penetrated into the metal generation oxidation that moisture in the carrier in the joint of being made by electroconductive binder can make the interface place that is positioned at electroconductive binder and element lead, formed non-conductive oxide compound then can make resistance strengthen.

Known electroconductive binder composition generally comprises polymkeric substance or the carrier that is filled with conductive particle in the prior art.Such as, a kind of mixture has been described in the US4880570 patent, this mixture comprises with Resins, epoxy being the tackiness agent of major ingredient, contact substance with and shape can make steric hindrance disturb minimum and the conductive particle of electroconductibility can be provided; Described a kind of mixture of organic medium in the US4859364 patent, being filled with particle diameter and being outer metallic particle and the particle diameter that is coated with conduction that is no more than 1 micron in this organic medium is the conductive particle of 0.3-1.0 micron; A kind of light perception resin polymkeric substance has been described in the US4859268 patent, the mixture of softening agent and spherical conductive particle, a kind of binder layer has been described in the US4814040 patent, include the conductive particle of certain particle diameter in this binder layer, promptly by utilizing this particle of hot pressure method can pass resistive layer and entering into metal pattern; In the US4732702 patent, described a kind of resin compound, be filled with conductive metal powder in this resin or plate the inorganic insulation powder of conducting film outward; The mixture of a kind of plastics, rubber or resin has been described in the US4716081 patent, wherein also be filled with silver plated metallic particles, a kind of thermoplastic synthetic rubber mixture has been described in the US4701279 patent, be filled with metallic particles in this rubber, in the US4696764 patent, describe a kind of resin compound, in this resin, be filled with abrasive material and conduction molecule; Having described a kind of in the US4624801 patent is the mixture of polymers of major ingredient with the polyester urethanum, and this polymkeric substance mixes with closed different oxygen hydrochlorate and is filled with conductive particle; Described a kind of Resins, epoxy in the US4747968 patent, stiffening agent and metallic silver particles mixture have been described a kind of vinylformic acid in the US4564563 patent, the mixture of carboxylation ethene and epoxy polymer, and this polymkeric substance is filled with metallic silver particles; In the US4566990 patent, describe a kind of mixture of thermoplastic solidified polymeric, be filled with the fiber of tinsel and conducting metal or outer metallizing in this polymkeric substance.

Generally speaking, the polymer system electroconductive binder that is filled with silver has good performance in suitable high temperature range, but under bigger humidity condition, at the interface place of tackiness agent and conductor wire, this adherent performance is then relatively poor.Be in the following time of condition of humidity greatly when for a long time, the resistance between the interface place is usually unstable, promptly can increase greatly.Though still can works better under the situation that the resistivity of many circuit in one or more joints increases greatly, the susceptibility of humidity still is considered to limit electroconductive binder widespread use factor more in rigidity and flexbile base.

According to top described, the object of the present invention is to provide a kind of electroconductive binder, the serviceability of this electroconductive binder is improved, particularly under the bigger situation of high temperature and/or humidity, when being used for that salient point is contacted, when surface immobilising device and other electron component are connected on the substrate, has better characteristic.Above-mentioned electronic component adopts plain metal coating, as weld tabs and tin sheet.

Another object of the present invention is to provide a kind of electrically conductive cements, in this tackiness agent,, make carrier amass the form that contraction helps conductive contact by improving the electroconductibility between the particle and contacting forming airtight surface between filler and the surface to be connected.

The present invention also aims to provide a kind of electroconductive binder, this tackiness agent comprises the conductive particle that is scattered in the carrier, this conductive particle has surface property, and its particle diameter helps to form owing to carrier in solidification process shrinks the filler particles that brings and contacts with the resistance to air loss between the surface to be connected is surperficial.

The invention provides a kind of electroconductive binder, this tackiness agent is used for bonding between the adhesive surface and forms between them electrically contacting, and this tackiness agent comprises a kind of mixture, this mixture contain can be in bonding carrier the dispersive filler.Above-mentioned carrier volumetric shrinkage in process of setting, this carrier has such content, when carrier is this content, described mixture is connected on the substrate effectively.Above-mentioned filler comprises the conductive particle of certain content, and this particle has such structure, when particle has this structure, helps to form moisture resistance and electrically contact in the carrier process of setting.

The present invention also provides a kind of method of making the moisture resistance conductive contact, its step is included in a kind of mixture of surperficial spreading, this mixture comprises bonding carrier and filler, this carrier volumetric shrinkage in process of setting, above-mentioned filler comprises the conductive particle of certain content, and its structure constitutes and helps to form moisture resistance with substrate and electrically contact.

The invention provides a kind of electroconductive binder, this electroconductive binder comprises coagulable polymer support, this carrier be in do not solidify and curdled appearance between the time volumetric shrinkage, its shrinkage value is greater than 6.8%, preferably between 7.5%-65%.Above-mentioned electroconductive binder also comprises filler, and this filler comprises conductive particle, and this conductive particle helps to form moisture resistance and electrically contacts in the carrier process of setting.

Do not limited though here do not want to move with any special invention theory or pattern, it is generally acknowledged use be in non-solidify and curdled appearance between and have volume shrinkage characteristic and its shrinkage value and surpass about 6.8% carrier or tackiness agent and can make filler particles reach good degree of compactness.Above-mentioned filler particles is scattered in the carrier, and the structure that has suitable content and be fit to, thereby can improve the electrically contacting each other of above-mentioned filler particles, and makes surface to be connected form the gas barrier layer.Generally also think, in process of setting, when if pressure is enough big, the carrier contraction can make its internal particle be in pressured state, thereby above-mentioned particle is in contact with one another, but also the particle that is in interface place between tackiness agent and the surface is linked together, and penetrate and to be present in lip-deep impurity and non-conductive oxide compound.The relative carrier of above-mentioned particle keeps certain content, and has structured surface features and such size, promptly when the volumetric shrinkage of carrier and the pressure that produces, uses this grain diameter to help to form from the teeth outwards to be tightly connected in being subjected to process of setting.Thereby make when the conductive particle of the adhesive surface projection of solidifying is exposed to the outside when utilizing mechanical means that joint is drawn back at the interface place, believe that the airtight joint with surface can be verified.And moisture resistance electrically contacts the result who is pressed in the granuloplastic gas barrier layer of projection of conductive line surfaces just because of above-mentioned.

Employed carrier can be to produce any material effectively shrink and be filled with conductive particle when solidifying in the tackiness agent of the present invention, and this material has enough cohesive strengths and bond strength to form the mechanically joint of dependable performance simultaneously.Above-mentioned carrier can comprise with the solvent being the polymer system of major ingredient, maybe may form the mixture of two kinds of polymer supports, wherein a kind of carrier has high volume shrinkage characteristic, and another kind of carrier has low volume shrinkage characteristic, the weight percent of these the two kinds of carriers in this mixture can change, effectively to make this mixture have volume shrinkage characteristic in the scope.

In one embodiment of the present of invention, conductive filler granule is an agglomerate, its particle diameter is in 10.6 microns-Yue 2.00 microns distribution range (median size is 4.5 microns), this particle diameter has coarse outside surface, feature is to have many recesses and carinate interface or salient angle, and its length and width and high ratio are about 1: 1: 1.When the volumetric shrinkage of tackiness agent, the surface irregularity feature of believing this agglomerate helps to form moisture resistance and electrically contacts and infiltrate in the oxide on surface or impurity on the conductive line surfaces in the adhesive process.Electrically contact because the barment tag of above-mentioned agglomerate can participate in as forming moisture resistance between the lead of particle, electronic component and the on-chip joining region, therefore this agglomerate is suitable electron carrier.In another embodiment, moisture resistance electrically contacts and can make with other particle that is called " surface seepage particle ", so that comprise the particle of solid particulate and outer metallizing among the application, these particles have the characteristic similar to above-mentioned agglomerate, comprise its particle diameter and rough surface features.

In illustrated embodiments, carrier comprises a kind of mixture and certain non-activated thinner of being made up of two kinds of Resins, epoxy, wherein the ratio of every kind of composition be adjustable to make carrier be in non-solidify and curdled appearance between the volumetric shrinkage value greater than about 6.8%, be preferably 7.5%-65%.

If desired, can add the wetting agent of certain content to improve non-wetting capacity (its content generally accounts for the 2-5% of carrier) of solidifying epoxy resin composition in the spreading process.

In above-mentioned most preferred embodiment, the conductive particle weighting agent is the mixture of a kind of silver strip, silver powder and silver-colored agglomerate.This agglomerate is for having erose particle, and this particle has many surfaces depression, and they form the salient angle or the ridge of many coarse seamed edges, and above-mentioned particulate length and width and high ratio are about 1: 1: 1.Because the silver oxide insulation oxide of other material relatively can conduct electricity, so preferred here silver-colored particle and silver-plated particle; Under these conditions, gold, palladium and other precious metal also have the performance of good this respect, but it involve great expense.Nickel has been proved to be under high temperature and high humidity has satisfactory stability, yet its initial resistance is higher.When forming adhint, under the content situation that is fit to, above-mentioned silver-colored agglomerate can be penetrated in the non-conductive oxide compound on the lead of surface to be connected and lead plating/tin.Generally speaking, the content of filler particles accounts for about 60%-90% of epoxy resin composition/conductive filler granule composition total weight, preferably is approximately 75%.

Above-mentioned and other the purpose of the present invention and the further scope of application can contrast accompanying drawing and obtain understanding from following detailed.

Fig. 1 (prior art) is a form, and expression is by the moiety of prior art, is the increase of contact resistance under 90% the environment in relative humidity.

Fig. 2 is a Photomicrograph that has amplified 5000 times the silver-colored agglomerate that is adopted in the moiety of example 2, and it represents the feature of many uneven surfaces.

Fig. 3 A is the moiety of an expression by example 2 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity, and here, lead will clean it with acetone before joint.

Fig. 3 B is another expression by the moiety of example 2 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity, here, will clean lead with mineral acid before forming joint.

Fig. 4 is the moiety of an expression by example 3 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Fig. 5 is the moiety of an expression by example 4 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Fig. 6 is the moiety of an expression by example 5 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Fig. 7 is the moiety of an expression by example 6 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Fig. 8 is the moiety of an expression by example 7 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Fig. 9 is the moiety of an expression by example 8 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Figure 10 is the moiety of an expression by example 9 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Figure 11 be an expression by example 10 moietys of the present invention, be the form of the stability of contact resistance under 90% the environment in relative humidity.

Figure 12 is the moiety of an expression by example 11 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Figure 13 is the moiety of an expression by example 12 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Figure 14 is the moiety of an expression by example 13 of the present invention, is the form of the stability of contact resistance under 90% the environment in relative humidity.

Under unfavorable condition of work, when particularly under the condition of high temperature and high humility, having the electroconductive binder of superior performance, must consider many factors in development. Because the situation that moisture infiltrates all can take place all polymer supports to a certain extent, so the conductive particle filler will have such character, and namely formed non-conductive oxide maintains minimum under the wet environment being in for a long time. In addition, carrier should have following characteristic, namely not only will strengthen the electric conductivity at adhesive and lead interface place, but also wants the conductibility between the conductive particle in the reinforcer; Other noble metal and nickel meets this requirement and preferably selects silver-colored particle or silver-plated granular filler, although also can be fit to adopt.

Silver-colored agglomerate, silver-colored particle, silver strip, silver powder and the such filler of silver-plated particle have been provided in the of the present invention various constituents that provide below. The feature of above-mentioned silver-colored agglomerate is to have irregularly shapedly, and its surface has many depressions, has formed chimb or ridge between these recess. The length and width of above-mentioned agglomerate and be preferably at high proportion 1: 1: 1, believe that so above-mentioned agglomerate just can play force vector, these force vectors in addition when being in the environment of high temperature and high humidity, also can form gas-insulated layer at connection interface place, and can penetrate existing oxide on the joint face, make it keep stable electrically contacting. Here employed plating particle is silver-plated non-conductive inorganic spheroid and is coated with outer silver-plated base metal and the non-conductive inorganic spheroid of nickel. The closely knit phenomenon that forms along with the volume contraction of polymer support, believe that above-mentioned agglomerate forms the initiating electron circulation passage with outer plating particle through direct surface in the carrier after solidifying with contacting of interior surface particle, and above-mentioned agglomerate and outer plating particle contact with the conductive line surfaces of connector, are penetrated into wherein simultaneously. For the silver-colored particle in granule footpath, it is characterized by Powderedly here, it will have Be beneficial to the formation of the conductive channel between large-size particles. Along with carrier bulk shrinks and the generation internal pressure, above-mentioned little powder particle, as in bigger agglomerate or particle, can send out single or in groups and be penetrated in any oxide or surface impurity that the interface place exists between the adhesive of junction and element lead.

Although have said structure and have the moisture resistance electric contact with continuous an amount of agglomerate and the powder particle together of described carrier, yet find sheet or the crystalline conductive particle of sheet also of great use. Sheet-like particle be exactly its gauge greatly (namely a grade or the order of magnitude) less than the particulate of its length and width. If content is fit to, sheet-like particle then can trend towards overlapping or front and back overlap mutually, thereby has strengthened the electric conductivity of this system.

In order to make conductive particle filler inside closely knit, carrier should have the volume shrinkage characteristic greater than about 6.8%. Other characteristic of carrier should comprise good cementability, wettability and good operating characteristics. Because many electroconductive binders are by screen printing, mould printing or similar techniques spreading, therefore the solidification aggregation carrier should not have certain viscosity, thereby can make the electroconductive binder of finally making be fit to adopt said method to come spreading. The rheological behavior of carrier should be conducive to usually employed mould printing, plate printing or pneumatic deposition process when the spreading electroconductive binder, and its viscosity that is fit to can be at 50000-25000(PS) in the scope.

Following embodiment is the representative moiety with electroconductive binder that moisture resistance electrically contacts.

The linear shrinkage value can be determined by following mode: spreading one rectangular not solidified tackiness agent in the plane solidifies it, the function of shrinkage value as not solidified and the lineal measure of solidifying.Volume shrinkage characteristic between not solidified and the tackiness agent that solidifies is determined by following formula.

Pu is under the room temperature situation for not solidified (carrier) Resins, epoxy dissolved concentration, and by the weight W of the container that Resins, epoxy is housed with known volume V, and the heavy W of known empty receptacle determines as follows:

Pu=(W-w)/V formula 1

Adopt METTLER density measurement utensil E-210250 and OHAUS precision balance 160D at room temperature to determine the concentration pu of the Resins, epoxy that solidifies according to Archimedes' principle (ASTMC693).The dry weight of determining the Resins, epoxy sample of air set is A, and its weight with concentration known pl in liquid is p, and the concentration pc of the Resins, epoxy that then solidifies is:

Pc=(A/P) the pi formula 2

By utilizing the determined not solidified and Resins, epoxy volume that solidifies of the pu value that draws above, just can determine the volumetric shrinkage value Vs of not solidified and the Resins, epoxy that solidifies.Determine the volume Vu of not solidified Resins, epoxy by the weight W of measuring not solidified Resins, epoxy sample.Can determine by following formula:

Vu=Ww/pu formula 3

By treatment process given below Resins, epoxy is solidified then, and measure the weight W c of this sample that solidifies.Calculate the volume Vc of the Resins, epoxy that solidifies by following formula.

Vc=Wc/pc formula 4

Follow the percentage value Vs that calculates volumetric shrinkage by following formula:

Vs=[(Vu-Vc)/and Vu] (100) formula 5

Embodiment 1

As being the exemplary that contact resistance changes under 90% condition in relative humidity, its electroconductive binder is by Emerson ﹠amp; Cuming of Lexingbon, MA produces, and it sells the trade mark is " AMICON ^TMCSM-933-65-1 ".The explanation that provides according to producer, this electroconductive binder is used for connecting one 68 leg surface immobilising device on test circuit, [68-Pin swrface-mount device(SMD)], two 44 legs surface immobilising device and 10 resistance string that are cascaded (resistor series string), and this tackiness agent placed 10 minutes under 140 ℃ of temperature.Leg in each surperficial immobilising device is series connected by the resistance element in the surperficial immobilising device and total contact resistance, and above-mentioned total contact resistance value is to draw from total series impedance that the total resistance value of measuring deducts the device inner member.Equally, the resistance value of resistance string also can deduct the aggregate-value of the resistance that constitutes resistance string and draws from total series impedance, thereby draws the accumulation contact resistance value.When testing with pilot circuit, the resistance value of the inner member in the surperficial immobilising device and each resistance in the resistance string in probe temperature and humidity range, all are stable.In room temperature and relative humidity is 90%, temperature be the initial contact resistance value (ohm) measured under 60 ℃ the test condition as shown in Figure 1.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, to place after 15.5,24,39 and 63 hours, respectively resistivity is measured again.As shown in Figure 1, all contact resistance ohmic values increase under the condition of relative humidity 90% in time, corresponding 1000 hours estimated value shows for 68 legs surface immobilising device and 2 44 leg surface immobilising devices, contact resistance value significantly increases, and for resistance string, contact resistance value then increases less.

Can draw after the data that provide from analysis chart 1, the contact made from the conductive adhesion in the prior art, under the bigger condition of relative humidity through after for a long time, its resistance can significantly increase.

Embodiment 2

Prepare a kind of electroconductive binder with a kind of conductive filler material that comprises 3 kinds of silver-colored particle A, B, C.Particle is a silver strip, and its Fei Xier diameter of particle (FSSS) is the 0.90-1.30 micron, and vibration density (measuring with the Tap-Pak volumeter) is 0.3-3.5g/cc, and it is 30-35g/in that Scott is looked (Scott apparent) density ³, surface-area is 0.3-0.6m ²/ g, size distribution is 90%＜14.000 micron, 50%＜7.00 micron, 10%＜2.00 micron.The particle size distribution data that here provides is measured with Leeds and Northrop Microtrac.The particle A that is fit to is " silver strip #53 ", and this silver strip can have been bought from the electronic material branch office of the Metz Usiminas that is positioned at South Ploir field.

Particle B is silver-colored agglomerate, and the Fei Xier diameter of particle (FSSS) of this agglomerate is 0.6 micron, and it is 16.7g/in that vibration density (measuring with the Tap-Pak volumeter) is looked (Scott appaTent) density for the 1.85g/cc Scott ³, surface-area is 1.62m ²/ g, size distribution is 100%＜10.6 micron, 90%＜8.10 micron, 50%＜4.4 micron.10%＜1.40 micron, median size is 4.5 microns.Suitable particle B can select " SPS-100 silver powder ", and this powder can have been bought from Metz Usiminas.This agglomerate shown in Fig. 2 Photomicrograph has many coarse surface characteristic.

Particle C is a silver powder, and its Fei Xier diameter of particle (FSSS) is 0.7 micron, and vibration density (measuring with the Tap-Pak volumeter) is 2.75g/cc, and it is 17.5g/m that Scott is looked (Scott a pparent) density ², surface-area is 1.84m ²/ g, size distribution is 100%＜5.25 micron, 90%＜3.16 micron, 50%＜1.25 micron.The particle C that is fit to can buy from Metz Usiminas for " a thin silver last S-ED ".

Particle A, B, C press column weight amount percentage mix, and particle A accounts for 40%, and particle B accounts for 30%, and particle C accounts for 30%, thus form and carrier blended argent filler mutually.

Carrier is for comprising two kinds of Resins, epoxy, the polyblend of Resins, epoxy A and Resins, epoxy B.Resins, epoxy A is a bisphenol F epoxy resin, as " Aratronic 5046 ", and a kind of Bisphenol F diglycidyl ether, its viscosity is 1400CPS in the time of 25 ℃.Above-mentioned Resins, epoxy can have been bought from CibaGeigy company.Resins, epoxy B is liquefied phenol novolac epoxy resin (phenol epoxy novolac resin), as Quatrex 2010, a kind of phenol novolac epoxy resin, this resin has the higher relatively viscosity of 25000-45000CPS in the time of 52 ℃, above-mentioned resin can be from being positioned at MI, and the Dow chemical company of Midland has bought.

Can also comprise the common stiffening agent as imidazoles in the polymer support, for example the trade mark is " CURIMID ^TM-CN ", be positioned at MA, N-(α-cyanoethyl that the Poly Organix company of New buport produces)-the 2-ethyl, 4-methylimidazole.

Can also comprise coupler or wetting agent in the polymer support.To improve the wet performance of unset material.Typical coupler is certain oily propoxy-Trimethoxy silane of γ-shrink.Above-mentioned coupler can have been bought for the Vnion Carbide company of " A187 " by selling the trade mark.The another kind of auxiliary that can add in polymer support of the present invention is γ-Ding lactones, and this auxiliary can be from being positioned at WI, and the Aldrich chemical company of Milwaukee has bought, and its effect is to regulate viscosity as thinner.

The conductive adhesion agent composition prepares by following moiety:

Every batch of consumption-weight percent of moiety (%)

(standard weights unit)

Resins, epoxy A 8.275

Resins, epoxy B 8.275

Stiffening agent 3.973

Thinner 1.985

Coupler 0.993

Resins, epoxy gross weight=23.5%

Particle A 30.600

Particle B 22.950

Particle C 22.950

Silver content gross weight=76.5%

Given here 76.5% silver content value is an optimum value in the general use technology, as in stencilization, and screen printing, the tampo printing, it is medium to spray the spreading method.If above-mentioned numerical value is lower than 74%, the electroconductibility of then above-mentioned conductive adhesion agent composition under various test conditions presents instability, and resistance value increases an order of magnitude.If above-mentioned numerical value is higher than 78%, although above-mentioned conductive adhesion agent composition is fit to spraying spreading, then viscosity is excessive when using stencilization and screen printing to come spreading.

The volumetric shrinkage pH-value determination pH of above-mentioned polymer support is 17%.In test for the first time, lead at first adopts acetone to clean.The mixture of above-mentioned moiety is used for connecting 68 legs surface immobilising device (SMD), 44 legs surface immobilising device and the resistance string that is connected in series in each circuit of 6 test circuits (test circuit 1-6) described in the example 1.

In room temperature and relative humidity is 90%, and temperature is under 60 ℃ the test condition, contact resistance to be tested, and its measured value as shown in Figure 3A.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, to measure resistivity respectively." growth percentage " shown in the hurdle, is under 90% condition in relative humidity (%) in Fig. 3 A, after 1002 hours, surpasses 11% except a set of contact resistance ohmic value increases, and all other contact resistance ohmic values change very little.

In test for the second time, at first clean with the lead of mineral acid to above-mentioned device, make joint with the moiety of present embodiment in a manner described then.In room temperature and relative humidity is 90%, and temperature is under 60 ℃ the test condition, contact resistance to be measured, and its measured value is shown in Fig. 3 B.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, 14.5,117.5,149,297 and after 969 hours, respectively resistivity is measured.Shown in " increase percentage " hurdle shown in Fig. 3 B, be under 90% the condition in relative humidity, after 969 hours, except ohm increased value of a set of contact resistance only surpasses 12%, all other contact resistance ohmic values change very little.

Embodiment 3

Adopt the conductive particle filler of 3 kinds of silver-colored particle A, B, C to prepare electroconductive binder.Identical with described in the example 2 of above-mentioned particle A, B, C, particle A, B, C account for 40% by particle A, and particle B accounts for 30%, and particle C accounts for 30% weight percent to be mixed equally, forms and carrier blended filler mutually.

Comprise a single Resins, epoxy in the carrier, this Resins, epoxy is liquid bisphenol A Resins, epoxy, and as " Quantrex 1010 ", this resin its viscosity in the time of 25 ℃ is 11000-14000CPS, can buy from Dow chemical company.

Can also comprise stiffening agent [N-(2-cyanogen (ethyl)-2-ethyl, 4-methylimidazole] in the polymer support, the sweet propoxy-Trimethoxy silane of γ-shrink, and thinner γ-Ding lactones.

Electroconductive binder is by the preparation of following moiety:

Every batch of consumption-weight percent of moiety (%)

(standard weights unit)

Resins, epoxy A 16.55

Stiffening agent 3.97

Coupler 0.99

Thinner 1.99

Resins, epoxy gross weight=23.50%

Particle A 30.600

Particle B 22.950

Particle C 22.950

Silver content gross weight=76.5%

The volumetric shrinkage value of above-mentioned polymer support is 13%, and carrier is used for connecting 68 legs surface immobilising device (SMD), 44 legs surface immobilising device and the resistance string that is connected in series in each circuit of two test circuits (test circuit 1-2) described in the example 1.In room temperature and relative humidity is 90%, and temperature is under 60 ℃ the test condition, contact resistance to be measured, and its measured value as shown in Figure 4.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, 15,65 and 141 hours after again resistivity is measured respectively.Shown in " growth percentage " hurdle among Fig. 4, be under 90% the condition, after 141 hours, to surpass 2% in relative humidity except there being two set of contact resistance ohmic values to increase, the ohmic value of all other contact resistances changes very little.

Embodiment 4

Adopt the conductive particle filler of two kinds of silver-colored particle A and C to prepare electroconductive binder, that is adopted in above-mentioned silver-colored particle A and C and the example 2 is identical.

Particle A and C need to mix mutually as following weight percent, and promptly particle A accounts for 40%, and particle C accounts for 60%, form and carrier blended filler mutually.

Carrier is for containing two kinds of Resins, epoxy, i.e. the mixture of Resins, epoxy A and Resins, epoxy B.Resins, epoxy A is a bisphenol F epoxy resin, and as " Aratronic 5046 ", Resins, epoxy B is the liquefied phenol novolac epoxy resin, as Quatrex 2010.

Polymer support also can comprise stiffening agent [as the N-2(2-cyanoethyl)-the 2-2 base, 4-methylimidazole], coupler (γ-Racemic glycidol third fluorine-based silane) and thinner (as γ-Ding lactones).

Electroconductive binder is by the preparation of following moiety:

Every batch of consumption-weight percent of moiety (%)

(standard weights unit)

Resins, epoxy A 8.21

Resins, epoxy B 8.21

Stiffening agent 3.94

Thinner 0.66

Coupler 0.99

Resins, epoxy gross weight=22.0%

Particle A 31.20

Particle C 46.80

Silver content gross weight=78.0%

The volumetric shrinkage value of above-mentioned polymer support is 10%, and this carrier is used for connecting 68 legs surface immobilising device, 44 legs surface immobilising device and the resistance string that is connected in series in each circuit of 6 test circuits (test circuit 1-6) described in the example 1.In room temperature and relative humidity is 90%, and temperature is under 60 ℃ the test condition, contact resistance to be measured, and its measured value as shown in Figure 5.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, 62,136, respectively resistivity to be measured after 1073 hours.Shown in listed among Fig. 5 " growth percentage " hurdle, be under 90% the condition, after 1598 hours, to surpass 19% in relative humidity except only there being a set of contact resistance ohmic value to increase, the ohmic value of all other contact resistances changes very little.

Embodiment 5

Adopt the conductive filler material of three kinds of silver-colored particle A, B and C to prepare electroconductive binder, the particle A described in above-mentioned silver-colored particle A, B and C and the embodiment 2, B is identical with C.Particle A, B and C mix by following weight percent, and promptly particle A accounts for 40%, and particle B accounts for 30%, and particle C accounts for 30%, thereby forms and carrier blended filler mutually.Carrier comprises a kind of composition of single Resins, epoxy/solvent, and this Resins, epoxy is bisphenol A epoxide resin, and as " EPONOL(R) 53-BH-35 ", a kind of high-molecular weight Resins, epoxy can have been bought from the shell chemical company of the Hoastom that is positioned at the TX state.In the product type that this producer provided, Resins, epoxy accounts for 35% of product population, the solution that remaining composition is served as reasons and contained 75% methyl ethyl ketone (MEK) and contain 25% methyl proxitol (PGME) formation.Before the electroconductive binder of preparation example 5, can remove methyl ethyl ketone (MEK) and methyl proxitol (PGME), be changed to 2-butoxy acetic acid ethyl ester as having bought from Aldrich chemical company.

Prepare conductive adhesion agent composition of the present invention by following moiety:

Every batch of consumption-weight percent of moiety (%)

(standard weights unit)

Resins, epoxy 12.921

Solvent 23.996

Resins, epoxy gross weight=36.917%

Particle A 25.233

Particle B 18.925

Particle C 46.80

Silver content gross weight=63.083%

The volumetric shrinkage value of above-mentioned polymer support is 65%, and this carrier is used for connecting 68 legs surface immobilising device, 44 legs surface immobilising device and the resistance string that is connected in series in each circuit of 6 test circuits (test circuit 1-6) described in the example 1.In room temperature and relative humidity is 90%, and temperature is under 60 ℃ the test condition, contact resistance to be measured, and this measured value as shown in Figure 6.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, 6,13,349 and measure resistivity after 1530 hours respectively; Shown in listed " growth percentage " hurdle of Fig. 6, be 90% in relative humidity, after 1530 hours, except the rate of increase that a set of contact resistance is only arranged surpasses 10%, the ohmic value of all other contact resistances changes very little.

Embodiment 6

Adopt three kinds of silver-colored particle A, the filler of B and C prepares electroconductive binder, above-mentioned particle A, and used particle A in B and C and the example 2, B is identical with C.Particle A falls C and mixes as following weight percent, and promptly particle A accounts for 40%, and particle B accounts for 30%, and particle C accounts for 30%, thereby forms and carrier blended filler mutually.

Carrier comprises the composition of a single Resins, epoxy/solvent.This Resins, epoxy is novolac epoxy, and as " Quatrex 2010 ", a kind of phenol novolac epoxy resin has the high relatively viscosity of 25000-45000CPS in the time of 25 ℃, can buy from Dow chemical company.Solvent 2-(2-ethoxy ethoxy) ethyl acetate can be from being positioned at the NY state; The acetic ester of trade mark for " Carbitol " bought by the Eastman Kodak company of Rochester.Above-mentioned solvent also is glycol ether-ethyl ethyl acetate.In polymer support, can also comprise stiffening agent (as N-(2-cyaniding base)-2-ethyl, 4-methylimidazole) and coupler (as γ-Racemic glycidol propoxy-Trimethoxy silane).

Prepare electroconductive binder by following moiety:

Every batch of consumption-weight percent of moiety (%)

(standard weights unit)

Resins, epoxy 14.79

Solvent 6.34

Stiffening agent 1.18

Coupler 0.89

Resins, epoxy gross weight=23.20%

Particle A 30.72

Particle B 23.04

Particle C 23.04

Silver content gross weight=76.8%

The volumetric shrinkage value of above-mentioned polymer support is 25%, and this carrier is used for connecting 68 legs surface immobilising device, 44 legs surface immobilising device and the resistance string that is connected in series in each circuit of 6 test circuits (test circuit 1-6) described in the example 1.In room temperature and relative humidity is 90%, and temperature is under 60 ℃ the test condition, contact resistance to be measured, and this measured value as shown in Figure 7.In relative humidity is 90%, and temperature is under 60 ℃ the test condition, through 14,16 and 1025 hours after, test resistance rate respectively.Shown in listed " growth percentage " hurdle of Fig. 7, be 90% in relative humidity, after 1025 hours, the ohmic value of all contact resistances changes very little.

Embodiment 7

Adopt three kinds of silver-colored particle A, the filler of B and C prepares electroconductive binder, above-mentioned particle A, and the particle A that B and C and example 2 are adopted, B is identical with C.Particle A, B, C mixes by following weight percent, and particle A accounts for 40%, and particle B accounts for 30%, and particle C accounts for 30%, thereby forms and carrier blended argent filler mutually.

Carrier comprises two kinds of Resins, epoxy, i.e. a kind of mixture of the composition of Resins, epoxy A and Resins, epoxy B.Resins, epoxy A is a bisphenol A epoxide resin, " Eponol 53 " as described above, and Resins, epoxy is the liquefied phenol novolac epoxy resin, as above-mentioned " Quatrex 1010 ".

Polymer support can also comprise stiffening agent I and II.The stiffening agent I is a polyoxypropylene diamine, and this stiffening agent can have been bought from Texaco chemical company, and selling the trade mark is " Jeffamine D-230 ".The stiffening agent II is a triethylene glycol diamine, and this stiffening agent can have been bought from Texaco chemical company, and selling the trade mark is " Jeffamine EDR148 ".

Polymer support can also comprise that accelerator is to improve coagulation efficacy.The accelerator such as the aliphatic amine mixture that are fit to, can buy from Texaco chemical company, sell the trade mark and can also comprise adhesion promotor for " 399 " above-mentioned polymer support, as poly-(propylene oxide) triamine of glycerine (base), it can have been bought from Texaco chemical company, and selling the trade mark is " Jeffamine T-5000 ".

Prepare electroconductive binder by following moiety:

Every batch of consumption-weight percent of moiety (%)

(standard weights unit)

Resins, epoxy A 13.50

Resins, epoxy B 8.94

Stiffening agent I 2.59

Stiffening agent II 0.36

Accelerator 0.27

Bonding accelerator 1.34

Resins, epoxy gross weight=27.00%

Particle A 25.20

Particle B 21.90

Particle C 21.90

Silver content gross weight=73.00%

The volumetric shrinkage value of above-mentioned polymer support is 19%, and this carrier is used for connecting 68 legs surface immobilising device, 44 legs surface immobilising device and the resistance string that is connected in series in each circuit of 6 test circuits (test circuit 1-6) described in the example 1.In room temperature and temperature is 60 ℃, and relative humidity is under 90% the test condition, contact resistance to be measured, and this measured value as shown in Figure 8.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, through 15,19 and 981 hours after measure resistivity respectively; Shown in listed " growth percentage " hurdle of Fig. 8, be 90% in relative humidity, after 1598 hours, except a set of contact resistance value rate of increase surpasses 8%, the ohmic value of all other contact resistances changes very little.

Embodiment 8

Adopt two kinds of conductive particles, promptly the conductive particle filler of particle A and D prepares electroconductive binder.Particle A used in particle A and the example 1 is identical.Particle D is silver-plated nickel particle, and its median size is 28 μ, and actual particle size is distributed as 90%＜48.19 micron, 50%＜27.97 micron and 10%＜12.36 micron.Particle D can select for use and be positioned at New York 07481(201-891-7976), Wyckof, 681LawLins road INCO company, the particle that Novamet specialty products company produces.

Particle A and D wish to press column weight amount percentage mix, and promptly particle A accounts for 80%, and particle D accounts for 20%, thereby have formed and carrier blended filler mutually.

Carrier is for containing two kinds of Resins, epoxy, the mixture of Resins, epoxy A and Resins, epoxy B.Resins, epoxy A is a bisphenol F epoxy resin, and as " Aratronic 5046 ", Resins, epoxy B is the liquefied phenol novolac epoxy resin, as " Quatrex 2010 ".

Polymer support can also comprise stiffening agent [as the N-(2-cyanoethyl)-the 2-ethyl, 4-methylimidazole] and coupler (γ-Racemic glycidol propoxy-Trimethoxy silane).

Prepare electroconductive binder by following moiety:

Every batch of consumption-weight percent of moiety (%)

(standard weights unit)

Resins, epoxy A 7.50

Resins, epoxy B 7.50

Stiffening agent 3.60

Coupler 0.90

Resins, epoxy gross weight=19.5%

Particle A 64.40

Particle B 16.10

Silver content gross weight=80.5%

The volumetric shrinkage value of above-mentioned polymer support is 7.6%, and this carrier is used for connecting 68 legs surface immobilising device, 44 legs surface immobilising device and the resistance string that is connected in series in each circuit of 6 test circuits (test circuit 1-6) described in the example 1.In room temperature and relative humidity is 90%, and temperature is 60 ℃, test condition under, contact resistance is measured, this measured value as shown in Figure 9.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, through 119,503 and 1146 hours after measure resistivity.Shown in listed " growth percentage " hurdle of Fig. 9, be 90% in relative humidity, after 1146 hours, except a set of contact resistance value rate of increase surpasses 15%, the ohmic value of other all contact resistances changes very little.

Embodiment 9

Adopt two kinds of conductive particles, promptly the conductive particle filler of particle A and E prepares electroconductive binder, and above-mentioned particle A is identical with employed particle A among the embodiment 1.Particle E is silver-plated particle, and this particle contains and is about the 32%(weight percent) silver, this particulate Scott volume density is 3.66g/in ³, surface-area is 0.22m ²/ g, powder resistivity are 0.4(m ohmcm), median size is 21 μ, actual particle size is distributed as 90%＜29.3 micron, 90%＜19.5 micron and 10%＜13.9 micron.Particle E can select for use and sell the trade mark is " Cordueto-O-Fil silver nickel ", is positioned at the particle of the Potter Industrial Co., Ltd production of NJ Carlstadf.

Particle A and E mix by following weight percent, and particle A accounts for 80%, and particle E accounts for 20%, thereby form and carrier blended filler mutually.

Mainly comprise in the carrier and contain two kinds of Resins, epoxy, be i.e. the mixture of Resins, epoxy A and Resins, epoxy B.Resins, epoxy A is a bisphenol F epoxy resin, and as " Aratronic 5046 ", Resins, epoxy B is the liquefied phenol novolac epoxy resin, as " Quatrex 2010 ".

Can also comprise in the polymer support stiffening agent [as the N-(2-cyanoethyl)-the 2-ethyl, 4-methylimidazole] and coupler (as γ-Racemic glycidol propoxy-Trimethoxy silane).

Prepare electroconductive binder by following moiety

Every batch of consumption-weight percent of moiety (%)

(standard weights unit)

Resins, epoxy A 7.50

Resins, epoxy B 7.50

Stiffening agent 3.60

Coupler 0.90

Resins, epoxy gross weight=19.5%

Particle A 64.60

Particle E 16.10

Silver content gross weight=80.5

The volumetric shrinkage pH-value determination pH of above-mentioned polymer support is 7.6%, this carrier is used for connecting as the surface of 68 legs in each circuit of example 1 described 6 test circuits (test circuit 1-6) immobilising device (SMD), 44 legs surface immobilising device and the resistance string that is connected in series.In room temperature and temperature is 60 ℃, in relative humidity is under 90% the test condition, contact resistance to be measured, and its measured value as shown in figure 10.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, through 65,453, after 1096 hours, measures resistivity respectively.Shown in listed " growth percentage " hurdle of Figure 10, be that through 1096 hours, except a set of contact increase in resistance rate surpasses 14%, all other contact resistance ohmic values changed very little under 90% the condition in relative humidity.

Embodiment 10

Employing contains two kinds of conductive particles, and promptly conductive particle A and F conductive particle filler prepare electroconductive binder, and above-mentioned particle A is identical with employed particle A in the example 1.Particle F is the silvered glass spheroid, and this spheroid silver content is about 23.8%, and its Scott volume density is 0.81g/in ³Powder resistivity is milli-ohmcm (willi-ohm cm), and median size is 13 microns, and actual particle size is distributed as 90%＜20.0 micron, 50%＜12.1 micron and 10%＜7.1 micron.Particle F can select for use and be positioned at NJ07072, Carlstadt, and the particle that Potter industrial produces is sold the trade mark altogether and is " Conducto-O-Fil silvered glass ball ".Particle A and F mix as following weight percent, and particle accounts for 92%, and particle F accounts for 8%, thereby form and carrier blended filler mutually.

Carrier mainly comprises and contains two kinds of epoxy resins, i.e. the mixture of Resins, epoxy A and Resins, epoxy B.Resins, epoxy A is a bisphenol F epoxy resin, and as Aratronic 5046, Resins, epoxy B is the liquefied phenol novolac epoxy resin, as Quatrex 2010.

Polymer support can also comprise the coventional type stiffening agent [as the N-(2-cyanoethyl)-the 2-ethyl, 4-methylimidazole] and coupler (as γ-Racemic glycidol propoxy-Trimethoxy silane).

Prepare electroconductive binder by following moiety:

Every batch of consumption-weight percent of moiety (%)

(standard weights unit)

Resins, epoxy A 7.88

Resins, epoxy B 7.88

Stiffening agent 3.78

Coupler 0.96

Resins, epoxy gross weight=20.5%

Particle A 73.14

Particle F 6.36

Silver content gross weight=79.5%

The volumetric shrinkage value of polymer support is 7.6%, and this carrier is used for connecting the 68 legs surface immobilising device (SMD) in each circuit of 6 test circuits (test circuit 1-6) described in the example 1, the 44 legs surface immobilising device and the resistance string that is connected in series.In room temperature and relative humidity is 90%, and temperature is 60 ℃, test condition under, contact resistance is measured, its measured value as shown in figure 11.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, through 65,453, after 1096 hours, measures resistivity.Shown in Figure 11 listed " growth percentage " hurdle, be 90% in relative humidity, after 1096 hours, except two set of contact increase in resistance rates only surpass 15%, other all contact resistance ohmic values change very little.

In some test operations of embodiment 2 to 10 (its result does not provide), high humidity can cause smouldering of hot liquid water, and makes by the lead in the bonding head outside and all corrode, and makes experimental result invalid.

Embodiment 11

The conductive particle filler that employing contains two kinds of silver-colored particle A and B prepares electroconductive binder, the particle A and the B that are adopted in particle A and particle B and the example 2 are identical, and they mix as following weight percent, and particle A accounts for 40%, particle B accounts for 60%, thereby forms and carrier blended filler mutually.

Carrier comprises the mixture of the Resins, epoxy of the synthetic modified rubber of a kind of warp, this mixture comprises bisphenol F epoxy resin, as 5,046 one kinds of Bisphenol F diglycidyl ethers of Aratronic, in the time of 25 ℃, its viscosity is about 1400CPS, and above-mentioned resin can have been bought from Ciba-Geigy company; Liquefied phenol line style phenolic aldehyde epoxy resin, this resin is identical with above-mentioned Bisphenol F epoxy resin content, and this resin can be " Quatrex2010 ", and viscosity is about 25 in the time of 52 ℃, 000-45000CPS, it can have been bought from Dow chemical company; Butadiene acrylonitrile synthetic rubber properties-correcting agent, as Heloxy Wc-8005, its viscosity is about 50 in the time of 25 ℃, 000-1,000,000CPS, it is produced by the Wilming-tom chemical company that is positioned at U.S. Delaware.

Can also comprise the imidazole type stiffening agent in the polymer support, as Curimid-CN, i.e. N-C ₂-cyanoethyl)-2-ethyl-4-methylimidazole; Thinner such as γ-Ding lactones; And coupler, as A-187, i.e. γ-Racemic glycidol propoxy-Trimethoxy silane.

Prepare electroconductive binder by following moiety:

Content of moiety

(weight in wet base)

Bisphenol F 5.05

(line style) phenolic resin varnish 5.05

Divinyl rubber 5.32

Stiffening agent 3.19

Thinner 1.59

Coupler 0.80

Carrier total amount=21.0

Particle A 31.60

Particle B 47.40

Filler total amount=79.0

The volumetric shrinkage value of polymer support is 10%, and bending diameter is 0.50 inch (this value is determined under these circumstances, promptly bend the bar of an about 4.5mil of thickness around the bar of minimum as far as possible diameter, and this bar does not produce cracking or damages).Above-mentioned carrier is used for connecting the 68 legs surface immobilising device (SMD) in each circuit of 3 test circuits (test circuit 1-3) described in the example 1, the 44 legs surface immobilising device and the resistance string that is connected in series.In room temperature with in relative humidity is 90%, and temperature is under 60 ℃ the test condition, contact resistance to be measured, and its measured value as shown in figure 12.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, after 1031 hours, measures resistivity.Shown in 12 listed " growth percentage " hurdles, after through 1031 hours, all contact resistance ohmic values change very little or have also reduced as shown.

Embodiment 13

The conductive particle filler that employing contains two kinds of silver-colored particle A and B prepares electroconductive binder, the particle A and the B that are adopted in particle A and B and the example 2 are identical, and they mix as following weight percent, and particle A accounts for 40%, particle B accounts for 60%, thereby forms and carrier blended filler mutually.

Carrier comprises a kind of packless poly-ammonia rubber, and as Calthane NF 1300, it can have been bought from the Cal Polymer Company that is positioned at California, USA.Above-mentioned rubber serve as reasons a aromatic isocyanate [4, the 4-diphenylmethane diisocyanate and account for the 20%(weight percent) the polymkeric substance with higher molecular weight] and 3 parts of dienite (mixtures that hyroxyl terminated polybutadiene is formed.

Can also comprise a spot of solvent in the polymer support, as carbitol acetic ester [2-(2-ethoxyethoxy)] ethyl acetate, so that regulate viscosity.

Prepare electroconductive binder by following moiety:

Every batch of consumption of moiety

(weight in wet base)

Polyurethane elastomer 15.85

Solvent 1.05

Total weight of carrier=16.90

Particle A 33.24

Particle B 49.86

Filler gross weight=83.10

The volumetric shrinkage value of above-mentioned polymer support is 7.7%, bending diameter is 0.25 inch, and (this value is determined under following situation, promptly the bar bending thickness around minimum as far as possible diameter is the bar of 4.5mil, and this bar does not produce cracking and damages), above-mentioned carrier is used for connecting the 68 legs surface immobilising device in each circuit that two test circuits (test circuit 1-2) described in the example 1 connect, the 44 legs surface immobilising device and the resistance string that is connected in series.In room temperature and relative humidity is 90%, and temperature is under 60 ℃ the test condition, contact resistance to be measured, and its test value as shown in figure 13.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, after 429.5 hours, measures resistivity.Shown in Figure 13 listed " growth percentage " hurdle, after 429.5 hours, all contact resistance ohmic values change very little or a bit reduce.

Embodiment 13

The conductive particle filler that employing contains two kinds of silver-colored particle A and B prepares electroconductive binder, employed particle A is identical with B in particle A and B and the example 2, and they mix as following weight percent, and particle A accounts for 40%, particle B accounts for 60%, thereby forms and carrier blended filler mutually.

Carrier comprises silicone resin, as " SR 900 ", and the conformal coating of a kind of siloxanes, it can have been bought from the silicone products branch of General Electric Company of being positioned at the USA New York.Above-mentioned coating comprises that content is 50% silicone resin solution and toluene solvant, and above-mentioned soltion viscosity is about 500CPS in the time of 25 ℃.

Can also comprise a spot of another kind of solvent in the polymer support, as Aromatic 150, it is a kind of heavy aromatic solvent petroleum naphtha, can buy from the Exxon chemical company that is positioned at Texas, USA.

Prepare electroconductive binder by following moiety:

Every batch of consumption of moiety

(weight in wet base)

Silicone resin " SR 900 " 22.50

Solvent " Aromatic 150 " 4.50

Carrier gross weight=27.00

Particle A 29.20

Particle B 43.80

Filler gross weight=73.00

The volumetric shrinkage value of above-mentioned polymer support is 25.0%, and bending diameter is 0.25 inch (this value is to determine in this case, promptly be about the bar of 4.5mil around the bar bending thickness of minimum as far as possible diameter, and this bar does not produce cracking or damages).Above-mentioned carrier is used for connecting the 68 legs surface fixer (SMD) in each circuit of example 1 described 3 test circuits (test circuit 1-3), the 44 legs surface fixer and the resistance string that is connected in series.In two circuit (test circuit 1-2), the resistance that is connected in series is connected resistance string test equally.In room temperature and relative temperature is 90%, and temperature is under 60 ℃ the test condition, contact resistance to be tested, and its test value as shown in figure 14.Afterwards, be 90% in relative humidity, temperature is under 60 ℃ the test condition, to measure resistivity after 192.5 hours.Shown in Figure 14 listed " growth percentage " hurdle, after 192.5 hours, all contact resistance ohmic values change very little or reduce to some extent.

The invention has the advantages that provides a kind of conductive adhesion agent composition, and it has highly stable electroconductibility and highly stable resistance characteristic under high humidity.Why the present invention has above-mentioned feature, be because a kind of binding agent with a kind of like this volumetric shrinkage scope is provided, when the carrier bulk shrinkage value is positioned at this volumetric shrinkage scope, can guarantee the contact between the particle, and contacting between particle and joint surface, thereby form the joint of dependable performance.

In not breaking away from the appended the spirit and scope of the invention that claim limited in this specification sheets back, and under the situation of their legal equivalent thing, can make various improvement to the above-mentioned electroconductive binder of enumerating of the present invention, but above-mentioned conversion and improvement are conspicuous to those skilled in the art.

Diagram:

The NCR growth rate

INIHAL is initial

The RMIEMP indoor temperature

90%, 60 ℃ of 60 ℃/90%RH relative humidity

Claims

1, a kind of method of making the moisture resistance conductive contact, its step comprises:

Spreading electroconductive binder from the teeth outwards, this electroconductive binder comprises the filler particles that is dispersed in the bonding carrier, this bonding carrier shrinks when solidifying; Provide a certain amount of described carrier can make described tackiness agent bond on the substrate effectively; Make described filler have certain content, and have and help to form the structure that moisture resistance electrically contacts; Described carrier contraction can form and describedly electrically contact.

2, according to the method for the formation moisture resistance of claim 1 conduction contact, its step comprises:

At the described tackiness agent of surperficial spreading, the particulate part of this tackiness agent is from including agglomerate, selecting in the group of surface seepage particle and platy shaped particle, described carrier is solidified, carrier produces and shrinks like this, thereby makes filler particles be in pressured state, does tide with surface formation and electrically contacts.

3, the method that electrically contacts according to the formation moisture resistance of claim 1, its step comprises:

The described tackiness agent of spreading from the teeth outwards, the filler particles of this tackiness agent comprises the conduction platy shaped particle, its thickness is than the length and the little order of magnitude of width, described carrier is solidified, shrink so that described carrier produces, thereby make filler particles be in pressured state, form moisture resistance with the surface and electrically contact.

4, according to the method for the formation moisture resistance of claim 1 conduction contact, its step comprises:

The described tackiness agent of spreading from the teeth outwards, this tackiness agent also comprises Powdered conductive particle, intergranularly electrically contacts to improve, described carrier is solidified, shrink so that described carrier produces, thereby make filler particles be in pressured state, form moisture resistance with the surface and electrically contact.

5, a kind of method that forms the contact of moisture resistance conduction, its step comprises:

The described tackiness agent of spreading from the teeth outwards, the carrier in this tackiness agent comprises one or more Resins, epoxy, and described carrier is solidified, and shrinks so that described carrier produces, thereby makes filler particles be in pressured state, forms moisture resistance with the surface and electrically contacts.