JPH11320684A - Pretreatment method for cleaning base surface before application of dry film resist - Google Patents

Abstract

PROBLEM TO BE SOLVED: To impart adhesive properties to a gap between a dry film photoresist and a base by cleaning the base with an alkaline soap solution for a short time and next plasma-etching the base prior to laminating a dry photoresist film on the surface of the base. SOLUTION: A base is cleaned and a dry photoresist film is laminated on the base. Cleaning the base includes the plasma-etching of the base. An early cleaning step is known widely and for example, includes various pretreatments e.g. cleaning the base with an alkaline soap solution. The plasma-etching can be performed by setting a pressure at 200-500 mm and an electric power at 1,000-about 500 W with the use of O2 , N2 , argon and a small quantity of CF4 . After plasma-etching, the surface of the base is finished, a dry photoresist is applied and the film is laminated under heat and pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to improvements in the use of dry film photoresist in the manufacture of integrated circuit packages and circuit boards.

[0002]

2. Description of the Related Art Photoresists are widely used in the manufacture of integrated circuit packages and circuit boards. For example, to create a via, a photoresist layer is applied to a substrate having a copper layer, the photoresist is exposed and developed, and the unexposed photoresist is removed only where vias are to be formed. Similarly,
One circuit formation process is a plating process that utilizes a photoresist material to mask areas that should not be plated. Both liquid and dry sheet photoresists are known and commonly used by those skilled in the art.

[0003] Liquid photoresists are easy to use and to coat the substrate very uniformly.
Dry photoresist is applied by rolling off the dry film material from a roll, feeding the film onto a substrate, and passing them together between nip rollers to adhere the dry film to the substrate.

[0004] A high adhesion between the dry film photoresist and the substrate is desired so that the areas under the film after exposure and development are not inadvertently plated. Also, good adhesion between the film and the substrate is desirable to prevent unwanted penetration of various materials harmful to the substrate, such as, for example, unwanted penetration of moisture. It is an object of the present invention to provide a pretreatment of a substrate to clean the substrate and to provide adhesion between the dry film photoresist and the substrate.

[0005]

SUMMARY OF THE INVENTION The present invention provides a dry photoresist film, comprising providing the film on a substrate and laminating the film on the substrate. An improved process for laminating a dry photoresist layer involves improving the substrate prior to laminating with a brief cleaning with an alkaline soapy solution and then plasma etching. Will be cleaned by

In the manufacture of printed circuits, it is known to use organic resists that act as selective plating resists or selective etching resists. The desired pattern of the organic resist can be obtained by selectively applying the resist composition to the substrate via appropriate pattern masking, or by photoimaging. In the latter, the photoactive resist composition is applied to the substrate as a layer, and then exposed to a suitable wavelength of activating radiation through a mask. The photoactive composition can be positive-working (negative-working) or negative-working (negative-working), with subsequent development of the composition, depending on the circumstances, the pattern of organic resist corresponding to the negative or positive of exposure Can be left on the substrate.

Prior to the present invention, the substrate was subjected to chemical microetching and / or to remove contaminants therefrom.
Or, it was previously cleaned by mechanical abrasion.
A dry film photoresist is also known, and is a method of applying a dry film photoresist to a substrate.
Generally, a dry film resist is applied to a substrate by a resist roll laminator.

The method comprises the steps of: a) cleaning a substrate;
b) providing a dry photoresist film; c) laminating the dry photoresist film to the substrate, wherein cleaning the substrate further comprises plasma etching the substrate. It is contemplated that any known dry photoresist film will be useful in the present invention. The nature of the substrate on which the film is laminated does not limit the scope of the present invention.

With respect to plasma, the nature of the plasma and the particular etching technique do not appear to be very important. There are several known plasma etching techniques that will be useful and will provide a satisfactory cleaned surface that will bond easily and efficiently to the dry photoresist film. The initial cleaning step is widely known, and various pretreatments such as cleaning the substrate with an alkaline soap solution can be used.

[0010] Plasma etching is performed at O ₂ , N ₂ , argon, and a small amount of CF at a pressure of 200-500 mTorr and a power setting of 1000 Watts to about 5000 Watts.
₄ can be implemented. One skilled in the art can easily determine the appropriate power and settings for the application. After plasma etching, the substrate surface is finished, dry photoresist is applied, and laminated under heat and pressure. This is accomplished by passing the substrate and the applied dry photoresist through a nip roller using a resist roll laminator or any other suitable device.

[0011] Any suitable dielectric material may be used in the present invention, including, but not limited to, polyimide-to-polyimide laminates, epoxy resins, epoxy resins combined with other resin materials. resin,
Any of the above mentioned organic materials alone or in combination with fillers may be mentioned. Preferred dielectric materials include a fluoropolymer matrix, wherein the fluoropolymer is polytetrafluoroethylene (PTFE),
It can be ePTFE or a copolymer, or a blend. Suitable fluoropolymers include, but are not limited to, polytetrafluoroethylene or expanded polytetrafluoroethylene, which may or may not include a mixture of adhesive and filler.

Preferred materials include: L. Gore a
Speech available from nd Associates
dboard® tie layer, for example,
S, a non-woven material prepreg containing a cyanate ester resin in a polytetrafluoroethylene matrix
There is speedboard® C. Speed
board (registered trademark) C has a dielectric constant (Dk) of 2.6 to 2.7 at 1 MHz to 10 GHz, and a dielectric constant (Dk) of 1 MHz to 1 GHz.
At 0 GHz, a dielectric loss tangent of 0.004, 1000 V /
It has a withstand voltage above the mill, a glass transition temperature (T _g ) of 220 ° C., a resin content of 66-68% by weight, and is available in various thicknesses. Speedboard® N, a non-woven prepreg containing a multifunctional epoxy adhesive in an expanded PTFE matrix.
Prepreg can also be used. Speedboard
®N has a dielectric constant (Dk) of 3.0 at 1 MHz, a dielectric tangent of 0.02 at 1 MHz, 90
It has a withstand voltage greater than 0 V / mil, a glass transition point (T _g ) of 140 ° C., a resin content of 66-68% by weight and is available in various thicknesses.

Another suitable derivative is the expanded PTFE matrix of FIG. 1, which comprises at least two of a cyanate ester formulation, an epoxy formulation, a bis-triazine formulation, and a poly (bis-maleimide) resin.
Contains a mixture of seeds. For example, the varnish solution may contain 5.95 pounds of M-30 (Ciba Geigy), 4.07 pounds of RSL1462 (Shell Resins), and 4.57 pounds of 2,4,6-tribromophenyl terminated tetra. Bromobisphenol A carbonate oligomer (BC-5
8) (Great Lakes), 136 g of bisphenol A (Aldrich), 23.4 g of Irganox
1010, MnHEX-CEM in mineral spirits
18.1 g of a 10% solution of and 8.40 kg of MEK
Was prepared by mixing The varnish solution was further diluted into two separate baths of 20% and 53.8% by weight. Pour the two varnish solutions into separate impregnation baths and e
The PTFE web was continuously passed through each impregnation bath from one immediately to the other. The varnish was constantly stirred to ensure uniformity. The impregnated web was then immediately passed through a heating oven to remove all or almost all solvent, partially cure the adhesive, and collect on a roll. ePTFE web is, for example, 25μ
m, can be any desired thickness, such as 40 μm. A 25 μm thick material has a mass of about 0.9 g,
It has a weight of about 11.2 to 13.8 g / m ² per unit area.

Another class of dielectric materials are those in which the porous matrix system contains an adhesive / filler mixture that has been absorbed or impregnated. The porous matrix contains a large amount of filler and a thermosetting or thermoplastic adhesive as a result of the initial void volume of the substrate and is heated to partially cure the adhesive and form a B-stage composite. It is a woven base material. Substrates are disclosed in U.S. Pat. Nos. 3,953,566 and 4,482,516.
No. 4,867,045, including a fluoropolymer such as the porous expanded polytetrafluoroethylene material of each of the above patents, each of which is incorporated herein by reference. Desirably, the average flow pore size (MFPS) should be at least about 2-5 times the maximum particle size, with average flow pore sizes greater than about 2.4 times that of the filler being particularly preferred. It is also within the scope of the present invention that suitable composites can be prepared by selecting the ratio of average flow pore size to average particle size to be greater than 1.4. Also, acceptable composites can be prepared when the ratio of minimum pore size to average particle size is at least greater than 0.8, or when the ratio of minimum pore size to maximum particle size is greater than at least 0.4. The ratio of average flow pore size to particle size is Micro
It can be measured using a trak® type FRA particle analyzer.

Alternatively, another mechanism for measuring relative pore and particle sizes can be calculated assuming that the minimum pore size is at least about 1.4 times the maximum particle size. In addition to the expanded fluoropolymer substrate,
For example, ultra-high molecular weight (U)
Polytetrafluoroethylene prepared by blending HMW) polyethylene, expanded polypropylene, paste extrusion and sacrificial filler, porous inorganic or organic foam, or microporous cellulose acetate can also be used.

[0016] The porous substrate is at least 30%, preferably at least 50%, most preferably at least 70%.
% Initial void volume, which facilitates the impregnation of thermoset or thermoplastic adhesive resin and particulate filler paste in the voids, while at the same time providing flexible reinforcement to prevent overall composite brittleness And stabilize the particles. Filler is Microtrak® model FRA
When analyzed with a particle analyzer of the, contains a set of particles, the maximum particle size, minimum particle size,
And the average particle size.

Suitable fillers to be incorporated into the adhesive include, but are not limited to, BaTiO ₃ , SiO
₂ , Al ₂ O ₃ , ZnO, ZrO ₂ , TiO ₂ , precipitated sol-gel ceramics such as silica, titania, and alumina, non-conductive carbon (carbon black), and mixtures thereof. A particularly preferred filler is S
iO ₂ , ZrO ₂ , TiO ₂ itself, or a combination of these with non-conductive carbon. The most preferred fillers are those made by the steam metal combustion process taught in U.S. Pat. No. 4,705,762 and include, but are not limited to, for example, essentially solid, ie, not hollow spheres, but uniform surface curvature. And silica, titania, and alumina particles obtained from silicon, titanium, and aluminum, which have a high degree of sphericity.

The filler can be treated by well-known techniques to render the filler hydrophobic by using an agent that reacts with the adhesive matrix, such as by a silylating agent and / or by using a coupling agent. Suitable coupling agents include silanes, titanates, zirconates, and aluminates. Suitable silylating agents include, but are not limited to, functional silylating agents, silazanes, silanols, siloxanes. Suitable silazanes include, but are not limited to, hexamethyldisilazane (Huls H730), hexamethylcyclotrisilazane, and silylamides such as bis (trimethylsilyl) acetamide (Huls H730).
B2500), silyl ureas such as trimethylsilyl urea, and silylimidazoles such as trimethylsilylimidazole.

Titanate coupling agents include tetraalkyl type, monoalkoxy type, coordination type, chelate type, and quaternary type.
Illustrated by salt type, neoalkoxy type, cyclohetero atom type. Preferred titanates include tetraalkyl titanates, Tyzor® TOT [tetrakis (2-ethyl-hexyl) titanate], Tyzor
(Registered trademark) TPT [tetraisopropyl titanate], chelated titanate, Tyzor (registered trademark)
GBA [titanium acetylacetylacetonate], Ty
zor (registered trademark) DC [titanium ethyl acetoacetonate], Tyzor (registered trademark) CLA (owned by DuPont), monoalkoxy (Ken-React (registered trademark) KRTTS), Ken-React (registered trademark),
KR55 tetra (2,2-diaryloxymethyl) butyl, di (ditridecyl) phosphite titanate, LICA
® 38 neopentyl (diallyl) oxy, and tri (dioctyl) pyro-phosphate titanate.

Suitable zirconates are any zirconates described in detail on page 22 of the Kenrich catalog, in particular KZ55-tetra (2,2-diaryloxymethyl) butyl, di (ditridecyl) phosphite zirconate, NZ-01-neopentyl (diallyl)
Oxy, trineodecanoyl zirconate, NZ-09
-Neopentyl (diallyl) oxy, tri (dodecyl)
Benzene-sulfonyl zirconate.

The aluminates that can be used in the present invention include, but are not limited to, Kenrich®, diisobutyl (oleyl) acetoacetylaluminate (KA301), diisopropyl (oleyl) acetoacetylaluminate (KA322). ) And KA4
89. Other than the above, for example, crosslinked vinyl polymers such as divinylbenzene and divinylpyridine, or initially very high dilution rates (0.1-0.1 in MEK)
Certain polymers, such as the sizing of any of the disclosed thermoset matrix adhesives applied at 1.0% solution) can be used. Also, certain organic peroxides such as dicumyl peroxide can be reacted with the filler.

The adhesive itself may be thermosetting or thermoplastic, and may be polyglycidyl ether, polycyanurate, polyisocyanate, bis-driadin resin, poly (bis
-Maleimides), norbornene-terminated polyimides, polynorbornenes, acetylene-terminated polyimides, polybutadienes and their functionalized copolymers, cyclic olefins polycyclobutene, polysiloxanes, polycisqualoxane, functionalized polyphenylene ethers, Mention may be made of polyacrylates, novolak polymers and copolymers thereof, fluoropolymers and copolymers thereof, melamine polymers and copolymers thereof, poly (bisphenylcyclobutane), and blends or prepolymers thereof. It should be understood that the above-mentioned adhesives can be blended with each other or with other polymers or additives to provide flame retardancy and enhanced toughness. is there.

In the present application, the average flow pore size and the minimum pore size are defined as the value of Coulte, which directly presents these values.
Measurements were made using an r® Poromerota II (Coulter Electronics, Luton, UK). Average particle size and maximum particle size
The measurements were made using a light scattering particle size analyzer model number FRA (Leads & Northup, North Wales, Pa., USA, Microtrack Division) of the Rak.RTM. type FRA. Average particle size (A
PS) is defined as the value at which 50% of the particles are greater. Maximum particle size (LPS) is
Defined as the largest detectable particle in the k® histogram. Alternatively, the maximum particle size is Micr
One particle analyzer of the otrak (registered trademark) type FRA
It is defined as the minimum point when it is determined that 00% of the particles have passed.

In general, the method of preparing the adhesive and filler dielectric comprises: (a) allowing the lubricated and extruded preform to allow the small particles and the adhesive to flow freely into the void or pore volume; Stretching the polytetrafluoroethylene sheet by stretching to a microstructure sufficient to: (b) make a paste from a polymer and filler of, for example, a thermoset or thermoplastic material, (c) dipping,
Coating, which involves absorbing adhesive and filler paste into a highly porous scaffold such as expanded polytetrafluoroethylene by pressure delivery.

To prepare the filled adhesive film of the present invention, the particulate filler is incorporated into a solvent or aqueous solution or molten adhesive to provide a finely dispersed mixture. The particulate filler usually has a size of less than 40 μm, and preferably has an average particle size of 1 to 10 μm. The average pore size of the polytetrafluoroethylene nodule and fibril structures must be large enough to allow sufficient penetration of the microparticles.

Table 1 shows the average flow pore size (MF) of the substrate.
7 shows the effect of the relationship between PS) and particle size. The ratio of average flow pore size (MFPS) to maximum particle size is 1.
Below 4 results in inferior results. In this case, no uniform composite material is observed, and most of the filler particles do not uniformly penetrate the microporous substrate. The ratio of mean flow pore size (MFPS) to maximum particle size is about 2.
Above 0, a homogeneous composite is obtained. It is also observed that the greater the ratio of average flow pore size to maximum particle size, the higher the relative proportion of the uniform dispersion entering the microporous substrate.

[0027]

[Table 1]

[0028]

EXAMPLE 1 281.6 g of TiO ₂ (TI Pure R-90)
0, DuPont) with the flame retarded dicyanamide / 2-methylimidazole catalyzed bisphenol A in MEK
Based on polyglycidyl ether (Nelco N
-4002-5 (Nelco) in a 20% by weight solution to prepare a fine dispersion. The dispersion was constantly stirred to ensure homogeneity. A small piece of expanded PTFE was then dipped into the resin mixture.
The web was dried at 165 ° C. for 1 minute under tension to obtain a flexible composite. The partially cured adhesive composite obtained in this way has a TiO content of 57% by weight.
₂ , containing 13% by weight PTFE, and 30% by weight epoxy adhesive. Several layers of this adhesive sheet were placed between copper foils and pressed at 600 psi for 90 minutes at a temperature of 225 ° C. by a hydraulic press using vacuum, then cooled under pressure. This resulted in a copper laminate having a dielectric constant of 19.0, which was subjected to a 280 ° C. solder impact for 30 seconds at an average layer thickness of 100 μm (0.0039 inch (3.9 mil)) dielectric laminate thickness. I endured. Example 2 Phenyltrimethoxysilane (04330, Huls /
Petrarch) 386 g SiO
₂ (HW-11-89, Harbison Walke
r) with 200 g of bismaleimide triazine resin (BT206OBJ, Mitsubishi Gas Chemical Company) and 388 g of M
A fine dispersion was prepared by mixing in a manganese catalyst solution of EK. The dispersion was constantly stirred to ensure homogeneity. A 0.0002 inch thick piece of expanded PTFE is then dipped into the resin mixture,
Removed and then dried under tension at 165 ° C. for 1 minute to obtain a flexible composite. Several layers of this prepreg were placed between copper foils and pressed by a hydraulic press using vacuum at a temperature of 225 ° C. at 250 psi for 90 minutes and then cooled under pressure. The resulting dielectric thus obtained contains 53% by weight of SiO ₂ , 5% by weight of PTFE, and 42% by weight of adhesive, has good adhesion to copper, a dielectric constant of 3.3 (10 GHz) and a dielectric loss tangent (10 GHz) of 0.005. Example 3 274.7 g of bismaleimide triazine resin (BT2
060BJ, Mitsubishi Gas Chemical Co.) and 485g of MEK of 483g in manganese catalyst solution SiO ₂ (HW-11
-89) to give a fine dispersion. The dispersion was constantly stirred to ensure homogeneity. Then a 0.0002 inch thick expanded PTF
A piece of E was dipped into this resin mixture, removed, and then 165 ° C. under tension to obtain a flexible composite.
For 1 minute. Several layers of this prepreg were placed between copper foils, pressed at 250 psi for 90 minutes at a temperature of 225 ° C. by a hydraulic press using vacuum, and then cooled under pressure. The resulting dielectric thus obtained comprises 57% by weight of SiO ₂ , 4% by weight of PTF
E, and 39% by weight adhesive, good adhesion to copper, a dielectric constant of 3.2 (10 GHz), and 0.00
A dielectric loss tangent of 5 (10 GHz) was shown. Example 4 15.44 kg of TiO ₂ powder (TI Pure R-
900, DuPont) into a manganese catalyst solution of 3.30 kg of bismaleimide triazine resin (BT206OBH, Mitsubishi Gas Chemical) and 15.38 kg of MEK to prepare a fine dispersion. The dispersion was constantly agitated to ensure homogeneity.
Except that expanded PTFE (TiO ₂ filling rate of thickness 0.0004 inches filled with TiO ₂ was not compressed at the end of a the membrane is 40%, the U.S. Patent of Moruchima 49
(Filled according to the teachings of No. 85296)
It was then dipped into the resin mixture, removed, and then dried under tension at 165 ° C. for 1 minute to obtain a flexible composite. The partially cured adhesive composite thus produced comprised contained 70 wt% of TiO _2, 9% by weight of PTFE, and 21 wt% of the adhesive. Several layers of this prepreg were placed between copper foils and pressed in a hydraulic press using vacuum at a temperature of 220 ° C. at 500 psi for 90 minutes and then cooled under pressure. The resulting dielectric has good adhesion to copper, a dielectric constant of 10.0,
And a dielectric tangent of 0.008. Example 5 7.35kg of SiO ₂ (ADMATECHS SO-
E2, Tsutsumori LTD) with 7.35kg MEK and 7
3.5 g of coupling agent, namely 3-glycidyloxypropyltrimethoxysilane (Dynasylan G
A fine dispersion was prepared by mixing LYMO (Petrach Systems). SO-E2
Has a particle diameter of 0.4-0.6 μm according to the manufacturer,
Specific surface area of 4 to 8 m ² / g, 0.2 to 0.4 g / cc
It is described as a highly spherical silica having a (loose) bulk density.

In this dispersion, methyl ethyl ketone (ME
Primerset PT- of cyanated phenolic resin in K)
30 (Lonza), 932 g of a 50% by weight solution, MEK
RSL1462 (Shell Resins (CAS # 25)
896-38-6)), 896 g of a 50% by weight solution of
380 g of a 50% by weight solution of BC-58 (Great Lakes) in EK, 54 g of a 50% solution of bisphenol A (Aldrich) in MEK, 12.6 g of Irganox 1010 (Ciba Geigy), manganese- 2-
Ethyl hexanoate (Mn HEX-CEM (OMG
3.1 g of a 0.6% solution of the above) and 2.40 kg of MEK were added. The dispersion was subjected to ultrasonic agitation with a Misonics continuous flow cell at a rate of about 1-3 gal / min for about 20 minutes. The fine dispersion thus obtained was subjected to a total bath concentration of 11.9% by weight of solids.
(overall bath concentration).

This fine dispersion was poured into an impregnation bath. An expanded polytetrafluoroethylene web having the knot and fibril structure of FIG. 2 and the following properties was used.

[0031]

[Table 2]

The Frazier number is related to the air permeability of the material being evaluated. Air permeability is measured by tightening the web to a gasket fixture provided in a circular area of about 6 square inches for air flow measurement. The upstream side was connected to a flow meter in series with a supply of dry compressed air. The downstream side of the sample fixture was open to the atmosphere. The test is performed by applying a pressure of 0.5 inch of water to the upstream side of the sample and recording the flow of air through a series flow meter (ball-floating rotor meter connected to the flow meter).

Ball rupture strength is a test that evaluates the relative strength of a sample by measuring the maximum value of rupture. The web is attacked with a 1 inch diameter ball, clamped between two plates. Cha
A tillon force gauge ball burst test was used. The media is placed taut on the measuring device and pressure is applied by lifting the web to contact the ball of the rupture probe. The pressure at break is recorded.

The above-mentioned web is to ensure uniformity,
It was passed through a constantly stirred impregnation bath at a rate of 3 feet / minute or about 3 feet / minute. The impregnated web is immediately passed through a heating oven to remove all or most of the solvent and collected on a roll. Several layers of this prepreg are placed between copper foils and 220 ° C. in a hydraulic press using vacuum.
Press at 200 psi for 90 minutes at a temperature of
It was then cooled under pressure. The resulting dielectric exhibited good adhesion to copper, a dielectric constant of 3.0 (10 GHz), and a dielectric loss tangent (10 GHz) of 0.0085.

The physical properties of the particulate fillers used in Examples 2 and 5 are compared below.

[0036]

[Table 3]

EXAMPLE 6 An expanded polytetrafluoroethylene (ePTFE) matrix containing an impregnated mixture of SiO ₂ -based filler and adhesive prepared by steam combustion of molten silicon was prepared as follows. First, two precursor mixtures were prepared. One was in the form of a slurry containing silanized silica similar to Example 5, and the other was an uncatalyzed blend of resin and other components. -Mixture I-The silica slurry was a 50/50 blend of the SO-E2 silica of Example 5 in MEK, the silica containing a coating of silane equal to 1% by weight of the silica. To a 5 gallon container was added 17.5 pounds of MEK and 79 g of silane, and the two components were mixed to ensure uniform distribution of the silane in the MEK. Then one of the silicas of Example 5
7.5 pounds were added. Add two 5 gallon containers of the MEK / silica / silane mixture to the reactor and add the contents,
That is, the slurry was recirculated by an ultrasonic disperser for about one hour to destroy any silica agglomerates that may be present. The ultrasonic agitation was terminated and the reactor contents were heated to about 80 ° C. for about 1 hour while continuously mixing the contents. The reacted mixture was then transferred to a 10 gallon container. -Mixture II- The product of the desired resin formulation is a MEK-based mixture (adhesive) comprising an uncatalyzed resin formulation containing about 60% solids, Is precisely 41.2% PT-30 cyanated phenolic resin, 39.5% RSL1462 epoxy resin, 16.
7% BC58 flame retardant, 1.5% Irganox 10
A mixture of 10 stabilizers and 1% bisphenol A cocatalyst, all percentages are by weight.

In a 10 gallon container, add 14.8 pounds of PT-30 and 15-20 pounds of MEK and add
-30 was stirred vigorously to completely solvate. Six pounds of BC58 was then weighed and added to the MEK / PT-30 solution and stirred vigorously to solvate BC58. 244.5 g of Irganox 101 as stabilizer
0 and 163 g of bisphenol A were added. 10
Reweigh the gallon container and weigh 14.22 pounds RSL
1462 was added. Additional MEK was added to bring the mixture to a weight of 60 pounds. The contents were then vigorously stirred for about 1-2 hours or as long as necessary to completely dissolve the solid components.

The desired product is a mixture of silane treated silica, an uncatalyzed resin formulation, and MEK, of which 68% by weight of solids is silica;
Total solids is 5-50% by weight of the mixture. The exact solids concentration will vary from experiment to experiment, and will depend in part on the membrane being impregnated. Catalyst levels were PT-30 and RSL1462.
Is 10 ppm with respect to the sum of

The solids content of Mixtures I and II were measured to verify the accuracy of the precursor and to compensate for any solvent splatter that occurred. Mixture I is then added to a 10 gallon container and has 12 pounds of solids, for example, 23.48.
51.5% solids in pounds of Mixture I was obtained. Mixture II was then added to the vessel and 5.64 pounds of solids, for example, 59.46 pounds of 9.46 pounds of mixture II.
6% solids were obtained. 3.45 g of manganese catalyst solution (0.6% in mineral spirits) was added to the mixture of Mixture I and Mixture II and mixed well to make a high solids mixture.

By adding sufficient MEK to the high solids mixture to a total weight of 63 pounds, the ePT
A bath mixture of a 28% solids mixture was prepared for impregnating the FE matrix. Next, an ePTFE matrix was impregnated with the bath mixture to create a dielectric material. Example 7 26.8 g Furneff Black (S obtained from Degussa, Ridgefield Park, NJ)
special Schwarz 100), and 79 g
Coupling agent (Dynaslan GLYMO C)
AS # 2530-83-8, 3-glycidyloxypropyl-trimethoxysilane (Petrach Syst)
ems)) to prepare a fine dispersion. This dispersion is subjected to ultrasonic stirring for 1 minute,
Then 17.5 pounds of ME previously ultrasonically stirred.
It was added to the dispersion during stirring 17.5 pounds SiO ₂ (SO-E2) in K. The final dispersion was heated to reflux for one minute with constant top mixing, and then allowed to cool to room temperature.

Separately, Primaset P in MEK
3413 g of a 57.5% by weight mixture of T-30, MEK
Of a 76.8% by weight mixture of RSL1462 in
g, 5 of BC58 (Great Lakes) in MEK
1495 g of a 3.2 wt% solution, 20 of a 23.9 wt% solution of bisphenol A (Aldrich) in MEK
0 g, 71.5 g of Irganox 1010, 3.21 g of a 0.6 wt% solution of Mn HEX-CEM (OMG) in mineral spirits, and 2.40 kg of M
An adhesive varnish was prepared by adding EK.

In a separate container, 3739 of the above dispersion
g and 0.0233 g of furnace black (Special Schwarz 10 from Degussa, Ridgefield Park, NJ)
0), 1328 g of the above adhesive varnish, and 38.3
Pounds of MEK were added. Pour the mixture into the impregnation bath and e at a rate of 3 feet / minute or about 3 feet / minute.
The PTFE web was passed through the impregnation bath. The dispersion was constantly stirred to ensure homogeneity. The impregnated web was immediately passed through a heating oven to remove all or most of the solvent and collected on rolls.

Several layers of this prepreg are placed between copper foils and pressed at 200 ° C. by a hydraulic press using vacuum.
Pressed at 200 psi for minutes and cooled under pressure. The resulting dielectric exhibited good adhesion to copper. Example 8 Primaset PT-30 in MEK (PMN P-88
3413 g of a 57.5% by weight solution of
2456 of a 76.8% by weight solution of RSL1462 in K
g, 5 of BC-58 (Great Lakes) in MEK
1495 g of a 3.2 wt% solution, 20 of a 23.9 wt% solution of bisphenol A (Aldrich) in MEK
0 g, 71.5 g Irganox 1010, 3.21 g of a 0.6 wt% solution of Mn HEX-CEM (OMG) in mineral spirits, and 2.40 kg M
An adhesive varnish was prepared by adding EK.

In a separate container, place one of the above adhesive varnishes
328 g of 42.3 pounds of MEK, 6.40 g of furnace black (Special available from Degussa, Ridgefield Park, NJ)
Schwarz 100), and 1860.9 g of Si
O was added along with ₂ (SO-E2). The mixture was poured into the impregnation bath and the ePTFE web was passed through the impregnation bath at a rate of 3 feet / minute or about 3 feet / minute. The dispersion was constantly stirred to ensure homogeneity. The impregnated web was immediately passed through a heating oven to remove all or most of the solvent and collected on rolls.

Several layers of this prepreg are placed between copper foils and pressed at 220 ° C. by a hydraulic press utilizing vacuum.
Pressed at 200 psi for minutes and cooled under pressure. The resulting dielectric exhibited good adhesion to copper. It will be apparent to those skilled in the art that various modifications and substitutions can be made to the present invention described above without departing from the spirit and scope of the present invention. Accordingly, it is understood that the present invention has been described by way of example and not limitation.

[Brief description of the drawings]

FIG. 1 is a scanning electron micrograph of an expanded polytetrafluoroethylene (ePTFE) material used for preparing a dielectric material used in the present invention.

FIG. 2 is a scanning electron micrograph of an expanded polytetrafluoroethylene (ePTFE) material used for preparing a dielectric material used in the present invention.

Continuation of the front page (72) Inventor Donald G. Hutchins United States, Wisconsin 54701, Oakrail, Oriole Drive 8336 (72) Inventor Michael Dee. Freeburg, United States, Wisconsin 54730, Colfax, Eight Hundred And Dentence Avenue E 9891

Claims (6)

[Claims] 1. a) providing a dry photoresist film; b) disposing the dry film on a substrate;
Laminating a dry photoresist film on a substrate, comprising, before laminating, cleaning the surface of the substrate to be laminated and then plasma etching the surface. 2. The method according to claim 1, wherein the lamination is performed under pressure and heat. 3. The method of claim 1, wherein the lamination is performed by feeding the substrate and the dry resist film into a nip roller assembly. 4. The method of claim 1, wherein the dry film resist is applied to the substrate by a resist roll laminator. 5. The method of claim 1, wherein the cleaning is a pre-clean to remove contaminants from the substrate. 6. The method according to claim 1, wherein the preliminary cleaning is a washing using an alkaline soap solution.