CA2070836C - Electronic articles containing a fluorinated poly(arlene ether) dielectric - Google Patents

Abstract

An electronic article such as a multichip module or an integrated circuit chip has a multilayer interconnect with multiple layers of conductive material made of a fluorinated poly(arylene ether) having a repeat unit such as (I).

Description

2 ~'~ 0~.~~S~~o~204 This invernion relates to electronic articles having a fluorinated poly(arylene ether) dielectric.
Polymer films and coatings are often used in the electronic industry as insulating to materials and passivatbn layers, especially in irnegrated arcuit devices such as muftichip modures. Polymers having a bw dielectric aonstarn s are preferred, because components insulated with them can be designed with higher arcuit densities and can operate at higher speeds and with less signal broadening. The effect of s on the performance of multilayer irnegrated circuit articles is discussed in "Microelectronics Packaging Handbook," Tummala et al.
~5 (eds.), pp. 687-692 (van Nostrand Reinhoid); Watari et al., U.S. Pat.
4,744,007 (1988); and Budde et al., U.S. Pat. 4,732,843 (1988).
Polyimide is an insulator of choice for many electronic applications, because of its superior mechanical and thermal properties and its fabricabiGty irno thin films and coatings.
2o However, polyimide has a relatively high e, a imitation acoenhrated by polyimide's tendency to absorb water (up to 3-4 %) in humid environments. Water absorption causes s to rise, compromising performance. One commercially available polyimide has an a of about 3.2 at 0 relative humidity (%RH), Which rises t0 about 3.8 at 80 ~eRH. As noted by Denton et al. in,), ~gl,14(2),119 (1985), polyimide moisture absorption can also adversely affect 25 performance through increased insulator conductivity, bss of adhesion, or corrosion. Further, some polyimides are susceptible to hydrolysis and/or attack by solverns (often manifested by crazing or cracking upon exposure to a soNern).
It has been proposed, in Mercer, U.S. Pat. 4,835,197 (1989), to improve the solvent 3o resistance of polyimide by curing with an acetylene, maleimide, or vinyl tertHnated curing agent.
However, a polyimide so cured would still have the relatively high dielectric oonstarn of polyimides and their tendency to absorb moisture.
One of us has proposed using fluorinated polymers having a binaphthyl moiety as 3s dielectric materials.
Polyquinoxalines, polyquinozabnes, potybenzoxazoles, and copolymers thereof with polyimides have also been proposed as polymers for microelectronic app~cations by Labadie et al., in SAMPE J. vol . 25, pp.18-22 (Nov.IDec. 1989).
Kellman et al., ACS Symp. Ser. 326, Phase Transfer Catalysis, p. 128 (1987) discloses the preparation of polyethers from diphenols and hexatluorobenzene and decatluorotHphenyl.
atlhough no particular utility is discbsed for the polymers so prepared.
Similar disclosures are made in Keliman et al., Polym. Prepr. 22(2), 383 (1981) and Gerbi et al., J.
Polym. Sci. Polym Letters Ed. 23, 551 (1985).

2~'~~8~~

This invention provides electronic articles having a fluorinated poly(arylene ether) dielectric material. This dielectric material has a low dielectric constant which isllttle affected by increases in the ambient hurt>ic~ty, can be made solvent resistant, and exhibits excellent adhesion to itself and other adherends.
This invention provides an electror>ic article having a dielectric material comprising a fkrorinated poly(aryiene ether) comprising a repeal unit ~ the stnraure to wherein -W- is P
-o-~ ~ ~ ~ o-15 ~P HøPJ m -O ~ O- -U-or ~ ~ , wherein each -A is independently -F. -CI. -Br, -CFg, -CH3, -CH2CH=CH2, or -CgHS: P is 20 0.1, or 2; -Z- is a diced bond. -C(CH3)2-. -C(CF3)g-, -0-. -S-. -S02-, -CO-, -P(C6H5)-, -C(CH3)(C8H5), -C(CgH5)2'. '(CF2)1-8'. or Y
-C
25 wherein -Y- is -O- or a direct bond;
and m is 0,1, or 2:
each -X is independently -H, -CI, -Br, -CF3, -CH3, -CH2CH=CH2, or -CgHS; q is 0, 1, or 2; and n is 1 or 2.

dV0 91/09071 PCT/US90/07204 3 2Q~0~26 Preferably, -V~- is AP AP
°~ ~ t ~ °~
m H4-P ~PJ
corresponding to a fluorinated poly(arylene ether) having the repeat unit AP AP Xq -°~ ~ t H4.P H4-P J m t..F49 n wherein -A, p, -Z-, m, -X, q, and n are as previously defined. Further, the group -Z- is preferably t o para-bonded to each ether oxygen in the benzene rings.
In one embodiment, the electronic article is a multichip module comprising a substrate, a plurality of semiconductor chips carried on the substrate, and a multilayer interconnect connecting the semiconductor chips; the muftllayer interconnect comprising plural layers of conductive is material and plural layers of a dielectric material made of a fluorinated poty(arylene ether) as aforesaid.
In another err~~odiment, the electronic article is an integrated circuit chip having thereon a mutGlayer interconnect comprising p~ral layers of cor>ducUve material and plural layers of a 2o dielectric material made of a fluorinated poly(arylene ether) as aforesaid.
In yet another embo~ment, the electronic article is an integrated circuit chip having thereon a protective coating comprising a fluorinated poly(arylene ether) as aforesaid. In still another embodiment, the electronic article is a circuit board in which the substrate is a fluorinated 2s poty(arylene ether).
Fig. 7a depicts a mu~ichip module having a muftilayer interconnect in which the interlayer 3o dielectric is a fluorinated poly(arylene ether) of this invention. Fig. 1b shows in cross-section the muhllayer interconnect.
Fig. 2 shows in cross-section an integrated arcuit chip having thereon a multilayer interconnect in which the interiayer dielectric is a fluorinated poly(arylene ether) of this invention.

WO 91/09071 O ~ ~ ~ ~ ~ PtrT/US90/07204 Frg. 3 shows in cross-section an integrated arcuit chip protected by a coating of a fluorinated poly(arylene ether) of this invention.
Fg. 3a shows in cross-sect'ron a arcu'tt board in which the substrate is made from a fluorinated poly(arylene ether).
Fg. 4 compares the dielectric constants of polymers of this invention and of comparison polymers not according to this invention.
to Fig. 5 shows a substrate carrying a plurality of multilayer devices having as an interlayer dielectric a crossknked fluorinated poly(arylene ether) of this invention.
t5 The fluorinated poly(arylene ethers) of this invention can be made by the condensation polymerization of a diphenol (I) with a fluorinated monomer (II):

H-W-H + F ~ ~ -~- w ~ ~ + z HF
'F4.ct n ~..F4-q n (I) (B) In the equation above, -W-, -X, q, and n have the same meaning as defined earner.
Suitable diphenols (I) inckrde 4,4'-(hexatluoroisopnopyndene)drphenol, 4,4'-isopropybdene-di(2,6-dimethylpheral), 4,4'~(1-phenylethyidene) bisphenol, 4,4'-isopropyWdenediphenol, 9,9'-bis(4-hydroxyphenyl)fluorene,1,5~iihydroxynapthalene, 2,7~ihydroxynaplhalene, resorcinol, and 4,6-dichbroresorcinol, corresponding to fluorinated poly(arylene ether) repeat units in which -W- is:

~3 -O ~ ~ C ~ ~ O , -O ~ ~ C
t'y'F3 CH3 _ CH3 CH3 O ~ / C ~ / O ' -O ~ / C ~ / O ' Ct>H5 CH3 207U~3~
wl wl _ -o / \ ~ ~ o_ .
\ /
/ \
o i ~ ~
w i \ l -o ~ o- _o I ~ o_ I , or -C1 ~ C1 Preferred diphenols (I) inck~de 4,4'-(hexalluoroisopropypdene)c~phenol, 9.9'-bis(4-hydroxyphenyl)-fluorene, and 1,5-dihydroxynaphthalene.
Suitable fluorinated monomers (II) inckide hexafluorobenxene.
decafluorobiphenyl, pentalluorobenzene, octalNiorotoluene,1,4-~bromotetrafluorobenzene, chbropentatiuoro-. benzene. allylpenfatluorobenzene, and 2,2'.3.3',5,5',8,8'-oGafworobiphenyl.oorresponding to IIuoAnated poly(arylene ether) repeat units in which \I
F~
is p F F F F F F3 H
F F F
Br F
\ / ' ~ ~~~ ' ' , F2 Cl ~2~°~2 BI

WO 91/09071 ~ ~ ~ ~ PCT/US90/07204 or H~! ~ ~ I~~ .
~F3 F3 Preferred fluorinated monomers includes hexafluorobenzene and decafluorobiphenyl.
s Contrary to what has been taught in the art, it has been discovered that complete fluorine substitution of the aromatic ring in monomers (II) is not necessary for effective polymerization, monomers such as pentafluorobenzene, odafk~orotoluene,1,4-dibromotetratluorobenzene, and chloropentafluorobenzene being suitable.
to The two monomers are used in substantially stoichiometric amounts if high molecular weight polymer is desired. Aitematively, 'rf bwer molecular weight material is desired, for example to faalitate the preparation of solutions for spin or other solvent coating operations, a slight stoichiometric excess of either monomer can be used to control the molecular weight.
t5 A base such as an alkali metal carbonate, bicarbonate, or hydroxide is added to the polymerization mixture to convert the phenoxy groups to the corresponding phenoxides. Sodium and potassium carbonate are preferred. A polar aprotfc solvent, such as N,N-dimethylacetamide, N,N-dimethyitormamide, or 1-methyl-2-pyrrolidinone is used. The use of such solvents is r advantageous compared to other solvents such as nitrobenzene, which are more toxic and which 2o are not soluble in water, thereby requiring work-up of the polymerization mixture in an organic solvent as opposed to water. The reac8on is carried out at an elevated temperature, although such temperature should not be excessively high. A temperature between about 50 °C and about 125 °C is generally suitable, with a temperature between about 60 and about 90 °C being especially preferred. Reaction times are typically between about 10 and about 72 hours.
The folbwing repeat units are preferred:
F F F F
~3 ~ / ~ ~ / ~ / (A) F F F~F
F F
~3 ~3 ao F F

2~'~0~~6 H3C , CH3 F F F F
~3 I - -~~ / ~ ~ / ~
~3 F 'F F
(D) F F
F F

~3 ~ ~
H

O (G) ~3 (H) 2~7~~36 s I ~ I _.
I
-° \ / c \ / °~ ~ (I) i ci -° \ / ~ \ / °~ ~ ('') cH2c~I=c~I2 ~3 -° t\ / C \ /
cF3 H~~ /

(L) F F F F
~3 ° \ / ~ \ / \ / \ / ("") ~s F F F F
io F F F F
_° ~3 / \ ~3 Q (M') \ / t~t \ / \ / \ /
~3 ~3 F F F F
The polymers can be homopolymers, consisting essentially of a single repeat unit such as one of the aforementioned ones. Or, they can be copolymers comprising a repeat unit of this ~5 invention in comf~ination with another repeat unit o1 this invention or with a different type of repeat unit. Fluorinated poly(arylene ether) copolymers can be made for example by using two different diphenols (I) as comonomers, or two different fluorinated monomers (II) as comonomers. A
preferred copolymer comprises repeat units (A) and (N):

F F F F
O ( \ O ~ ~ ~ / (N) F F F F
Another preferred copolymer comprises the repeat units (A) and (D). Yet another preferred copolymer comprises repeat un'tts (A) and (O) F F F F
(O) F F F F
Still other preferred copolymers comprise repeat unit (A) and either repeat unit (P) or (O) or repeat unit (D) with repeat unit (O):
to F F F F
O I ~ O ~ ~ ~ ~ (P) F F F F
F F F F
) -O ~ ~ F F F F
15 In a copolymer where a repeat unit of this invention is combined with a repeat unit of another type of polymer, it is preferred that at least 60 mole %, more preferably at least 80 mole %, of the repeat units area fluorinated aromatic ether repeat unit according to this invention. A
capolyrrrer can be altematirp, random, or block.
2o Fig.1a shows a multlchip module 1 of this invention. Substrate 2, typically made of silicon, glass, or ceramic, supports high density mulUlayer interconnect 3 in which the dielectric material providing insulation between the various layers is a fluorinated poly(arylene ether). On interconnect 3 are mounted semiconductor chips 4a-d, which are connected to each other by electrical conductors in interconnect 3. Substrate 1 may also contain electrical conductors, for 25 example for power and ground. Lead frames 5 (only one labeled for simplicity) provide connections to external arcuitry.
Fg. tb shows a partial cross-section of muftilayer interconnect 3 supported on substrate 2. layers of electrical connections t0a-c are separated from each other by a fluorinated t WO 91 /0907 t ~ PCT/US90/07204 poiy(arylene ether) dielectric 12. Via 11 provides connectic>ns between the various layers as necessary. Interconnect 3 is connected to an integrated circuit chip (not shown) by bond pad 13.
Via 1 i is shown here in the stacked pillar design, although it is to be understood that other designs conventional in the art, such as the stair-stepped or nested via designs, can be used.

5 Other muitichip module designs in which the fluorinated po~(aryiene ethers}
of this invention can be used as interlayer dielecirics is disclosed in Balde, 'Overview of Muftichip Technology";
Electronic Materials Handbook, vol. 1, Packaging ASM International, p. 297-312 (1989), 1 o The fluorinated poly(arylene ethers} can also be used as interlayer dietectrics in an interconnect associated with a single integrated circuit chip. Fig: 2 shows this embodiment in cross-section. Integrated arcuit chip 15 has on a surface thereof plural layers 16 of poly(arylene ether} dielectric and multiple layers of metal conductors 17.
i s The fluorinated poly(arylene ethers) of this invention can further be used as protective coatings on integrated crcuit chips, for protection against alpha particles.
Semiconductor devices are susceptible to soft errors when alpha particles emittedl from radioactive trace contaminants in the packaging of other nearby materials strike the active surface. Fg. 3 shows schematically an integrated circuit having a protective coating of f~rorinatecl poly(aryiene ether): Integrated circuit 2o chip 25 is mounted on substrate 26 and held in ptaae with the assistance of adhesive 27. A
coating of fluorinated poly(arylene ether) 28 provides an alpha particle protection layer for the active surface of chip 25. Optionally, additional protection is provided by erxapsutant 29, made of for example epoxy or silicone. Conductor 30 provides connections between chip 25 and conductors (not shown) an substrate 26 and thence to external arcuiiry.
The fluorinated poly(aryiene ethers) can also be used as a substrate (dielectric material) in circuit boards (also referred to as printed wiring boards or PWB's). Figure 3a shows in cross-section a circuit board 35 made of a substrate 36 having on a surface thereof a pattern of conductors 37. Substrate 36 is made of a fluorinated poty(arylene~ether) of this invention.
Substrate 36 may be reinforced with woven noncondfuairg fibers, such as glass Both. Although in Figure 3a the cirwit board is shown as single sided, those skilled in the art will appreciate that other constructions, such as double sided or multitayer, can also be made with a f~orinated poly-(arylene ether} substrate.
3s Films or coatings of fluorinated poiy(arylene ethers) can be formed by solution techniques, such as spraying, spin coating, or casting; with spin coatic~g being preferred. Preferred solvents are 2-ethoxyethyl ether, cyclohexanone, N,N-cfimethylfonmamide. N,N-dimethytacetamide, methyl isobutyl ketone, 2-methoxyethyl ether, 5-methyl-2-hexan'~ne, y-butyrotactone, and mixtures thereof. Typically the coating thidkness is between about 3 to about t5 p.
Additives can be used to enhance or impart partiicular target properties, as is conventionally known in the polymer art; including siatciii,zers, flame retardants, pigments, plastidzers, surfactants, and the like. Compatible or non-compatible polymers can be blended in to give a desired property.

2~70~~~
Polymers for electronic applications desirably contain k~r levels (generally less than 20 ppm) of ionic impurities. If a polymer is made by a synthetic route which requires the use of a tran,Sitiort metal reagent or catalyst, the effed'rve removal of transition metal residues may be a ditficuR task. An advantage of the install polymers is that they can be made by a route which does not involve transition metal species, and the potassuum (or sodium) carbonate reagent and potassium (or sodium) fkioride by-product can be easily removed.
The fluorinated poly(arylene ethers) show good high temperature stability. For example, polymer (A) shows by TGA an initial weigh loss in air at 500 °C.
However, they also unexpectedly t o crosslink when heated in air at temperatures above 300 °C, as sftown by the torrnation of large amounts of gelled material. Preferably, the crossliNdng temperature is between about 300 and about 425 °C. It appears That the presence of oxygen is required for the crosstinking reaction to take place, as similar heating cycles in nitrogen do not lead to the formation of gel. This characteristic makes the fluorinated poly(arylene ethers) particularly useful in the hereindescribed 15 electronic appNcations, because they can be really applied from solution, and then be converted into a solvent resistant coating by heating in air.
The fluorinated poly(arylene ethers) can also be crossanked by bistriazene compounds at the formula Rt N-N=N~~I r ~='/N=N-NRs I I
I'~d.r Hd-r wherein -R~ , -R2, -R3, and ~R4 are independently -H, -CgHS, -CgH4Y', or C~-C4 alkyl;
-R5- is -O-, -S02-, .
~3 O / ~ / O ~ O ~ / C ~ / O-v v p CF3 -O ~ / S ~ / O- ~ -O ~ ~ C ~ / O- , ~ ~3 Br Br Br -O ,_~_ _~~ O- -O ~I_ / ~~ . ~/ o_ , I I i F4.r Fd.r F4.r WO 91/09071 t'CT/US90/07204 20'~0~36 -° \ / \ / °- , ~ s ~ ~ , -l \ i i \ /
°\ / °- ' -B is -F, -CI, -Br, -CHg, or -CFg; r is 0,1, 2, 3, or 4; and -Y' is haiogen, -NCB, -CgHS, or Ct-C4 alkyl.
Preferably, each of -R~, -R2, -Rg and -R4 is methyl and r is 0. Also preferably, -R5- is ~3 -o \ / \ / O- or ° \ / C \ / O-,o It is also preferred that the tMStriazene groups be located para- to the -R5-group.
Particularly preferred bistriazene crosslinldng agents are and These bis~rtazene crosslinking agents can be prepared by treating a solution (in a solvent such as tetrahydroturan or methanol) of a c~amine of the formula H2N~/=) r ~=~/NH2 H4-r H4-r wherein -RS-, -B, and r are as defined hereinabove, with hydrochloric acid (added gradually, with stirring). Theri a solution of sodium nitrite is added gradually, with cooNng.
After a reaction perior of at~out 1 hour, the solvent is removed under reduced pressure. The residue is neutralized to pH

6-7 and treated with the dihydrochloride of a diamine such as dimethylamine.

WO 91/09071 ~ ~ ~ ~ ~ ~ ~ pOI'/US90/07204 The bistriazene crosslinking agent is used in an amount effective to cresslink the fluorinated polymer, preferably between about 10 and about 40, more preferably between about 15 and about 30 weight %, based on the combined weights of the polymer and bistriazene s compound. The fluorinated poly(arylene ether) and the bistriaaene compound are intimately mixed, preferably by solution mixing. A film of the mixture is fom~ed, for example by spin coating, and the solvent is removed. Crosslinking is effected by heating to a temperature above the decomposition temperature of the bistriazene compound, typically between 300 and 400 °C, optionally with a stepped or stagewise heating profile, typically for between about 15 and 90 ~ o minutes total time.
It is beNeved that, when heated up to or above a threshokl temperature, the triazene groups decompose to form phenyl radcais. These then insert into aromatic groups in the fluorinated poly(arylene ether) to form aryl-aryl cross~nkages, as illustrated by the folbwing 15 equations: , , Me' ._ Me M6 N ~ ~ 5 ~ ~ ~ a ~~Rs~ ~ + 2 NZ + 2 ~NMe2 PO = rest of polymer chain P ~ s ~ p + 2 HNMez As a matter o1 convenience, in the equations the trlazene groups have been depicted as decomposirp simultaneously to give a d~radical. H is possible, if not pkely, that the decomposition is not enUrely simultaneous, so that monoradicals are also fom~ed, which, however, would react in a similarlaafaort, albeit sequentially. A noteworthy aspect is that the cross~nks are via aryl-aryl bonds. Compared to their aNphatic oounlerpaAs, these are much less vulnerable to thertnooxidaUve or other chemical attack and hence stabler.
3o Another method of crossiitwdng fluorinated poly(arylene ethers) is with a peroxydic compound, such as dicumyl peroxide, cumene hydroperoxide, or benzoyl peroxide.
An intimate mixture of the polymer and the peroxydic comound is heated to a temperature of between about 350 °C and about 425 °C, preferably about 400 °C, under nitrogen. Typically, the peroxydic compound is used in an amount of between about 5 and about 20 % by weight, based on the combined amounts of polymer and peroxy~c compound, with about 10 wt. % being preferred. In some fluorinated poly(arylene ethers), peroxide crosslir>klng may be faci~tated by their possessing reactive side chains, such as the allyl groups in polymer (J), although the presence of such tunctiona~ties is not required for effective peroxide crossrnking.

WO 91/09071 ~ ~ ~ ~ ~ ,~ ~ PCT/US90/07204 Fluorinated poly(arylene ethers) are also useful as adhesives and matrix resins for composite applications. Further, they are also useful as solvent resistant, cross~nked films for a variety of appications, such as wires having a wrapped insulation, espeaally after crossGnking.
The practice of our invention can be further urxierstood by reference to the foibwing examples, which are provided by means of illustration, not imitation.
E~m~ 1 1 o This example describes the preparation of a polymer having repeat unit (A): To a 500 mt_ round bottom tlaisk was added 15.01 g (x.0447 mole) of 4,4'-(hexafluoroisopropyGdene)diphenol ('8F-diphenol~,15.29 g (0.0458 mote) of decalkarobiphenyl, 240 g of dimethylacetamide ('DMAc'~, and 16.85 g (0.125 mole) of potassium carbonate. The mixture was heated with stirring under r>itrogen at about 80 °C for 23 hours. The mixture was filtered hot to remove the unreacted t 5 potassium carbonate and potassium fluoride by-product. About 75 mt_ of DMAc was removed by rotary evaporatbn. The solution was cooled to room temperature and poured into water to precipitate the polymer. The polymer was filtered, washed three times with water, suspended in 200 mL of ethanol for 2 hours, fihered, and dried at 100 °C for 2 hours to yield a white powder. A
solution of 2 grams of polymer in 8 grams of a 50/50 mixture of 2-ethoxy ethyl ether and 2o cycbhexanone was spin coated onto a ceramic substrate and dried 15 minutes at 100 °C, 20 minutes at 180 °C, end 45 minutes at 400 °C. The resul~np polymer film was tough and flexible, insoluble in 2-ethoxy ethyl ether, and had a Tg of 189 °C by DSC (192 °C by TMA).
~Cem~l9 2 This example describes the preparation of a polymer having repeat unit (B): To a 100 mL
round bottom flask was added 2.20 g (0.0118 mole) of hexafluorobenzene, 3.90 g (0.0116 mole) of 6F-diphenol, 4.0 g (0.030 mole) of potassium carbonate, and 50 g of DMAo.
The mixture was heated with stirtfng under nitrogen at about 70 °C for 48 hours. The mixture was then worked up 3o as descrbed in Example 1 b yield a white powder. A film of the polymer obtained was tough and flexible, ir>8oluble in 2-ethoxy ethyl ether, and had a Tg of about 185 °C by DSC.
This example describes the preparaUon of a polymer having repeat unit (C): The reaction of F~cample 1 was repeated except that 12.7 g of 4,4-isopropyliderte bis(2,8-dimethylphenol) (~tetramethyl Bispheral A'~ was used in place of the 6F-phenol and the reaction was heated to 80 °C for 72 hours. 22.3 g of polymer was obtained. A film of the polymer had a moisture absorpUon of 0.15% alter immersion in 50 °C water for 16 hours.
E~RIe 4 This example describes the preparation of the copolymer having repeat units (A) and (N):
The reaction of tacample 1 was repeated except that a mixture of 7.51 g of 6F-diphenol and 2.458 g of resorcirwl was used in place of the 6F-diphenol. 19.8 g of polymer was obtained. A film of the polymer had a moisture absorption of 0.10% after immersion in 50 °C
water for 16 hours.

wo 91/0907t ~ o ~ o ~ c~ ~ PCT/US90/07204 The polymer having the repeat unit (D) was prepared as follows: To a 250 mL
round 5 bottom flask was added 10.15 g (0.029 mole) of 9,9~bis(4-hydroxyphenyl)fluorene, 9.97 g (0.0298 mole) of decafluorobiphenyl,115 g of DMAc, and 10.0 g (0.074 mole) of potassium carbonate.
The mixture was heated with stirring under nitrogen at 75 °C for i 6 hours. The mixture was cooled to room temperature, poured into rapidly stirring water to preapitate the polymer, filtered, washed twice with water, flitered and dried. A white fluffy powder was obtained. Two grams of the 1 o white polymer powder were ckssolved in 8 grams of a 50150 mixture of cydohexanone and 2-ethoxy ethyl ether. About 1.5 mL of the polymer solution was spin coated onto a glass substrate and dried 10 min at 100 °C,15 min at 200 °C, and 30 min at 400 °C. The resulting polymer film was released from the glass substrate by irtwnersion in water to yield a tough, flexible, transparent film. The film had a electric constant of 2.62 at 0 % RH and a dielectric constant of 2.68 at 58 15 RH. The polymer had a Tg of about 258 °C by DSC.
fi This example describes the preparation of the polymer having the repeat unit (E): The 2o procedure of Example 5 was repeated, except that 5.54 g (0.0298 mole) of hexafluorobenzene was used in place of the decatluorobiphenyl and the reaction was allowed to run for 42 hours.
The resulting polymer film had a dielectric constant of 2.65 at 0°~ RH
and of 2.73 at 58 % RH.
F~camr?le Z
This example describes the preparation of the copolymer having repeat units (A) and (D):
To a 250 ml. round bottom flask was added 5.07 g (0.0145 mole) of 9,9-bis(4-hydroxyphenyl)tluorene, 4.87 g (0.0145 mole) of 8F,~diphenol, 9.97 g (0.0298 mole) of decafluorobiphenyl,115 g of DMAc, and 10.0 g (0.074 mole) of potassium carbonate. The mixture 3o was heated with stirring under nitrogen at 75 °C for 16 hours. The mixture was cooled to room temperature, poured into rapidly stirring water to predpitate the polymer, filtered, washed twice in 300 mL of water, li8ered and dried. A white fktfty powder was obtained. Two grams of the white polymer powder were dissolved in 8 grams of a 50/50 mixture of cyclohexanone and 2-ethoxy ethyl ether. About 1.5 mL of the polymer solution was spin coated onto a glass substrate and dried 10 min, at 100 °C,15 min, at 200 °C, and 30 min. at 400 °C. The resulting polymer film was released from the glass substrate by immersion in water to yield a tough, flexible, transparent film.
The film had a dielectric constant Of 2.60 at 0 % RH and 2.68 at 58 % RH.
This Example describes the preparation of a polymer having repeat unit (F). To a 100 mt.
round bottom flask was added 3.50 g (0.0208 mol) of pentafluorobenzene, 7.00 g (0.0208 mot) of 6F-diphenol, 4.2 g of potassium carbonate, and 50 g of DMAc. The mixture was heated to 80 °C
for 24 hours under nitrogen with stirting, then heated to t 20 °C for an additional 36 hours. The mixture was allowed to cool to room temperature and poured into water to precipitate the polymer as a lightly colored powder. The polymer was washed three times with water and dried at room ,s 20'~0~?6 temperature for 18 hours and at 100 °C for 4 hours. One gram of polymer was dissolved in 4 grams d a 1:1:1 mixture of OMAC, 2-ethoxy ethyl ether, and cycbhexanone. The mixture was spin coated on to a glass substrate and erred 15 min at 100 °C, 15 min at 200 °C, and 15 min at 400 °C to yield an amber film. The polymer had a moisture absorption of 0.150. Based on model studies with similar fluorinated benzenes, discussed in rtare detail bebw, and the expected mechanism for the polymerization reaGion, it is believed that in the pentafkrorobenzene two tluorines are cosplaced, with the hydrogen being retained. Polymer (F) had a Tg of 120 °C by osc to This example describes the preparation of a polymer having repeat unit (G).
The procedure in Example 8 was repeated except that 4.99 g (0.0211 mol) of odafluorotoluene was used in place of pentafluorobenzene and 7.38 g (0.0211 mol) of 9,9-bis(4-hydroxyphenyl)tluorene 15 was used instead of the 6F-diphenol. The reaction was run at 80 °C
for 24 hours and then at 120 °C for an additional 24 hours. A white powder was obtained. Again, it is believed that two ring fluorines are displaced, with the trttluoromethyl group remaining intact. The polymer had a Tg of 260 °C by DSC.
20 iQ
This Example describes the preparation of a polymer having repeat unit (H).
The procedure in Example 9 was repeated except that 6.40 g (0.0208 mol) of 1,4-dibromotetralluorobenzene was used in place of ocfafluorotoluene. A white powder was obtained.
25 One gram of the powder was dissolved in 4 grams of DMAc and spin coated on to glass substrate and cured as described in Example 8 to yield an amber flim. The polymer had a dielectric constant of 2.8 and a moisture absorplbn of 0.15%. Hs Tg was 199 °C as measured by DSC.
CiC-MS analysis of the products from the model rescoon between phenol (2 ecMivalents) splaced with the two 3o and 1,4-dibromotetraikiorobenzene showed that two fiuorines were di , brominss beirp retained and a mixture of isomeric products being obtained.
Thus, it is believed that in poiyrrrer (H), the two bromines were also retained.
a This Example describes the preparation of a polymer with repeat unit (i). To a 100 ml.
round bottom flask was added 5.05 g (0.0249 moQ of chbropenlafluorobenzene, 9.10 g (0.0260 mol) of 9,9-bis(4~hydroxyphenyl)tluorene, 65 g of DMAc, and 11.5 g of potassium carbonate. The mixture was heated 10100 °C for 27 hours under nitrogen with sorting.
The mixture was allowed 4o to cool to room temperature and poured into water with stirring to predpitate the polymer. The polymer was washed with three times with water and dried at room temperature for 18 hours and at 100 °C for 5 hours to yield a whHe powder. Two grams of the polymer were dissolved in 8 m~
of a 1:1 mixture of 2-ethoxy ethyl ether and cycbhexanone, spin coated onto a glass substrate and dried as described in Example 8. An amber film was oMained. The polymer had a moisture absorption of 0.1 %.

CC-MS analysis of the product from the model reaction between phenol (2 ec~ivalents) and chbropentafluorobenzene showed that two fluorines were displaced, w'tth the chbrine being retained and a mixture of isomeric products being obtained. Thus, it is bekeved that, in polymer (I), the chlorine was also retained.
X18 ~
This Example describes the preparation of a polymer with repeat unit (J). To a 100 mt_ round bottom flask was added 4.20 g (0.0202 mot) of allyipeMafluorobenzene, 6.85 g (0.0204 t o mot) of 8F-dipherwl, 45 ml of OMAc, and 8.0 g of potassium carbonate. The mixture was heated to t t 0 °C under nitrogen with stirtirp for 72 hours. The mixture was aNowed to cool to room temperature and was poured into water to preapitate the polymer. The polymer was washed with 100 ml_ of debnized water and 100 mL of denatured ethanol and dried in air for 3 days to yield a IigM yelbw powder. Three grams of the powder and 0.15 g of t-butyl peroxybenzoate were dissolved in 8.5 ml of DMAc and spin coated onto a glass substrate and dried 10 min at 110 °C
and 20 min at 200 °C to yiekf an amber film that was insoluble in OMAc.
GC-MS analysis of the product from the reaction between phenol (2 equivalents) and allylpentatluorobenzene showed that two fluorines were displaced, with the allyl group being 2o retained and a mixture of isomeric products being obtained. Thus, it is believed that, in the polymer described above, the aNyl group was also retained.
~R181~
This example describes the preparation of a polymer with repeat unit (K); To a 100 ml round botbm flask was added 1.25 g (0.0042 mot) 2,2',3,3',5,5',8,8'-octalluorobiphenyl ("OFB"), 1.41 g (0.0042 mot) of 8F-dipheral,19 g of OMAc, and 2 g of potassium carbonate. The mixture was treated to 120 °C for 72 hours under Ntroqert with sUrting. The mixture was albwed to cool to room temperature and poured into water b predpifate the polymer. The polymer was collected by fiHratbn, washed with 75 ml of a 50/50 mixture of ethanol and water, and dried over night at room temperature, folbwed by 1 hour at 100 °C b yield a white powder. The polymer had a Tg of 147 °C by DSC.
aC/MS analysis of the product from the reaction between 4-methoxyphenol (2 equivalents) and OFB showed that two fHiorines were displaced, with retention of the two hydrogens, and a mixture of isomeric products beirp obtained. Thus, it is believed that, in the polymer described above, the two hydrogens were also retained.
E~RIB 14 This example describes the preparation of a polymer with repeat unit (L). The procedure of Example 12 was repeated with the exception that 8.22 g (0.0202 mot) of 1,4-dibromotetrafluorobenzene. 7.07 g (0.0202 mot) of 9,9-bis(4-hydroxyphenyl)fluorene,10 g potassium carbonate, and 55 mt- of DMAc were used. The polymer was obtained as a white powder, Tg 291 °C by OSC.

WO 91/09071 2 0 ,~ o g ~ ~ PCT/US90/07204 This example describes the preparation of a polymer with repeat unit (M). To a 250 ml round bottom flask was added 10.2 g (0.0354 moQ of 4,4'-(1-phenylethylidene) bisphenol, 11.6 g (0.0347 moi) of decafluorobiphenyl, 12 g of potassium carbonate, and 135 g of DMAc. The mixture was heated to 80 °C under nitrogen with sorting for 16 hours.
The mixture was albwed to cool to room temperature and poured iMo water to precipitate the polymer. The polymer was filtered. washed wRh water, and dried. Two grams of the polymer were dissohred in 8 g of a mixture of 2-ethoxy ethyl ether and ctn5ohexanone (ratio 8 : 2, resped'rvely) and spin coated onb a glass substrate, and dried 15 min at 100 °C,15 min at 200 °C, and 15 min at 400 °C to yield a flexible, transparent film. The polymer had a Tg of 208 °C by DSC and a dielectric constant of 2.64 at 0 %RH.
Ex~ 16 ~.
This example describes the preparation of a copolymer having repeat units (A) and (O), in a molar ratio of 1:4. To a 100 ml. round bottom Ilask was added 3.75 g (0.021 mot) of 4,6-dichbroresorcinol,1.76g (0.0053 mol) of 6F-diphenol, 8.80 g (0.026 mol) of decafluorobiphenyl, 62 g of OMAC, and 10 g of potassium carbonate. The mixture was heated under nitrogen for 8 2o hours at 110 °C. The rtaxture was poured without oootirp into water to precipitate the polymer.
The polymer was oolteded by flKratbn, washed with water, and dried to yield a light pink powder.
The polymer had a Tg of 149 °C by DSC.
a This example describes the preparation of a polymer (referred to hereinafter as BPA-OFB) from 4,4'-isopropylidsr>ediphsral and decalWofobiphenyl: The reaction of 6cample 1 was repeated except that 10.20 g of 4,4'-iaopropyWdsnedfphenol (°8isphenol A'~ was used in place of the 6F<liphenol. 21.5 g of polymer was obtained from the reaclbn. A 81m o1 the polymer had a 3o bulk moisture absorption of 0.2 % atler irtwr>erabn in 50 °C water for 16 hours.
E~m~ 18 This is a comparative example in which a polymer not according to this irnention, having the repeat uNt O O
_ _ I
O ' / N I / N- (PMDA-ODA) I - II
O O
is prepared and compared against the polymers of this invention.

wo 9vo9oW PCT/US90/07204 To a 100 m~ round bottom flask was added 1.80 (0.009 moles) g of 4,4'-oxydianiline ('ODA"y and 30 m~ of dry 1-methyl-2-pyrroGdinone ('NMP'~. The solution was~cooled in an ice bath arxi 2.006 g (0.0092 moles) of pyromellitic dianhydridie (PMDA) was added with stirting under nitrogen. A viscous, amber solution resulted. The polymer so~rtion was spin coated onto a 4 by 4 inch (ca. 10 by 10 cm) glass substrate and dried for 10 min at 100 °G, 15 min at 200 °C.
and 30 min at 350 °G to yield an amber film. The film showed a bulk moisture absorption of 2.55%
after immersion in 50 °C water for 16 hours.
to This is another comparative example in which another prior art polyirr>ide, referred to herein as Pi7, is prepared and compared against the polymers of this invention.
O F3C'C~~3 O
~ ~ N-(/ (/
. O O
(PIE
To a 100 mL round bottom flask was added 3.35 c~ (0.009 mole) of 4,4'-bis(4-aminophenoxy)biphenyi and 17 g of NMP. After stirring at room temperature under nitrogen for 45 minutes, a solution of 4.00 g (0.009 mole) of 2,2-bis(3,4-dicarboxyphenyl)fiexafluoropropane 2o dianhydride ('6FDA") in 14 g of NMP was added dropwise with stirring over 10 minutes. After stirring an additional 24 hours at room temperature a visa>us sohrtion (2650 cps) resulted. The solution was spin coated on to a 4 by 4 inch (ca. 10 by 10 cm) glass substrate at 2000 rpm and dried 30 min at 100 °C, 20 min at 200 °C, and 30 min at a50 °C to yield an amber film. This polyimide film showed a bu~c moisture absorption of 0.85°~e after immersion in 50 °C water for 16 hours. The properties of PI7 are compared against those of polymers of this invention in Table 1.
below.
Table I compares the dielectric properties of the polymers of this inver~diort against the properties of the comparative polymers. The dielectric carrstants were measured at 25 °C and 10 ~Iz by the method described in U.S. Patent No. 5,108,840 of Mercer. -w, tt can be seen from Table I that floe polymers of .this invention have sigr>ifrcantly bwer dielectric constants (g), bebw 2.80 at 0 %RH ancf as bw as 2.50, compared to s's above 2.80, up to 3.16, for the cor~artson potymerslyurther, the ~'s of my polymers are less sensitive to variations in the ambient hum'ufrtyr. At about 61) %RH, their e's increase only slightly.
as evidenced by a smati sbpe of between about 10 and about 30, while the comparison polymers have a sbpe ~f between about 60 and about 100. In a mH:roeiedronic article, it is very important that the dielectric material have a low e, preferably below 3 in both dry and wet environments.
These differences between my polymers and the comparison polymers are shown graphically ~n Figure 4.

WO 91/09071 ~ ~ ~ a ~ ~ ~ PL''1'/US90107204 TABLE

Dielectric Constant of Polymers -Dielectric Constanta at 25 C and 10 KHz Ex. PO mer ( a[~ O~o RH) ev, (%RH) SIO
a ' 1 A 2.504 2.62 65.3 17.8 2 B 2.50 2.63 72.3 18.0 3 C 2.78 2.89 65.1 16.9 4 A/N mer 2.62 2.68 54.1 11.1 5 D 2.62 2.68 58 10.3 6 E 2.65 2.73 58 13.8 7 AID co mer 2.60 2.66 58 10.3 8 BPA-DFB 2.617 2.787 65.3 26.1 9 PMDA-ODA 3.16 3.76 58.2 103.2 10 PI-7 2.85 3.223 59.4 63.0 . Sbpe ~ ewet - edrv x 10,000 %RH (Wet) This example describes the preparation of a mufGlayer high density interconnect article suitable for use in a multichip module or in combination with a single integrated circuit chip.
A solution of 22.5 g of polymer (A) in 77.5 g of a 50/50 mixture of 2-ethoxy ethyl ether and cycbhexanone was prepared. A polymeric insulating layer was applied to a ceramic substrate in 1 o the tollowirp manner: (1 ) a 5 mL aliquot of the polymer solution was spin coated onto a clean 125 mm diameter ceramic substrate. (2) The coatitp was dried at t00 °C for 15 min and at 200 °C for another 15 rNn. (3) A second 5 mL aliquot was applied and cured as above with an additional cure for 60 min at 400 °C. A conductive material was formed by blanket sputtering 200 A of chromium followed by 5 miaons of copper, and finally another 500 b of chromium. The metal was 15 photo~thographically patterned.
A aeoortd polymeric insulating layer was applied over the patterned metal layer by the three~atep process described above. An aluminum metal layer was blanket sputtered onto the dielectric, photolithographically patterned, and vias were generated in the second dielectric layer 2o so that electrical contact could be made with the first metal layer. The aluminum layer was removed. A second metal layer of chromiumcopper-chromium was applied as described above and electrical contact was made with the first layer by means of the vies. The second metal layer was then also photoAthographically patterned.
All metal layers in the device showed excellent adhesion to the fluoropofymer and there was no observable delamination of metal to polymer or polymer to polymer.

WO 91/09071 2 ~ ~ O ~ ~ ~ PCT/US90/07204 A sample of polymer (A) was aossGnked by curing in air, for the times and at the temperatures indicated in Table II, below, to produce the indicated gel contents (detemnined by Sohxlet extraction with DMAc for 24 hrs):
Table II
Crosslinking of Polymer (A) However, when polymer (A) was cured in nitrogen for t3 min at 300 °C
and then 27 min at 400 °C, no gel was detected.
to This comparative example demonstrates the preference for f~orination in the bisphenol moiety for the preparation of fluorinated poly(arylerte ethers) having enhanced ihertnal stability.
The thermal stability of polymer (A) (derived from 8F-diphenol and having two -CF3 groups) was compared to that of the polymer BPA-OF8 (derived Irom Bispheral-A and consequently having two -CH3's in the oorreaporxiirp position) by thentagravimetrlc analysis (TQA), under isothermal conditions in air. The resuas are provided in Table III.
Table III
CompaAson of Themtal StabiAty After 3 hr at 0 °C 2.5 3.0 ~ 425 °C 5.0 20.0 This example describes the deposition of layers of polymer (D), crosslinked with a bistriazene crosswnWng agent. A solution of polymer (D) (about 23 weight per cent sods) in a solvent system of 1:1:1 bis(2-ethoxy ethyl)ether, DMAc, and 5-methyl-2-hexanone (WJW/W) was prepared. To this was added 16.7 weight % of the bistriazene (1) WO 91/09071 ~ ~ ~ ~ ~ ~ ~ PCT/US90/07204 This sokatbn was then coated oMO a substrate (ceramic or silicon) by spin coating. The coated substrate was heated in a nitrogen purged oven having a conveyor bait which ran the substrate through the oven axordng to a temperature profile of 300 °C for 6.5 min, 400 °C for 13.5 min, and then cooNng to room temperature over 20 min. This procedure produced a clear coating of cross~nked polymer (D) which dd not crack upon subsequent processing (e.g,, during the deposition of addtbnal polymer layers) and did not cause oxidation of metal conductors thereon.
1o It was found that, to improve the adhesion of the crossinked polymer (D) to the substrate, it is desirable 1o use a thin layer (about 1 p thick) comprising acetylene terminated polyin>ide (Thermid IP-615) and ~raminopropyllrimethoxysilane coupling agent, between polymer (D) and the substrate as an adhesion promoting inteAayer. The polyimidelooupling agent layer is deposited onto the substrate and cured at 150 °C for 10 min and then 200 °C for 15 min. The polymer (D) layer is then coated on top and cured as described above.
This example describes the various steps of metallizatbn, patterning, etching, and via 2o formation on a substrate coated with polymer (D) as described in the previous example.
Metal condudor traces were deposited on a cured polymer (D) coatirp by sputtering. The conductor was a chromium-oopper~chromium sarxlwich, with 200 Jl thick layers of chromium ailing as tle-down layers for the copper (5 w thick). This oondudor construdion is preferable 10 the more conver>tional aluminum, which does rat adhere as well to crosslinked polymer (D).
The metal was covered with a ph~oresist, which was then covered with a mask and exposed ~ ulraviolet light. The exposed portions of the photoresist were rertaved by washing with sodium hydroxide sokrbbn, IeaNng poAlons of the metal exposed. The exposed metal was 3o removed by etcftirp with CRE-473 (tradename for a hydrochbric add etchant, available from T~ar>ser~) and ferric chbrlde to remove respectivvely the top chromium layer and the copper layer.
The bolbm chromium layer was etched away with CE 8001~N (tradename for a ceric ammonium nitrate-nitric add etd>aM, available irom Chemlech Industries). Laser ablation can also be used for rertaving the bottom chromium layer, but CE 8001-N is prelerred because n is fasterand less harsh on the polymer.
After etching of the metal, the unexposed photoresist was removed by iboding the entire substrate wafer with ubraNolet light and devebping otl the remaining photoresist w'tth sodium hydroxide. An alternative method is to strip off undevebped photoresist with a~ 7:3:1 (VNN) ao mixture of NMP, debnized water, and methanol.
The patterned metal is overcoated with more crosslinked polymer (D). A metal layer or via mask about 3 p thick is sputtered oMo the polymer coating and photo~thographically patterned as described above, to forth holes in the metal where vias are desired. The entire water 23 ~ ~ ~ ~ ~ '~ ~j PCT/US90/07204 was ablated with a 308 nm laser, with polymer being removed wherever there was a hole in tfie metal until bottom metal was reached. The mask was then removed by etching -(To avoid etching the metal conductors abng with the via mask, the via mask should be made of dfferent, selectively etchable metal, such as aluminum).
Using the above procedures, a substrate wafer cartying a plurality of muftilayer units was prepared. This substrate and the units thereon is shown schematically in Fg. 5 (where kke numerals depict ike elements). Substrate 40 has thereon a plurality of muttilayer units 41 (also shown in magnified ovefiead and crosssedion views). Each unit 41 has layers of metal t o conductors 43a and 43b isolated by a dielectric 42 of crossliNced polymer (0). has 44a and 44b provide inlerfayer connectivity. Each unit 21 can be viewed as a parallel plate capaator. Twenty units 41 were tested by measuring their capadtances. Each had a capaatance which agreed with that predicted by the ecpration t s C ~ DEpA/l where C is the capaatance. D is the dielectric constant of the polymer iMerlayer, eo is the permittivity of tree space, A is the area of the capaator plates, and L is the distance separating the capaator plates. (The distance between the capadtor plates (i.e., the layers of conductors) 20 was determined to be 35 p by scanning electron microscopy.) In this example, the dielectric properUes of polymer (D) crosspMced with a bistriazene in 25 the manner of Example 23 are compared whh those of a benzocyclobutene ("BCB") resin (XU13005.02L available tram Dow Chemical Company), proposed as a dielectric for electronic packaging applications. Capacitors were made from crosspnked polymer (D) and the BCB resin aocordirp to the procedure of Example 24. The capacilances of strips of five capadtors of made from each polymer were measured as a function of yeRH, before and affer aging.
The results are 3o provided in Table IV.

Table IV

Comparison of Aging Effects on Dielectric Constant of BCB XUt3005.02L
and &striazene CrossGnked Polymer (D) f3Cf3 Pol mer D

Aging in Dielectric Dielectric air 200 C hrs foRH Constant % RH Constant 0 0 2.485 0 2.656 21 2.494 30 2.690 42 2.503 - -78 2.522 69 2.734 24 0 2.747 0 2.623 34 2.817 34 2.662 71 2.897 71 2.702 96 0 2.891 0 2.649 33 3.008 33 2.687 76 3.152 76 2.737 336 0 3.198 0 2.614 28 3.401 30 2.635 82 3.603 73 2.673 These results show that the dielectric properties of crossHnked polymer (D) compare favorably to those of the BCB resin. Although the BCB resin has a lower initial c~electric constant, upon exposure to elevated temperatures, as might occur in the course of the normal service life of an electronic article, the BCB resin's dielectric canstanl increases at a fairly sharp rate, with the increase befrp particularly noticeable at high °~RH's. In contrast, the dielectric constant of polymer (D) remains bw, below 2.8 at all aging time-relative humidity combinations.
F~mg(B 26 to In this example, the crosslinWng of a variety of fluorinated poly(arylene ethers) by a variety of bistriazene crosspNdng agen~s is illustrated.
A sample of fluorinated poly(arylene ether) (2 g) was combined in a 30 mL vial with f 5 cycbhexanone (4 g), T-butyrolactone (4 g), bistriazene compound (ca. 0.4 g) and a surfactant (Fluorad FC-431 from 3M, 2 drops). The mixture was stirred until all the solids had dissolved. The solution was albwed to sit until all bubbles formed by agitatbn had dispersed.
A majority of the solution was deposited o0.a ceramic substrate and spin coated at 250 rpm to form a thick coating.
The sample was soff-baked at 100 °C for 15 min, then at 200 °C
for another 15 min. The sample 2o was then baked in a nitrogen-purged zone furnace accorckng to the folbwing cycle: 300 °C for 6.5 min, 400 °C for 13.5 min, and room temperature for 20 min, to yield a sample of approximately 1.5 g.
This cured sample was removed from the ceramic substrate and divided into three equal 25 sections. Each section was cut into small pieces and placed inside a pre-weighed gauze tube.

The gauze tube was sealed and re-weighed. All three sections were placed inside a Soxhlet extraction apparatus and extracted with DMAc for 24 hr. After drying in a vaaram oven at 100 °C
ovemigM, the samples were cooled and weighed again to detemwne the gel oornent. The results provided in Table V show that bistriazene compounds are generally effective crosslinking agents for fluorinated poly(arytene ethers):
Table V
Crosslinfdng of Fluorinated Poly(arylene Ethers) by &striazene Compounds Men R ~~ Me N_N=N-~ s~N=N_IV
Me ~j Me ..(a lane ether)R~ / BistriazenePer cent ~ Gel D ooMrol 0.00 3.3 0.2 D p, p'_ .O ~ / / o_ 64.1 4.76 0.8 D " 9.1 78.8 1.0 D " 13.04 86.4 t 2.7 p " 16.67 93.7 2.2 p 4.76 46.6 2.4 p, p,_ _o~C~o_ CF' D ~ " 9.1 62.5 2.4 p 13.04 68.6 t 1.6 D " 16.87 86.6 2.6 p P. p'_ _o~o._ 9.1 87.1 5.8 p " 16.67 94.9 0.7 p P. p'_ _p ~ 16.67 81.2 / .I / o. 2.1 F, F4 p 16.67 85.7 ~ t 0.5 I I

p m, m'_ -S02- 16.67 52.9 t 2.2 A control 0.00 0.8 0.8 A P. P~- -'o 18.67 65.3 ~ / / O- 2.9 ~x~m~lB ZZ
1 o In this example, fluorinated poly(arylene ether) 0 is cross~nked with a peroxydic compound. Samples of polymer D containing 10% of dicumyl peroxide or cumene hydroperoxide were heated at 300 °C for 6.5 min and then at 400 °C for 13.5 min under n'ttrogen in an infra-red oven to produce crosslinked polymer having gel content of 94.0% and 81.4%, respectively. In comparison, a sample of polymer D similarly heated in the absence of any peroxide had a gel WO 91/09071 ~ n ~ ~ ~ ~ ~ PCT/US90/07204 content of only 3.3%. The crosslinked polymers retained their low moisture absorption and dielectric constant characteristics. The sample crosswnked with diarmyl peroxide had a moisture absorption of 0.2°~ and a dielectric constant of 2.6 at 0% RH.
In additional peroxide crosslinking experiments, polymers (A) and (D) were each crossanked with 10 wt. % benzoyl peroxide to produce crosskrwced polymers having gel content of about 51 and 49 ~°, respectively. Polymer (A) was also crossYnked with 10 wt. % dicumyl peroxide to a gel content of 69%. In comparison, a control sample of polymer (A), similarly heated in the absence of any peroxide, had a gel content of about 0.8 ~°.
to This example describes the preparation of a polymer with the repeat unit (M').
To a 100 mL round bottom flask was added 3.21 g (0.0093 mol) Bisphenol P, 3.12 g (0.00934 mol) decafluorobiphenyl, 4.2 g of potassium carbonate, and 22 g DMAc. The reaction mixture was heated at 100 °C for 6 hours under nitrogen with sliming. The polymer was isolated as described in Example 5 to yield a white powder. The polymer t>ad a Tg of 162 °C
by DSC. A film of the polymer had a dielectric constant of 2.58 at 0% RH and 2.71 at 66.45% RH.
This example describes the preparation of the copolymer having repeat units (A) and (O).
To a 100 mL round bottom flask was added 3.75 g (0.026 mol) of 4,6-dichbroresorcinol,1.76 g (0.0052 mol) of 6F-diphenol,10.45 g (0.031 mol) of decafluorobiphenyl,l2 g potassium carbonate, and 39 g of OMAc. The reactbn mixture was healed to 110 °C
for a hours under nitrogen with stirring. The gelled reaction mixture was albwed to cool to room temperature and added to water and digested in a blender to isolate an oH-white powder. The powder was washed wHh water and dried. The polymer had a Tg of 149 °C by DSC.
~ppp~ ~Q
This example describes the preparation of the copolymer having repeat uMts (A) and (P) To a 100 mL round bottom flask was added 5.70 g (0.017 mol) of decafluorobiphenyl,1.34 g (0.0083 mon of 2,7-dihydroxynaphthalene, 2.82 g (0.0083 moQ o16F-diphenol. The reaction mixture was heated to 90 °C for 18 hours under Ntrogen with sliming and albwed to cool to room temperature The polymer was isolated by the procedure described in Example 5 to yield a white powder. The polymer had a Tg of 190 °C by DSC. A film of the polymer had a dielectric constarn Of 2.54 at 0% RH and 2.84 at 65.4% RH.
~,mRle ~1 This example describes the preparation of the copolymer having repeat units (A) and (C
The procedure described in the Example irtxnedrateiy above was repeated except chat 1.34 g (0.0083 mop of 1,5-dihydroxynaphthalene was used instead of 2,7-s~hydroxynaphthalene. An o.' a5 white powder was obtained. The-polymrer had a Tg of 203 °C by DSC.

WO 91/09071 ~ ~ ~ ~ ~ ~ ~ PCT/US90/07204 This example describes the preparation of a copolymer having repeat units (D) and (Q) and its subsequent crosslinking w'tth a peroxide. To a 250 mL round bottom flask alas added 3.32 g (0.0207 mol) of 1,5-~hydroxynaphthalene, 7.26 g (0.0207 mon of 9,9-bis(4-hydroxyphenyl)fluorene, 14.22 g (0.0427 mol) of decafluorobiphenyl, t7 g of potassium Carbonate, and 127 g of OMAc. The mixture was heated to 85 °C for 16 hr under nitrogen with stirring and then poured while still hot into a blender containing 300 mL of water to precipitate the polymer. The polymer was collected by filtration and washed twice more with 300 mL of water t o and dried. Two grams of polymer and 0.22 g of dicumyl peroxide were dissolved in 8.5 g of a 1:1 mixture of y-butyrolactone and cyclohexanone. The solution was spin coated onto a ceramic substrate and cured as follows: 30 min at 130 °C, heat to 400 °C
at a rate of 5 °C/min, hold at 400 °C for 15 min, and cool to room temperature at a rate of 3 °C/min. An amber film was obtained, which did not stress crack or dissolve when exposed to the aforementioned ~butyrolaclone-cycbhexanone mixture. A control film of the copolymer, similarly heated under nitrogen but without the added of dicumyl peroxide, showed solvent induced stress cracking when exposed to the same solvent mixture.

Claims (14)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. An electronic article having as a dielectric material a fluorinated poly(arylene ether) comprising a repeat unit of the structure wherein -W- is wherein each -A is independently -F, -Cl, -Br, -CF3, -CH3, -CH2CH=CH2, or -C6H5; p is 0,1, or 2: -Z- is a direct bond, -C(CH3)2-, -C(CF3)2-, -O-, -S-, -SO2-, -CO-, -P(C6H5)-, -C(CH3)(C6H5), -C(C6H5)2-, -(CF2)1-6-. or wherein -Y- is -O- or a direct bond;
and m is 0,1, or 2;
each -X is independently -H, -Cl, -Br, -CF3, -CH3, -CH2CH=CH2, or -C6H5; q is 0, 1, or 2; and n is 1 or 2.

2. ~An electronic article according to claim 1, wherein the electronic article is a multichip module comprising a substrate, a plurality of semiconductor chips carried on the substrate, and a multilayer interconnect connecting the semiconductor chips; the multilayer interconnect comprising plural layers of conductive material and plural layers of a dielectric material made of a fluorinated poly(arylene ether) as defined in claim 1.

3. ~An electronic article according to claim 1, wherein the electronic article is an integrated circuit chip and a multilayer interconnect on the chip, the multilayer interconnect comprising plural layers of conductive material and plural layers of a dielectric material, wherein the dielectric material comprises a fluorinated poly(arylene ether) as defined in claim 1.

4. ~An electronic article according to claim 1, wherein the electronic article is an integrated circuit chip having thereon a protective layer, wherein the protective layer comprises a fluorinated poly(arylene ether) as defined in claim 1.

5. ~An electronic article according to claim 1, wherein the electronic article is a circuit board comprising a subtrate having on a surface thereof a conductor pattern, wherein the substrate comprises a fluorinated poly(arylene ether) as defined in claim 1.

6. ~An electronic article according to any of claims 1-5, wherein in the fluorinated poly(arylene ether) -W- is

7. ~An electronic article according to any of claims 1-5, wherein in the fluorinated poly(arylene ether)

8. ~An electronic article according to any of claims 1-5, wherein the dielectric material comprises a fluorinated poly(arylene ether) comprising a repeat unit of the structure

9. An electronic article according to any of claims 1-5, wherein the fluorinated poly(arylene ether) has been crosslinked with a bistriazene compound of the formula wherein -R1, -R2, -R3, and -R4 are independently -H. -C6H5, -C6H4Y', or C1-C4 alkyl;
-R5- is -O-, -SO2-, -B ;s -F, -Cl, -Br, -CH3, or -CF3; r is 0, 1, 2, 3, or 4; and -Y' is halogen, -NO2, -C6H5, or C1-C4 alkyl.

10. An electronic article according to claim 9, wherein the bistriazene compound is

11. An electronic article according to any of claims 1-5, wherein the fluorinated poly(arylene ether) has been crosslinked by heating in air at a temperature between about 300 and about 400 °C.

12. An electronic article according to any of claims 1-5. wherein the fluorinated poly(arylene ether) has been crosslinked by heating an intimate mixture thereof with a peroxydic compound.

13. An electronic article according to claim 12, wherein the peroxydic compound is selected from the group consisting of cumene hydroperoxide, dicumyl peroxide, and benzoyl peroxide.

14. An electronic article according to claim 13, which is a multichip module.