Norbornene-maleic anhydride

Polymers for use in 193 nm lithography are co-, ter-, and tetra-polymers of 1) methacrylates, 2) norbornenes, 3) norbornene-maleic anhydride, 4) nor-bornene-sulfur dioxide, and 5) vinyl ether-maleic anhydride (Fig. 39). While 1), 3), 4), and 5) are prepared by radical polymerization, all-norbornene polymers 2) are synthesized by transition-metal-mediated addition polymerization [166-168].Norbornenes (Fig.40) are sluggish to undergo radical [168,169] and cationic [170] polymerizations. Their ring-opening metathesis polymerization (ROMP, Fig. 40) [ 171 ] has never produced worthy resist polymers. The C=C double bonds introduced in the ROMP polymer backbone must be hydrogenated to reduce the 193 nm absorption and the ROMP polymers tend to have low Tg. However, the major problem for the ROMP polymers was their unacceptable swelling in aqueous base development. While polymethacrylate systems contain etch-resistant alicyclic structures in the ester side chain, norbornene-based systems carry the alicyclic unit in the backbone. Essentially all the 193 nm re-... 

Models Involving the Participation of Complexes As mentioned in Section 3.1, several copolymerizations that lead to alternating copolymers have been analyzed by the use of the concept of chain transfer complexes. Some of these systems are styrene-maleic anhydride [101-103], allyl acetate-maleic anhydride [104], and norbornene-maleic anhydride [105]. 

One of the typical fluoro polymers is shown in Figure 2.18. A hexafluo-ropropyl alcohol (HFPLA) group is substituted to poly(norbornene maleic anhydride) in the fluoro polymer. Since HFPLA has the same acidity as phenol, the fluoro polymer shows good solubility and transparency. 

The cyclohexadiene derivative 130 was obtained by the co-cyclization of DMAD with strained alkenes such as norbornene catalyzed by 75[63], However, the linear 2 1 adduct 131 of an alkene and DMAD was obtained selectively using bis(maleic anhydride)(norbornene)palladium (124)[64] as a cat-alyst[65], A similar reaction of allyl alcohol with DMAD is catalyzed by the catalyst 123 to give the linear adducts 132 and 133[66], Reaction of a vinyl ether with DMAD gives the cyclopentene derivatives 134 and 135 as 2 I adducts, and a cyclooctadiene derivative, although the selectivity is not high[67]. 

The study of high pressure cycloaddition reactions of tropone (125) with maleic anhydride and norbornene allowed the reaction activation volumes to be measured and showed that they are large, negative and solvent-dependent (Scheme 5.17) [43a]. 

The Diels-Alder reaction is stereo specific. The stereochemistry of the dienophile is retained in the product i.e., cis and trans dienophiles produce different diastereoisomers in the product. For example, freshly distilled cyclopentadiene, having s-cis configuration, reacts with maleic anhydride to give c/ -norbornene-Sjh-endo-dicarboxylic anhydride. 

Cycloalkenones.3 Cycloalkenones can be prepared by a retro Diels-Alder reaction of norbornenes of type 1, conducted at 25-70° in the presence of CH3A1C12 (1 equiv.) and a reactive dienophile, usually maleic anhydride or fumaronitrile. The [4 + 2]cycloreversion was used to prepare 12-oxophytodienoic acid (4), which epi-merizes at Cu to the trans-isomer on brief exposure to acid. The precursor nor-bornene 3 was prepared from the known dienone 2 as shown. Treatment of 3 at room... 

I, maleic anhydride II, 4-phenyl-[1,2,4]triazole-3,5-dione ill, norbornene iv, 2,3-dihydrofuran (xs) ... 

Dimethyl maleate, dimethyl fumarate, (Z)- and (Z)-dibenzoylethylene, maleic anhydride, methyl cinnamate, styrene, methylstyrene, norbornenes and norbornadiene, cyclopentene, tetramethyl- and tetracyanoethylene, and dimethyl tricyclo [4.2.2.0 ]deca-3,7,9-triene-7,8-dicarboxylate react similarly with 2,5-diaryl-l,3-dithiolium-4-olates. In many cases the stereochemistry of the products has been elucidated. 

Some thermosets are made with maleic anhydride only, or with other unsaturated 1,2-dicarboxylic acids or anhydrides such as itaconic acid or methylenesuccinic acid [7], chlorendic acid or 1,4.5,6,7,7-hexachloro-5-norbornene-2,3-dicarboxylic acid (or anhydride), 1,4.5,6,7-pentachloro-5-norbornene-2,3-dicarboxylic acid anhydride or 1,4.5,6-tetrachloro-5-norbornene-2,3-dicarboxylic acid anhydride. These norbomene derivatives can be obtained from the Diels-Alder condensation of the chlorinated cyclopenta-1,3-dienes and maleic anhydride, as shown in the following reaction ... 

Various monomers which fail to undergo polymerization under these conditions are designated "unreactive . However, effective polymerization of these monomers, e.g. maleic anhydride (MAH) and norbornene derivatives, is initiated in bulk or in concentrated solutions, at temperatures where a radical precursor has a short half life, i.e. less than 60 min. It is apparent that these polymerizations require more than the availability of free radicals and that other factors prevail under these conditions. 

The homopolymerization of the endo and exo adducts was carried out in the melt at 150 to 260 C and in chlorobenzene at 120°C (Table I). Polymer was obtained when the catalyst was used at a temperature where the half-life was short, e.g. less than 2 hr, conditions shown to be effective in the homopolymerization of maleic anhydride (16), norbornene (17, 18) and 5-norbornene-2,3-di-carboxylic anhydride (CPD-MAH adduct) (12-15), as well as the... 

It has previously been proposed that the saturated products from the homopolymerization of norbornene (17) and the CPD-MAH Diels-Alder adduct (12-15), and probably from the furan-maleic anhydride Diels-Alder adduct (11), have rearranged structures. An analogous structure would arise from the homopolymerization of the cyclopentadiene-N-phenylmaleimide CPD-NPMI adduct, as follows ... 

As was the case with the polymethacrylate-based resists, the CycloOlefin-Maleic Anhydride (COMA) system attracted a great deal of attention primarily due to ease of polymer synthesis (radical copolymerization) and good lithographic performance. Various norbornene derivatives including tetracyclo-... 

The kinetics of the copolymerization of norbornenes and maleic anhydride has been analyzed in situ by IR spectroscopy [254]. Gas phase FT-IR has been combined with TGA to investigate outgassing from the ketal-based KRS-XE e-beam resist [222]. A flow cell which allows exposure and heating of a resist-coated wafer was attached to the IR spectrometer to study exposure- and temperature-dependent outgassing. Real time deprotection of the KRS resist has been also monitored by infrared reflectance-absorbance spectroscopy [222,494]. 

The reaction of nitrone 101 with cyclic olefins, such as maleic anhydride.61 W-phenylmaleimide,77 cyclopentene,77 norbornene,77 in-dene.77 and acenaphthylene,77 is normal and gives isoxazolidine of type V. Some reactions of a-(6-uracilyl) jV-phenylnitrone are also reported those with allyl alcohol, methyl acrylate, acrylamide, and styrenes, all give 5 substituted 3-uracilylisoxazolidines (type I).79,80 With methyl methacrylate a type III cycloadduct was formed.79,80... 

The reactions with various cyclic olefins are also described. The products have structures similar to those from other nitrones. With maleic anhydride,47 tV-phenylmaleimide,47 norbornene,7,39 nor-bornadiene,39 indene,48 dimethyl bicyclo[2.2.1]hept-2-ene-5,6-... 

Scheme 7.36 Synthetic scheme for the polymerization of norbornene and its derivatives via free radical polymerization (FRP), ring-opening metathesis polymerization (ROMP), and vinyl addition polymerization (VAP) techniques. Polymers I, II, and III are isomers that differ in their enchainment and physical properties. Co- and terpolymerization of norbornene and derivatives of norbornene with other alicyclic monomers such as maleic anhydride, methyltetracyclododecene carboxylic acid, etc. are also successfully synthesized with this scheme. (Note that 2, 3- and 2,7-enchainments of repeating units are reported in type I polymers. °°)...

Houlihan, T. Wallow, A. Timko, E. Neria, R. Hutton, R. Cirelli, J.M. Kometani, O. Nalamasu, and E. Reichmanis, A commercially viable 193 nm single layer resist platform, J. Photopolym. Set Technol. 10, 511 (1997) G. Dabbagh, F.M. Houlihan, I. Rushkin, R.S. Hutton, O. Nalamasu, E. Reichmanis, A.H. Gabor, and A.N. Medina, Model study by FT IR of the inter action of select cholate dissolution inhibitors with poly(norbornene alt maleic anhydride) and its derivatives, Proc. SPIE 3678, 86 (1999). 

Infrared spectroscopy provides a convenient method for studying the deprotection kinetics of resist polymers. For example, the deprotection kinetics of some alicyclic polymer resist systems comprising (i) poly(methylpropyl bicyclo[2.2.1]-hept-5-ene-2-carboxylate-co-bicyclo[2.2.1]hept-5-ene-2-carboxylic acid) (trivial name poly(carbo-t-butoxynorbomene-co-norbornene carboxylic acid) [poly(CBN-co-NBCA)] (I) and (ii) poly(methylpropyl bicyclo[2.2.1]hept-5-ene-2-carboxylate-co-maleic anhydride) (trivial name poly(carbo-t-butoxynorbomene-co-maleic anhydride) [poly(CBN-aZr-MAH)] (11) and containing triphenylsulfonium... 

Thermolysis of the 3,4-dihydro-2//-thiopyran (82) in the presence of dienophiles such as maleic anhydride, styrene, and norbornene gave adducts such as (84) and (85). The thiochalcone (83) is assumed to be an intermediate. The ylide (87), prepared from methyl 6-vinylthian-2-carboxylate (86) and methyl fluorosulphonate, undergoes a 2,3-sigmatropic ring-expansion to methyl l-(methylthio)cyclohept-3-enecarboxylate (88) the cyclopentane (89) is formed as a by-product. ... 

Random co- and terpolymers containing norbornene derivatives and maleic anhydride... 

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