NL1012854C2 - Sulphony oximes for i-line photoresists with a high sensitivity and a large resist thickness. - Google Patents

Description

Sulfony oximes for i-line photoresists with a high sensitivity and a large resist thickness

The present invention relates to compositions comprising latent acid compounds, to the use of these compounds as a photosensitive acid generator, especially in chemically enhanced photoresists, in printing plates, color filters or image recording materials which can be developed in an alkaline medium , its use as solution inhibitors in a corresponding positive photoresist and a method of producing images using such resists, printing plates or image recording materials.

A chemically enhanced photoresist means a resist composition of which the photosensitive component upon irradiation generates only that amount of acid required to catalyze a chemical reaction of at least one acid sensitive component of the resist, as a result of which the first develop the final differences in solubility between irradiated and non-irradiated areas of the photoresist.

Industrial paint formulations based on a wide variety of photosensitive oxime sulfonates and conventional acid-curable resins are described in US 4540598. These formulations are first cured with actinic light, especially with radiation in the range of 250 to 400 nanometers. The oximesulfonates generate acid, so that a thermal curing whereby the material also becomes insoluble in conventional solvents can take place even at quite low temperatures. Nothing can be concluded with respect to image-wise exposure of corresponding resist films or related problems as well as the image properties of the numerous formulations that fall within the generic scope of the teachings of this patent application.

Oxime sulfonates, which are sparingly soluble in alkaline-aqueous developers, can be converted to the soluble form of the free acid by irradiation. Therefore, when combined with a suitable film-forming resin, they can be used as solution inhibitors for the production of positive resists.

Conventional positive photoresist compositions based on oximesulfonates and alkali-soluble binders, usually cresol novolacs or hydroxymethacrylate / acrylic acid copolymers, are also known and are described in EP 0241423. According to this reference, radiation from 200 to 600 nm can be used. 1 2 85 4 2 to expose the resists. However, the shortcoming of these photoresists is that the resolution and sensitivity are never entirely satisfactory at the same time. This is especially the case when exposed to radiation in the range of the mercury-i line, which has a wavelength of 365 nanometers and is often used for the imagewise exposure of resist films, because medium and high pressure mercury lamps are cheap radiation sources are for producing radiation of these wavelengths with good intensity.

Accordingly, there is a clear need for reactive, nonionic, latent acid generators that are thermally and chemically stable and which, after being activated by light, in particular by radiation of the wavelength of the mercury i line (365 nm), can be used as catalysts for various acid-catalyzed reactions, such as polycondensation reactions, acid-catalyzed de-polymerization reactions, acid-catalyzed electrophilic substitution reactions, or the acid-catalyzed deprotection groups. In particular, there is a need for acid generators which can be activated by light and which can illuminate systems of greater thickness in a manner so that at the same time high sensitivity and good shape of the resist profiles are maintained. Such a great thickness is e.g. of advantage for ion implantation processes, where constantly increasing ion doses require thicker layers to resist ion bombardment. There are further areas of application where thick resist layers are required for simple geometric reasons, such as, for example, the production of magnetic heads for the hard drives of storage media. High thermal stability for obtaining high resistance to ion treatment during ion implantation processes commonly used during semiconductor device manufacturing is an additional desirable property.

US 5627011 describes the use of oximesulfonate compounds in high resolution i-line photoresists with high sensitivity. This publication mentions oxime sulfonate compounds that can generate aromatic sulfonic acids. EP 780729 and WO 98/10335 disclose chemically enhanced resist compositions comprising oximesulfonate compounds with alkyl rather than aromatic sulfonic acid groups.

10 1 2854 3

JP 9-292704 discloses that resist properties are further improved when oximesulfonate compounds with lower alkyl sulfonic acid groups (C1-C4) with a molar extinction coefficient ε <100 at the i-line (365 nm) are used

The present invention provides photoresist compositions with excellent resist profiles while at the same time maintaining excellent sensitivity even at a resist layer thickness much larger than the usual range of 1-2 microns. These properties are particularly observed when the resist compositions are exposed to radiation in the mercury i line range, which has a wavelength of about 365 nanometers.

Surprisingly, excellent profiles and at the same time good sensitivity are obtained with chemically enhanced photoresist compositions that can be developed in aqueous-alkaline media and have a resist thickness greater than 2 µm by using photoacid generators having a molar extinction coefficient ε less than 10. This applies to both negative and positive photoresists containing an acid sensitive component that undergoes an acid catalyzed chemical reaction thereby changing the solubility of the compositions in aqueous alkaline developers.

Accordingly, this invention relates to compositions that can be activated by light, comprising (a) at least one compound that can be cross-linked by the action of an acid and / or (b) at least one compound whose solubility changes under the action of an acid and (c) as a photoinitiator at least one compound comprising a structural unit of the formula I / c = no-so2- (|) § which generates an acid under the exposure to light with a wavelength of 240 to 30 390 nm and with a molar extinction coefficient ε less than 10 at the i-line (365 nm).

In particular, compound (c) is a compound that generates a sulfonic acid.

Compositions with a thickness greater than 2 µm when coated on a substrate are preferred.

10 1 2 85 4

Preferred compositions are those which comprise as component (c) a compound of the formula la 4

NC

5 R, \\ c = n-o-soz-r6 - 4 4 where

Rt, R2, R3, R4 and R5 independently of one another are hydrogen or unsubstituted or halogen-substituted C1-C12 alkyl; or R 1, R 2, R 3, R 4 and R 5 are halogen; R 6 is unsubstituted or halogen-substituted C 1 -C 6 alkyl, phenyl-C 1 -C 3 alkyl, camforyl, phenyl, naphthyl, anthracyl, or phenanthryl, the radicals phenyl, naphthyl, anthracyl, and phenanthryl being unsubstituted or substituted with one or more of the radicals halogen, C1-C4 haloalkyl, CN, NO2, C1-C16 alkyl, phenyl, OR10, COOR9, -O (CO) - * C1-C4 alkyl, SO2OR9 and / or with NR7R &; R7 and R8 are independently hydrogen or C1-C12 alkyl, which is unsubstituted or substituted with OH, C1-C4 alkoxy, C1-C12 alkylsulfonyl, phenylsulfonyl, (4-20 methylphenyl) sulfonyl and / or with C1-C6 alkanoyl ; or R7 and R8 are C2 -C12 alkyl interrupted by -O- and unsubstituted or substituted with OH, C1 -C4 alkoxy, C1 -C12 alkylsulfonyl, phenylsulfonyl, (4-methylphenyl) sulfonyl and / or with C1 -Co alkanoyl; or R 7 and R 9 are phenyl, C 2 -C 6 alkanoyl, benzoyl, C 1 -C 6 alkylsulfonyl, phenylsulfonyl, (4-methylphenyl) sulfonyl, naphlylsulfonyl, anthracylsulfonyl or phenanthrylsulfonyl; 25 or R7 and Re, together with the nitrogen atom to which they are attached, form a 5, 6 or 7 membered ring which may be interrupted by -O- or by -NRi 1-; 1012854 5 R-9 is C1-C12 alkyl which is unsubstituted or substituted with OH and / or with C1-C4 alkoxy, or R9 is C2-C12 alkyl interrupted by -O- and which is unsubstituted or substituted with OH and / or with C1-C4 alkoxy;

R 10 is hydrogen or C 1 -C 12 alkyl, which is unsubstituted or substituted with phenyl, 5 OH, C 1 -C 12 alkoxy, C 1 -C 12 alkylsulfonyl, phenylsulfonyl, (4-methylphenyl) sulfonyl and / or with C 2 -C 6 alkanoyl; or R10 is C2-C12 alkyl interrupted by -O- and unsubstituted or substituted with phenyl, OH, C1-C12 alkoxy, C1-C12 alkylsulfonyl, phenylsulfonyl, (4-methylphenyl) sulfonyl and / or with C2- C6 alkanoyl; or Rio is phenyl;

R n is hydrogen, unsubstituted or OH-substituted C1-C12 alkyl or C2-C12 alkyl interrupted by -O-; and wherein the compounds of formula la are characterized by a molar extinction coefficient ε less than 10 at 365 nm.

According to this invention, it is also possible to use mixtures of isomeric forms (cis-trans isomers, E / Z or syn / anti-isomers) of the oxime sulfonates of the formula la.

C1-C18 alkyl is linear or branched and is, for example, C1-C16, C1-C14, C1-C12, Ci-Cg, Ci-C0 or C1-C4 alkyl. Examples are methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, 2,4,4-trimethylpentyl, 2-ethylhexyl, octyl, nonyl, decyl, dodecyl, tetradecyl, pentadecyl, hexadecyl and octadecyl. C 1 -C 16 alkyl, C 1 -C 12 alkyl, and C 1 -C 4 alkyl all have the same meanings as given above for C 1 -C 18 alkyl, up to the appropriate number of C atoms.

Halogen is fluorine, chlorine, bromine and iodine, especially fluorine, chlorine and bromine, preferably fluorine and chlorine.

Halogen-substituted C 1 -C 18 alkyl or halogen-substituted C 1 -C 12 alkyl are alkyl radicals as described above which contain one or more than the same or different halogen atoms as substitents. For example, there are 1 to 3 or 1 or 2 halogen substituents on the alkyl radical. The halogen atoms are either on the same carbon atom, but they can also be on different C atoms of the alkyl radicals. Examples are fluoromethyl, chloromethyl, bromomethyl, trifluoromethyl, 1-chloroethyl, 2-chloroethyl and the like. C1-C4 haloalkyl corresponds to C1-C4alkyl which is substituted with halogen. The same explanations as given above apply to these residues, up to and including the corresponding number of C atoms.

C2 -C12 alkyl, which is interrupted by -O-, is linear or branched and is, for example, 1-6 times, for example, 1-3 times, or interrupted once or twice by -O-. The O atoms in the alkyl chain are placed non-sequentially. This gives structural units such as -CH2-0-CH2-, -CH2CH2-0-CH2CH2-, - [CH2CH20] y-, 5 - [CH2CH20] z-CH2-, where y = 1-6 and z = 1-5 - (CH 2 CH 2 O 2 Cl 2 Cl 2 -, -CH 2 -CH (CH 3) -0-CH 2 -CH (CH 3) - or -CH 2 -CH (CH 3) -0-CH 2 -CH 2 CH 2 -.

C 1 -C 12 alkoxy is a linear or branched moiety and is C 1 -C 6, C 1 -C 6, C 1 -C 4 alkoxy, for example, methoxy, ethoxy, propoxy, isopropoxy, n-butyloxy, sec-butyloxy, iso-butyloxy, tert-butyloxy, pentyloxy, hexyloxy, heptyloxy, 2,4,4-trimethylpentyloxy, 2-10 ethylhexyloxy, octyloxy, nonyloxy, decyloxy or dodecyloxy, especially methoxy, ethoxy, propoxy, isoporpoxy, n-butyloxy, sec-butyloxy, isobutyloxy or tert- butyloxy, preferably methoxy. C1-C4 alkoxy has the same meanings as above, up to and including the corresponding number of C atoms.

C1-C12 alkylsulfonyl means C1-C12 alkyl-O-SC> 2-, wherein the C1-C12 alkyl radicals are defined as described above.

C 1 -C 6 alkanoyl is linear or branched and is, for example, C 1 -C 4 alkanoyl. Examples are formyl, acetyl, propionyl, butanoyl, isobutanoyl, pentanoyl or hexanoyl, preferably acetyl.

Phenyl-C 1 -C 3 alkyl is, for example, benzyl, phenylethyl, α-methylbenzyl or α, α-di-methylbenzyl, especially benzyl.

Substituted phenyl, naphthyl, anthracyl and phenanthryl radicals are substituted one to four times, for example, one, two or three times, especially once or twice. The substituents on the phenyl ring are in the 2 position; 2.4 place; 2.6 place; 3 place; 3.5 place; 4 place; or 6-position, especially in the 2-position, 3-position, 4-25-position or 6-position of the phenyl ring.

When R7 and Rg, together with the nitrogen atom to which they are attached, form a 5, 6 or 7-membered ring which may be interrupted by -O- or by -NRi 1-, saturated or unsaturated rings are formed, such as aziridine, pyrrole, pyrrolidine, oxazole, pyridine, 1,3-diazine, 1,2-diazine, piperidine or morpholine.

The terms "and / or" or "or / and" in the claims and in the description indicate that not only one of the defined alternatives (substituents) may be present, but also several of the defined alternatives (substituents) together , namely mixtures of different alternatives (substituents).

10 12 85 * 7

The term "at least" means one or more than one.

The molar extinction coefficient ε of the acid generating compounds suitable for the compositions of the present invention is less than 10 at 365 nm (mercury i line). The coefficient ε is part of the Lambert-Beer-5 equation, which is known to an expert. This coefficient is determined from the UV absorption spectrum of the compounds, which is measured in conventional organic solvents such as acetonitrile or tetrahydrofuran (THF). Since ε values shift slightly depending on the solvent used to measure the UV spectrum, all values of this invention refer to THF 10 as a solvent.

In general, any compound that generates an acid upon irradiation and with an extinction coefficient molar ε of less than 10 is suitable for the compositions of the present invention and the claimed photoresists, respectively. Suitable are, for example, compounds that generate Lewis acids as well as compounds that generate Brönsted acids, such as, for example, compounds that generate carboxylic acids, sulfonic acids, phosphonic acids, PFO ', BF4', SbFs' and the like. Examples of such compounds are sulfonium and iodonium salts as well as derivatives of nitrobenzyl sulfonates and bis-sulfonyldiazomethanes. Preferably compounds that generate sulfonic acids, such as oximesulfonate compounds, are used in the claimed compositions.

In particular, the oximesulfonate compounds suitable as acid generators in the compositions of the invention are compounds of the formula Ia, having a molar extinction coefficient ε less than 10, wherein R 1, R 2, R 3, R 4 and R 5 are independently hydrogen, C 1 -C 8 alkyl, halogen or C 1 -C 4 haloalkyl; and R 6 is C 1 -C 18 alkyl, phenyl-C 1 -C 3 alkyl, camforyl, C 1 -C 10 haloalkyl, phenyl, naphthyl, anthracyc, or phenanthryl, wherein the phenyl, naphthyl, anthracyl, and phenanthryl radicals are unsubstituted or substituted with one or more of the halogen, C1-C4 haloalkyl, CN, NO2, C1-C16 alkyl, phenyl, OR10 radicals; and R10 is as defined above.

The compositions preferably comprise compounds of the formula Ia, with a molar extinction coefficient ε less than 10, wherein to 1 2834 8

R1, R2, R3, Rt and R5 are independently hydrogen, C1 -C4 alkyl, halogen or C1 -C4 haloalkyl with the proviso that at least two of the radicals R1, R2, R3, R4 or R5 are hydrogen; and R 1 is C 1 -C 12 alkyl, phenyl-C 1 -C 3 alkyl, camforyl, C 1 -C 4 haloalkyl or phenyl, wherein the phenyl moiety is unsubstituted or substituted with one or more halogen, C 1 -C 4 haloalkyl, NO 2, C 1 -C 8 alkyl , phenyl or OR10; and R10 is C1 -C12 alkyl.

Examples of latent sulfonic acids of the formula la are the methanesulfonates, butanesulfonates, benzenesulfonates, 4-methylphenyl sulfonates, 4-methoxybenzenesulfonates, and 10-camphor sulfonates of α-hydroxyimino-4-methylbenzyl cyanide, α-hydroxyimino-4-butylbenzyl cyanide -hydroxyimino-3-methylbenzyl cyanide, α-hydroxyimino-2-methylbenzyl cyanide, α-hydroxyimino-2,4-dimethylbenzyl cyanide, α-hydroxyimino-3,4-dimethylbenzyl cyanide, α-hydroxyimino-3,4-dibutylbenzyl cyanide, α-hydroxyimino- 2,4,6-trimethylbenzyl cyanide, α-hydroxyimino-2-chlorobenzyl cyanide, α-hydroxyimino-2,4-dichlorobenzyl cyanide, α-hydroxyimino-4-chlorobenzyl cyanide, α-hydroxyimino-4-fluorobenzyl cyanide.

The oxime sulfonates of the formula I or. Ia are prepared according to methods described in the literature, such as e.g. by reacting suitable free oxims of the formula II with sulfonic acid halides of the formula 3 in the presence of a base such as triethylamine, or by reacting the salt of an oxime with sulfonic acid chloride.

These methods are e.g. published in EP 48615.

1012854 9 * NC NC Ο

\ \ II

C = N - OH + CI-SCL-FL -C = N-0 ~ S-Rfi R R 11

5 R O

<2) (3) (1a) where R R * \ / R '10 r; r5 is and R |, R2, R3, R4, R5 and R <s are as defined above.

The reaction is usually carried out in an inert organic solvent in the presence of a tertiary amine. The sodium salts of the oximes are obtained, for example, by reacting the respective oxime with a sodium alcoholate in dimethylformamide (DMF).

The oximesulfonates are obtained in the syn (E, cis) or anti (Z, trans) form 20 or also as mixtures of the two conformers. According to this invention it is possible to use some conformers as well as any mixture of different conformers. When a single conformer is required, it is obtained from the mixture by conventional methods known to those skilled in the art, such as, for example, crystallization, distillation or chromatography.

The oxims (2) required for the reaction are generally prepared analogously to known methods, such as, for example, by reacting compounds containing reactive methylene groups, such as benzyl cyanide derivatives or phenylacetic acid derivatives, with an alkyl nitrite, e.g. methyl nitrite or isoamyl nitrite, and a sodium alcoholate, for example sodium methanolate. Such reactions are described, inter alia, in "The systematic identification of organic compounds", John Wiley and Sons, New York, 1980, biz. 181, in "Die Makromolekulare Chemie", 1967, 108, 170, or in "Organic Synthesis", 1979, 59, 95.

10 1 2 854 10

Oxims can e.g. also be obtained by reacting a corresponding carbonyl compound or thiocarbonyl compound with hydroxylamine. A further preparation method is nitrosation of hydroxyaromatic compounds.

The preparation of sulfonic acid halides (3) is known to those skilled in the art and is described, for example, in standard chemistry textbooks.

It is an object of this invention to provide photoresists comprising compounds which generate an acid upon irradiation, which compounds have a molar extinction coefficient ε less than 10 at 365 nm. Accordingly, the subject of the invention is a chemically enhanced photoresist sensitive to radiation in the range 340 to 390 nm, comprising a photosensitive acid generator, characterized by a molar extinction coefficient ε less than 10 at 365 nm.

Furthermore, it is an object of this invention to provide photoresists comprising compounds of the formula I or Ia. Accordingly, the subject of the invention is a chemically amplified photoresist sensitive to radiation in the range of 340 to 390 nm, comprising a photosensitive acid generator of the formula I, as defined above, which is characterized by a molar extinction coefficient -center ε less than 10 at 365 nm, as well as a chemically enhanced photoresist sensitive to radiation in the range of 340 to 390 nm, comprising a photosensitive acid generator of the formula Ia, as defined above, which is characterized 20 has a molar extinction coefficient ε less than 10 at 365 nm.

These chemically enhanced photoresists preferably have a thickness of more than 2 µm. Also, the compositions of the invention for irradiation are preferably applied in a thickness of more than 2 µm.

These resists include chemically amplified, negative photoresists that can be developed in an alkaline medium and have a resist thickness greater than 2 µm and are sensitive to radiation in the 340 to 390 nanometer range, which are based on a photosensitive acid generator with a molar extinction coefficient ε less than 10 at 365 nm.

These resists further include, in particular, chemically amplified, negative fo-toresists which can be developed in an alkaline medium and with a resist thickness greater than 2 µm and which are sensitive to radiation in the range of 340 to 390 nanometers, which are based on resists to oximesulfonates as defined above as photosensitive acid generator.

101 2854 11

Another embodiment of the invention relates to chemically enhanced positive photoresists that can be developed in an alkaline medium and have a resist thickness greater than 2 µm and are sensitive to radiation in the range of 340 to 390 nanometers, which are based on oxime sulfonates as defined above as photosensitive acid.

Both embodiments of the photoresists of the invention can easily decompose structural units with dimensions in the submicron region, the radiation used being in the range of 340 to 390 nanometers. The resist structures remaining on the substrate after development show very good style of the side walls. Despite the extremely low optical absorption, the resists also have an excellent sensitivity to the given radiation. This feature is especially unexpected since the oximesulfonates selected as acid generators absorb radiation of this wavelength only in a very small amount. In addition, the negative resists in particular have the additional advantage of exhibiting improved thermal resistance, which is favorable for ion implantation processes.

The present invention also relates to the use of compounds of the formula I or Ia, with a molar extinction coefficient ε less than 10, as photoacid generators in compositions comprising compounds which can be cross-linked by the action of an acid or / and as solution inhibitors for compounds whose solubility changes under the action of an acid, wherein the exposure is performed, for example, imagewise, as well as a method of generating acids, wherein a photoacid generator of the formula I or Ia, with a molar extinction coefficient ε less than 10 , is irradiated with light of a wavelength in the range of 340-390 nm.

In light-curable compositions, oximesulfonic acid esters act as latent curing catalysts: upon irradiation with light, they generate acid which catalyzes the crosslinking reaction. In addition, the radiation-generated acid can catalyze, for example, the removal of suitable acid-sensitive protecting groups from a polymer structure or the cleavage of polymers containing acid-sensitive groups in the polymer backbone. Other applications include, for example, color change systems based on a change in the pH or solubility of, for example, a pigment protected by protecting groups sensitive to acid f01285412. Compositions using pH sensitive dyes or latent pigments in combination with oximesulfonates can be used as light indicators or simple disposable dosimeters. Particularly for light invisible to the human eye, such as UV or IR light, such dosimeters are important.

The oximesulfonates of the present invention can also be used to shape polymers that undergo an acid-induced transition in a state where they have the required properties by photolithography. For example, the oximesulfonates can be used to pattern conjugated emission polymers as described in M.L. Renak; C. Bazan; D. Roitman; Advanced Materials 1997, 9, 392. Such patterned emission polymers can be used for the production of microscalar, patterned Light Emitting Diodes (LED), which can be used for the production of displays and data storage media. Likewise, polyimide precursors (eg, polyimide precursors having acid-labile protecting groups that change solubility during development) can be irradiated to form patterned polyimide layers that can serve as protective coatings, insulating layers and buffer layers in the production of microchips and printed circuit boards.

It is known from the literature that conjugated polymers such as e.g. polyanilines can be converted into the conductive state by doping with a proton from the semiconductor. The oximesulfonates of the present invention can also be used as acid generators for imagewise irradiating such conjugated polymers to selectively perform such conversion in the exposed areas.

Oximesulfonic acid esters sparingly soluble in an aqueous alkaline developer can be solubilized in the developer by light-induced conversion to the free acid, with the result that they are used as solution inhibitors in combination with suitable film-forming resins.

Resins that can be cross-linked by acid catalysis are, for example, mixtures of polyfunctional alcohols or hydroxyl groups containing acrylic and polyester resins, or partially hydrolysed polyvinyl acetals or polyvinyl alcohols with polyfunctional acetal derivatives. Under certain conditions, for example, the acid-catalyzed autocondensation of acetal functionalized resins is also possible.

In addition, the oximesulfonates e.g. used as curing agents that can be activated by light for resins containing siloxane groups. For example, these resins can either undergo autocondensation by acid-catalyzed hydrolysis or cross-link with a second resin component, such as a polyfunctional alcohol, a hydroxyl-containing acrylic or polyester resin, a partially hydrolysed polyvinyl acetal or a polyvinyl alcohol. This type of polycondensation of polysiloxanes is described, for example, in J.J. 10 Lebrun, H. Pode, Comprehensive Polymer Science, Vol. 5, page 593, Pergamon Press, Oxford, 1989.

It is clear that the acid initiated reactions, as described above in the context of the present invention, can be carried out not only with oxime sulfonate compounds as acid generators, but also with other acid generating compounds with a molar extinction coefficient ε less than 10. Examples of such compounds are listed above.

As already mentioned above, the difference in solubility between irradiated and non-irradiated sections that occurs due to the acid-catalyzed reaction of the resist material during or after the irradiation of the resist may depend on the further ingredients present in the formulation or the resist are of two types. If the compositions of the invention comprise components that increase the solubility of the composition in the developer, the resist is positive. On the other hand, if these components decrease the solubility of the composition, the resist is negative.

Acid sensitive components that produce a negative resist are in particular compounds which, upon catalysis with an acid (eg the acid formed during the irradiation of the compound of the formula I or Ia), are capable of a cross-linking reaction with itself or with one or more further components of the composition. Compounds of this type are, for example, the known under the influence of acid-curable resins, such as, for example, acrylic, polyester, alkyd, melamine, urea, epoxy and phenolic resins or mixtures thereof. Amino resins, phenolic resins and epoxy resins are very suitable. Acid-curable resins of this type are well known and are described, for example, in Ullmann's Encyclopedia 101 2 854 '. 14 of Technical Chemistry, fourth edition, volume 15 (1978), pp. 613-628. The resins are generally present in a concentration of 2 to 40% by weight, preferably 5 to 30% by weight, based on the total solids content of the negative resist composition.

Particularly preferred as acid-curable resins are amino-5 resins, such as unetherified or etherified melamine, urea, guanidine or biur resins, preferably methylated melamine resins or butylated melamine resins, corresponding glycolurils and urons. Resins are the usual technical mixtures in this context, which usually also include oligomers as well as pure and very pure compounds. N-methoxymethylmelamine (Formula 7) and tetramethoxy-10 methylglucoril (Formula 8) and Ν, Ν'-dimethoxymethyluron (Formula 9) are the most preferred acid-curable resins in the context of the present application.

CHaOCH2 CH2OCH3

N- (CH 2 OCH 3) 2. I

jf N - ^ - N

15 N ^ N (7); 0 = <T> = 0 (8);

^ X ^ N

(CH3OCH2) —N N N— (CH2OCH3) 2 CH3OCH2 CH2OCH3

O

CH3OCH2v X CH2OCH3 20 3 2 N N (9).

O

The concentration of the acid-generating compound in general and in particular the concentration of the compound of the formula I, respectively. Ia in negative resists is usually 0.1 to 30% by weight, preferably 0.1 to 20% by weight, based on the total solids content of the composition. A concentration of 1 to 15% by weight is particularly preferred.

If applicable, the negative compositions may additionally comprise a film-forming polymeric binder. This binder is preferably an alkali-soluble phenolic resin. Well suited for that purpose are, for example, novolacs derived from an aldehyde, usually acetaldehyde or furfuraldehyde, but in particular from formaldehyde, and a phenol, for example unsubstituted phenol, phenol substituted once or twice, such as p-chlorophenol, phenol which is substituted once or twice 1012854 with C 1 -C 9 alkyl, such as o-, m- or p-cresol, the different xylenols, p-tert-butylphenol, p-nonylphenol, p-phenylphenol, resorcinol, bis (4- hydroxyphenyl) methane or 2,2-bis (4-hydroxyphenyl) propane. Also suitable are homo- and copolymers based on ethylenically unsaturated phenols, such as, for example, homopolymers of vinyl and 5-propenyl-substituted phenols, such as p-vinylphenol or p- (1-propenyl) phenol, or copolymers of these phenols with one or more than one ethylenically unsaturated compound, for example styrenes. The amount of binder generally ranges from 30 to 95% by weight or, preferably, 40 to 80% by weight.

The invention as a special embodiment comprises negative photoresists with a resist thickness greater than 2 µm which can be developed in an alkaline medium for an operating radiation of a wavelength between 340 and 390 nanometers, comprising an oximesulfonate of the formula Ia as described above, an in alkali soluble phenolic resin as a binder and a component which, upon catalysis with an acid, undergoes a cross-linking reaction with itself and / or with the binder.

Particularly preferred negative photoresists include 1 to 15 wt% oxime sulfonate as an acid generating agent, 40 to 99 wt% of a phenolic resin as a binder, for example one of the above-mentioned phenolic resins, and 0.5 to 30 wt% of a melamine resin as a cross-linking agent, the percentages refer to the solid content of the composition. The use of novolak 20 or, in particular, polyvinylphenol as a binder gives a negative resist with particularly good properties.

It is preferred to use a negative resist comprising N-methoxymethyl-melamine or tetramethoxymethylglucoril and Ν, Ν'-dimethoxymethyluron in high purity or in technical form as an amino resin.

Oxime sulfonates are also used as acid generators which can be photochemically activated for the acid catalyzed cross-linking of, for example, poly (glycidyl) methacrylates in negative resist systems. Such cross-linking reactions are described, inter alia, by Chae et al. In Pollimo 1993, 17 (3), 292.

Monomeric or polymeric compounds which are not alkali-soluble but are cleaved in the presence of an acid, or which can be rearranged intramolecularly in such a way that residual products remain which are soluble in a conventional alkaline developer and / or which cause an otherwise non-alkali-soluble and acid-resistant additional binder becoming soluble in the developer also give a positive feature in the new photoresist compositions of the invention. Substances of this type are referred to herein as solution inhibitors.

The invention therefore, as a further special embodiment, comprises positive photoresists that can be developed in an alkaline medium for an operating radiation of a wavelength of 340 to 390 nanometers, comprising a compound of the formula I, respectively. Ia, with a molar extinction coefficient ε less than 10, and at least one compound which substantially prevents the composition from dissolving in an alkaline developer, but which can be cleaved in the presence of an acid so that the remaining reaction products are soluble in the developer and / or which causes an acid-resistant additional binder that is otherwise practically insoluble in the developer to dissolve in the developer.

As solution inhibitors, monomeric and polymeric organic compounds with functional groups that are soluble as such in an alkaline medium can be used, for example aromatic hydroxyl groups, carboxylic acid groups, secondary amino groups and keto or aldehyde groups. These monomeric and polymeric organic compounds have been chemically altered prior to their use as solution inhibitors by reaction with a suitable compound so that they are insoluble in aqueous alkali, the protecting group formed during said reaction being capable of being cleaved by acid in such a manner catalysis, that the functional groups are recovered in their original form.

Suitable protective groups for the protection of hydroxyl groups, carboxylic acid groups or secondary amino groups are, for example, dihydrofuran or 3,4-dihydropyran and its derivatives, benzyl halides, alkyl halides, haloacetic acids, haloacetates, chlorocarbonates, alkylsulfonylhalides, aromatic sulfonylhalides, dialkyldicarbonates. The protecting groups are introduced by conventional reactions known to a person skilled in the art. The usual conversion to ketals and acetals is suitable for protecting keto and aldehyde groups. Such chemically enhanced positive resist systems are described, inter alia, in E. Reichmanis, F.M. Houlihan, O. Nalamasu, T.X. Neenan, Chem. Mater. 1991, 3, 394; or in C.G. Wilson, "Introduction to Microlithography, Second Edition; L.S. Thompson, C.G. Willson, M.J. Bowden, Eds., Amer. Chem. Soc., Washington DC, 1994, 139.

101 2 8 5 4% 17

Compounds containing blocked aromatic hydroxyl groups are particularly preferred, where the compounds may be monomers or polymers.

The aromatic monomers preferably contain one or more than one aromatic nucleus, preferably 2 to 6 aromatic nuclei, containing 6 to 14, preferably 6, carbon 5 atoms in the ring. In addition to the blocked hydroxyl groups, the aromatic core can of course contain further substituents, such as preferably C 1 -C 4 alkyl, C 1 -C 4 alkoxy or halogen. Particularly preferred monomeric solution inhibitors are bisphenyl species, i.e. compounds of the formula 10 / - \

Y — z - ^ - Y

each Y being an acid sensitive group, such as a phenolic hydroxyl group, which is protected by a suitable acid sensitive group such as the ether, carbonate, silyl, tetrahydropyranyl or tetrahydrofuranyl groups (see eg EP 475903), and Z is either a direct bond or one of the radicals: -S-; -O-; -SO-; -SO2-; -CO-; -C (Ra) (Rb) - wherein Ra is hydrogen, methyl or aryl and Rb is hydrogen or methyl. Particularly preferred bivalent radicals -C (Ra) (Rb) - are -CH2-; -C (CH3) 2- and C (CH3) (Ph) -. The preferred polymeric solution inhibitors are derived from conventional phenolic resins, usually from polyvinylphenols, the hydroxyl groups of which are also blocked in a manner consistent with the above description. Solution inhibitors containing protecting groups of the type shown are known in the art. Inhibitors containing carbonate groups are described, inter alia, by Dennis R.

McKean, Scott A. MacDonald, Nicholas J. Clecak and C. Grant Wilson in Novolac based deep-UV resists, SPIE volume 920 Advances in Resist Technology and Processing V (1988), biz. 60-63, or by Masamitsu Shirai and Masahiro Tsunooka in "Photochemistry of Imino Sulfonate Compounds and their Application to Chemically Amplified Resists", Journal of Photopolymer Science and Technology, vol. 3 (3), 1990, biz.

30 301-304. The solution inhibitors containing protecting groups can be prepared according to known standard methods, such as described for example by J.M.J. Frechet, E. Eichler, H. Ito, and C.G. Willson, Polymer 24 (1983), biz. 995. Solution inhibitors containing trialkylsilyloxy or tert-butyloxy groups are described in EP 0329610, inhibitors containing protecting groups of the type of the tetrahydrofuranyl and tetrahydropyranyl groups are described, inter alia, by N. Hayashi, S.M.A. Hesp, T. Ueno, M. Toriumi, T. Iwayanagi and S. Nonogaki in Polym. Mat. Sci. Scary. 61 (1989), pp. 417-421. Aromatic compounds containing substituted tetrahydropyranyl groups are described in more detail in EP 0475903. The protecting groups can be obtained in a manner known to one skilled in the art by the addition of 3,4-dihydropyran or 3,4-dihydrofuran under acidic conditions.

In positive resists of the mentioned type, a fim-forming polymeric solution inhibitor can be either the only binder in the photoresist or it can be mixed with an acid inert binder and, if applicable, a monomeric solution inhibitor.

Examples of acid-inert binders are novolacs, in particular those based on o-, m- or p-cresol and formaldehyde, also poly (p-hydroxystyrene), poly (p-hydroxy-a-methylstyrene) and copolymers of p-hydroxystyrene, p-hydroxy-α-methylstyrene and acetoxystyrene.

Examples of polymeric solution inhibitors are novolacs, in particular those based on o-, m- or p-cresol and formaldehyde, poly (p-hydroxystyrene), poly (p-hydroxy-a-methylstyrene), copolymers of p-hydroxystyrene or p-hydroxy-α-20 methylstyrene and acetoxystyrene or acrylic acid and / or methacrylic acid and also (meth) -acrylic acid esters which have reacted in known manner with dihydrofuran, 3,4-dihydropyran, benzyl halides, alkyl halides, haloacetic acid, haloacetates, chlorocarbonates alkylsulfonyl halides, aromatic sulfonyl halides, dialkyl dicarbonate or trialkylsilyl halides. Also suitable are polymers of p- (2-25 tetrahydropyranyl) oxystyrene or p- (tert-butyloxycarbonyl) oxystyrene with (meth) -acylic acid, (meth) acylates and / or p-acetoxystyrene and polymers of p-hydroxystyrene and / or p - (2-tetrahydropyranyl) oxystyrene with 3-hydroxybenzyl (meth) acrylates, which, if necessary, can additionally be protected by reaction with one of the above-mentioned compounds.

Particularly suitable are polymers which are transparent over a wavelength range of 180 to 1000 nm and which contain groups which, after acid-catalyzed removal of the protecting group, cause a change in the solubility, as well as hydrophobic and hydrophilic groups which improve the solubility of the acid generator 10 1 2854 19 and which ensure developability in aqueous-alkaline media. Examples of such polymers are acrylates and methacrylates prepared by copolymerization or terpolymerization from the respective monomers. The monomers can also contain organosilicon residues in order, for example, to increase the resistance in the case of dry etching processes. Examples of relevant monomers are: methyl (meth) acrylate, (meth) acrylic acid, tert-butyl (meth) acrylate, trimethylsilylmethyl (meth) acrylate, 3-oxocyclohexyl (meth) acrylate, tetrahydropyranyl (meth) acrylate, adamantyl ( meth) acrylate, cyclohexyl (meth) acrylate, norbomyl (meth) acrylate.

Accordingly, the invention also relates to a chemically strengthened positive resist comprising, as a photosensitive acid generator, a compound of the formula I or Ia, with a molar extinction coefficient ε less than 10, as well as a photoresist comprising polymers that are transparent up to the wavelength range of 180 nm.

A special embodiment of the positive resist according to the invention comprises 75 to 99.5 wt% of a film-forming polymer containing protective groups that can be removed by acid catalysis, and 0.5 to 25 wt% oxime sulfonates of the formula I or Formula Ia, with a molar extinction coefficient ε less than 10, the percentages being based on the solids content of the compositions. In this context, preference is given to compositions containing 80 to 99% by weight of said polymer and 1 to 20% by weight of oximesulfonate.

Another embodiment is a positive resist comprising 40 to 90% by weight of an acid inert film-forming polymer as a binder, 5 to 40% by weight of a monomeric or polymeric compound with protecting groups that can be removed by acid catalysis and 0, 5 to 25 wt% oxime sulfonates of the formula I or Ia, 25 as described above, the percentages refer to the solids content of the compositions. Preference is given to compositions comprising 50 to 85% by weight of the acid inert binder, 10 to 30% by weight of the monomeric or polymeric solution inhibitor and 1 to 15% by weight of oxime sulfonates.

Oxime sulfonates can also be used as solubilizers which can be activated by light. In that case, the compounds are added to a film-forming material that contains virtually no components that polymerize with the oximesulfonate when heated or irradiated with actinic radiation. However, the oximesulfonates decrease the rate at which the film-forming material dissolves in a suitable developer medium. This inhibiting effect can be negated by irradiating the mixture with actinic radiation, so that a positive image can be produced. Such an application is described, for example, in EP 241423.

A further special embodiment of the invention is a positive resist comprising a compound of the formula I or Ia, with a molar extinction coefficient ε less than 10, and a binder which is practically insoluble in an alkaline developer and which, in the presence of the photolysis products of the compound of formula I or Ia becomes soluble in the developer. In this case, the amount of said oximesulfonate compound of the formula I or Ia is generally 5 to 50% by weight, based on the solids content of the composition.

The use of the oxidesulfonates of the invention in chemically enhanced systems operating on the principle of removing a protecting group from a polymer generally produces a positive resist. Positive resists are preferred over negative resists in many applications, especially because of their better resolution. However, there is also interest in producing a negative image using the positive resist mechanism in order to combine the advantages of the high resolution of the positive resist with the properties of the negative resist. This can be achieved by introducing a so-called image reversal step, as is described, for example, in EP 361906. To this end, the image-irradiated resist material is treated with e.g. a gaseous base, whereby the acid produced imagewise is neutralized. Then, a second irradiation, over the entire area, and a thermal post-treatment are performed, and the negative image is finally developed in the usual manner.

In addition to said components, it is also possible to add compounds that accelerate or enhance acid formation to the oximesulfonate-containing negative as well as positive photoresist compositions. Such acid enhancers are described, inter alia, in K. Arimitsu et al., J. Photopolym. Sci. Technol. 1995, 8, 30 p. 43, Kudo K et al., J. Photopolym. Sci. Technol. 1995, 8, p. 45 or K. Ichimura et al., Chem. Lett. 1995, p. 551.

In addition to the aforementioned ingredients, both the negative and positive photoresist compositions may further comprise one or more of the additives commonly used

ItO 12? 21 ft. Used in photoresists in the amounts known to one skilled in the art. Examples of such additives are flow control agents, wetting agents, adhesives, thixotropic agents, dyes, pigments, fillers, dissolution accelerators and so on. However, substances that make the compositions additionally sensitive to the effective radiation in the mercury i line range should not be added, as this usually results in a reduced resist resolution.

For certain purposes, resin mixtures with monomeric or oligomeric components containing polymerizable unsaturated groups are added. Such surface coatings can also be cured using the compounds of formula I or 11 as described above. In addition to component c), it is possible to use 1. radical polymerization initiators or 2. photoinitiators. The former initiate the polymerization of the unsaturated groups by heat treatment, the latter by UV radiation. Examples of additional photoinitiators 15 for use in the compositions of the invention are, for example, radical

photoinitiators, usually those of the class of the benzophenones, acetophenone derivatives, such as α-hydroxycycloalkylphenyl ketone, dialkoxyacetophenone, α-hydroxyacetophenone or α-aminoacetophenone, 4-aroyl-1,3-dioxolane, benzoalkylethyl and benzyl ketals, phenyl ketal acids, phenyl ketals dimer phenylglyoxalic acid esters, peresters, e.g. benzophenone tetracarboxylic acid esters described, for example, in EP

126541, monoacylphosphine oxides, bisacylphosphine oxides or titanocenes. Illustrative examples of particularly suitable additional photoinitiators are: 1- (4-dodecylbenzoyl) -1-hydroxy-1-methyl-ethyl, 1 - (4-isopropylbenzoyl) -1-hydroxy-1-methyl-1-benzyl-1-hydroxy -1-methyl ethyl, 1 - [4- (2-hydroxyethoxy) benzoyl] -1-hydroxy-1 -25 methyl ethyl, 1- [4- (acryloyloxyethoxy) benzoyl] -1-hydroxy-1-methyl ethyl, diphenyl ketone, phenyl-1-hydroxycyclohexyl ketone, (4-morpholinobenzoyl) -1-benzyl-1-dimethyl-aminopropane, 1- (3,4-dimethoxyphenyl) -2-benzyl-2-dimethylaminobutane-1-one, (4-methylthiobenzoyl) - 1-methyl-1-morpholinoethane, benzildimethyl ketal, bis (cyclopenta-dienyl) bis (2,6-difluoro-3-pynylphenyl) titanium, trimethylbenzoyldiphenylphosphienoxide, 30 bis (2,6-dimethoxybenzoyl) - (2,4,4- trimethylpentyl) phosphine oxide, bis (2,4,6-trimethyl-

benzoyl) -2,4-dipentoxyphenylphosphine or bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide. Other suitable additional photoinitiators are described, for example, in US

10 1 2854 22 4950581, column 20, line 35 to column 21, line 35. Other examples are tri-halomethyltriazine derivatives or hexa-aryl bisimidazolyl compounds.

Further examples of additional photoinitiators are also cationic photoinitiators, usually peroxide compounds, such as benzoyl peroxide (other suitable peroxides are described in US 4950581, column 19, lines 17-25), aromatic sulfonium salts or iodonium salts, such as those which include described in US 4950581, column 18, line 60 to column 19, line 10, or cyclopentadienyl-arene-iron (II) complex salts, usually (η 6-isopropylbenzoyl) (r | 5-cyclopentadienyl) iron (II) hexafluorophosphate.

Before application, the compositions generally also comprise a solvent. Examples of suitable solvents are acetone, methyl ethyl acetate, ethyl acetate, 3-methoxymethyl propionate, ethyl pyruvate, 2-heptanone, diethyl glycol dimethyl ether, cyclopentanone, cyclohexanone, γ-butyrolactone, ethyl methyl ketone, 2-ethoxyethanol, 2-ethoxyethyl acetone methoxy-2-propyl acetate or propylene glycol methyl ether acetate. The solvent can also be added as a mixture of, for example, two or more of the above-mentioned solvents. The choice of the solvent and the concentration depend, for example, on the nature of the composition and on the coating method.

The solution is evenly applied to a substrate by known coating methods, such as, for example, spin coating, dipping, iron coating, curtain coating techniques, brush application, spraying and reverse roll coating. It is also possible to apply the photosensitive layer to a temporary flexible support and then coat the final substrate by coating transfer (laminating).

The amount applied (coating thickness) and the nature of the substrate (coating substrate) depend on the desired field of application. The coating thickness range may in principle comprise values from about 0.1 µm to more than 100 µm, but in the context of the present invention, values> 2 µm are particularly preferred. Particular preference is given to coating thicknesses from 2 µm to 100 µm, for example 2.5 µm to 60 µm or 2.5 µm to 20 µm.

Possible fields of application of the composition according to the invention are as follows: application as photoresists for electronics, such as etching resists, galvanizing resists or solder resists, the manufacture of integrated circuits or thin film transistor resist (TFT resist) ), the manufacture of printing plates, such as offset printing plates or screen printing plates, use in etching of molding products or in stereo lithography techniques, use in door filters or image recording materials and all other types of lithographic imaging processes and preferably use as microresist in integrated circuit fabrication. The coating substrates and processing conditions vary according to the application and are common in the art.

When using the compositions as microresists for integrated and large-scale integrated circuits, as preferred, the layer thickness is usually 2 to 30 µm, preferably 2 to 10 µm. Preferably use is made of process steps in which the relatively large thickness results in certain advantages or is required to obtain the desired functionality. An example of such application is ion implantation resists with coating thicknesses usually ranging from 2 to 10 µm, preferably 2 to 7 µm.

The compositions according to the invention are also extremely suitable as coating compositions for all kinds of substrates, including wood, textile, paper, ceramic, glass, plastics, such as polyesters, polyethylene terephthalate, polyolefins or cellulose acetate, in particular in the form of films and in particular for coating metals, such as Ni, Fe, Zn, Mg, Co or in particular Cu and Al, and also 20 Si, silicon oxides or nitrides, to which an image is to be applied by image-wise irradiation . The meaning of the term "imagewise" irradiation is explained below.

After the coating operation, the solvent is generally removed by heating, resulting in a layer of the photoresist on the substrate. The drying temperature should, of course, be lower than the temperature at which certain components of the resist thermally cure. In that regard, particular care should be taken in the case of negative photoresists. Generally, the drying temperatures range from 80 to 140 ° C.

The resist coating is then irradiated imagewise. This irradiation in a predetermined pattern using actinic radiation includes both irradiation through a photomask containing a predetermined pattern, for example a slide positive, as well as irradiation with a laser beam that is moved over the surface of the coated surface. , for example under the control of a computer, and thus gives an image.

Suitable radiation sources are those which emit radiation of a wavelength in the operating range of the resist, for example between 340 and 390 nanometers.

5 Both point sources and planar projectors (series of reflector lamps) are suitable. Examples are: carbon arc lamps, xenon arc lamps, medium pressure, high pressure and low pressure mercury lamps, optionally doped with metal halides, metal halide lamps), microwave excited metal vapor lamps, excimer lamps, superactinic fluorescent tubes, fluorescent lamps, argon filament lamps, electronic flash lamps, photographic spotlights, electron beams and X-rays generated by synchotrons or laser plasma. Particularly suitable are mercury vapor lamps, in particular medium and high-pressure mercury lamps, from whose radiation the emission lines are filtered out at other wavelengths if desired. This is particularly the case with short wavelength radiation. The distance between the lamp and the substrate to be irradiated according to the invention can, for example, vary from 2 cm to 150 cm according to the intended application and the type and / or the strength of the lamp. A suitable laser beam source is, for example, an argon ion laser, which emits radiation with wavelengths of 364 and 388 nanometers. With that type of irradiation, it is not absolutely essential to use a photomask in contact with the photopolymer coating; the controlled laser beam can write directly on the cladding. To this end, the high sensitivity of the materials according to the invention is very advantageous, while high writing speeds at relatively low intensities are possible. Upon irradiation, the oximesulfonate in the composition decomposes in the irradiated sections of the surface coating to form sulfonic acids. When using lamps emitting light in a wavelength range that exceeds the range of 340-390 nm, the effective wavelength is selected by using filtering equipment. In general, interference filters are used.

After the irradiation and, if desired, the thermal treatment, the irradiated areas (in the case of positive resists) or the irradiated areas (in the case of negative resists) of the composition are removed in a known manner with the aid of a developer.

Generally, a certain period of time is required before the development step for the acid sensitive components of the resist composition to react. For accelerating this reaction and thus the development of a sufficient difference in solubility between the irradiated and non-irradiated areas of the resist coating in the developer, the coating is preferably heated before developing. Heating can also be performed or started during the irradiation. Preferably temperatures of 60 to 160 ° C are used. The length of time depends on the mode of heating and if desired, the optimal period can be easily determined by a skilled person using a few routine experiments. It is generally from a few seconds to several minutes. For example, a period of 10 to 300 seconds is very suitable if a hot plate is used, and 1 10 to 30 minutes if a convection oven is used

Then, the coating is developed, removing the parts of the coating that are more soluble in the developer after irradiation. If necessary, a little shaking of the workpiece, gentle brushing of the coating in the developing bath or spray development can accelerate the process step. The aqueous-alkaline developers common in the resist technology can be used for development. Such developers include, for example, sodium or potassium hydroxide, the corresponding carbonates, acid carbonates, silicates or metasilicates, but preferably metal-free bases, such as ammonia or amines, for example ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethyl-20 amine, methyl diethylamine, alkanolamines, for example dimethylethanolamine, triethanolamine, quaternary ammonium hydroxides, for example tetramethylammonium hydroxide or tetraethylammonium hydroxide. The developing solutions generally have a concentration of up to 0.5 N, but are generally diluted appropriately before use. For example, solutions with a normality of about 0.1 are extremely suitable. The choice of the developer depends on the nature of the photoresist, in particular on the nature of the binder used or the photolysis products obtained. The aqueous developing solutions may also contain relatively small amounts of wetting agents and / or organic solvents, if desired. Common organic solvents that can be added to the developer fluids are, for example, cyclohexanone, 2-ethoxyethanol, toluene, acetone, isopropanol, and also mixtures of two or more of these solvents. A common aqueous / organic development system is based on BUTYL-CELLOSOLVE® / water.

TO 1 2 854 26

Accordingly, this invention also relates to a method of producing an image comprising (a) coating a substrate with a composition as described above, (b) irradiating the coating with radiation of a wavelength of 340 to 390 nanometers in a desired pattern and, after a heating period at temperatures from 60 to 160 ° C (c), (d) removing the more soluble areas of the coating with an aqueous alkaline developer.

In another of its aspects, this invention also relates to the use of the compositions described above in the production of printing plates, color filters, resist materials and image recording material, as well as the use of such compositions in the production of printing plates, color filters, resist materials or image recording materials. , or for image recording materials for holographic images, as well as for the use of compounds of the formula I or Ia, with a molar extinction coefficient 8 of less than 10, as a photosensitive acid generator for radiation of a wavelength smaller than 390 nm in the production of printing plates, 15 color filters, resist materials or image recording materials, or for image recording materials for holographic images.

In addition to a color change, the pigment crystals may precipitate during the acid-catalyzed removal of the protecting groups of soluble pigment molecules; this can be used in the production of color filters.

The compounds of the formula I resp. Ia are usually in an amount of 0.1 to 30% by weight, e.g. 0.5 to 20% by weight, preferably 1 to 10% by weight, are added to the compositions which can be activated by light.

A subject of the invention is also a negative photoresist, which as an acid generating compound of the formula la a- (methanesulfoniumoxyimino) -3,4-dimethylphenylacetonitrile, a- (methanesulfoniumoxyimino) -4-methylphenylacetonitrile or a- (4-toluenesulfoniumoxyimino) phenylacetonitrile.

The invention is illustrated in more detail in the following examples. As in the rest of the description and claims, parts and percentages, unless stated otherwise, are by weight 10 1 2 854 27

Example I:

A negative resist composition is prepared by mixing 70 parts by weight of polyvinylphenol resin (Maruzen Chemical Co. Ltd), 25 parts by weight of hexamethoxymethyl melamine, CYMEL-303® (American Cyanamide) and 150 parts by weight of propylene glycol ethyl ether acetate.

Separately, 5 parts by weight of the acid generating agent represented by α- (methanesulfoniumoxyimino) -3,4-dimethylphenylacetonitrile (with 10 an ε of 4.1 in a tetrahydrofuran solution at 365 nm) is dissolved in 10 parts by weight of N, N-dimethylacetamide.

Both solutions are mixed to form the resist solution.

A silicon wafer is coated evenly with the resist solution thus prepared, using a spin device, followed by drying for 90 seconds at 110 ° C, whereby a dried photoresist layer having a thickness of 5 µm is obtained. The resist layer is exposed with a mask aligner (Canon PLA501) using the interference filter to select the i-line, 365 nm), followed by baking at 110 ° C for 90 seconds after exposure. The resulting formulation is subjected to a development treatment in a 2.38 wt% aqueous solution of tetramethyl-20 ammonium hydroxide for 60 seconds, then washed with water and air dried.

The line-and-space photosensitivity of 2 µm, represented by the exposure doses at which the resist layer could be fully formed on the exposed areas at a ratio of 1: 1, was 210 mJ / cm2 (energy).

Furthermore, a resist layer patterned with a line-and-space pattern with a line width of 2 µm is formed in the same manner as above and examined with a SEM (scanning electron microscope) for the cross-sectional profile of the line pattern . It has been found that the cross section has a rectangular shape that is perpendicular to the substrate. The relative width of the line made by varying the exposure dose between 0.8 and 1.2 times against the sensitivity to light obtained above is plotted against the supplied energy. The slope of the best-fit straight line through the points is 0.28. The smaller the slope, the better the exposure latitude of the tested system.

101 2 894 28

Example II:

A resist formulation according to Example I is prepared. However, as the acid generating agent, instead of a- (methanesulfoniumoxyimino) -3,4-dimethylphenylacetoni-5, 5 parts by weight of a- (methanesulfoniumoxyimino) -4-methylphenylacetonitrile (with an ε of 0.35 in a tetrahydrofuran solution at 365 nm) is used .

Under the same conditions as described in Example I, the obtained sensitivity to light is 300 mJ / cm2. The cross-sectional profile of the resist layer with a line width of 2 µm, examined with an SEM (scanning electron microscope), is a rectangular shape perpendicular to the substrate. The slope, determined in the same manner as in Example 1, is 0.31.

Example ΙΠ: 15 A resist formulation according to Example I is prepared. As the acid generating agent, however, 5 parts by weight of a- (4-toluenesulfoniumoxyimino) phenylacetomtril (with an ε of 0.28 in a tetrahydrofuran solution at 365 nm) is used instead of α- (methanesulfoniumoxyimino) -3,4-dimethylphenylacetoni trill.

Under the same conditions as described in Example I, the sensitivity to light obtained is 500 mJ / cm2. The cross-sectional profile of the resist layer with a line width of 2 µm, examined with a SEM (scanning electron microscope), is a rectangular shape perpendicular to the substrate. The slope is 0.42.

25 Comparative example:

A resist solution was prepared in much the same manner as described in Example I, except that the acid generating agent was replaced with 5 parts of a- (methanesulfoniumoxyimino) -2-thiophenylacetonitrile with an ε of 58 in a tetrahydro-furan solution at -365 nm . The result of the evaluation is a sensitivity to light of 60 mJ / cm2 and a slope of 0.72.

10 1 2 854

Claims (15)

A composition which can be activated by light, comprising (a) at least one compound which can be cross-linked by the action of an acid 5 and / or (b) at least one compound whose solubility changes under the action of an acid and (c) as a photoinitiator at least one compound which is a structural unit of the formula I. comprises 10 \ C = N-0-SO 2 (|) j 15 which generates an acid under the exposure to light with a wavelength of 240 to 390 nm and with a molar extinction coefficient ε less than 10 at the i-line (365 nm ). 2. A composition according to claim 1, comprising as component (c) a compound of the formula Ia 20 NC R, \ c = n-o-so2-r, R <wherein R 1, R 2, R 3, R 1, and R 5 are independently hydrogen or unsubstituted or halogen-substituted C 1 -C 12 alkyl; or R1, R2, R3, R4 and R5 are halogen; R 1 is unsubstituted or halogen-substituted C 1 -C 6 akyl, phenyl-C 1 -C 3 alkyl, camforyl, phenyl, naphthyl, anthracyl, or phenanthryl, wherein the radicals phenyl, naphthyl, anthracyl, and phenantiyl are unsubstituted or substituted with one or more of the radicals 1 2 854 halogen, C 1 -C 4 haloalkyl, CN, NO 2, C 1 -C 16 alkyl, phenyl, OR10, COOR9, -0 (C0) -C 1 -C 4 alkyl, SO2OR9 and / or with NR7R8; R7 and Re are independently hydrogen or C1-C12 alkyl, which is unsubstituted or substituted with OH, C1-C4 alkoxy, C1-C12 alkylsulfonyl, phenylsulfonyl, (4-5 methylphenyl) sulfonyl and / or with C1 -Ce alkanoyl; or R7 and R8 are C2 -C12 alkyl interrupted by -O- and unsubstituted or substituted with OH, C1 -C4 alkoxy, C1 -C12 alkylsulfonyl, phenylsulfonyl, (4-methylphenyl) sulfonyl and / or with C1 -Ce alkanoyl; or R 7 and R 5 are phenyl, C 2 -C 6 alkanoyl, benzoyl, C 1 -C 6 alkylsulfonyl, phenylsulfonyl, (4-methylphenyl) sulfonyl, naphthylsulfonyl, anthracylsulfonyl or phenanthrylsulfonyl; 10 or R7 and Rg, together with the nitrogen atom to which they are attached, form a 5,6 or 7-membered ring which may be interrupted by -O- or by -NRi 1-; R9 is C1-C12 alkyl which is unsubstituted or substituted with OH and / or with C1-C4 alkoxy, or R9 is C2-C12 alkyl which is interrupted by -O- and which is unsubstituted or substituted with OH and / or with C1 -C4 alkoxy; R 10 is hydrogen or C 1 -C 12 alkyl, which is unsubstituted or substituted with phenyl, OH, C 1 -C 12 alkoxy, C 1 -C 12 alkylsulfonyl, phenylsulfonyl, (4-methylphenyl) sulfonyl and / or with C 2 -C 6 alkanoyl; or R10 is C2-C12 alkyl interrupted by -O- and unsubstituted or substituted with phenyl, OH, C1-C12 alkoxy, C1-C12 alkylsulfonyl, phenylsulfonyl, (4-methylphenyl) sulfonyl and / or with C2- C6 alkanoyl; or R10 is phenyl; R 1 is hydrogen, unsubstituted or OH-substituted C 1 -C 12 alkyl or C 2 -C 12 alkyl interrupted by -O-; and wherein the compounds of formula la are characterized by a molar extinction coefficient ε less than 10 at 365 nm. A chemically amplified photoresist that is sensitive to radiation in the range of 340 to 390 nm, comprising a photosensitive acid generator of the formula I as defined in claim 1, characterized by a molar extinction coefficient ε less than 10 at 365 nm . A chemically enhanced photoresist according to claim 3 which is sensitive to radiation in the range from 340 to 390 nm, comprising a photosensitive acid generator of the formula Ia, as defined in claim 2, characterized by a molar extinction coefficient ε less than 10 at 365 nm. 1012854 A chemically enhanced photoresist according to claim 3 or 4 with a thickness of more than 2 μιη. Chemically enhanced negative photoresist, comprising a compound of the formula Ia, with a molar extinction coefficient ε less than 10, which can be developed in an alkaline medium, with a resist thickness greater than 2 μιη and which is sensitive to radiation in the range of 340 to 390 nanometers. 7. A negative photoresist with a resist thickness greater than 2 µm that can be developed in an alkaline medium for an operating radiation of a wavelength between 340 and 390 nanometers, comprising an oximesulfonate of the formula la as described in claim 3, an alkali-soluble phenolic resin as a binder and a component which, upon acid catalysis, undergoes a cross-linking reaction with itself and / or with the binder. 8. Chemically enhanced positive photoresist, comprising a compound of the formula Ia, with a molar extinction coefficient ε less than 10, which can be developed in an alkaline medium, with a resist thickness greater than 2 μιη and which is sensitive to radiation in the range from 340 to 390 nanometers. A positive photoresist, comprising a compound of the formula Ia, as defined in claim 2, and a binder which is substantially insoluble in an alkaline developer and which becomes soluble in the developer in the presence of the photolysis products of the compound of the formula Ia . Use of a composition according to claim 1 for the preparation of negative, chemically enhanced photoresists, positive photoresists, printing plates, color filters or image recording materials. 30 A process for the production of negative chemically enhanced photoresists, positive photoresists, printing plates, color filters or image recording materials, wherein a 101 2 854% 4 composition according to claim 1 is irradiated with light of a wavelength of 340 to 390 nanometers. 12. An image production method comprising (a) coating a substrate with a composition according to claim 1, (b) irradiating the coating with radiation of a wavelength of 340 to 390 nanometers in a desired pattern , (c) heating the coating to temperatures of 60 to 160 ° C and (d) removing the soluble areas of the coating with an aqueous alkaline developer. 10 13. Use of a compound of the formula I or Ia, with a molar extinction coefficient ε less than 10, as a photo-suction generator in compositions comprising compounds which can be cross-linked by the action of an acid or / and as a solution inhibitor for compounds of which the solubility changes under the action of an acid. A method of generating sulfonic acids, wherein a photoacid generator of the formula Ia, having an extinction coefficient molar ratio ε less than 10, is irradiated with light of a wavelength in the range 340-390 nm. 20 A negative photoresist according to claim 7, comprising as the acid generating compound of the formula la a- (methanesulfoniumoxyimino) -3,4-dimethylphenylaceto-nitrile, a- (methanesulfoniumoxyimino) -4-methylphenylacetonitrile or a- (4-toluenesulfoniumoxyimino) phenylacetomtril. 1012854