Proposed is a novel chemical-sensitization resist composition capable of giving a positively or negatively patterned resist layer of excellent pattern resolution and cross sectional profile of the patterned resist layer with high sensitivity. Characteristically, the resist composition is formulated, as combined with a resinous ingredient which is subject to changes in the solubility behavior in an alkaline developer solution by interaction with an acid, with a specific oximesulfonate compound as the radiation-sensitive acid-generating agent represented by the general formula EQU R.sup.1 --C(CN).dbd.N--O--SO.sub.2 --R.sup.2, in which R.sup.1 is an inert organic group and R.sup.2 is an unsubstituted or substituted polycyclic monovalent hydrocarbon group selected from the group consisting of polycyclic aromatic hydrocarbon groups such as naphthyl and polycyclic non-aromatic hydrocarbon groups such as a terpene or camphor residue.

BACKGROUND OF THE INVENTION 
The present invention relates to a novel chemical-sensitization resist 
composition or, more particularly, to a chemical-sensitization resist 
composition, which may be positive-working or negative-working, capable of 
giving a patterned resist layer having an excellently orthogonal cross 
sectional profile with high sensitivity and high pattern resolution. 
It is a trend in recent years that the photolithographic patterning works 
in the manufacture of semiconductor devices, liquid crystal display panels 
and the like are conducted by using a chemical-sensitization resist 
composition. The working principle of the chemical-sensitization resist 
composition is that the solubility behavior of the resist layer in an 
alkaline developer solution is changed in the pattern-wise exposed areas 
by the catalytic activity of an acid generated from an acid-generating 
agent contained in the resist composition by the exposure to light. 
Chemical-sensitization resist compositions in general have an advantage of 
high sensitivity because good latent images can be formed even with a low 
exposure dose when the acid-generating agent has a high efficiency for 
radiation-induced generation of an acid. 
Chemical-sensitization resist compositions are classified into 
positive-working and negative-working compositions, each of which 
comprises an acid-generating agent capable of releasing an acid by 
irradiation with actinic rays and a film-forming resinous ingredient which 
is subject to a change in the solubility in an aqueous alkaline solution 
by the interaction with an acid. 
In the positive-working chemical-sensitization resist compositions, the 
film-forming resinous ingredient most widely under current use is a 
polyhydroxystyrene substituted for a part of the hydroxyl groups by 
acid-dissociable solubility-reducing groups such as tert-butoxycarbonyl 
groups, tetra-hydropyranyl groups and the like so as to be rendered 
insoluble in an aqueous alkaline solution. On the other hand, the 
negative-working chemical-sensitization resist compositions are 
formulated, as the film-forming resinous ingredient, with a combination of 
an alkali-soluble resin such as a novolak resin and polyhydroxystyrene 
resin optionally substituted for a part of the hydroxyl groups by the 
above mentioned solubility-reducing groups and an acid-crosslinkable 
compound such as melamine resins, urea resins and the like. 
It is known to employ an oximesulfonate compound as the acid-generating 
agent in a chemical-sensitization resist composition as is disclosed in 
Japanese Patent Kokai 1-124848, 2-154266, 2-161444 and 6-17433. The 
oximesulfonate compounds disclosed there include those having a cyano 
group in the molecule such as 
.alpha.-(p-toluenesulfonyloxyimino)phenyl acetonitrile, 
.alpha.-(p-chlorobenzenesulfonyloxyimino)phenyl acetonitrile, 
.alpha.-(4-nitrobenzenesulfonyloxyimino)phenyl acetonitrile, 
.alpha.-(4-nitro-2-trifluoromethylbenzenesulfonyloxyimino)phenyl 
acetonitrile, 
.alpha.-(benzenesulfonyloxyimino)-4-chlorophenyl acetonitrile, 
.alpha.-(benzenesulfonyloxyimino)-2,4-dichlorophenyl acetonitrile, 
.alpha.-(benzenesulfonyloxyimino)-2,6-dichlorophenyl acetonitrile, 
.alpha.-(benzenesulfonyloxyimino)-4-methoxyphenyl acetonitrile, 
.alpha.-(2-chlorobenzenesulfonyloxyimino)-4-methoxyphenyl acetonitrile, 
.alpha.-(benzenesulfonyloxyimino)-2-thienyl acetonitrile, 
.alpha.-(4-dodecylbenzenesulfonyloxyimino)phenyl acetonitrile, 
.alpha.-(4-toluenesulfonyloxyimino)-4-methoxyphenyl acetonitrile, 
.alpha.-(4-dodecylbenzenesulfonyloxyimino)-4-methoxyphenyl acetonitrile, 
.alpha.-(4-toluenesulfonyloxyimino)-3-thienyl acetonitrile, and the like. 
As is taught in Japanese Patent Kokai 2-154266, these oximesulfonate 
compounds having a cyano group in the molecule can release an acid by the 
energy of various kinds of actinic rays such as deep ultraviolet light, 
electron beams, ion beams, X-rays and the like and, when a 
positive-working chemical-sensitization resist composition comprising such 
an oximesulfonate compound and a film-forming resinous ingredient in 
combination is subjected to patterning by electron beam scanning, a 
patterned resist layer of about 0.35 .mu.m diameter in a hole pattern can 
be obtained. Also, a photocured patterned resist layer can be obtained 
from a negative-working chemical-sensitization resist composition 
comprising the oximesulfonate compound and a combination of a resin and an 
acid-crosslinkable compound by patterning with deep ultraviolet light. 
In the manufacturing process of semiconductor devices in recent years with 
a rapidly proceeding trend toward a higher and higher degree of 
integration requiring ultrafine photolithographic patterning works, the 
above mentioned resist compositions are no longer quite satisfactory in 
several respects. Accordingly, a further improved chemical-sensitization 
resist composition capable of giving a patterned resist layer of an 
excellent cross sectional profile with a further improved pattern 
resolution and still with a high sensitivity is eagerly desired. 
SUMMARY OF THE INVENTION 
The present invention accordingly has an object, in view of the above 
mentioned problems and disadvantages in the prior art resist compositions, 
to provide a novel and improved chemical-sensitization resist composition, 
which may be positive-working or negative-working, capable of giving a 
patterned resist layer of high pattern resolution having an excellently 
orthogonal cross sectional profile with high sensitivity. 
Thus, the chemical-sensitization resist composition provided by the present 
invention comprises, as a uniform solution in an organic solvent: 
(A) 100 parts by weight of a film-forming resinous ingredient subject to 
changes in the solubility in an aqueous alkaline solution by interacting 
with an acid; and 
(B1) from 0.5 to 20 parts by weight of an acid-generating agent capable of 
releasing an acid by exposure to actinic rays, which is an oximesulfonate 
compound having a cyano group in the molecule represented by the general 
formula 
EQU R.sup.1 --C(CN).dbd.N--O--SO.sub.2 --R.sup.2, (I) 
in which R.sup.1 is an inert organic group and R.sup.2 is an unsubstituted 
or substituted polycyclic monovalent hydrocarbon group including 
polycyclic aromatic hydrocarbon groups and polycyclic non-aromatic 
hydrocarbon groups, as an acid-generating agent. 
In a second aspect of the invention, the acid-generating agent as the 
component (B2) in the chemical-sensitization resist composition is a 
combination of the oximesulfonate compound of the general formula (I) 
defined above and an onium salt compound. 
In a third aspect of the invention, the acid-generating agent as the 
component (B3) in the chemical-sensitization resist composition is a 
combination of the oximesulfonate compound of the general formula (I) 
above and a second oximesulfonate compound having a cyano group in the 
molecule represented by the general formula 
EQU R.sup.3 --C(CN).dbd.N--O--SO.sub.2 --R.sup.4, (II) 
in which R.sup.3 is an unsubstituted or substituted monovalent hydrocarbon 
group selected from unsaturated or saturated non-aromatic hydrocarbon 
groups and aromatic cyclic hydrocarbon groups and R.sup.4 is an 
unsubstituted or substituted, unsaturated or saturated monovalent 
non-aromatic hydrocarbon group, or a third oximesulfonate compound having 
two or three cyano groups in the molecule represented by the general 
formula 
EQU A.brket open-st.C(CN).dbd.N--O--SO.sub.2 --R.sup.5 ].sub.n, (III) 
in which n is 2 or 3, R.sup.5 is an unsubstituted or substituted monovalent 
hydrocarbon group and A is a divalent or tervalent, when n is 2 or 3, 
respectively, organic group. 
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
As is described above, the most characteristic feature of the inventive 
resist composition consists in the use of one or more of very specific 
oximesulfonate compounds, optionally, in combination with an onium salt 
compound as the radiation-sensitive acid-generating agent. 
The component (A) as one of the essential ingredients in the 
chemical-sensitization resist composition of the present invention is a 
film-forming resinous material which is not particularly limitative. 
Namely, this component can be any one of those conventionally formulated 
in the positive-working or negative-working chemical-sensitization resist 
compositions of the prior art. 
When the inventive resist composition is positive-working, the component 
(A) is an alkali-soluble hydroxyl group-containing resin rendered 
alkali-insoluble by substitution of acid-dissociable protective groups for 
at least a part of the hydroxyl groups. When the inventive resist 
composition is negative-working, the component (A) is a combination of an 
alkali-soluble hydroxyl group-containing resin optionally substituted by 
acid-dissociable protective groups for a part of the hydroxyl groups and 
an acid-crosslinkable compound capable of being crosslinked by the 
interaction with an acid. 
When a layer of the positive-working chemical-sensitization resist 
composition of the invention comprising the above mentioned 
alkali-insolubilized resinous ingredient as the component (A) and the 
acid-generating agent as the component (B) is pattern-wise exposed to 
actinic rays, an acid is released from the acid-generating agent in the 
exposed areas so that the resinous ingredient in the exposed areas is 
rendered alkali-soluble as a consequence of dissociation of the 
acid-dissociable protective groups to regenerate the hydroxyl groups and 
selectively dissolved away in the development treatment with an aqueous 
alkaline developer solution to give a positively patterned resist layer. 
In the negative-working resist composition of the invention in which the 
resinous ingredient contains an acid-crosslinkable compound, the resist 
layer is insolubilized in the pattern-wise exposed areas due to the 
crosslinking reaction of the acid-crosslinkable compound by the 
interaction with the acid released from the acid-generating agent as the 
component (B) so that the resist layer in the unexposed areas is 
selectively dissolved away in the development treatment to give a 
negatively patterned resist layer. 
The above mentioned hydroxyl group-containing alkali-soluble resin is 
exemplified by novolak resins prepared by a condensation reaction of a 
phenolic compound such as phenol, m- and p-cresols, xylenols, trimethyl 
phenols and the like with an aldehyde compound such as formaldehyde and 
the like in the presence of an acid catalyst, hydroxystyrene-based 
polymers including homopolymers of a hydroxystyrene, copolymers of 
hydroxystyrene and other styrene monomers, copolymers of hydroxystyrene 
and an acrylic monomer such as (meth)acrylic acid and derivatives thereof, 
(meth)acrylic acid-based polymers including copolymers of (meth)acrylic 
acid and other comonomers copolymerizable therewith, and so on. 
The hydroxyl group-containing resin rendered alkali-insoluble by the 
substitution of acid-dissociable protective groups for the hydroxyl groups 
is exemplified by the hydroxystyrene-based polymers including homopolymers 
of a hydroxystyrene, copolymers of a hydroxystyrene and other styrene 
monomers, copolymers of a hydroxystyrene and an acrylic monomer such as 
(meth)acrylic acid and derivatives thereof and (meth)acrylic acid-based 
polymers including copolymers of (meth)acrylic acid and other comonomers 
copolymerizable therewith substituted by acid-dissociable protective 
groups for a part of the phenolic or carboxylic hydroxyl groups. 
The above mentioned styrene monomers copolymerizable with hydroxystyrene 
include styrene, .alpha.-methylstyrene, p- and o-methylstyrenes, 
p-methoxystyrene, p-chlorostyrene and the like. The derivatives of 
(meth)acrylic acid mentioned above include methyl (meth)acrylate, ethyl 
(meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl 
(meth)acrylate, (meth)acrylamide, (meth)acrylonitrile and the like. 
The acid-dissociable protective group mentioned above is exemplified by 
tert-alkoxycarbonyl groups such as tert-butoxycarbonyl group, 
tert-amyloxycarbonyl group, tert-alkyl groups such as tert-butyl group and 
the like, alkoxyalkyl groups such as ethoxyethyl group, methoxypropyl 
group and the like, acetal groups such as tetrahydropyranyl group, 
tetrahydrofuranyl group and the like, benzyl group, trimethylsilyl group 
and so on. 
It is preferable that from 1 to 60% or, more preferably, from 10 to 50% of 
the hydroxyl groups in the hydroxyl group-containing resin are protected 
by substitution of the above mentioned acid-dissociable groups. 
The positive-working chemical-sensitization resist composition as a class 
of the inventive compositions contains, preferably, as the component (A), 
a hydroxyl group-containing resin alkali-insolubilized by substitution of 
the acid-dissociable groups for the hydroxyl groups or, in particular, a 
polyhydroxystyrene resin substituted by tert-butoxycarbonyl groups or 
alkoxyalkyl groups, e.g., ethoxyethyl and methoxypropyl groups, for a part 
of the hydroxyl groups. In particular, the component (A) is a combination 
of a first polyhydroxystyrene resin substituted by tert-butoxycarbonyl 
groups for 10 to 50% or, preferably, 15 to 40% of the hydroxyl groups and 
a second polyhydroxystyrene resin substituted by alkoxyalkyl groups, e.g., 
ethoxyethyl or methoxypropyl groups, for 10 to 50% or, preferably, 15 to 
40% of the hydroxyl groups in a weight proportion of the first resin to 
the second resin in the range from 5:95 to 50:50 or, preferably, from 
10:90 to 30:70. 
The negative-working chemical sensitization resist compositions as the 
other class of the inventive compositions, on the other hand, contain, as 
the component (A), an alkali-soluble resin, e.g., novolak resins, 
hydroxystyrene-based polymers, (meth)acrylic acid-based polymers and the 
like, optionally, substituted by the acid-dissociable groups for a part of 
the hydroxyl groups, and an acid-crosslinkable compound in combination. In 
particular, the alkali-soluble resin is preferably a cresol novolak resin, 
polyhydroxystyrene resin or copolymer of hydroxystyrene and styrene, 
optionally, substituted by tert-butoxycarbonyl groups for a part of the 
hydroxyl groups. 
The acid-crosslinkable compound formulated in the negative-working 
chemical-sensitization resist composition of the invention can be selected 
without particular limitations from those conventionally used in the 
photoresist compositions of the same type in the prior art. Examples of 
suitable acid-crosslinkable compounds include amino resins having hydroxyl 
groups or alkoxy groups such as melamine resins, urea resins, guanamine 
resins, acetoguanamine resins, benzoguanamine resins, 
glycoluryl-formaldehyde resins, succinylamide-formaldehyde resins, 
ethyleneurea-formaldehyde resins and the like. These amino resins can be 
readily prepared by the methylolation reaction of melamine, urea, 
guanamine, acetoguanamine, benzoguanamine, glycoluryl, succinylamide, 
ethyleneurea and the like with formaldehyde in boiling water, optionally, 
followed by the alkoxylation reaction of the methylol groups with a lower 
alcohol. Various commercial resinous products of these types are available 
and can be used as such as the acid-crosslinkable compound in the present 
invention. Examples of such commercial products include Nikalacs Mx-750, 
Mw-30 and Mw-100LM as melamine resins and Nikalac Mx-290 as a urea resin 
(each a product by Sanwa Chemical Co.). Commercial products of 
benzoguanamine resins are also available with tradenames of Cymels 1123 
and 1128 (each a product by Mitsui Cyanamide Co.). 
Besides the above mentioned amino resins, benzene compounds having alkoxy 
groups such as 1,3,5-tris(methoxymethoxy) benzene, 
1,2,4-tris(isopropoxymethoxy) benzene and 1,4-bis(sec-butoxymethoxy) 
benzene and phenol compounds having hydroxyl or alkoxy groups such as 
2,6-dihydroxymethyl p-cresol and 2,6-dihydroxymethyl-p-tert-butyl phenol 
can also be used as the acid-crosslinkable compound in the inventive 
negative-working resist composition. 
The above described various acid-crosslinkable compounds can be used either 
singly or as a combination of two kinds or more according to need. 
The negative-working chemical-sensitization resist composition of the 
invention contains the above described alkali-soluble resin and 
acid-crosslinkable compound in combination in a weight proportion in the 
range from 100:3 to 100:70 or, preferably, from 100:5 to 100:50. When the 
amount of the acid-crosslinkable compound is too small, the resist 
composition is not imparted with sufficiently high sensitivity while, when 
the amount thereof is too large, a uniform resist layer can hardly be 
formed from the resist composition along with a decrease in the 
developability not to give a patterned resist layer of high quality. 
The alkali-soluble resin used as the component (A) in the inventive resist 
composition preferably has a weight-average molecular weight in the range 
from 2000 to 20000. The molecular weight distribution should preferably be 
as narrow as possible and the ratio of the weight-average molecular weight 
to number-average molecular weight M.sub.w :M.sub.n as a measure of the 
molecular weight distribution should not exceed 5.0 or, preferably, 3.0 
for novolak resins and should not exceed 5.0 or, preferably, 2.5 or, more 
preferably, 1.5 for hydroxystyrene-based resins. 
The chemical-sensitization resist composition of the invention is 
essentially contains, as the radiation-sensitive acid-generating agent, an 
oximesulfonate compound represented by the general formula 
EQU R.sup.1 --C(CN).dbd.N--O--SO.sub.2 --R.sup.2, (I) 
in which R.sup.1 is a monovalent inert organic group and R.sup.2 is an 
unsubstituted or substituted monovalent hydrocarbon group selected from 
the group consisting of aromatic polycyclic hydrocarbon groups and 
unsaturated or saturated non-aromatic polycyclic hydrocarbon groups. 
The above mentioned inert organic group denoted by R.sup.1 in the general 
formula (I) is a group having no reactivity with the various ingredients 
contained in the inventive resist composition. Though not particularly 
limitative, the group R.sup.1 is preferably an aromatic cyclic group in 
respect of the sensitivity to deep ultraviolet light, electron beams and 
X-rays. The aromatic cyclic group here implied is a group having physical 
and chemical properties inherent in aromatic compounds including, for 
example, phenyl, naphthyl, furyl and thienyl groups, optionally, 
substituted by inert substituent groups such as halogen atoms, e.g., atoms 
of chlorine, bromine and iodine, alkyl groups, alkoxy groups and nitro 
groups. 
The aromatic polycyclic hydrocarbon group as a class of the group denoted 
by R.sup.2 in the general formula (I) is exemplified by aromatic condensed 
polycyclic hydrocarbon groups such as 2-indenyl, 1-naphthyl, 2-naphthyl 
and 2-anthryl groups and aromatic non-condensed polycyclic hydrocarbon 
groups such as biphenyl and terphenyl groups. These hydrocarbon groups can 
be substituted by a substituent such as an atom of halogen, e.g., 
chlorine, bromine and iodine, nitro group, amino group, hydroxyl group, 
alkyl group and alkoxy group as in 5-hydroxy-1-naphthyl group and 
4-amino-1-naphthyl group. 
The unsaturated or saturated non-aromatic polycyclic hydrocarbon group as 
the other class of the groups denoted by R.sup.2 in the general formula 
(I) is preferably a polycyclic hydrocarbon group such as a polycyclic 
terpene residue and adamantyl group which can be substituted on the ring 
by an atom of halogen, e.g., chlorine, bromine and iodine, nitro group, 
amino group, hydroxyl group, oxo group, alkyl group or alkoxy group. 
Examples of the groups suitable as R.sup.2 include camphor-3-yl, 
camphor-8-yl, camphor-10-yl and 3-bromocamphor-10-yl groups. The group 
R.sup.2 is preferably a naphthyl group or camphor-10-yl group or, more 
preferably, 1-naphthyl group in respect of the good pattern resolution. 
The most characteristic feature of the present invention consists in the 
use of the above described very specific oximesulfonate compound as the 
acid-generating agent which imparts the chemical-sensitization resist 
composition with high sensitivity and high pattern resolution as well as 
excellent orthogonality of the cross sectional profile of the patterned 
resist layer. This feature is in great contrast with 
chemical-sensitization resist compositions formulated with a conventional 
oximesulfonate compound from which an acid such as p-toluenesulfonic acid 
or benzenesulfonic acid is generated. These sulfonic acids have a problem 
that the diffusion thereof in the post-exposure baking treatment of the 
resist layer is so large, in a positive-working resist layer, that the 
patterned hole in hole patterning has a larger diameter than the diameter 
in the mask pattern not to give desired pattern resolution. The advantage 
in the inventive resist composition in this regard is presumably due to 
the fact that the molecule of the acid released from the group R.sup.2 by 
exposure to deep ultraviolet light, electron beams, X-rays and the like is 
too bulky to cause rapid diffusion of the acid molecules in the 
post-exposure baking treatment consequently with an improvement in the 
pattern resolution. 
A problem in the prior art in this regard is that, when patterning is 
performed with ultraviolet light or deep ultraviolet light such as the 
i-line light of 365 nm wave-length and excimer laser beams, too large 
bulkiness of the acid molecules generated from the acid-generating agent 
results in insufficient diffusion of the acid molecules through the resist 
layer so that the adverse influence of the standing waves of the exposure 
light is increased so much and the patterned resist layer may have a wavy 
cross sectional profile. This is the reason for the attempts to use an 
acid-generating agent from which an acid having relatively small bulkiness 
of the molecule. In the present invention, in contrast thereto, high 
pattern resolution can be obtained in the pattern-wise exposure to 
electron beams and X-rays notwithstanding the bulkiness of the acid 
molecules generated from the oximesulfonate compound of the general 
formula (I). Furthermore, a patterned resist layer having excellent cross 
sectional profile can be obtained even by the exposure to deep ultraviolet 
light such as excimer laser beams from the resist composition of the 
invention containing the oximesulfonate compound of the general formula 
(I) in combination with the oximesulfonate compound of the general formula 
(II) or (III). This advantage is particularly remarkable when the 
inventive resist composition is negative-working. 
The oximesulfonate compound of the above given general formula (I) can be 
prepared by a known method. For example, a compound having an oxime group 
in the molecule and a compound having a sulfonyl chloride group in the 
molecule are subjected to an esterification reaction in an organic solvent 
such as tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide and 
N-methyl pyrrolidone in the presence of a basic catalyst such as pyridine, 
triethylamine and the like. The above mentioned oxime group-containing 
compound can be prepared by the methods described in literatures 
including: The Systematic Identification of Organic Compounds, page 181 
(John Wiley & Sons, 1980); Die Makromoleculare Chemie, volume 108, page 
170 (1967); Organic Syntheses, volume 59, page 95 (1979); and elsewhere. 
Examples of the oximesulfonate compounds represented by the general formula 
(I) and suitable as the component (B) in the inventive 
chemical-sensitization resist composition include: 
.alpha.-(1-naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide of the formula 
##STR1## 
.alpha.-(2-naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide of the 
formula 
##STR2## 
.alpha.-(10-camphorsulfonyloxyimino)-4-methoxybenzyl cyanide of the 
formula 
##STR3## 
.alpha.-(1-naphthylsulfonyloxyimino)benzyl cyanide of the formula 
##STR4## 
.alpha.-(2-naphthylsulfonyloxyimino)benzyl cyanide of the formula 
##STR5## 
.alpha.-(10-camphorsulfonyloxyimino)benzyl cyanide of the formula 
##STR6## 
and .alpha.-(3-camphorsulfonyloxyimino)-4-methoxybenzyl cyanide of the 
formula 
##STR7## 
The above described various oximesulfonate compounds represented by the 
general formula (I) can be used either singly or as a combination of two 
kinds or more according to need as the component (B) to serve as an 
acid-generating agent in the inventive resist composition. It is 
preferable that, when further improvement is desired in the sensitivity 
and pattern resolution of the inventive resist composition or, in 
particular, the positive-working resist composition of the invention, the 
acid-generating agent is a combination of the oximesulfonate compound of 
the general formula (I) and an onium salt compound. 
Examples of suitable onium salt compounds include: 
diphenyliodonium tetrafluoroborate; 
diphenyliodonium trifluoromethanesulfonate; 
diphenyliodonium hexafluoroantimonate; 
(4-methoxyphenyl)phenyliodonium hexafluoroantimonate; 
(4-methoxyphenyl)phenyliodonium trifluoromethanesulfonate; 
bis(p-tert-butylphenyl)iodonium trifluoromethanesulfonate; 
triphenylsulfonium trifluoromethanesulfonate; 
(4-methoxyphenyl)diphenylsulfonium hexafluoroantimonate; 
(4-methoxyphenyl)diphenylsulfonium trifluoromethanesulfonate; 
(4-methylphenyl)diphenylsulfonium trifluoromethanesulfonate; and 
(4-tert-butylphenyl)diphenylsulfonium trifluoromethanesulfonate. 
When the acid-generating agent is a combination of the oxime-sulfonate 
compound of the general formula (I) and an onium salt compound, the weight 
proportion of the onium salt compound preferably does not exceed 80% of 
the total amount of both. 
When the chemical-sensitization resist composition is intended for use as a 
positive-working resist composition to be pattern-wise exposed to deep 
ultraviolet light such as excimer laser beams, it is optional that the 
acid-generating agent further comprises a diazomethane compound which is 
exemplified by bissulfonyl diazomethane compounds such as 
bis(p-toluenesulfonyl) diazomethane, bis(1,1-dimethylethylsulfonyl) 
diazomethane, bis(cyclohexylsulfonyl) diazomethane, 
bis(2,4-dimethylphenylsulfonyl) diazomethane and the like. 
Further, the acid-generating agent in the inventive chemical-sensitization 
resist composition can be a combination of the oximesulfonate compound 
represented by the general formula (I) with a second oximesulfonate 
compound represented by the general formula 
EQU R.sup.3 --C(CN).dbd.N--O--SO.sub.2 R.sup.4, (II) 
in which R.sup.3 is an unsubstituted or substituted, unsaturated or 
saturated non-aromatic monovalent hydrocarbon group or aromatic monovalent 
cyclic group and R.sup.4 is an unsubstituted or substituted, unsaturated 
or saturated non-aromatic monovalent hydrocarbon group, and/or a third 
oximesulfonate compound represented by the general formula 
EQU A.brket open-st.C(CN).dbd.N--O--SO.sub.2 --R.sup.5 ].sub.n, (III) 
in which the subscript n is 2 or 3, each R.sup.5 is an unsubstituted or 
substituted monovalent hydrocarbon group and A is a divalent organic 
group, when the subscript n is 2, or a tervalent organic group, when the 
subscript n is 3. The inventive chemical-sensitization resist composition 
can be a negative-working resist composition suitable for pattern-wise 
exposure to deep ultraviolet light such as excimer laser beams when the 
acid-generating agent is a combination of the above mentioned two or three 
different oximesulfonate compounds. The divalent or tervalent organic 
group mentioned above is a residue of an organic compound from which two 
or three hydrogen atoms are removed to leave 2 or 3 free bonds available 
for the formation of chemical bonds. 
The above mentioned second oximesulfonate compound represented by the 
general formula (II) is selected preferably from those expressed by the 
general formula 
EQU R.sup.8 --C(CN).dbd.N--O--SO.sub.2 --R.sup.9, (V) 
in which each of R.sup.8 and R.sup.9 is a non-aromatic monovalent 
hydrocarbon group and those expressed by the general formula 
EQU R.sup.10 --C(CN).dbd.N--O--SO.sub.2 --R.sup.11, (VI) 
in which R.sup.10 is an aromatic monovalent cyclic group and R.sup.11 is an 
unsubstituted or halogen-substituted lower alkyl group. 
The above mentioned non-aromatic monovalent hydrocarbon group is 
exemplified by alkyl groups, halogenoalkyl groups, alkenyl groups, 
cycloalkyl groups, cycloalkenyl groups, alkoxy groups, cycloalkoxy groups 
and adamantyl group. The alkyl group is preferably a straightly linear or 
branched alkyl group having 1 to 12 carbon atoms such as methyl, ethyl, 
n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, 
n-octyl and n-dodecyl groups. The halogenoalkyl group includes 
monohalogenoalkyl groups and polyhalogenoalkyl groups without particular 
limitations. The halogen of the halogenoalkyl groups can be fluorine, 
chlorine, bromine or iodine. The halogenoalkyl group preferably has 1 to 4 
carbon atoms as exemplified by chloromethyl, trichloromethyl, 
trifluoromethyl and 2-bromopropyl groups. 
The alkenyl group mentioned above is preferably a straightly linear or 
branched alkenyl group having 2 to 6 carbon atoms exemplified by vinyl, 
1-propenyl, isopropenyl and 2-butenyl groups. The cycloalkyl group 
preferably has 5 to 12 carbon atoms as exemplified by cyclopentyl, 
cyclohexyl, cyclooctyl and cyclododecyl groups. The cycloalkenyl group 
preferably has 4 to 8 carbon atoms as exemplified by 1-cyclobutenyl, 
1-cyclopentenyl, 1-cyclohexenyl, 1-cycloheptenyl and 1-cyclooctenyl 
groups. The alkoxy group preferably has 1 to 8 carbon atoms as exemplified 
by methoxy, ethoxy, propoxy, butoxy and pentoxy groups. The cycloalkoxy 
group preferably has 5 to 8 carbon atoms as exemplified by cyclopentyloxy 
and cyclohexyloxy groups. 
The group denoted by R.sup.8 in the general formula (V) is preferably 
selected from the group consisting of alkyl groups, cycloalkyl groups and 
cycloalkenyl groups or, more preferably, from cycloalkenyl groups. The 
group denoted by R.sup.9 in the general formula (V) is preferably selected 
from the group consisting of straightly linear or branched alkyl groups 
having 1 to 4 carbon atoms, halogenoalkyl groups having 1 to 4 carbon 
atoms, alkoxy groups having 1 to 4 carbon atoms and alkenyl groups having 
2 to 4 carbon atoms. The number of the halogen atoms in the halogenoalkyl 
group is not particularly limitative and can be 1 or larger than 1. The 
halogen element of the halogenoalkyl group can be any of fluorine, 
chlorine, bromine and iodine. The group denoted by R.sup.9 is an alkyl 
group or halogenoalkyl group having 1 to 4 carbon atoms or, preferably, an 
alkyl group having 1 to 4 carbon atoms. More preferable is a compound of 
the general formula (V) in which R.sup.8 is a cycloalkenyl group and 
R.sup.9 is an alkyl group having 1 to 4 carbon atoms. 
Examples of the oximesulfonate compound expressed by the general formula 
(V) include: 
.alpha.-(methyl sulfonyloxyimino)-1-cyclopentenyl acetonitrile, 
.alpha.-(methyl sulfonyloxyimino)-1-cyclohexenyl acetonitrile, 
.alpha.-(methyl sulfonyloxyimino)-1-cycloheptenyl acetonitrile, 
.alpha.-(methyl sulfonyloxyimino)-1-cyclooctenyl acetonitrile, 
.alpha.-(trifluoromethyl sulfonyloxyimino)-1-cyclopentenyl acetonitrile, 
.alpha.-(trifluoromethyl sulfonyloxyimino)cyclohexyl acetonitrile, 
.alpha.-(ethyl sulfonyloxyimino)ethyl acetonitrile, 
.alpha.-(propyl sulfonyloxyimino)propyl acetonitrile, 
.alpha.-(ethyl sulfonyloxyimino)-1-cyclopentenyl acetonitrile, 
.alpha.-(isopropyl sulfonyloxyimino)-1-cyclopentenyl acetonitrile, 
.alpha.-(n-butyl sulfonyloxyimino)-1-cyclopentenyl acetonitrile, 
.alpha.-(ethyl sulfonyloxyimino)-1-cyclohexenyl acetonitrile, 
.alpha.-(isopropyl sulfonyloxyimino)-1-cyclohexenyl acetonitrile, 
.alpha.-(n-butyl sulfonyloxyimino)-1-cyclohexenyl acetonitrile and the 
like. 
In the above given general formula (VI), the aromatic cyclic group denoted 
by R.sup.10 includes phenyl, naphthyl, furyl and thienyl groups, which can 
be substituted by one or more of certain substituents such as halogen 
atoms, alkyl groups, alkoxy groups, nitro groups and the like. The alkyl 
group denoted by R.sup.11 is a straightly linear or branched alkyl group 
having 1 to 4 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, 
n-butyl, isobutyl, sec-butyl and tert-butyl groups. The halogenated lower 
alkyl group as a class of the groups denoted by R.sup.11 is a halogenated 
lower alkyl group having 1 to 4 carbon atoms such as chloromethyl, 
trichloromethyl, trifluoromethyl and 2-bromopropyl groups. 
Examples of the oximesulfonate compounds expressed by the above given 
general formula (VI) include: 
.alpha.-(methylsulfonyloxyimino)phenyl acetonitrile; 
.alpha.-(methylsulfonyloxyimino)-4-methoxyphenyl acetonitrile; 
.alpha.-(methylsulfonyloxyimino)-4-methylphenyl acetonitrile; 
.alpha.-(trifluoromethylsulfonyloxyimino)phenyl acetonitrile; 
.alpha.-(trifluoromethylsulfonyloxyimino)-4-methoxyphenyl acetonitrile; 
.alpha.-(ethylsulfonyloxyimino)-4-methoxyphenyl acetonitrile; 
.alpha.-(propylsulfonyloxyimino)-4-methylphenyl acetonitrile; 
.alpha.-(methylsulfonyloxyimino)-4-bromophenyl acetonitrile; and the like. 
The hydrocarbon group as a class of the groups denoted by R.sup.5 in the 
above given general formula (III) is exemplified preferably by straightly 
linear or branched alkyl groups having 1 to 4 carbon atoms and straightly 
linear or branched alkenyl groups having 2 to 4 carbon atoms. Examples of 
the alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, 
sec-butyl and tert-butyl groups and examples of the alkenyl groups include 
ethenyl, propenyl, butenyl and butadienyl groups. 
The hydrocarbon groups having a substituent group as a class of the groups 
denoted by R.sup.5 is exemplified by the alkyl and alkenyl groups named 
above substituted by substituents, such as atoms of halogen, e.g., 
chlorine, bromine and fluorine, hydroxyl groups, alkoxy groups and acyl 
groups, for at least one of the hydrogen atoms. The substituted 
hydrocarbon group denoted by R.sup.5 is preferably a halogenoalkyl group 
such as chloromethyl, trichloromethyl, trifluoromethyl and 2-bromopropyl 
groups. 
The divalent or tervalent organic group denoted by A in the general formula 
(III) is exemplified by divalent or tervalent aliphatic and aromatic 
hydrocarbon groups. 
Examples of the oximesulfonate compounds expressed by the above given 
general formula (III) include those compounds expressed by the following 
formulas, in which pPn is a 1,4-phenylene group, mPn is a 1,3-phenylene 
group, Me is a methyl group, Et is an ethyl group, Bu is a butyl group and 
FMe is a trifluoromethyl group: 
EQU Me--SO.sub.2 --O--N.dbd.C(CN)--pPn--C(CN).dbd.N--O--SO.sub.2 --Me; 
EQU Me--SO.sub.2 --O--N.dbd.C(CN)--mPn--C(CN).dbd.N--O--SO.sub.2 --Me; 
EQU Et--SO.sub.2 --O--N.dbd.C(CN)--pPn--C(CN).dbd.N--O--SO.sub.2 --Et; 
EQU Bu--SO.sub.2 --O--N.dbd.C(CN)--mPn--C(CN).dbd.N--O--SO.sub.2 --Bu; 
EQU Bu--SO.sub.2 --O--N.dbd.C(CN)--pPn--C(CN).dbd.N--O--SO.sub.2 --Bu; 
EQU FMe--SO.sub.2 --O--N.dbd.C(CN)--pPn--C(CN).dbd.N--O--SO.sub.2 --FMe; and 
EQU FMe--SO.sub.2 --O--N.dbd.C(CN)--mPn--C(CN).dbd.N--O--SO.sub.2 --FMe. 
The oximesulfonate compounds represented by the general formulas (II) and 
(III) can be used either singly or as a combination of two kinds or more 
according to need. 
The oximesulfonate compound represented by the general formula (I), when 
irradiated by actinic rays, releases an acid of high bulkiness of 
molecules so that, when such an oximesulfonate compound is used singly as 
the acid-generating agent in a negative-working resist composition for 
deep ultraviolet light, diffusion of the acid molecules released therefrom 
through the resist layer is not rapid enough during the post-exposure 
baking treatment so that the cross sectional profile of the patterned 
resist layer has a wavy sideline and is trapezoidal narrowing upwardly. 
When the oximesulfonate compound as the acid generating agent is a 
compound represented by the general formula (II) or (III), on the other 
hand, the acid released therefrom by the irradiation with actinic rays has 
less bulkiness of the molecules rapidly diffusing in the post-exposure 
baking treatment so that the cross sectional profile of the patterned 
resist layer is inversely trapezoidal broadening upwardly but without 
waviness on the sidelines. Accordingly, a preferable formulation of the 
inventive resist composition is to formulate the oximesulfonate compound 
of the general formula (I) and the oximesulfonate compound of the general 
formula (II) or (III) in combination in an appropriate proportion so that 
a patterned resist layer having an excellent cross sectional profile can 
be obtained. 
Though not particularly limitative, the weight proportion of the above 
mentioned two classes of the oximesulfonate compounds formulated in 
combination is in the range from 2:8 to 8:2 or, preferably, from 4:6 to 
6:4 in order that the characteristic features of the two classes of the 
compounds can be exhibited respectively. It is preferable in order to 
facilitate adequate setting of the sensitivity of the resist composition 
formulated with the two classes of the oximesulfonate compounds in 
combination that the two oximesulfonate compounds have light absorption 
characteristics, e.g., wavelength range of the ultraviolet absorption band 
and light absorption coefficient, close each to the other. Examples of 
preferable combinations of the two classes of the oximesulfonate compounds 
include a combination of 
.alpha.-(1-naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide as the 
compound of the general formula (I) and 
.alpha.-(methylsulfonyloxyimino)-1-benzyl cyanide as the compound of the 
general formula (II) or (III) and a combination of 
.alpha.-(10-camphorsulfonyloxyimino)-4-methoxybenzyl cyanide as the 
compound of the general formula (I) and 
.alpha.-(methylsulfonyloxyimino)-4-methylbenzyl cyanide as the compound of 
the general formula (II) or (III). 
It is optional in the formulation of the inventive resist composition that 
the oximesulfonate compound of the general formula (I) and/or the 
oximesulfonate compound of the general formula (II) or (III) are combined 
with one or more of other oximesulfonate compounds according to need. Such 
an optional oximesulfonate compound is exemplified by those represented by 
the above given general formula (V) in which the non-aromatic hydrocarbon 
group denoted by R.sup.9 is an alkyl group, halogenoalkyl group, alkenyl 
group, cycloalkyl group, cycloalkenyl group, alkoxy group or cycloalkoxy 
group having 5 to 12 carbon atoms. Particular examples of such groups 
include n-pentyl, n-octyl, n-dodecyl, hexenyl, cyclopentyl, cyclohexyl, 
cyclooctyl, cyclododecyl, 1-cyclopentenyl, 1-cyclohexenyl, 
1-cycloheptenyl, 1-cyclooctenyl, pentoxy, cyclopentyloxy and cyclohexyloxy 
groups. 
Particular examples of such oximesulfonate compounds include 
.alpha.-(cyclohexylsulfonyloxyimino) cyclopentyl acetonitrile, 
.alpha.-(cyclohexylsulfonyloxyimino) cyclohexyl acetonitrile and 
.alpha.-(cyclohexylsulfonyloxyimino) 1-cyclopentenyl acetonitrile. 
It is further optional to use an oximesulfonate compound represented by the 
above given general formula (III) in which the unsubstituted or 
substituted hydrocarbon group denoted by R.sup.5 is selected from aromatic 
cyclic groups and alkyl, alkenyl, cycloalkyl and cycloalkenyl groups 
having 5 to 12 carbon atoms as well as those substituted groups obtained 
by replacing one or more of the hydrogen atoms in the above named 
hydrocarbon groups with halogen atoms, hydroxyl groups, alkoxy groups or 
acyl groups. The above mentioned aromatic cyclic group preferably has 6 to 
14 carbon atoms including aromatic hydrocarbon groups such as phenyl, 
tolyl, methoxyphenyl, xylyl, biphenyl, naphthyl and anthryl groups and 
heterocyclic groups such as furanyl, pyridyl and quinolyl groups. Examples 
of the alkyl, alkenyl, cycloalkyl and cycloalkenyl groups having 5 to 12 
carbon atoms include n-pentyl, n-octyl, n-dodecyl, hexenyl, octadienyl, 
cyclopentyl, cyclohexyl, cyclooctyl, cyclododecyl, 1-cyclopentenyl, 
1-cyclohexenyl, 1-cycloheptenyl and 1-cyclooctenyl groups. 
Particular examples of such oximesulfonate compounds include those 
expressed by the following formulas, in which pPn is a 1,4-phenylene 
group, mPn is a 1,3-phenylene group, Me is a methyl group, Ch is a 
cyclohexyl group and Ph is a phenyl group: 
EQU Ch--SO.sub.2 --O--N.dbd.C(CN)--pPn--C(CN).dbd.N--O--SO.sub.2 --Ch; 
EQU Ph--SO.sub.2 --O--N.dbd.C(CN)--pPn--C(CN).dbd.N--O--SO.sub.2 --Ph; 
EQU Me--pPn--SO.sub.2 --O--N.dbd.C(CN)--pPn--C(CN).dbd.N--O--SO.sub.2 
--pPn--Me; 
EQU Me--pPn--SO.sub.2 --O--N.dbd.C(CN)--mPn--C(CN).dbd.N--O--SO.sub.2 
--pPn--Me; and 
EQU MeO--pPn--SO.sub.2 --O--N.dbd.C(CN)--mPn--C(CN).dbd.N--O--SO.sub.2 
--pPn--OMe. 
As to the proportion of compounding of the respective components in the 
inventive resist composition, it is advantageous that the acid-generating 
agent is used in an amount in the range from 0.5 to 20 parts by weight or, 
preferably, from 1.0 to 10.0 parts by weight as the oximesulfonate 
compound per 100 parts by weight of the film-forming constituent as the 
component (A) in consideration of the balance of the properties such as 
image formation, formation of a resist film and developability. When the 
amount of the acid-generating agent is too small, full image formation 
cannot be accomplished while, when the amount thereof is too large, a good 
resist film can hardly be formed from the composition along with a 
decrease in the developability not to give an excellently patterned resist 
layer. 
It is optional that the resist composition of the invention is admixed, in 
order to improve the stability of the latent image formed in the resist 
layer after pattern-wise exposure to actinic rays before a post-exposure 
baking treatment, with an amine compound including aliphatic amines such 
as trimethylamine, ethylamine, diethylamine, triethylamine, n-propylamine, 
di-n-propylamine and tri-n-propylamine, aromatic amines such as 
benzylamine, aniline, N-methylaniline and N,N-dimethylaniline and 
heterocyclic amines such as pyridine, 2-methylpyridine, 2-ethylpyridine 
and 2,3-dimethylpyridine, of which triethylamine is particularly 
preferable because this amine compound gives a resist composition of which 
the cross sectional profile of the patterned resist layer is excellently 
orthogonal along with good stability of the latent images formed in the 
resist layer by pattern-wise exposure to actinic rays. 
Further, it is optional according to need that the inventive resist 
composition is admixed with a carboxylic acid including saturated or 
unsaturated aliphatic carboxylic acids such as butyric acid, isobutyric 
acid, oxalic acid, malonic acid, succinic acid, acrylic acid, crotonic 
acid, isocrotonic acid, 3-butenoic acid, methacrylic acid and 4-pentenoic 
acid, alicyclic carboxylic acid such as 1,1-cyclohexane dicarboxylic acid, 
1,2-cyclohexane dicarboxylic acid, 1,3-cyclohexane dicarboxylic acid, 
1,4-cyclohexane dicarboxylic acid and 1,1-cyclohexyl diacetic acid and 
aromatic carboxylic acids having a hydroxyl, nitro, carboxyl or vinyl 
groups as the substituent such as p-hydroxybenzoic acid, o-hydroxybenzoic 
acid, 2-hydroxy-3-nitrobenzoic acid, 3,5-dinitrobenzoic acid, 
2-nitrobenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 
2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic 
acid, 2-vinylbenzoic acid, 4-vinylbenzoic acid, phthalic acid, 
terephthalic acid and isophthalic acid. 
Among the above named carboxylic acids, aromatic carboxylic acids are 
preferred in respect of the adequate strength of the acid. In particular, 
salicylic acid is more preferable because this acid has good solubility in 
the solvents used in resist compositions along with excellent patterning 
behavior of the resist composition formulated therewith. 
As to the amounts of addition of these amine compounds and carboxylic acid 
compounds, the amount of the amine compound is in the range from 0.01 to 
1% by weight or, preferably, from 0.05 to 0.5% by weight and the amount of 
the carboxylic acid compound is in the range from 0.01 to 10% y weight or, 
preferably, from 0.05 to 2.0% by weight each based on the amount of the 
component (A). 
It is usually preferable that the resist composition of the invention is in 
the form of a solution prepared by dissolving the above described 
ingredients in a suitable organic solvent. Examples of suitable organic 
solvents include ketone solvents such as acetone, methyl ethyl ketone, 
cyclohexanone, methyl isoamyl ketone and 2-heptanone, polyhydric alcohols 
and derivatives thereof such as ethyleneglycol, ethyleneglycol 
monoacetate, diethyleneglycol, diethyleneglycol monoacetate, 
propyleneglycol, propyleneglycol monoacetate, dipropyleneglycol and 
dipropyleneglycol monoacetate as well as monomethyl, monoethyl, 
monopropyl, monobutyl and monophenyl ethers thereof, cyclic ether solvents 
such as dioxane, ester solvents such as methyl lactate, ethyl lactate, 
methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl 
pyruvate, methyl methoxypropionate and ethyl ethoxypropionate, and amide 
solvents such as N,N-dimethylformamide, N,N-dimethylacetamide and 
N-methyl-2-pyrrolidone. These organic solvents can be used either singly 
or as a mixture of two kinds or more according to need. 
It is of course optional according to need that the resist composition of 
the present invention is admixed with various kinds of known additives 
conventionally used in resist compositions such as auxiliary resins to 
modify the film properties, plasticizers, stabilizers, coloring agents, 
surface active agents and the like each in a limited amount. 
The procedure for photolithographic patterning by using the inventive 
resist composition can be conventional as in the use of prior art resist 
compositions. Namely, a substrate such as a semiconductor silicon wafer is 
coated uniformly with the resist composition by using a suitable coating 
machine such as spinners followed by drying to form a dried resist layer 
which is pattern-wise exposed to actinic rays such as deep ultraviolet 
light, X-rays, electron beams and the like followed by a post-exposure 
baking treatment. Thereafter, the resist layer is subjected to a 
development treatment with an aqueous alkaline developer solution which is 
typically a 1 to 10% by weight aqueous solution of tetramethylammonium 
hydroxide so as to dissolve away the resist layer pattern-wise. The thus 
obtained patterned resist layer is excellent in pattern resolution and has 
an orthogonal cross sectional profile. 
The present invention also provides a class of novel radiation-sensitive 
acid-generating compounds useful as an ingredient in a 
chemical-sensitization resist composition. The novel compound is an 
oximesulfonate compounds represented by the general formula 
EQU R.sup.6 --C(CN).dbd.N--O--SO.sub.2 --R.sup.7, (IV) 
in which R.sup.6 is an aromatic cyclic group and R.sup.7 is a naphthyl 
group or a camphor residue. The aromatic cyclic group denoted by R.sup.6 
in the general formula (IV) is exemplified by the same groups given as the 
examples of the aromatic cyclic group denoted by R.sup.1 in the general 
formula (I). 
By virtue of the bulkiness of the acid molecules derived from the group 
R.sup.7 in the oximesulfonate compound of the general formula (IV) and 
released in the resist layer, i.e. naphthalenesulfonic acid or 
camphorsulfonic acid, by the exposure of the resist layer to actinic rays, 
the inventive chemical-sensitization resist composition containing the 
oximesulfonate compound as an acid generating agent has an advantage of 
high pattern resolution. 
In the following, the chemical-sensitization resist composition of the 
present invention is illustrated in more detail by way of Examples, which, 
however, never limit the scope of the invention in any way, as preceded by 
a description of the synthetic procedure for several oximesulfonate 
compounds used in the formulation of the resist compositions. 
Preparation 1. 
.alpha.-(1-Naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide expressed by 
the structural formula 
##STR8## 
was synthesized in the following manner. 
Thus, 51.0 g (0.29 mole) of .alpha.-hydroxyimino-4-methoxybenzyl cyanide 
and 44.0 g (0.43 mole) of triethylamine were dissolved in 400 ml of 
tetrahydrofuran in a reaction vessel and the solution was chilled to and 
kept at -5.degree. C. Thereafter, 72.3 g (0.32 mole) of 
1-nahthalenesulfonyl chloride were added to the solution dropwise over 2 
hours and the reaction mixture was agitated for further 3 hours at 
-5.degree. C. and then for 2 hours at about 10.degree. C. In the next 
place, the reaction mixture was freed from tetrahydrofuran by distillation 
under reduced pressure at 30.degree. C. to give 101.1 g of a solid 
product, which was purified by repeating recrystallization from 
acetonitrile to give 74.5 g of a white crystalline product melting at 
121.degree. C. Assuming that this product was the desired oximesulfonate 
compound mentioned above, the yield of the product corresponds to 70% of 
the theoretical value. 
The infrared absorption spectrum of the above obtained product compound had 
absorption bands with peaks at wave numbers of 711 cm.sup.-1, 838 
cm.sup.-1, 1186 cm.sup.-1, 1606 cm.sup.-1 and 2237 cm.sup.-1. The proton 
NMR absorption spectrum (.sup.1 H-NMR, solvent: acetone-d.sub.6) had peaks 
at .delta. of 3.80 ppm, 6.91 ppm, 7.54 ppm, 7.60 to 7.87 ppm, 8.05 ppm, 
8.37 ppm, 8.50 ppm and 8.72 ppm. Further, the ultraviolet absorption 
spectrum of the compound in propyleneglycol monomethyl ether as the 
solvent had absorption bands at .lambda..sub.max =229 nm with 
.epsilon.=31700 and .lambda..sub.max =321 nm with .epsilon.=15600. 
Preparation 2. 
.alpha.-(2-Naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide expressed by 
the structural formula 
##STR9## 
was synthesized in substantially the same manner as in Preparation 1 
described above excepting for the replacement of 72.3 g (0.32 mole) of 
1-nahthalenesulfonyl chloride with the same amount of 2-nahthalenesulfonyl 
chloride to give 69.1 g of a white crystalline product melting at 
108.degree. C. Assuming that this product was the desired oximesulfonate 
compound mentioned above, the yield of the product corresponds to 65% of 
the theoretical value. 
The infrared absorption spectrum of the above obtained product compound had 
absorption bands with peaks at wave numbers of 709 cm.sup.-1, 860 
cm.sup.-1, 1186 cm.sup.-1, 1606 cm.sup.-1 and 2237 cm.sup.-1. The proton 
NMR absorption spectrum (.sup.1 H-NMR, solvent: acetone-d.sub.6) had peaks 
at .delta. of 3.85 ppm, 6.99 ppm, 7.69 to 8.27 ppm, and 8.80 ppm. Further, 
the ultraviolet absorption spectrum of the compound in propyleneglycol 
monomethyl ether as the solvent had absorption bands at .lambda..sub.max 
=231 nm with .epsilon.=57600 and .lambda..sub.max =326 nm with 
.epsilon.=14000. 
Preparation 3. 
.alpha.-(10-Camphorsulfonyloxyimino)-4-methoxybenzyl cyanide expressed by 
the structural formula 
##STR10## 
was synthesized in substantially the same manner as in Preparation 1 
described above excepting for the replacement of 72.3 g (0.32 mole) of 
1-naphthalenesulfonyl chloride with 84.5 g (0.32 mole) of 
(+)10-camphorsulfonyl chloride to give 58.7 g of a white crystalline 
product melting at 130.degree. C. Assuming that this product was the 
desired oximesulfonate compound mentioned above, the yield of the product 
corresponds to 50.0% of the theoretical value. 
The infrared absorption spectrum of the above obtained product compound had 
absorption bands with peaks at wave numbers of 838 cm.sup.-1, 1180 
cm.sup.-1, 1265 cm.sup.-1, 1606 cm.sup.-1 and 1749 cm.sup.-1. The proton 
NMR absorption spectrum (.sup.1 H-NMR, solvent: acetone-d.sub.6) had peaks 
at .delta. of 0.90 ppm, 1.15 ppm, 1.40 to 2.60 ppm, 3.90 ppm, 7.00 ppm and 
7.85 ppm. Further, the ultraviolet absorption spectrum of the compound in 
propyleneglycol monomethyl ether as the solvent had absorption bands at 
.lambda..sub.max =229 nm with .epsilon.=8300 and .lambda..sub.max =324 nm 
with .epsilon.=13500. 
Preparation 4. 
.alpha.-(3-Bromo-10-camphorsulfonyloxyimino)-4-methoxybenzyl cyanide 
expressed by the structural formula 
##STR11## 
was synthesized in the following manner. 
The synthetic procedure was substantially the same as in Preparation 1 
excepting for the increase of the amount of 
.alpha.-hydroxyimino-4-methoxybenzyl cyanide from 51.0 g to 63.3 g (0.36 
mole) and replacement of 72.3 g (0.32 mole) of 1-naphthalenesulfonyl 
chloride with 141.5 g (0.43 mole) of 3-bromo-10-camphorsulfonyl chloride 
to obtain 101.5 g of a white crystalline product melting at 121.degree. C 
. Assuming that this product is the above mentioned target compound, this 
yield corresponds to 60.0% of the theoretical value. 
The infrared absorption spectrum of the above obtained product compound had 
absorption bands with peaks at wave numbers of 838 cm.sup.-1, 1180 
cm.sup.-1, 1265 cm.sup.-1, 1606 cm.sup.-1 and 1749 cm.sup.-1. The proton 
NMR absorption spectrum (.sup.1 H-NMR, solvent: acetone-d.sub.6) had peaks 
at .delta. of 0.90 ppm, 1.15 ppm, 1.40 to 2.60 ppm, 3.90 ppm, 7.00 ppm and 
7.85 ppm. Further, the ultraviolet absorption spectrum of the compound in 
propyleneglycol monomethyl ether as the solvent had absorption bands at 
.lambda..sub.max =229 nm with .epsilon.=8300 and .lambda..sub.max =324 nm 
with .epsilon.=13500. 
Preparation 5. 
.alpha.-(3-Bromo-10-camphorsulfonyloxyimino)-4-bromobenzyl cyanide 
expressed by the structural formula 
##STR12## 
was synthesized in the following manner. 
The synthetic procedure was substantially the same as in Preparation 1 
excepting for the replacement of .alpha.-hydroxyimino-4-methoxybenzyl 
cyanide with 81.0 g (0.36 mole) of .alpha.-hydroxyimino-4-bromobenzyl 
cyanide and replacement of 72.3 g (0.32 mole) of 1-naphthalenesulfonyl 
chloride with 141.5 g (0.43 mole) of 3-bromo-10-camphorsulfonyl chloride 
to obtain 100.8 g of a white crystalline product melting at 115.degree. C 
. Assuming that this product is the above mentioned target compound, this 
yield corresponds to 54.0% of the theoretical value. 
The infrared absorption spectrum of the above obtained product compound had 
absorption bands with peaks at wave numbers of 838 cm.sup.-1, 1180 
cm.sup.-1, 1265 cm.sup.-1, 1606 cm.sup.-1 and 1749 cm.sup.-1. The proton 
NMR absorption spectrum (.sup.1 H-NMR, solvent: acetone-d.sub.6) had peaks 
at .delta. of 0.90 ppm, 1.15 ppm, 1.40 to 2.60 ppm, 7.80 ppm and 7.88 ppm. 
Further, the ultraviolet absorption spectrum of the compound in 
propyleneglycol monomethyl ether as the solvent had absorption bands at 
.lambda..sub.max =226 nm with .epsilon.=3000 and .lambda..sub.max =292 nm 
with .epsilon.=11000.

EXAMPLE 1 
A chemical-sensitization positive-working resist composition was prepared 
by dissolving, in 400 parts by weight of propyleneglycol monomethyl ether 
acetate, 25 parts by weight of a first polyhydroxystyrene resin having a 
weight-average molecular weight of 12000 with a molecular weight 
distribution M.sub.w :M.sub.n of 4.6, which was substituted by 
tert-butyloxycarbonyl groups for 39% of the hydroxyl groups, 75 parts by 
weight of a second polyhydroxystyrene resin having a weight-average 
molecular weight of 12000 with a molecular weight distribution M.sub.w 
:M.sub.n of 4.6, which was substituted by ethoxyethyl groups for 39% of 
the hydroxyl groups, 3 parts by weight of the oximesulfonate compound 
prepared in Preparation 1 described above, i.e. 
.alpha.-(1-naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide, as the 
acid-generating agent, 0.06 part by weight of triethylamine and 0.06 part 
by weight of salicylic acid followed by filtration of the solution through 
a membrane filter of 0.2 .mu.m pore diameter. 
A semiconductor silicon wafer was coated on a spinner with the thus 
prepared positive-working resist solution followed by drying on a hot 
plate at 100.degree. C. for 90 seconds to give a dried resist layer having 
a thickness of 1.5 .mu.m. This resist layer was pattern-wise irradiated 
with electron beams on an electron beam exposure machine (Model HL-750D, 
manufactured by Hitachi Ltd.) immediately followed by a post-exposure 
baking treatment at 120.degree. C. for 90 seconds and then by a 
development treatment in a 2.38% by weight aqueous solution of 
tetramethylammonium hydroxide at 23.degree. C. for 65 seconds followed by 
rinse with water for 30 seconds and drying. By conducting the electron 
beam exposure with different exposure doses, the minimum dose in 
.mu.C/cm.sup.2 was recorded as a measure of the sensitivity by which the 
resist layer was completely dissolved away in the development treatment on 
the exposed areas. The sensitivity in this case was 7.0 .mu.C/cm.sup.2. 
The pattern resolution in the hole-patterned resist layer was 0.30 .mu.m. 
The cross sectional profile of the patterned resist layer as examined on a 
scanning electron microscopic photograph was excellently orthogonal 
standing upright on the substrate surface. 
EXAMPLE 2 
A second chemical-sensitization positive-working resist composition was 
prepared in the same formulation as in the resist composition in Example 1 
excepting for the replacement of the acid-generating agent with 3 parts by 
weight of .alpha.-(2-naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide 
prepared in Preparation 2. 
Evaluation of the thus prepared resist composition was undertaken in the 
same manner as in Example 1 to find that the sensitivity and pattern 
resolution thereof were 7.0 .mu.C/cm.sup.2 and 0.30 .mu.m, respectively. 
The cross sectional profile of the hole-patterned resist layer as examined 
on a scanning electron microscopic photograph was also excellently 
orthogonal standing upright on the substrate surface. 
EXAMPLE 3 
A third chemical-sensitization positive-working resist composition was 
prepared in the same formulation as in the resist composition in Example 1 
excepting for the replacement of the acid-generating agent with 3 parts by 
weight of .alpha.-(10-camphorsulfonyloxyimino)-4-methoxybenzyl cyanide 
prepared in Preparation 3. 
Evaluation of the thus prepared resist composition was undertaken in the 
same manner as in Example 1 to find that the sensitivity and pattern 
resolution thereof were 9.0 .mu.C/cm.sup.2 and 0.30 .mu.m, respectively. 
The cross sectional profile of the hole-patterned resist layer as examined 
on a scanning electron microscopic photograph was also excellently 
orthogonal standing upright on the substrate surface. 
EXAMPLE 4 
The experimental procedure was just the same as in Example 1 except that 
the resist layer was pattern-wise exposed to X-rays instead of the 
pattern-wise scanning with electron beams. The sensitivity and pattern 
resolution of the resist composition were 80 mJ/cm.sup.2 and 0.25 .mu.m, 
respectively. The cross sectional profile of the hole-patterned resist 
layer as examined on a scanning electron microscopic photograph was also 
excellently orthogonal standing upright on the substrate surface. 
COMATIVE EXAMPLE 
A comparative chemical-sensitization positive-working resist composition 
was prepared in the same formulation as in the resist composition in 
Example 1 excepting for the replacement of the acid-generating agent with 
3 parts by weight of .alpha.-(benzenesulfonyloxyimino)-4-methoxybenzyl 
cyanide. 
Evaluation of the thus prepared comparative resist composition was 
undertaken in the same manner as in Example 1 to find that the sensitivity 
and pattern resolution thereof were 10.0 .mu.C/cm.sup.2 and 0.36 .mu.m, 
respectively. The cross sectional profile of the hole-patterned resist 
layer as examined on a scanning electron microscopic photograph was not 
orthogonal but trapezoidal narrowing upwardly. 
EXAMPLE 5. 
A chemical-sensitization positive-working resist composition was prepared 
by dissolving, in 400 parts by weight of propyleneglycol monomethyl ether 
acetate, 10 parts by weight of a first polyhydroxystyrene resin having a 
weight-average molecular weight of 12000 with a molecular weight 
distribution expressed by M.sub.w :M.sub.n of 4.6, which was substituted 
by tert-butyloxycarbonyl groups for 28% of the hydroxyl groups, 90 parts 
by weight of a second polyhydroxystyrene resin having a weight-average 
molecular weight of 12000 with a molecular weight distribution expressed 
by M.sub.w :M.sub.n of 4.6, which was substituted by ethoxyethyl groups 
for 28% of the hydroxyl groups, 3 parts by weight of 
.alpha.-(1-naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide prepared in 
Preparation 1 described above, 5 parts by weight of 
bis(p-tert-butylphenyl)iodonium trifluoromethane sulfonate, 0.06 part by 
weight of triethylamine and 0.06 part by weight of salicylic acid followed 
by filtration of the solution through a membrane filter having a pore 
diameter of 0.2 .mu.m. 
A semiconductor silicon wafer was coated on a spinner with the thus 
prepared positive-working resist solution followed by drying on a hot 
plate at 90.degree. C. for 90 seconds to give a dried resist layer having 
a thickness of 0.7 .mu.m. This resist layer was pattern-wise irradiated 
with electron beams on an electron beam exposure machine (Model HL-750D, 
manufactured by Hitachi Ltd.) immediately followed by a post-exposure 
baking treatment at 110.degree. C. for 90 seconds and then by a 
development treatment in a 2.38% by weight aqueous solution of 
tetramethylammonium hydroxide at 23.degree. C. for 65 seconds followed by 
rinse with water for 30 seconds and drying. By conducting the electron 
beam exposure with different exposure doses, the minimum dose in 
.mu.C/cm.sup.2 was recorded as a measure of the sensitivity by which the 
resist layer was completely dissolved away in the development treatment on 
the exposed areas. The sensitivity in this case was 7.0 .mu.C/cm.sup.2. 
The pattern resolution in the hole-patterned resist layer was 0.14 .mu.m. 
The cross sectional profile of the patterned resist layer as examined on a 
scanning electron microscopic photograph was excellently orthogonal 
standing upright on the substrate surface. 
EXAMPLE 6 
The experimental procedure was substantially the same as in Example 5 
except that the resist layer on the substrate surface was pattern-wise 
exposed to X-rays instead of pattern-wise irradiation by electron beam 
scanning. The sensitivity in this case was 70 mJ/cm.sup.2 and the pattern 
resolution was 0.15 .mu.m. The cross sectional profile of the patterned 
resist layer as examined on a scanning electron microscopic photograph was 
excellently orthogonal standing upright on the substrate surface. 
EXAMPLE 7 
A chemical-sensitization negative-working resist composition was prepared 
by dissolving, in 585 parts by weight of propyleneglycol monomethyl ether 
acetate, 100 parts by weight of a copolymeric resin of p-hydroxystyrene 
and styrene in a molar ratio of 85:15 having a weight-average molecular 
weight of 2500 with a molecular weight distribution expressed by M.sub.w 
:M.sub.n of 1.23 and 10 parts by weight of a melamine resin (Nikalac 
Mw-30, a product by Sanwa Chemical Co.) to give a solution which was 
admixed with 4 parts by weight of 
.alpha.-(1-naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide prepared in 
Preparation 1 described above and 2 parts by weight of 
.alpha.-(methylsulfonyloxyimino)-1-benzyl cyanide and then with 2 parts by 
weight of 2,2',4,4'-tetrahydroxy benzophenone. 
A semiconductor silicon wafer was coated on a spinner with the thus 
prepared negative-working resist solution followed by drying on a hot 
plate at 100.degree. C. for 90 seconds to give a dried resist layer having 
a thickness of 0.73 .mu.m. This resist layer was pattern-wise exposed to 
excimer laser beams on the minifying projection exposure machine (Model 
NSR-2005EX8A, manufactured by Nikon Co.) followed by a post-exposure 
baking treatment at 120.degree. C. for 90 seconds and then the resist 
layer was subjected to a development treatment in a 2.38% by weight 
aqueous solution of tetramethylammonium hydroxide at 23.degree. C. for 65 
seconds followed by rinse with water for 30 seconds and drying. By 
conducting the excimer laser beam exposure with different exposure doses, 
the minimum dose, by which a line-and-space resist pattern of 0.35 .mu.m 
line width could be formed in a 1:1 line to space ratio, in mJ/cm.sup.2 
was recorded as a measure of the sensitivity. The sensitivity in this case 
was 38 mJ/cm.sup.2. The pattern resolution, which was the critical 
resolution at an exposure dose for reproduction of a line-and-space 
photomask pattern of 0.35 .mu.m line width, was 0.23 .mu.m. 
The cross sectional profile of the patterned resist layer of 0.35 .mu.m 
line width as examined on a scanning electron microscopic photograph was 
excellently orthogonal standing upright on the substrate surface. Although 
slight waviness was found on the side lines of the cross sectional 
profile, the cross section was not trapezoidal narrowing upwardly. 
EXAMPLE 8 
A chemical-sensitization negative-working resist composition was prepared 
by dissolving, in 500 parts by weight of propyleneglycol monomethyl ether 
acetate, 100 parts by weight of a copolymeric resin of p-hydroxystyrene 
and styrene in a molar ratio of 85:15 having a weight-average molecular 
weight of 2500 with a molecular weight distribution expressed by M.sub.w 
:M.sub.n of 1.23 and 10 parts by weight of a melamine resin (Nikalac 
Mw-100LM, a product by Sanwa Chemical Co.) to give a solution, in which 2 
parts by weight of .alpha.-(10-camphorsulfonyloxyimino)-4-methoxybenzyl 
cyanide prepared in Preparation 3 described above and 2 parts by weight of 
.alpha.-(methylsulfonyloxyimino)-4-methylbenzyl cyanide were dissolved and 
then 1 part by weight of 2,2',4,4'-tetrahydroxy benzophenone, 0.25 part by 
weight of triethylamine, 0.25 part by weight of tributylamine and 0.5 part 
by weight of salicylic acid were dissolved. 
A semiconductor silicon wafer was coated on a spinner with the thus 
prepared negative-working resist solution followed by drying on a hot 
plate at 100.degree. C. for 90 seconds to give a dried resist layer having 
a thickness of 0.73 .mu.m. This resist layer was pattern-wise exposed to 
excimer laser beams on the minifying projection exposure machine (Model 
NSR-2005EX8A, manufactured by Nikon Co.) followed by a post-exposure 
baking treatment at 120.degree. C. for 90 seconds and then the resist 
layer was subjected to a development treatment in a 2.38% by weight 
aqueous solution of tetramethylammonium hydroxide at 23.degree. C. for 65 
seconds followed by rinse with water for 30 seconds and drying. The 
exposure dose corresponding to the sensitivity of the resist composition 
was 37 mJ/cm.sup.2 and the pattern resolution was 0.22 .mu.m. 
The cross sectional profile of the patterned resist layer of 0.35 .mu.m 
line width as examined on a scanning electron microscopic photograph was 
excellently orthogonal standing upright on the substrate surface as in 
Example 7. 
EXAMPLE 9 
A chemical-sensitization positive-working resist composition was prepared 
by dissolving, in 400 parts by weight of propyleneglycol monomethyl ether 
acetate, 30 parts by weight of a first polyhydroxystyrene resin having a 
weight-average molecular weight of 10000, which was substituted by 
tetrahydropyranyl groups for 40% of the hydroxyl groups, 70 parts by 
weight of a second polyhydroxystyrene resin having a weight-average 
molecular weight of 10000, which was substituted by 1-ethoxyethyl groups 
for 40% of the hydroxyl groups, 5 parts by weight of 
bis(cyclohexylsulfonyl) diazomethane, 1 part by weight of 
bis(p-tert-butylphenyl)iodonium trifluoromethane sulfonate and 1 part by 
weight of .alpha.-(1-naphthylsulfonyloxyimino)-4-methoxybenzyl cyanide 
prepared in Preparation 1 described above followed by filtration of the 
solution through a membrane filter of 0.2 .mu.m pore diameter. 
A semiconductor silicon wafer was coated on a spinner with the thus 
prepared positive-working resist solution followed by drying on a hot 
plate at 90.degree. C. for 90 seconds to give a dried resist layer having 
a thickness of 0.7 .mu.m. This resist layer was pattern-wise exposed to 
excimer laser beams on the minifying projection exposure machine (Model 
NSR-2005EX8A, manufactured by Nikon Co.) immediately followed by a 
post-exposure baking treatment at 110.degree. C. for 90 seconds and then 
the resist layer was subjected to a development treatment in a 2.38% by 
weight aqueous solution of tetramethylammonium hydroxide at 23.degree. C. 
for 60 seconds followed by rinse with water for 30 seconds and drying. The 
exposure dose, by which the resist layer in the exposed areas was 
completely dissolved away, corresponding to the sensitivity of the resist 
composition was 5 mJ/cm.sup.2. 
The cross sectional profile of the patterned resist layer of 0.25 .mu.m 
line width as examined on a scanning electron microscopic photograph was 
excellently orthogonal without waviness along the side lines and without 
upward narrowing though slightly trapezoidal.