JPH0210344A - Fine pattern forming material and method for increasing image contrast - Google Patents

Abstract

PURPOSE:To improve the sensitivity, the resolution and the dry-etching resistance of a resist layer due to exposure of a short wavelength ray by composing a resist layer of an alkali-soluble resin and an aliphatic diazoketone as a main component. CONSTITUTION:The resist layer composed of a composition contg. the alkali- soluble resin and the aliphatic diazoketone (A) as the main component is formed on a substrate, and a fine pattern is formed by exposing the resist layer with a UV ray having 180-300nm (for example, a KrF excimer laser beam). The upper layer of a two layers resist is composed of an alkali soluble silicone resin and the composition contg. the component A as the main component. The component A is preferably composed of derivatives such as cholic acid, etc. (for example, a compd. shown by formula I) or a satd. aliphatic polyhydric alcohol (for example, a compd. shown by formula III). In the formula, R1 is hydrogen atom or 1-10C alkyl group, R2 is hydrogen atom, R3 is an org. group, R4 is a residual group except hydroxyl group from polyhydric alcohol, (m) is >=0, (n) is >=1.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The invention relates to a method for forming a fine resist pattern at a submicron level and a method for enhancing the contrast of a resist image. Used for formation.

[Conventional technology]

In recent years, with the remarkable improvement in the degree of integration of semiconductor devices, etc., 1.
- A method of forming patterns with extremely small widths and intervals with high precision is desired.

Conventionally, a reduction projection exposure method using g-line (436 nm) or i# (365 nm) light has been used as a pattern forming method for manufacturing LSIs. However, in these UV-yf, t-based and lithographic techniques, the resolution limit is theoretically 4 Mb.
It is expected that the minimum line width of D-M is about 0.8 μm, and as a result, it is estimated that it is difficult to apply conventional phosphorography technology to the production of D-AM of 16 Mb or more.

Therefore, a new resist material for 0.5 μm t-scale image, which is the minimum line width in 16 to l b D RAM, was developed.
Research regarding processes and equipment has been actively conducted in recent years, and phosphorography using shorter wavelength light (180 to 300 nm) has been attracting attention. Among these, at present, excimer laser reduced projection path light technology using KrF (249 nm) is attracting attention as a powerful lithography technology for eliminating line widths of 0.5 am or less.

However, there is no resist material that has sufficient characteristics as a resist for such short wavelengths. Now, Kr F
(249nm)-! - Taking ximer laser phosphorography as an example, its problems are described below.

That is, the novolak resist (composition of novolak resin and naphthoquinonediazide sulfonic acid ester) that has been used practically has poor light transmittance at 249 nm because the base polymer and photosensitizer contain aromatic rings.
The buffing source does not reach the bottom of the resist. Furthermore, the free lamp effect of the photosensitizer that brings about high resolution does not occur. Therefore, good patterns cannot be obtained with these resists by KrF excimer laser irradiation. -10,000, 249nmK
In order to improve the light transmittance of the resist in
PMMA-based resists that do not contain PMMA have been evaluated as excimer laser resists, but although these resists can produce good patterns, they have poor sensitivity and do not contain aromatic rings, so they cannot be used in reactive ion etching ( R.I.E.
) is less resistant to

On the other hand, in terms of process, a multilayer resist method has been proposed as a method for forming submicron patterns on a stepped substrate. The multilayer resist method includes a three-layer resist method and a two-layer resist method. In the three-layer resist method, an organic flattening film is coated on a stepped substrate, an inorganic intermediate layer and a resist are layered on top of it, the resist is buttered, the inorganic intermediate layer is dry-etched using this as a mask, and then an inorganic intermediate layer is layered. Using the layer as a mask, apply the organic planarization film to 0.000. This is a method of υ patterning using RIE.

Research on this method was started early on because it basically allows the use of conventional technology, but the process is extremely complex and requires three layers of organic, inorganic, and organic films with different physical properties. The problem is that cracks and pinholes are likely to occur in the intermediate layer. In contrast to this three-layer resist method, the two-layer resist method uses a resist that has the properties of both the resist of the three-layer resist method and the inorganic intermediate layer, that is, a resist that is resistant to oxygen plasma, which prevents cracks and pinholes. The generation is suppressed, and the process is simplified because the three-layer method is changed to a two-layer method.

However, in the three-layer resist method, a conventional resist can be used as the upper resist layer, whereas in the two-layer resist method, a new resist that is resistant to oxygen plasma must be developed.

Thus, until now, no resist material with excellent sensitivity, resolution, and RIE resistance has been found as a resist sensitive to ultraviolet light of 180 to 300 nm, including KrF excimer laser. A resist with excellent oxygen plasma resistance that can be used as an upper layer resist, and a pattern forming method using it, have not yet been developed. Literature regarding the evaluation of commercially available resists using KrF shimmer lasers includes a report by Endo et al. (IEICE Technical Research Report, Vol. 86, No. 139, p. 1 (1987)).

However, it is known that in the reduction projection exposure method, the contrast of the exposure light is worse than in the contact exposure method, so that the resolution of the resist is lowered. Therefore, in order to increase the contrast of V-cyst ratio, process studies are being carried out, and the CEL method (Contrast Enhancement
Lithography) is attracting attention.

The CEL method is an efficient (bleaching) method using light irradiation (for example, using a dye,
This is a method of providing a layer that increases the transmittance at that location when a certain amount of light hits it.

For example, in Japanese Patent Application Laid-open No. 59-104642, 300~
A CEL method using arylnitrone compounds that is effective at 450 nm has been proposed.

However, the method using the above-mentioned compounds has a
It is not effective against ultraviolet light of nm or less (and cannot be used for KrF excimer lasers).

From the above viewpoints, it is desired to develop a high-resolution lithography technique that is effective for KrF excimer laser sources and the like.

[Problem that the invention seeks to solve]

As mentioned above, in the conventional pattern forming method using a g-line stepper, the minimum line width of t6Mb DRAM, 0,
It cannot be resolved to 5jm. Also, currently, K.
When exposure is performed with short wavelength light of 180 to 300 nm, such as rF excimer laser, conventional resist materials cannot satisfy all characteristics such as sensitivity, resolution, dry etching resistance, and transfer accuracy, and cannot be put to practical use. there were.

The object of the present invention is to provide a resist material containing an alkali-soluble resin and an aliphatic diazoketone as main components that have extremely excellent sensitivity, resolution, and plasma resistance, and which simultaneously satisfies the above conditions and is highly practical. The object of the present invention is to provide a method for forming a pattern, and to provide a method for enhancing the contrast of a resist image in a photolithography technique using ultraviolet rays in the range of 180 to 300 nm in the manufacture of integrated circuits, etc., and a material therefor.

[Means to solve the problem]

In order to achieve the above object, the inventors investigated various materials and found that a photosensitive resin composition containing an alkali-soluble resin and an aliphatic diazoketone as the main components was used as a single-layer resist, and an alkali-soluble organosilicon We have found that it is effective to use a photosensitive resin composition containing resin and aliphatic diazoketone as main components as a two-layer resist to reshape fine patterns.

First, the inventors took into account that the resist materials currently in practical use are positive-type resists using an alkaline development method, and in order to be able to use them without changing the current process, they were exposed to an ultraviolet set of 1l80-300n. We decided to consider alkali-developable positive resists as single-layer and 21@ resists.

Common alkali-developable positive photoresists include compositions of an alkali-soluble cresol novolac resin and a photosensitive dissolution inhibitor, 7-toquinone diazide sulfonic acid ester. However, as described above, although these resists have excellent resistance to reactive ion etching (RIE), their sensitivity and resolution do not reach a practical level. Therefore, regarding the alkali-soluble base polymer and photosensitive dissolution inhibitor, we decided to search for the optimal material for resists sensitive to 180 to 300 nm ultraviolet rays. Considering the following, we can see that ■The light transmittance at short wavelengths is large;■
Two reasons are high IE resistance. Considering only the required property (1), copolymers of methacrylic acid and methyl methacrylate are excellent, but their resistance to IE is insufficient. In order to improve RIEita', it is necessary to introduce an aromatic ring into the base polymer. −
However, considering only the required property (1), cresol novolak resin is good, but light transmittance at short wavelengths is poor. In order to make the epithelium transparent to light, it is necessary to reduce the number of aromatic rings. For example, considering the use of KrF excimer laser, the aromatic ring required to achieve IB resistance is 249 n
The required characteristics ■
It is very difficult to supplement , (2) at the same time, but in any case, it is necessary to include an aromatic ring in the base polymer. Therefore, among the alkali-soluble resins containing aromatic rings,
As a result of examining various materials with the aim of finding a resin with excellent light transmittance at 2490 m, the following formula (6)
, (7) and (8) have relatively excellent light transmittance at 249 nm and a film thickness of jl.
It has been found that it exhibits a transmittance of over 50 at 1 m.

The main properties required of the base polymer of the KrF excimer laser resist for the two-layer resist method are (1) excellent light transmittance at short wavelengths, and (2) excellent RIB resistance.

Therefore, as a result of searching for an alkali-soluble resin that can simultaneously satisfy the above two properties, we found that the main chain contains a silicon atom, all or part of the side chain is an organic group containing a phenolic hydroxyl group, and the above-mentioned organic group is It was discovered that an alkali-soluble organosilicon resin containing hydroxyl groups and having bilateral symmetry with respect to a plane perpendicular to the benzene plane is good. As such a resin, for example, the following formulas (9) and (10
), (11), and the like, and specifically, for example, the following formulas (12), (
13) and (14).

0H (R1,O<aC πS i03/2)j(11) However, B,, lump, 几1, lump, 0, a is a C3 to C6 alkyl group, R, B''rIs8, is a trialkylsilyl group, d and k are 1 or 2.a, e%h are positive integers not including zero, b, c・f, g・i−j are positive integers including zero, a/ (a+b+c), e/(e+f+g
), h/(h+i+j) is equal to or larger than α4.

On the other hand, the main characteristics required of a photosensitive dissolution inhibitor for resists for short wavelengths of 180 to 300 nm are: (1) High light absorption at short wavelengths. ■The quantum yield of the photoreaction is high. ■In addition to the fact that the photoreaction product has no absorption in the 180 to 300 nm range, there is also a large difference in the alkali dissolution inhibition effect before and after the photoreaction, and that it is highly compatible with the base polymer. , or having appropriate crystallinity are also important factors. Naphthoquinonediazide sulfonic acid ester, which has been conventionally used for UV, has an aromatic ring in its molecule, so it does not satisfy the required property (2) and cannot be used for short wavelengths. Therefore, so that the photoreaction product does not have light absorption in the 180 to 300 nm range,
We decided to investigate aliphatic diazoketones that do not contain aromatic rings. First, as a result of examining t-11 aliphatic diazoketones that satisfy the required properties ■■■, it was found that the compound represented by the following general formula (15) is an aliphatic diazoketone that satisfies the above properties.

It is a C1-C1 alkoxy group. However, these compounds do not have the characteristics generally required as photosensitive dissolution inhibitors, such as large differences in dissolution inhibition effect, compatibility with base polymers, or moderate crystallinity, and cannot be used as is. That was difficult. Therefore, as a general rule, as a result of searching for a high molecular weight matrix that can be bonded by ester bond, we found that cholic acid, deogycholic acid, and lithocholic acid derivatives represented by the following general formulas (11 to (3)) and (16) to (19) We have found that the saturated aliphatic polyhydric alcohol derivatives shown below are good.

Here, R,, R1, is a monovalent organic group that does not contain an aromatic ring, and specifically, the lump is a C1-("II alkyl group or C
H.

C(CH,OR,,)4(BqρCH,), C-CHρCH,-C(CH,
OR,,).

Bird, 0+ Mouse.

However, 8 is H or an alkyl group of C3 to C1, and bird is H or a group obtained by removing R14t- from the general formula (15),
Except when all of the 0 and 3 groups are OH groups (also genus).

is a group obtained by removing R,, t- from formula (15).

Next, a method for forming a fine pattern using the photosensitive resin composition of the present invention will be explained.

Alkali-soluble resin (These resins may be used alone or in a mixture.) t-50 to 95M
weight ratio of 50 to 5 weight ratio of aliphatic diazoketone (if aliphatic diazoketone is used in an amount exceeding this range, it is unfavorable in terms of sensitivity and plasma resistance. A photosensitive resin composition consisting of (a mixture of a plurality of substances may also be used) is dissolved in a general-purpose organic solvent such as ethyl cellosolve acetate and used as a resist solution.

This resist solution is spin coated and prebaked under predetermined conditions. Next, a desired pattern is exposed using a KrF excimer laser stepper or the like, and by selectively dissolving only the irradiated portion using an alkaline aqueous solution, a positive pattern with a good shape can be obtained. Furthermore, the formed pattern exhibits excellent resistance to RIB such as CF, and sufficiently functions as an etching mask.

Similarly, a method for forming a fine pattern using a two-layer resist method will be described below.

Alkali-soluble organosilicon resin (these polymers may be used alone or in a mixture) t-
60 to 95% by weight and a total of 40 to 5% by weight of aliphatic diazoketone (if an amount of aliphatic diazoketone exceeding this range is used, it is unfavorable in terms of sensitivity and oxygen plasma resistance. Note that aliphatic diazoketone is A photosensitive resin composition consisting of (can be a single substance or a mixture of multiple substances) is dissolved in a general-purpose organic solvent such as ethyl cellosolve acetate and used as the second layer resist solution. .

Next, an outline of the two-layer resist method using the above photosensitive resin composition will be described. First, as the first resist layer of the two-layer resist method, a commercially available positive resist (for example, A
Z1350J, Microposite 1600 series, Tokyo Ohka OJ'P 800, etc.) or polyimide resins (for example, Hitachi Chemical PIQ, etc.) can be used. These base leveling materials sufficiently flatten the unevenness of the substrate, sufficiently absorb the exposure light of the second resist e, and are completely free from corrosion during coating, development, and rinsing of the second resist layer. .

These base planarizing materials are spin-coated and hard-baked under predetermined conditions to form a tg-resist layer. On top of this
The second layer resist solution is spin coated and prebaked under predetermined conditions to form a two layer resist. Next, the upper layer is exposed to a desired pattern in the same manner as described above, and only the irradiated portions are selectively dissolved using an alkaline developer to form a positive resist pattern on the upper layer. When this is treated with dry etching using oxygen plasma (referred to as reactive ion etching or IB), it is possible to process the lower layer (1 g - resist layer) ft using the upper resist pattern as a mask.

At this time, depending on the purpose, the processing shape of the lower layer may be adjusted to 0. It can be controlled by the oxygen gas pressure (Po, ) in the RIB. A relatively low oxygen gas pressure (Po, <several mtorr) is desirable to obtain a high aspect ratio vertical shape.

By using the above-described two-layer resist process, microfabrication at the submicron level can be easily performed with an aspect ratio of at least 3 or more.

In addition, in order to develop a method for enhancing the contrast of resist images, the present inventor conducted various studies on materials and processes, and found that: (1) A polymer film containing a compound that is efficiently bleached by irradiation with ultraviolet light of 180 to 300 nm; ■ Since the general-purpose phosphor-e-e process uses an alkaline aqueous solution development method, the materials and processes described in ■ can be applied to the alkaline development method. We have found that it is better to provide more than 2M.

As a result of searching for compounds that exhibit an efficient bleaching action when irradiated with ultraviolet light of 180 to 300 nm as described above, it was found that aliphatic diazoketone compounds are good. Such aliphatic diazoketones include
A saturated hydrocarbon skeleton having a hydroxyl group in the side chain is used as a matrix, and an aliphatic diazoketone group is permeated from the hydroxyl group of the matrix f'L
It was discovered that compounds characterized by being bonded to the parent body through an ester bond are good. The aliphatic diazoketone group is represented by the following formula.

Lump -c -c -(20) However, the mountain is a monovalent organic group that does not contain an aromatic ring.

In addition, as compounds whose entire base is a saturated hydrocarbon skeleton having a hydroxyl group in its side chain, examples include bicyclo compounds having a hydroxyl group as shown below, lithocholic acid, deoyacocholic acid, cholic acid and their derivatives, and saturated aliphatic polyhydric alcohols. Examples include.

In the following margin, 几 is an alkyl group of H or (C, ~C1,), and the compounds used in the present invention must be bonded to these parent bodies through at least one diazoketone-based ester bond. In other words, H of these parent hydroxyl groups may be converted into at least one of the following formula (21).

R-, -C-C-(knee)
(21) These compounds have a large absorption band in the 180 to 300 nm region, and when irradiated with light, they change to carboxylic acids, the light absorption intensity decreases greatly, and they exhibit excellent bleaching action. However, these compounds do not have sublimation properties, have excellent solubility in general-purpose solvents, and can be used in the same way as photosensitizers for general-purpose positive resists.

The method and materials of the present invention are particularly suitable for excimer laser lithography.

Hereinafter, 9 will be explained using a compound having a steroid skeleton as an example.

Useful compounds derived from cholic acid, deoxycholic acid or tritocholic acid are as follows - formula % A ring-free monovalent organic group, such as one of the descendants of C, -C, W%R0, 几4 is -H%-OH,
(22) contains at least one α-diazoacetoacetate group.

The above-mentioned α-diazoacetoacetate can be synthesized as follows.

Out! A raw material is cole, thioxycholic acid, a6-11') t:y-ylic acid, W ester form of the starting material (here, 1) with one organic group that does not contain an aromatic ring at the 5-terminal end.
For example, alkyl groups of %C, -we, etc. are preferable), or at least one of the hydroxyl groups of the reduced product of the starting material is transesterified with acetoacetate under an acid catalyst, or Using a reaction with diketene under a catalyst, etc., it is converted to an acetoacetate group, and the following -
A precursor corresponding to general formula (22) shown by formula (25) is obtained.

However, L, R"t!-Co, Hl-Co, R"o!
A type selected from H-CH, 0C-CH, -♀ C-CH, R'%几', R@ is,
-H%-O ratio formula (23) contains at least one acetoacetate group. Then, when the acetoacetate group f is converted into an α-diazoacetoacetate group using a reaction between P-toluenesulfonyl azide and an amine, the α-diazoacetoacetate group of the present invention shown in formula (22) is obtained. generate.

Useful compounds derived from saturated aliphatic polyhydric alcohols can also be obtained in the same manner as for the steroidal compounds described above.

Next, using the aliphatic diazoketone compound described above,
A method for increasing the contrast of a resist image, that is, a method for obtaining a resist image with high contrast will be described.

First, as one method, a polymer containing the above-mentioned aliphatic diazoketone compound/1ilt-spin coating is applied onto a resist layer formed on a substrate, and then exposed and
One example is a method of developing. As mentioned above, the polymer layer is not particularly defined, but it is desirable that it has high transparency to the exposure light used, and it is preferable to Examples of polymers include phenol novolac, cresol novolac, polyvinylphenol, and alkali-soluble ladder silicone polymers. In particular, when considering alkaline development, it is desirable to use a polymer that dissolves in an alkaline aqueous solution.

The film thickness is preferably 0.05 to tOsm, and the aliphatic diazoketone compound is added to the polymer by 5 to 50 tOsm.
It is desirable to contain it in parts by weight.

Incidentally, the aliphatic diazoketone compound and the above-mentioned polymer material dissolved in a general-purpose solvent such as ethyl cellosolp acetate or cyclohexanone are applied by spin coating or the like.

Another method for obtaining a resist image with high contrast is to provide two layers of resist with different bleaching properties and obtain a resist pattern by exposure and development. That is, two layers of resist # are provided using a polymer containing the aliphatic diazoketone compound of the present invention,
The upper layer should be formed so that it has thicker bleaching characteristics than the lower layer against the exposure light used.The method is to use an upper layer resist that contains a large amount of the same aliphatic diazoketone compound, The lower layer resist may be formed using a method containing a small amount of diazoketone or a different type of aliphatic diazoketone so that the upper layer has greater bleaching properties than the lower layer.

Polymers for resists are not particularly limited, but are suitable for use with current alkaline development methods.
Alkali-soluble polymers are preferred, such as polyvinylphenol, cresol novolak, phenol novolak,
Examples include alkali-soluble ladder silicone polymers. The thickness of the resist layer may vary depending on the application, but the thickness of the upper and lower resist layers is 0.2 to 11, respectively.
It is particularly good if mb is 0.3 to 2.0 pm. The ratio of polymer to aliphatic diazoketone compound is 100
It is desirable that the amount of O is 5 to 50 parts by weight based on the weight part.In addition, considering that alkaline development is carried out after photo-lighting,
It is desirable that the upper resist layer dissolves more easily than the lower resist layer, but this is especially true in this case.

[Effect]

In the photosensitive resin composition of the present invention, the alkali-soluble resin contains an aromatic ring, thereby maintaining the excellent RIE resistance of conventional resist materials, and the use of the alkali-soluble organosilicon resin, which is necessary for the two-layer resist method. NaO,
It is thought that the fact that it exhibits RIE resistance and has excellent light transmittance at short wavelengths in both cases helps improve sensitivity and resolution. In addition, the use of aliphatic diazoketones makes photosensitive dissolution inhibitors highly efficient (reacts with light at short wavelengths), and the light absorption at short wavelengths of the reaction product is small, resulting in a bleaching effect. This is thought to have improved sensitivity and resolution. By combining the above two components, it is possible to obtain excellent resist properties against ultraviolet rays of 180 to 300 nm from KrF excimer lasers, etc. A fine pattern with a fine pattern of 180 to S 00 can be obtained.
Because it uses a compound that can be efficiently bleached by irradiation with nanometer ultraviolet rays, patterns with extremely high resolution can be obtained with high precision in excimer laser lithography and the like.

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to synthesis examples and examples, but the present invention is not limited to these synthesis examples and examples.

Synthesis Example 1 In a 100-meter flask equipped with a reflux tube, a dropping funnel, and a stirring bar, 2.11/(5,
00 tmol), 10-1 t4-dioxane, and 0.14F of P-toluenesulfonic acid aqueous solution were added, and the mixture was heated to reflux. While stirring, diketene t 68 P (2
00 mmol) in 10 m solution of t4-dioxane f: 4
Add it dropwise at 0 minutes and let it ripen for 1fft-4 hours. After the reaction is complete, the solvent is distilled off under reduced pressure. The L1 residue is dissolved in diethyl ether and washed with water and saturated brine. After drying over anhydrous sodium sulfate, diethyl ether was distilled off and the following compound was isolated by one column chromatography.

Dry with thorium. Diethyl ether was distilled off under reduced pressure, and the residue was re-crystallized from ethanol to obtain the following title compound. Yield: 148. P, yield 8゜yield t56
'p・Yield: 60.5. NMR spectrum (60MHz
, CDC1,) characteristic peak: A (J2.17.
2.20 Pupil C (δ3, 55; -C-0-CH,), intensity ratio A:B:C-5:2:1°Characteristic peak of TR spectrum: 170ocm (C-0).

Next, in a Futuro flask equipped with a reflux tube and a stirrer,
Compound t56J' (2,3) mmol) synthesized above
, triethylamine α77JF (7.62 mmol) and acetonitrile 10s# were added, and a gold solution of P-toluenesulfonyl azide t50/(7.62 mmol) in acetonitrile 5d was added dropwise. After stirring at room temperature for 2 hours, the solvent was removed under reduced pressure. The diethyl ether solution was washed with an aqueous potassium hydroxide solution and saturated brine, and then diluted with anhydrous sulfuric acid, melting point 13.
9℃. NMRI Spec) #(60MHz.

CDCI, ) characteristic peak: A(δ2.42.2.
46; CH, -C-), B (J5.60; -C-OC
H,), intensity ratio A2B-6=1°Characteristic peak of TR spectrum: (2160--1; JC-N,), (17
50m-1,1675m-”; y e-o).U
V spectrum (in CTHF): 2 max 258n
m, a 24,300°Synthesis Example 4 In the same manner as Synthesis Example 1, by using 2.2 times the amount of diketene relative to Colebee methyl and performing exactly the same operation,
The title compound was obtained.

Synthesis Example 5 NI The diketene used in Synthesis Example 1 was used in an amount of 111 times the amount of methyl cholate, and the same operation as in Synthesis Example 1 was performed to obtain the title compound.

Cole-n-propyl 5.117' (1t5mmo
l ), jigte y 3.81 F (45,4nmo
1) and P-toluenesulfonic acid hydrate 0.44.
P to 5 synthesis gAJ1 Call (35-n
After synthesizing a compound in which three acetoacetic acid ester groups were introduced into -propyl (yield: 8725), 6.097 (30.9 rrmol) of P-toluenesulfonyl azide and 3.9 mmol of triethylamine were synthesized without isolation by column chromatography. 14/(30.9 mnol) was subjected to t-reaction, and diazotization was performed in the same manner as in Synthesis Example 1.The reaction residue was recrystallized from a mixed solvent of total acetic acid, ethyl ethyl, and hexane. Compound f4.56P was obtained. Yield: 463
．． 0chi. Melting point: 110-112°C. NMI (Spec intensity ratio A
:B-9:2°Characteristic peak of IR spectrum: (2
160cm ” ;JC-N, ), (1720fi ”
, 1680a+'', yc-o)o U V x vector CTHF): 2 max 258nrii,
523800° Synthesis Example 5 N.

Methyl lithochlate t95J' (5,00 face o1), Diketey Q, 50/ (&Orrmol), and P
-) Aqueous 57'F of toluenesulfonic acid was reacted in 3 g of 1,2-dichloroethane 7F in the same manner as in Synthesis Example 1, and the residue was recrystallized from methanol. After synthesizing the compound into which the ester was introduced (yield t 4410 yield 6Q, 7chi. melting point 184-189°C), P-) luenesulfonyl azide 0.60 J' (3, Orrmol) and triethylamine Q, 3) J '(5,0 mmol), Synthesis Example 1
Diazotization was carried out in the same manner as above. The title compound was isolated from the reaction residue by column chromatography at t1.
I got 2J'. Characteristic peak of yield: (2160m
"; yc-N, ), (1755fi", 1750
cm-1; vc-0). UV spectrum (in CTHF):
λ max 258nm% δ6,600° Synthesis Example 6 100d30 equipped with a reflux tube, dropping funnel and stirrer
In a flask, add ethyl cholate 11111JF (22,9
rrmo 1 ), 1,4-dioxane 30-1 and P-toluenesulfonic acid-hydrate 0.727' (58
mno 1) and diketene 6 while heating and refluxing.
．． 41 (76 mmo 1 ) of 1,4-dioxane 1
- Add the solution dropwise over about 40 minutes and age for 4 hours. After completion of the reaction, the solvent was distilled off under reduced pressure, and the L1 residue was dissolved in diethyl ether, washed with water, then with saturated brine, and dried over anhydrous sodium sulfate. The ether was distilled off and the following compound 13.17
(19,0rrmol) was obtained.

Dry in a lium. Diethyl ether was distilled under reduced pressure to obtain the target compound as a yellow oil at 5.87' (7.6 rrm
o l) Obtained. Yield: 40%.

The above-mentioned superprecursor 13. To a solution of IP (19 rrmol), triethylamine 9,1 d (65 rrmol) and acetonitrile 20 d, a total of 10 g of acetonitrile solution of P-toluenesulfonyl azide 1t8/(60 mnol) was added dropwise at room temperature. The solution slowly generates heat. After stirring at room temperature for 2 hours, the solvent was distilled off under reduced pressure, and the mixture was completely extracted with diethyl ether. The diethyl ether solution (g) was shaken several times with an aqueous potassium hydroxide solution to remove the 1-taP-)luenesulfonylamide produced by the reaction, and then washed with water.
After washing with saturated saline, anhydrous sulfuric acid sodium chloride B (δ190,
Quadruple # (6Hz), -C-0 (H, -CH,) intensity ratio A
:l3-9:2 IR, characteristic peak of spectrum A (2160ea-νc, N,) B (1720fi-', 168Qes+1, y(-□)
UV spectrum (THIi" A) λmax 25 anm, g 24000 Synthesis example 7 Cyclohexyl cholate 6.297' (12,8 mn
ol) Diketene 3.55 J' (42,2m+nol
) and p −) /l/ x y from 0.5 J' (2,5 mnol) of sulfonic acid hydrate, Synthesis Example 6
The following compound was obtained in the same manner as above.

This compound "f, Jet i, P-toluenesulfonyl azide 7.47' (37.5 mnol
) and Trieteravan 58.1 (4t3 claw n
ol) was reacted with acetonitrile 25d, and diazotization was performed in the same manner as in Synthesis Example 6. The product was then crystallized from a mixed solvent of ethyl acetate and hexane to obtain the pure target product as pale yellow crystals t72J'. Melting point 9
9-101℃ Ni'vl B spectrum (60MHz, C1) C
Characteristic peaks of L s ): A (a2.42.2.40; CM, -(! knee) ■ 13 (J4.07, multiple @ (6Hz'), -c -
o -g Q) Intensity ratio A:B-9:1 1 Characteristic peak of R spectrum; A(2170'', v(-N, )B(17506
I+-1,168C1g 1;,,o) UV spectrum (T) (in F') λmax 259nm % *21400 Synthesis Example 8 Tetrahydric alcohol 1 obtained by reducing the carboxyl group of cholic acid
95 J' (10 mnol), diketene 4.20p
(48/m1o1), P-) Luenesulfonic acid hydrate 0°92/(4.8 mmol) t1.4-dioxa 740 dlc 1 ft of the following compound was obtained by the same operation as in Synthesis Example 5 as a solvent.

Synthesis Example 9 The above compound thus obtained, P-toluenesulfonyl azide 8.17JF (4t4mmol), triethylamine 6.4w (a 5.5rrmo!)
'k, acetonitrile 30, J was used as the f3 medium and the same procedure as in Synthesis Example 5 was performed to obtain the target compound as a yellow oil in an amount of 5.18/(6,2 Qrrmol). Yield: 62 cm.

NMRxPect/I/ (60Mk4 z -CD C
Q s ) characteristic pin N.

Dihydric alcohol obtained by reducing the carboxyl group of lithocholic acid 5.63) (10rrmol), diketene 2.0
2.5' (24+nno l ), P-toluenesulfone hydrate 046t (2,4 rmol) e 1 ,
Using '-dioxane 4(]J'i as the solvent, the following compound 4.86J' was obtained by the same procedure as in Synthesis Example 5.

Characteristic peak A (2160”, y c -111i, ) B (
1750" - 1675", vc-Q) UV spectrum (T) (in F) λmax 259 nm, g28900 P-) luenesulfonyl azide 5.97 P C2 in the precursor obtained above
0,2+rmol), triethylamine 6.1, #(
22,2rywnol), acetonitrile #20. 517 J' (5,44rrmo
l) was obtained. Yield: 54 cm.

Characteristic peak of characteristic IR spectrum of NMR spectrum #(60MH2%CDCl2.): A(21604'; w C-N, )B(1740
elI", 1675al' i v.-wQ) UV
Spectrum (in THF): 100-30 with reflux tube, addition funnel and stirrer
In the flask, add 2.72P of pentaerythritol (G, 0
20 mol), a catalytic amount of P-)luenesulfonic acid-
A solution of 7.06 p (0,084 mol) of diketene in 10@I of 14-dioxane was added dropwise to the hydrate and 10@I of t4-dioxane over 40 minutes while heating.
Time to mature. After distilling off the solvent under reduced pressure, the solution is made into a chloroform solution, washed with water, and dried over anhydrous sodium sulfate. Distilling off the chloroform gives a reddish-brown oil. Ethyl acetate:Hexane-4=1 solution, passed through a silica gel layer,
When the solvent is distilled off.

4.771 (0.01 mol) of acetoacetate, a precursor of the target compound, was obtained as a yellow oil.

Next, this was mixed with 5.4 ml of triethylamine (0.04
mol), acetonitrile 20-r solution. To this, P-toluenesulfonylua'))' 8. OJ' (
0.04 mol) (D7 Setonitrile 10d solution is added dropwise and stirred at room temperature.

After 2 to 3 hours, the solvent was distilled off to obtain a chloroform solution,
Shake well with aqueous potassium hydroxide solution, and P- produced by the reaction.
) After removing luenesulfonylamide, wash with water and dry with anhydrous sodium sulfate. After evaporation of the solvent, the residual yellow oil was passed through a silica gel-layered column, and the obtained hemahedron was recrystallized from ethyl acetate-hexane to obtain the pure target compound as pale yellow crystals (t82JF (α0032 mol)).
Obtained.

15.8% yield from pentaerythritol Melting point 1
08-109℃ NMRx vector (60MHz %CDC1,) a 2
．． 45 (12H%S, -C-CM, )14.27
(BH%B,-CH,-0) IR spectrum 2180g'(C-N,), 1740(C-0)
, 1680 (C-o) UV spectrum (in THF) λmax 253nm, gmax 30600
Synthesis Example 11 Using acetonitrile 60d, the target compound was obtained in substantially the same manner as in Synthesis Example 1o. Recrystallization was performed from ethanol. Since the target compound was hardly soluble in ethanol but impurities were soluble, the pure target compound was obtained as a pale yellow powder (t 57 J' (0,0017 mol)).

Yield from dipentaerythritol: 8.6.

Synthetic dipentaerythritol with a melting point of 132°C5. IJ' (α02mol),
The precursor acetoacetic acid ester #14. was prepared by the same procedure as in Synthesis Example 10 using t4-dioxane as a solvent from a catalytic amount of P-kx sulfonic acid hydrate (0.15 mol). OJ' (Q, 01
9 mol )'fr was obtained, and this and P-)luenesulfonyladi)"21,7J'(α11 mol)-triethylamine 15IIj (0.11 mol), 4.25 (
12H,S, -C-OCH,-) IR spectrum 2170=II-1(C-N,), 1730ea"(C
-0), t67o--' (c-o) UV spectrum (T
in HF) λmax 255nm s gmax 4620
0 combination example 12 i,4-cyclohexanedio-/I/2.57' (
0,022 mol), Dikety 4. OP (0,0
47mo! ), a catalytic amount of P-ntxysulfonic acid-
Synthesis Example 1 from hydrate to 1,4-dioxane as a solvent
By the same operation as in 0, 1921 (h75rrmol) of acetoacetate, a probiotic, was obtained as colorless crystals.

Precursor t50Jj (5,3rrmol), P-toluenesulfonyl azide2. I J' (10,6rrmo
l), triethylamine 15d (1tomnol
), acetonitrile 12. dt-react.

After 2 hours, the solvent was distilled off to obtain a methylene chloride solution, which was thoroughly shaken with an aqueous potassium hydroxide solution, washed with water, and dried over anhydrous sulfuric acid. When the solvent was distilled off, crude crystals of the target product were obtained. The pure target compound was obtained as pale yellow crystals by recrystallization from ethanol at 0.937'
(2.77 mnol) was obtained. Yield 52 from precursor
blood.

Melting point 117-118℃ HNMRX Pect/I/ (60MHz %CDC1m
) Jt4-2.2 (8H, m, methylene) a 2-4
0 (6H,8,-t5-CH,)J 4.7-5.2
(2H%m, methine)l spectrum 2170c11" (C-N, ), 1720ffi"-'
(C=0), L660e11-1 (C-0) UV spectrum (in THF) λmax 255nm #max 15600
Synthesis Example 16 Inositol 56PCα02mol), diketene 1to
p(0,15 mol), catalytic amount of P-)luenesulfonic acid-hydrate, t4-dioxane 4(IJ″Ik),
The precursor acetoacetate k f 8.671 (0,012 mol) was obtained by the same operation as in Synthesis Example 10 (however, methylene chloride was used instead of chloroform). This and P-toluenesulfonyl azide 15.8P
C0,07m01), triethylamine 9.5y(0
, 07 mol), acetonitrile 30 dt - Synthesis Example 1
After 9 days, the solvent was distilled off, extracted with methylene chloride, shaken with an aqueous potassium hydroxide solution, washed with water, and then dry-etched with anhydrous sodium sulfate. The solvent was distilled off to obtain crude crystals of the target compound. Impurities were removed with ethanol, and the pure target compound was converted into a light yellow powder as 08JF (
0,004 mol) was obtained. The yield from inositol is 20.

Melting point 165-154℃ 85.40-5.60 (6H, m, methine) Engineering R spectrum 2180Cm' (C-mN,), 1750ea-
' ((, '-0), 1670 cm '' (in UV spectrum (T)iE') It easily dissolves in alcoholic solvents, ketone bath agents such as acetone, ester solvents such as ena acetate/L/, and halogen solvents such as chloroform.
When irradiated with excimer laser or the like, it shows a good bleaching effect for 9' hours.

For example, the compound of Synthesis Example 1 has a UV spectrum in tetrahydrofuran of 2 max 258 nm, g2
It has a photosensitive region below 4300 and 300 nm.

Furthermore, at 249 nm, it is #22700, and the above U
V measurement + 40 using Xe-Hg lamp for y pull
Upon second light irradiation, g5400 and light absorption intensity decreased to about 1 at 249 nm.

Next, using the compound of Synthesis Example 1 as an example, the photoreaction product was
Tracking was carried out using R spectrum and NMR spectrum.

In the El spectrum, upon light irradiation, the absorption based on the diazo group disappears, and a new broad absorption based on the -OH of carboxylic acid appears at the center of 5200 fl'ft.
Absorption disappears, and due to carboxylic acid (absorption decreases to δ
It happened on 8.25.

From the above, when the compound of Synthesis Example 1 is irradiated with light, the following reaction occurs, and a carboxylic acid is produced.

Compounds of synthesis examples and alkali-soluble resins [novolak resin, polyvinylphenol, poly(P-hydroxybenzylsilsesquioxane), polyvinyl alcohol, etc.]
and cyclohexanone or 1-acetoxy-2-ethoxyethaneft were freely mixed in various amounts in a general-purpose solvent, and when these solutions were spin-coated onto a silicon wafer, a uniform coating film was formed. A uniform film was formed. Further, when weight loss due to heating was observed using a thermobalance, no sublimation of the compound of the synthesis example was observed.

Examples of the present invention are shown below.

Example 1 A first example of the present invention will be described below based on the process diagram of FIG.

The alkali-soluble resin shown in (6) above, 80 parts by weight of P-cresol novolac resin, 20 parts by weight of the aliphatic diazoketone obtained in Synthesis Example 1, and dissolved in gold 1-acetoxy-2-ethoxyethane, solid content 27 parts by weight. % resist solution.

Next, this resist solution was spin-coated onto the silicon wafer 1, prebaked at 85 to 90°C for 30 minutes, and
An am resist film 2 was formed.

In addition to this, the KrF excimer laser source with different irradiation doses is
249 nm) t [quaternary, developed with a 2.58% tetramethylammonium hydroxide aqueous solution for 1 minute, and then washed with water for 1 minute, and then the remaining resist film thickness was measured Lt. Then, the residual film thickness (normalized) is plotted against the exposure amount (J-m''), and the minimum exposure amount (sensitivity) at which the residual film thickness is zero is calculated.
When t- was determined, it was approximately 950 Jm-. Next, the resist film obtained in the same manner as above was subjected to reduction projection exposure (t 5KJ -m-) using a quartz mask, and then,
When developed in the same manner as above, 0.5 Jlrr J&S could be resolved.

Furthermore, the above resist pattern was formed and nine silicon wafers were placed in a parallel plate IFi device (Pc, -5,2
Pa, RF-52w-m-)t” using CF4R
When IE' (H) was performed, it was confirmed that the etching rate of the resist was approximately 20 nm-min-'', showing excellent RIB resistance.As described above, by using the present invention, extremely fine patterns can be It was confirmed that it could be formed.

Examples 2 to 35 Experiments were conducted in the same manner as in Example 1 under various conditions. Table 1 summarizes specific values regarding composition fraction, blending ratio, exposure light source, optimum exposure amount for sensitivity, development conditions, resolution, CF, and RIB rate. This confirms that extremely fine patterns can be easily formed using the method of the present invention.

Example 36 An example showing a method for forming a fine pattern using a two-layer resist method according to the present invention will be described below with reference to FIG.

First, 80 parts by weight of the alkali-soluble organosilicon resin (poly(P-hydroxybenzylsilsesquioxane)) shown in the above (14) and 20 parts by weight of the telephatic diazoketone obtained in Synthesis Example 1 were mixed with 1-7 setoxy 2 - It was dissolved in ethoxyethane to form a resist solution with a solid content of 27% by weight.

PFR-3650D4 (manufactured by Nippon Taisoko Rubber Co., Ltd.) is spin-coated on the silicon wafer 11 and hard-baked at 200°C for 30 minutes to form a film with a thickness of about 85 μm.
And so. The above resist solution was spin-coated on this first resist layer 12, and prebaked at 85° C. for 30 minutes.
A resist film 13t of 0.8 am was formed.

To this, KrF excimer laser light with various different irradiation doses (
249 nm), and the o, oso standard tetra(2-
Hydroxyethyl) ammonium hydroxide aqueous solution?
The remaining resist film thickness was measured after developing for 1 minute and then washing with water for 1 minute. Then, the residual film thickness (normalized) t
-11 light filter (J-m1) and calculated the minimum exposure amount (sensitivity) at which the residual film rate is zero, it was approximately 1oo
It was oJm-.

When the resist film having the two-layer structure was subjected to reduction projection exposure (t6KJ-m-) L using a quartz mask and then developed in the same manner as above, 0.5 μm Qk8 could be resolved.

Furthermore, the pattern of the upper resist layer was masked and a parallel plate type RIB device II (Pos-26P a,
RF=200W (14MHz), Cando bias voltage -130V)? Use, 0. When RIB y2 was performed, the upper resist pattern of α5smQIkB was transferred to PFR-4650D4 with good accuracy and an aspect ratio of 3 or more.

The dimensional shift was less than α1+m. At that time, the etching rate of the upper layer resist is approximately anm/min.
' It has been confirmed that it exhibits high resistance to HIE.

As described above, by using the present invention, extremely fine patterns can be formed, and they can be formed with a high aspect ratio and 0.
．． It was confirmed that transfer to the first resist layer was possible with a dimensional shift of 1+m or less.

Examples 67-62 Experiments were conducted in the same manner as in Example 36 under various conditions.

Components of the compositions of the first resist layer and the second resist layer, compounding ratio, light source, sensitivity, optimum exposure hammer, development conditions, resolution, 0. Specific values regarding the RJ E rate are summarized in Table 2. From this, it was confirmed that an extremely fine pattern could be formed by the method of the present invention, and that it could be transferred to the broom-resist layer with a high aspect ratio and a dimensional shift of 0.1 μm or less.

Embodiment 63 Next, an embodiment of the method for enhancing the contrast of an image according to the present invention will be described based on FIG.

General-purpose positive resist 3 formed on silicon wafer 3)
2 (e.g. AZ-2400 [5hipley model])
5 poly(P-hydroxystyrene) 80 on about 18, m
2 consisting of parts M and 20 parts by weight of the photosensitizer obtained in Synthesis Example 1
A 1-acetoxy-2-ethoxyethane solution of 0.0% was applied by spin coating, and prebaked at 85°C for 30 minutes to give a 0.0% solution.
A resist 53 having a thickness of 5 m was completely formed.

In addition, KrF excimer laser original 'i 300mJ/Cd
By irradiating, developing with tetramethylammonium hydroxide water solution for about 1 minute, and then rinsing with water, a fine pattern of 0.5 pm was formed with a spectral ratio of 7 to 2.
It was confirmed that a high aspect ratio pattern could be obtained extremely easily. Note that dew+i is not particularly limited and is 600 to 10001. VJ/
- A good pattern was obtained.

Further, even when an Xe-Hg lamp or an ArF excimer laser was used as a light source, a similar fine pattern with a high aspect ratio was obtained.

Examples 64 to 88 Positive photoresist 1-(AZ-2400,0FPR-) formed on a silicon wafer in the same manner as in Example 63.
800, TSM 几-3000, etc.) on about IJIm,
A polymer layer consisting of the polymer shown in Table 6 and a photosensitive agent was formed by spin coating, and prebaked to obtain a 0.0.
A resist having a thickness of 0.05 to 1.0 .beta.m was completely formed.

Excimer laser (e.g. KrF 249 nm, A
rF 195 nm), Xe-Hg lamp, high-pressure mercury lamp, or low-pressure mercury lamp, and tetramethylanthonium hydroxide or (
It was confirmed that a pattern with a high aspect ratio of 0.5 μm or less could be obtained by developing with a tetrahydroΦdiethyl]ammonium hydrometallide water P solution and rinsing with water.

Example 89 Next, an example will be shown in which two resist layers containing an aliphatic diazoketone compound were stacked in order to enhance the contrast of the image. The explanation will be given below based on Fig. W.4.

27I! consisting of 80 parts by weight of an alkali-soluble ladder silicone polymer and 20 parts by weight of the photosensitizer obtained in Synthesis Example 1 was placed on a silicon wafer 41. A quantity of 1-aceto-2-ethoxyethane solution was applied by spin coating and prebaked at 95° C. for 60 minutes to form a resist 42 with a thickness of +1.8 μm.

Subsequently, on this resist, 8 liquids of 1-7 setoxy-2-ethoxyethane of 15 parts each consisting of 70' fB, I kg of alkali-soluble ladder silicone polymer and 30 M parts of the specific sensitizer obtained in Synthesis Example 1 were applied. Spin coating and heat at 85℃/
A resist 43 having a thickness of 2×m was formed by prebaking for 30 minutes.

This is irradiated with KrF excimer laser light or Deep UV3 emitted from a Xe-Hg lamp (200 mJ/cJ
~800 mJ/d) L, a 0.75N aqueous solution of tetrahydroxyethylammonium hydroxide was heated for about 1 minute, and rinsed with water.
A fine pattern of α5sm or less was obtained with an aspect ratio of 2 or more, and it was confirmed that this method is extremely useful as a fine pattern forming method.

Examples 90 to 111 In the same manner as in Example 89, 2
A layered resist was formed on the entire silicon wafer.

In addition to this, KrF excimer laser light or X e -Hg
By irradiating with a deep UV source emitted from a lamp, developing with an alkaline aqueous solution for about 1 minute, and rinsing with water, a high aspect ratio pattern of α5am or less can be obtained in either case.

From the above results, it was confirmed that the method of the present invention is extremely useful as a method for forming fine patterns.

Table 4. Embodiments [Effects of the Invention] As described above, according to the present invention, a fine resist pattern with a high aspect ratio and a submicron level pattern size can be obtained with high accuracy. Moreover, since the alkali development process, which is currently the mainstream in semiconductor processes, can be applied as is, it is extremely advantageous in practice and is a very powerful technology for the manufacturing process of semiconductor elements and the like.

[Brief explanation of the drawing]

FIG. 18, 1-1) are diagrams showing an embodiment of the method for forming fine turns according to the present invention. FIG. 2 (al to ba) is a diagram showing an example of a method for forming a fine pattern using a two-layer resist method according to the present invention. FIG. 6 18, l to dl are diagrams showing an embodiment of the method for enhancing the contrast of an image according to the present invention. W, 4 Figure 18, l~(dl is a diagram showing another embodiment of the method for enhancing the contrast of a preserved stone image according to the present invention. 1.11.61.41...Silicon sea urchin/S2.13
．． 63.42.43...Resist 3.14.34.4
4...Resist pattern (e) Figure ↓ Shaku E ↓ f '/Ricoso wafer Z Resist 3 Resist pattern diagram Silicone wafer shift 1tWS Positive type resist resist (C iris LA) Resist pattern v; 2 Figure 1I Silicone wafer/ 2 V [Heiji fl Ihi,> 11! 3 Resist 14- Resist pattern No. 4- Figure 4-/ Silicon U28+2 Resist ■ 4-3 Resist ■ ++ Resist pattern

Claims (1)

[Claims] 1. A resist layer is provided on the substrate, and a resist layer of 180 to 300
A method for forming a fine pattern in which a desired portion is exposed to nanometer ultraviolet light and developed, wherein the resist layer is made of a photosensitive resin composition containing an alkali-soluble resin and an aliphatic diazoketone as main components. Pattern formation method. 2. A first resist layer is provided on the substrate, a second resist layer is provided on this, and this second resist layer has a
A fine pattern is formed by exposing a desired part to nanometer ultraviolet light, developing it to form a pattern in which the desired part of the first resist layer is exposed, and removing the exposed part of the first resist layer by dry etching. A fine pattern forming method, wherein the second resist layer is made of a photosensitive resin composition containing an alkali-soluble organosilicon resin and an aliphatic diazoketone as main components. 3. The method for forming a fine pattern according to claim 1 or 2, wherein the aliphatic diazoketone contains at least one type of aliphatic diazoketone derived from cholic acid, deoxycholic acid, and lithocholic acid. 4. In claim 3, cholic acid, deoxychole,
and an aliphatic diazoketone derived from lithocholic acid are derivatives represented by the following general formulas (1), (2) and (3), respectively. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ However, R_1 is H or an alkyl group of C_1 to C_1_0, R_3 is H or a diazoketone group shown by the following general formula (4), and all OR_3 groups are OH groups. except. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ Here, R_3 is a monovalent organic group that does not contain an aromatic ring. 5. In claim 1 or 2, the aliphatic diazoketone is represented by the general formula (5) using a saturated aliphatic polyhydric alcohol.
) A fine pattern forming method characterized by: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ However, R_6 is the residue obtained by removing the hydroxyl group from a saturated aliphatic polyhydric alcohol. m is an integer greater than or equal to 0, and n is an integer greater than or equal to 1. 6. The method for forming a fine pattern according to claim 5, wherein m and n in the saturated aliphatic polyhydric alcohol and formula (5) are each shown below. C(CH_2OH)_4, m=0, n=4 (HOCH_2)_3C-CH_2OCH_2-C(C
H_2OH)_3, m = 0, n = 6 ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, m = 0, n = 2 ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼, m = 0, n = 6 7. Request Item 1. The fine pattern forming method according to item 1, wherein the alkali-soluble resin contains at least one type of alkali-soluble resin represented by the following formulas (6), (7), and (8). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ 8. In claim 2, the alkali-soluble organosilicon resin is an organic group containing a silicon atom in the main chain and all or part of the side chain containing a phenolic hydroxyl group. A fine pattern forming method characterized by: 9. A fine pattern forming method according to claim 8, wherein the alkali-soluble organosilicon resin is any one of the alkali-soluble organosilicon resins represented by the following general formulas (9), (10), and (11). . However, R_5, R_6, R_8, R_9, R_1_0
, R_1_2 is an alkyl group of C_1 to C_■, R_7,
R_1_1, R_1_3 are trialkylsilyl groups, d and k are 1 or 2, a, e, h are positive integers not including zero, b, c, f, g, i, j are positive integers including zero. ,
a/(a+b+c), e/(e+f+g), h/(h+
i+j) is 0.4 or more. 10, in claim 1 or 2, 180 to 30
As a light source that emits 0 nm ultraviolet rays, ArF excimer laser, KrF excimer laser, Xe-Hg lamp, high pressure H
A method for forming a fine pattern, characterized by using a Hg lamp or a low-pressure Hg lamp. 11. In the step of forming a fine pattern by selectively exposing the resist layer and performing a development process, a polymer layer containing a compound whose light transmittance is effectively improved by irradiation with light of 180 to 300 nm is added to the upper layer of the resist. A method for enhancing the contrast of an image, the method comprising: 12. The method for enhancing image contrast according to claim 44, wherein the compound is an aliphatic diazoketone compound. 13. The method for enhancing image contrast according to claim 11, wherein the compound is a compound containing one or more α-diazoacetoacetate groups in the molecule. 14. Excimer laser (KrF laser,
12. The method for enhancing image contrast according to claim 11, characterized in that an ArF laser) or a mercury lamp is used. 15. In the process of selectively exposing the resist layer to light and developing it to form a fine pattern, the lower resist layer has a property that the light transmittance improves by light irradiation (bleaching property) is smaller than that of the upper layer. . A method for enhancing the contrast of an image, comprising providing a two-layer resist structure using a resist layer having the above characteristics as an upper layer. 16. In the resist layer, a resist containing an aliphatic diazoketone compound having high bleaching properties against light irradiation of 180 to 300 nm is used as the upper layer, and an aliphatic diazoketone compound having small bleaching properties compared to the material used for the upper layer is used as the upper layer. 16. The method for enhancing contrast of an image according to claim 15, characterized in that a resist containing the above-mentioned resist is used as a lower layer. 17. The method for enhancing image contrast according to claim 15, wherein in the resist layer, the upper resist layer contains more aliphatic diazoketone compounds than the lower resist layer. 18. The method for enhancing image contrast according to claim 11, characterized in that an alkali-soluble polymer is used as the base polymer of the polymer layer. 19. The method for enhancing image contrast according to claim 15, wherein in the two-layer resist structure, an alkali-soluble polymer is used as a base polymer for the upper layer and the lower layer. 20. A polymeric material containing a compound whose light transmittance is effectively improved by irradiation with light of 180 to 300 nm, which is used in the contrast enhancement method according to claim 11. 21. A resist material whose light transmittance is effectively improved by light irradiation, which is used in the method for enhancing image contrast according to claim 15.