JP2973874B2 - Pattern formation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention can form a wiring pattern with high processing accuracy and reliability by the lift-off method, and can be suitably used for forming a wiring pattern such as an aluminum electrode on a semiconductor. The present invention relates to a pattern forming method by a lift-off method.

[0002]

2. Description of the Related Art
When a wiring pattern such as an aluminum electrode is formed on a semiconductor, a process such as dry etching or wet etching has been used. The specific process is as shown in FIG. 3. After performing metal layer sputtering and resist patterning to form a resist pattern 3 on a metal layer 2 formed on a base 1, a resist pattern 3 is not formed. An etching process is performed on a part of the metal layer 2, and then the resist pattern 3 is stripped by a stripping solution to form a wiring pattern.

[0003] However, the above process has a problem in terms of processing accuracy and an etching operation when difficult-to-etch gold, tantalum, or the like is used as a metal layer (see VSLI manufacturing technology, Nikkei BP, 1989, p. 259). Therefore, in recent years, the lift-off method shown in FIG. 4 is often used. In the lift-off method, first, a resist pattern 3 is formed on the substrate 1 by resist patterning, and then a metal layer 2 is formed on the substrate 1 and the resist pattern 3 by metal layer sputtering, and the metal layer 2 is treated with a stripping solution. By removing the resist, a wiring pattern can be formed without an etching operation. As described above, the lift-off method is capable of forming a metal pattern using a precisely formed resist pattern as a mold, thereby enabling accurate processing, and if a hard-to-etch metal can be deposited on the base and the resist layer, Since there is no need for etching, there is an advantage that it can be easily processed. The resist stripping step plays an especially important role in this lift-off method. If the resist can be stripped efficiently so that no resist remains in this step,
By using the lift-off method, improvement in processing accuracy and reliability can be expected.

However, if a pattern is to be formed by the above-mentioned lift-off method using a general positive resist composition, the resist stripping step does not proceed well, or a resist residue is generated. At present, there is a problem in reliability and the like.

[0005] That is, the biggest problem in this case is FIG.
As shown in FIG. 5A, in the case of a positive resist, the resist pattern 3 becomes forward-tapered, so that metal sputtered particles having a certain degree of anisotropy come to the side wall of the resist pattern 3. (See FIG. 5-2), which may result in a possibility that the stripping solution cannot directly attack the resist pattern 3 in the next step of the resist stripping process. Further, even when the metal layer 2 attached to the side wall is thin and partially destroyed and the stripping solution permeates the resist pattern 3, the metal pattern 4 has an inverted tapered shape as shown in FIG.
Further, there is a possibility that burrs 5 may be generated and further a resist residue 6 may be generated.

On the other hand, in the field of positive photoresist,
A phenomenon called microgroove has been well known for some time (The 39th Federation of Applied Physics Related Lectures, Proceedings No. 2, p517, 29p-NA-15, 1992)
Year, spring). As shown by reference numeral 7 in FIGS. 1 and 2, the microgrooves are deformed at the bottom of the resist pattern, and have a shape in which the resist pattern 3 is hardly inserted into the inside at the interface with the substrate 1 and protrudes therefrom. It is. This phenomenon occurs because the photosensitizer disintegrates or disappears and dissolves at the bottom portion of the pattern, which should be an unexposed portion, and is considered to be caused by the photosensitizer concentration distribution.

[0007] If such a phenomenon occurs, for example, it is not used as a resist even if its resolution is excellent. Therefore, by controlling the solubility of the micro-grooved resist, the micro-groove can be controlled. Minimizing the occurrence was a major theme in the resist development field.

The present invention has been made in order to solve the above-mentioned problems in the lift-off method, and provides a method of forming a wiring pattern by the lift-off method, which can form a wiring pattern with high processing accuracy and high reliability. The purpose is to do.

[0009]

The present inventors have conducted intensive studies to achieve the above object, and as a result, (1) having a repeating unit represented by the following general formula (1) as an alkali-soluble resin, Polystyrene equivalent weight average molecular weight of 2
Novolak resin having a phenolic hydroxyl group as a dissolution promoter and having 2 to 5 benzene rings, represented by the following general formula (2) or (3): And (3) a photosensitizer represented by the following general formula (4)
Or a positive resist composition comprising a compound having a 1,2-naphthoquinonediazidosulfonyl group represented by (5) in a molecule and having an esterification rate of 65% or more, and particularly forming a resist film on a substrate. After forming, baking in a temperature range of 100 to 130 ° C. before exposure or development, exposure,
It has been found that it is effective in a pattern forming method by a lift-off method to form a resist pattern having microgrooves of a predetermined shape on a resist layer by developing.

[0010]

Embedded image (In the formula, m is an integer of 0 to 3.)

[0011]

Embedded image (Where j is 1 or 2, k, m and p are each 0 to 0)
3, n is 1 to 4, q is 1 to 3, r is an integer of 2 or 3,
m + p + n ≦ 6 and k + q ≦ 5. )

[0012]

Embedded image

That is, in the present invention, microgrooves, which have been disliked in the past, are positively expressed in the resist layer, and are intended to be applied particularly to the lift-off process which has been a problem in the conventional positive resist composition. It is. The process is as shown in FIG. 6. A resist pattern 3 having microgrooves 7 is formed on a substrate 1 by using the positive resist composition of the present invention, and metal sputtering or metal evaporation is performed on the resist pattern 3 to form a metal. Forming the layer 2 and stripping the resist can provide a number of advantages as described below. (1) There is no adhesion and deposition of metal to the microgroove portions generated at the bottom of the resist pattern, and the stripper can directly attack the resist pattern, and the resist can be stripped quickly and uniformly within a certain time. (2) The micro-groove portion generated at the bottom of the resist pattern exists as a void after metal deposition, and there is no remaining resist at the corner portion when the resist is stripped. (3) The finally obtained metal pattern can be a pattern having good rectangularity.

Therefore, according to the present invention, it is possible to form a wiring pattern having high processing accuracy and high reliability without the above-mentioned conventional problems in the lift-off method.

Accordingly, the present invention relates to the following: [A] After forming a resist pattern on a substrate, a metal layer is formed on the surface of the substrate including the resist pattern, and then the resist pattern is peeled off to form a predetermined metal on the substrate. A pattern forming method by a lift-off method comprising forming a pattern, wherein a micro-groove is formed in a resist layer constituting the resist pattern so as to satisfy the following condition A; In the resist layer profile shown in FIG.
When the line width of the resist layer is L μm, the thickness is T μm, the cut height of the micro groove is A μm, and the cut depth is B μm, the thickness T of the resist layer is 20 μm or less, and the degree of the cut of the micro groove is It is formed in the range of the above formulas [I] and [II]. [B] A resist pattern comprising: (1) a novolak resin having a repeating unit represented by the above general formula (1) as an alkali-soluble resin and having a polystyrene equivalent weight average molecular weight of 2,000 to 10,000, (2) a dissolution promoter A low nucleus represented by the above formula (2) or (3) having a phenolic hydroxyl group and having 2 to 5 benzene rings; (3) a photosensitizer represented by the above formula (4) or (4) The above pattern forming method comprising a positive resist composition for a lift-off method comprising a compound having a 1,2-naphthoquinonediazidosulfonyl group represented by 5) in a molecule and having an esterification rate of 65% or more, And [C] forming a resist film on the substrate with the above positive resist composition, performing baking in a temperature range of 100 to 130 ° C. before exposure or development, and then exposing, And an image, to provide the pattern forming method of forming the microgrooves to the resist layer.

[0016]

(Equation 2)

Hereinafter, the present invention will be described in more detail. The positive resist composition for a lift-off method according to the present invention comprises:
As the alkali-soluble resin, a novolak resin having a repeating unit represented by the following general formula (1) and having a polystyrene equivalent weight average molecular weight of 2,000 to 10,000 is used.

[0018]

Embedded image (In the formula, m is an integer of 0 to 3.)

The novolak resin of the above formula (1) is obtained by converting at least one of phenols represented by the following general formula (8), specifically, at least one of o-cresol, m-cresol, p-cresol, and an aldehyde. It can be synthesized by condensing by a usual method.

[0020]

Embedded image (In the formula, m is an integer of 0 to 3.)

In this case, the aldehydes include, for example, formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde, etc., but formaldehyde is preferred. In addition, the use ratio of the phenols and aldehydes of the above formula (8) is from 0.3 to
A ratio of 2 is preferred.

The average molecular weight of the alkali-soluble resin is as follows:
As described above, the weight average molecular weight in terms of polystyrene is 2
000 to 10,000, preferably in the range of 3,000 to 7,000. Polystyrene equivalent weight average molecular weight is 200
If it is smaller than 0, the heat resistance of the resist film does not reach a practical level, and if it exceeds 10,000, the resolution of the resist film is reduced.

Next, a low nucleus compound represented by the following general formula (2) or (3) having a phenolic hydroxyl group and having 2 to 5 benzene rings is blended as a dissolution accelerator. .

[0024]

Embedded image (Where j is 1 or 2, k, m and p are each 0 to 0)
3, n is 1 to 4, q is 1 to 3, r is an integer of 2 or 3,
m + p + n ≦ 6 and k + q ≦ 5. )

The number of benzene rings in the low nucleus is 2 to 5, and if it is less than 2, the heat resistance of the resist film is extremely deteriorated. If it exceeds 5, it becomes difficult to develop microgrooves. Specific examples of such low nuclei include the following.

[0026]

Embedded image

[0027]

Embedded image

[0028]

Embedded image

[0029]

Embedded image

[0030]

Embedded image

In the present invention, a 1,2-naphthoquinonediazidosulfonyl group represented by the following general formula (4) or (5) as a photosensitizing agent has an esterification ratio of 65% in the molecule.
The above compounds are blended.

[0032]

Embedded image

As the compound having a 1,2-naphthoquinonediazide group, for example, 1,2-quinonediazidosulfonyl chloride is represented by the following general formula (6) or (7):
And those obtained by introducing the compound into a ballast molecule represented by the following formula or trihydroxybenzophenone or tetrahydroxybenzophenone.

[0034]

Embedded image (Where j is 1 or 2, k, m and p are each 0 to 0)
3, n is 1 to 4, q is 1 to 3, r is an integer of 2 or 3,
m + p + n ≦ 6 and k + q ≦ 5. )

In this case, it is preferable to use a base-catalyzed dehydrochlorination condensation reaction of 1,2-naphthoquinonediazidosulfonyl chloride with a phenolic OH group as the introduction method, and the ballast molecules of formulas (6) and (7) are preferably used. Phenolic O of tri-, tri- or tetrahydroxybenzophenone
Those in which 65% or more of the H groups are substituted are preferably used.

As described above, the esterification rate of the compound having a 1,2-naphthoquinonediazidosulfonyl group is 65% or more, preferably 66 to 100%.
If it is less than the above, it becomes difficult to develop microgrooves.

In the positive resist composition of the present invention, the number of benzene rings having a phenolic hydroxyl group represented by the above formula (2) or (3) per 80 parts (parts by weight, hereinafter the same) of the alkali-soluble resin is used. Is 10 to 60
15 to 60 parts, especially 25 to 40 parts of a compound having a 1,2-naphthoquinonediazidosulfonyl group represented by the above formula (4) or (5) and having an esterification ratio of 65% or more, more preferably 20 to 40 parts. Is preferred. If the content of the low nucleus is less than 10 parts, it may be difficult to develop microgrooves, and if it exceeds 60 parts, the pattern may melt and flow. If the compounding amount of the compound having a 1,2-naphthoquinonediazidosulfonyl group is less than 15 parts, it may be difficult to develop microgrooves, and if it exceeds 60 parts, sensitivity is reduced and scum is remarkably generated. May be.

The method of forming a pattern by the lift-off method of the present invention comprises forming a resist film on a substrate using an appropriate resist composition, exposing and developing to form a desired resist pattern, and then performing vapor deposition, sputtering, etc. A metal layer such as gold or tantalum is formed on the surface of the base (on the resist pattern and on the part where the resist pattern is not formed) by a suitable method, and then the resist pattern is peeled off with a suitable peeling liquid. In the lift-off method of forming a predetermined metal pattern, a micro-groove is formed on a resist layer constituting the resist pattern, and after forming the metal layer on the resist pattern having the micro-groove as described above, the micro-groove is formed. The resist pattern is peeled off.

In this case, the microgrooves are shown in FIGS.
Can be formed in a shape such as a square groove or a triangular groove as shown in FIG. 1, and its size is determined by the line width of the resist layer 3 in the resist layer profile shown in FIG. 1 or FIG.
m, the thickness is T μm, the cut height of the micro groove 7 is A μm, and the cut depth is B μm, the thickness T of the resist layer 3 is 20 μm or less, and the degree of the cut of the micro groove 7 is expressed by the following formula [ I] and [II],
More preferably, it is preferable to form in the range of [I '] and [II'].

[0040]

(Equation 3)

If the A / T is smaller than 1/20, the cut is small and the effect in the peeling-off process of the lift-off method may be reduced. If the A / T is larger than 2/5, the pattern may be easily broken or flown from the root. Cases arise. On the other hand, A
If / B is smaller than 1/10, the adhesion to the substrate is poor, and the pattern is more likely to flow out. If it is larger than 2, metal is more likely to adhere to the cut portions, making it difficult to remove the resist after the metal attaching step. There are cases.

Here, the resist composition may be any one as long as it can form the microgroove as described above. In particular, the positive resist composition for lift-off according to the present invention described above is used. The use of this resist composition makes it possible to effectively form the above microgrooves.
That is, in the related art, the positive resist composition has been repelled as a substance that generates microgrooves. On the contrary, in the present invention, the resist composition is effectively used.

When the positive resist composition of the present invention is used, it is particularly effective to bake at a temperature of 100 to 130 ° C. after forming a resist film and before exposure or development, whereby the microgrooves are formed. It can be generated more effectively. The baking of the resist film is
It can be performed at any stage of the pre-bake step or the post-exposure bake step. Here, if the baking temperature is lower than 100 ° C., microgrooves do not occur, and if the baking temperature exceeds 130 ° C., the resist may be difficult to peel. A more preferred bake temperature is 100-120
° C.

[0044]

According to the present invention, a wiring pattern with high processing accuracy and high reliability can be formed by the lift-off method.

[0045]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Synthesis Examples, Examples, and Comparative Examples, but the present invention is not limited to the following Examples. In the following, all parts are parts by weight.

In each example, the evaluation of various resist properties was performed by the following methods. (1) weight average molecular weight Mw Toyo Soda Co. GPC column of the alkali-soluble resin (G2000H ₆ 2 present, G
Using 3000H _{6 (} 3 pieces, G4000H ₆ 1 piece), a flow rate of 1.5 ml / min, an eluting solvent of tetrahydrofuran, and a column temperature of 40 ° C. were analyzed by a GPC method using monodisperse polystyrene as a standard. (2) Alkali solubility of alkali-soluble resin The alkali-soluble resin was dissolved in an ECA solvent with a solid content of 35%, and applied to a 6 ″ Si wafer by 2,000 times.
Bake on a hot plate at 0 ° C for 90 minutes.
A resin film having a thickness of μm was obtained. This was applied to a development process monitor (PMS-601) manufactured by Dainippon Screen Co., Ltd.
After developing with 38% tetramethylammonium hydroxide (TMAH), the time until the residual film becomes zero is measured, and the initial film thickness is divided by the time when the residual film becomes zero, and the alkali solubility is calculated as on-gloom / sec. (Å / sec). (3) Esterification Rate The molecular weight per phenolic OH group of the compound represented by the above general formula (6) or (7) (the molecular weight of the compound is 1
Value divided by the number of OH groups in the molecule) is defined as the OH value,
Considering this OH value as a hypothetical molecular weight per OH group,
The ratio of the 1,2-quinodiazide sulfonyl group introduced here was defined as the ratio in terms of the number of moles at the time of charging. (4) Resist film thickness Spin coater (SKW-636) manufactured by Dainippon Screen Co., Ltd.
-BV), the prepared resist composition was applied on an HMDS-treated Si wafer, and soft-baked on a hot plate at 90 ° C. for 90 minutes.
The resist film thickness was measured with 210 (trade name: optical film thickness measuring device). (5) Optimal exposure dose Eop Nikon i-line (365 nm) exposure apparatus X / SR-17
Exposure was performed by changing the exposure time with 55i7A (numerical aperture of the lens: NA = 0.50), and a paddle at 23 ° C. for 65 seconds using a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH) as a developer. After development and rinsing with pure water, spin drying was performed. Next, 1 electron microscope (S-4100) manufactured by Hitachi, Ltd.
The exposure energy when a 0 μm line and space pattern is formed in a width of a ratio of 1: 1 is set to an optimum exposure amount Eo.
It was defined as p (sensitivity) and determined.

Synthesis Example 1 Synthesis of Alkali-Soluble Resin 64.9 g (0.60 mol) of p-cresol was placed in a three-necked flask equipped with a stirrer, a condenser, and a thermometer.
43.3 g (0.40 mol) of cresol, 44.6 g (0.55 mol) of a 37% by weight aqueous formaldehyde solution and 0.30 g (2.4 g of oxalic acid dihydrate as a polycondensation catalyst)
× 10 ^-3 mol), the flask was immersed in an oil bath, the internal temperature was maintained at 100 ° C, and polycondensation was performed for 1 hour.

After completion of the reaction, 500 ml of MIBK (methyl isobutyl ketone) was added, and the mixture was stirred for 30 minutes. Then, the aqueous layer was separated, and the product extracted into the MIBK layer was removed by 300 m.
After washing with water 5 times with 1 l of pure water and separating the solution, a reduced pressure strip at 150 ° C. was performed at 4 mmHg by an evaporator. As a result, 87 g of the novolak resin A-1 could be recovered.

Further, as shown in Table 1, using the starting phenols and formaldehyde, the synthesis was carried out in the same manner as for the novolak resin A-1.
2 to 4 were obtained.

[0050]

[Table 1]

[Synthesis Example 2] Synthesis of 1,2-quinodiazide compound In a flask equipped with a stirrer, a dropping funnel and a thermometer under light shielding, 10.0 g (119 mmol) of the resorcinol derivative shown in Table 2 and 1,2-naphtho 24.0 g (89.2 mmol) of quinonediazide-4-sulfonyl chloride was added to 20
Dissolved in 0 g of 1,4-dioxane. 25 flasks
Immersion in a water bath, and 10.50 g of 1,4-diazabicyclo [2,2,2] octane (DABCO) in 1,4-dioxane
The catalyst dissolved in 0 g was added dropwise using a dropping funnel. Thereafter, the precipitated DABCO hydrochloride was removed by filtration,
The filtrate was added dropwise to 1800 g of 0.12 N hydrochloric acid solution with stirring to reprecipitate. This was further filtered, and the reprecipitate was removed for 30 minutes.
The mixture was extracted into 0 ml of ethyl acetate, and washed and separated with 100 g of pure water five times. This was further stripped at 40 ° C. or lower using an evaporator to obtain 26 g of a 1,2-quinonediazide compound B-1.

Further, using the resorcinol derivative and 1,2-naphthoquinonediazidosulfonyl chloride shown in Table 2, it was synthesized in the same manner as in the above 1,2-quinonediazide compound B-1. The quinonediazide compound B-2,3 was obtained.

[0053]

[Table 2]

Examples 1 to 10 A 1,2-quinonediazide compound, a dissolution promoter and a solvent were added to 80 parts of an alkali-soluble resin shown in Table 3 and mixed as shown in Table 3 to obtain a uniform solution. Thereafter, the solution was filtered through a membrane filter having a pore size of 0.2 μm to prepare a positive resist composition solution.

The obtained resist solution was applied on a 6 ″ silicon wafer, and soft-baked at 90 ° C. for 90 seconds to form a resist film having a thickness of 3.0 μm.

Next, a wavelength of 365 nm is passed through a reticle.
Irradiation of (i-line), PE at 120 ° C. × 90 seconds
After performing B (post exposure baking)
Development, rinsing with pure water, and drying were performed. The performance of the obtained resist was evaluated by the method described above, and the pattern profile of 10 μmL / S was evaluated based on the cut depth (height A, depth B) of the micro groove shown in FIGS. Table 3 shows the results.

From the results shown in Table 3, it was confirmed that when a pattern was formed using the positive resist composition of the present invention, microgrooves were positively generated, and a resist pattern having high processing accuracy and high reliability could be formed. Was.

[0058]

[Table 3]

[Examples 11 to 20] Examples 11 to 20 were carried out using a vacuum deposition apparatus (EVD-500) manufactured by Nidec Anelva.
Au was formed to a thickness of 5000 mm on the pattern formed in step 0, and then immersed in an acetone solvent for 15 minutes to remove the resist. The remaining Au pattern was observed with an electron microscope to confirm the presence of the resist residue and the presence of Au burrs. As a result, there was no resist residue and no Au burrs occurred.

[Comparative Examples 1-4] Alkali-soluble resin 80
Parts, a 1,2-quinonediazide compound, a dissolution promoter and a solvent were added and mixed as shown in Table 4 to form a uniform solution, which was then filtered through a membrane filter having a pore size of 0.2 μm to obtain a positive resist composition. Was prepared.

The obtained resist solution was applied on a 6 ″ silicon wafer, and soft-baked at 90 ° C. for 90 seconds to form a resist film having a thickness of 3.0 μm.

Next, a wavelength of 365 nm is passed through a reticle.
Irradiation of (i-line), PE at 120 ° C. × 90 seconds
After performing B, development, rinsing with pure water, and drying were performed. The performance of the obtained resist was evaluated by the above method, and
When the pattern profile of mL / S was evaluated, none of the microgroove cuts shown in FIGS.

Then, Au was formed to a thickness of 5000 mm on the obtained pattern by using a vacuum evaporation apparatus EVD-500, and then immersed in an acetone solvent for 15 minutes to remove the resist. The results are shown in Table 4, and the results were poor because the resist could not be stripped, or the resist remained even after the resist could be stripped.

[0064]

[Table 4]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of a resist layer on which microgrooves are formed.

FIG. 2 is a cross-sectional view illustrating another example of a resist layer on which microgrooves are formed.

FIG. 3 is a schematic diagram showing an etching process.

FIG. 4 is a schematic view showing a method of forming a resist pattern by a lift-off method.

FIG. 5 is a schematic view showing a state in which a resist pattern is formed by a lift-off method using a conventional positive resist composition.

FIG. 6 is a schematic view showing a state in which a resist pattern is formed by a lift-off method using the positive resist composition of the present invention.

[Explanation of symbols]

 1 base 2 metal layer 3 resist pattern 4 metal pattern 7 micro groove

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI H01L 21/3205 H01L 21/88 G (72) Inventor Yu Yu Kobayashi 1-chome, Matsuida-cho, Usui-gun, Gunma Prefecture 10 Shin-Etsu Chemical Co., Ltd. (72) Inventor Miki Kobayashi Miki Kobayashi 1-10 Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture Shin-Etsu Chemical Co., Ltd.Silicon Electronics Material Research Laboratory (72) Mitsuo Umemura Usui-gun, Gunma Prefecture Shin-Etsu Chemical Industry Co., Ltd. Silicone Electronic Materials Technology Research Laboratory (72) Inventor Toshinobu Ishihara 28-1 Nishifukushima, Nishi-Juku-mura, Nakakubiki-gun, Niigata Prefecture Shin-Etsu Chemical Industry Co., Ltd. 56) References JP-A-6-67418 (JP, A) JP-A-4-299348 (JP, A) JP-A-4-11260 JP, A) JP-A-3-230164 (JP, A) JP-A-6-59445 (JP, A) JP-A-5-204143 (JP, A) JP-A-4-122938 (JP, A) JP JP-A-5-323605 (JP, A) JP-A-2-10350 (JP, A) JP-A-3-236216 (JP, A) JP-B-3-35654 (JP, B2) (58) Fields surveyed (Int .Cl. ⁶ , DB name) G03F 7/26 G03F 7/004 G03F 7/022 G03F 7/023 H01L 21/027 H01L 21/3205

Claims (5)

(57) [Claims] After a resist pattern is formed on a substrate, a metal layer is formed on the surface of the substrate including the resist pattern, and then the resist pattern is peeled off to form a predetermined metal pattern on the substrate. A pattern forming method according to a lift-off method, wherein microgrooves are formed in a resist layer constituting the resist pattern so as to satisfy the following condition A. Condition A In the resist layer profile shown in FIG. 1 or FIG.
When the line width of the resist layer is L μm, the thickness is T μm, the cut height of the micro groove is A μm, and the cut depth is B μm, the thickness T of the resist layer is 20 μm or less, and the degree of the cut of the micro groove is The following formulas [I] and [II] Formed in the range. 2. A resist pattern comprising: (1) a novolak resin having a repeating unit represented by the following general formula (1) as an alkali-soluble resin and having a polystyrene equivalent weight average molecular weight of 2,000 to 10,000: (Where m is an integer of 0 to 3.) (2) The following general formula (2) or (2) having a phenolic hydroxyl group as a dissolution promoter and having 2 to 5 benzene rings. The low nucleolus represented by 3) (Where j is 1 or 2, k, m and p are each 0 to 0)
3, n is 1 to 4, q is 1 to 3, r is an integer of 2 or 3,
m + p + n ≦ 6 and k + q ≦ 5. (3) A compound having a 1,2-naphthoquinonediazidosulfonyl group represented by the following general formula (4) or (5) as a photosensitizer in a molecule and having an esterification rate of 65% or more: The pattern forming method according to claim 1, wherein the pattern forming method is performed using a positive resist composition for a lift-off method, which comprises: 3. A 1,2-quinonediazidosulfonyl chloride compound represented by the following general formula (6):
3. The pattern forming method according to claim 2, wherein a material obtained by introducing into the ballast molecule represented by (7) or trihydroxybenzophenone or tetrahydroxybenzophenone is used. Embedded image (Where j is 1 or 2, k, m and p are each 0 to 0)
3, n is 1 to 4, q is 1 to 3, r is an integer of 2 or 3,
m + p + n ≦ 6 and k + q ≦ 5. ) 4. The amount of the component (1) is 80 parts by weight,
4. The pattern forming method according to claim 2, wherein the amount of the component (2) is 10 to 60 parts by weight, and the amount of the component (3) is 15 to 60 parts by weight. 5. A resist film is formed on a substrate with a positive resist composition, and is exposed to a temperature of 100 to 130 ° C. before exposure or development.
5. The pattern forming method according to claim 2, wherein the baking is performed in the temperature range described above, followed by exposure and development to form microgrooves in the resist layer.