JPH07128865A - Developer composition for resist - Google Patents

Abstract

PURPOSE:To obtain a satisfactory resist pattern and to improve the defoamability of a developer for a resist after development by adding a compd. such as polyoxypropylene monoalkyl ether to the developer. CONSTITUTION:At least one kind of compd. selected from polyoxy-propylene monoalkyl ether, polypropylene glycol and polyoxyethylene monoalkyl ether is added to a developer for a resist contg. a metal ion-free org. base as an essential agent. Commercially available surfactants may be used as the polyoxypropylene monoalkyl ether, polypropylene glycol and polyoxyethylene monoalkyl ether. Additives used in a conventional developer for a resist, e.g. known various surfactants, lubricants, stabilizing agents and dissolving aids may properly be added if the purpose is attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist developer composition used in the production of semiconductor devices such as ICs and LSIs, liquid crystal devices and the like. More specifically, it provides an excellent resist pattern shape and resist composition. The present invention relates to a resist developer composition capable of extremely suppressing foaming of a developer after development, that is, in other words, having extremely excellent defoaming property.

[0002]

2. Description of the Related Art Conventionally, in the manufacture of semiconductor devices, liquid crystal devices, etc.
When etching or diffusion treatment is performed, the following treatment is generally performed for the purpose of selectively protecting the underlying substrate. That is, ultraviolet rays, far ultraviolet rays, excimer lasers,
A material that is sensitive to actinic radiation such as X-rays and electron beams.
A so-called radiation-sensitive resist is formed on a substrate to form a film, which is then imagewise exposed and developed to form an image, which is used as a protective layer. In lithography using a radiation-sensitive resist containing an alkali-soluble resin as a film-forming component of such a radiation-sensitive resist, an alkaline aqueous solution is generally used as a developing solution.

When a semiconductor device or a liquid crystal device is manufactured, the use of an alkaline aqueous solution containing metal ions adversely affects the obtained device characteristics. Therefore, metal-ion-free developers, such as tetramethylammonium hydroxide (IBM Technical Di
Sclosure Bulletin Vol. 3, No. 7, 2009, 1970) and trimethyl (2-hydroxyethyl) ammonium hydroxide [choline (US Pat. No. 4,
239661)] and the like.

A developing solution using such an aqueous solution of tetramethylammonium hydroxide (hereinafter simply abbreviated as TMAH) or choline is easier to store and treat as a waste solution than other developing solutions using an organic solvent. Moreover, since it is nonflammable, no special safety measures are required, and it can be said that it is a highly versatile developer.

[0005]

However, when such a versatile developer is used a plurality of times without replacement even after the development processing, air is usually entrained in the developer and bubbles are generated. Further, the resist component is also dissolved in the developing solution, and this resist component prevents defoaming of bubbles and promotes accumulation of bubbles. As a result, the accumulation of bubbles has caused the inconvenience that the circulation of the developing solution and the visual confirmation of the developing solution amount are hindered.

The present invention was devised under such circumstances, and its purpose is to obtain a good resist pattern shape and the like and to obtain excellent resist characteristics, and also to use a developing solution a plurality of times. It is an object of the present invention to provide a resist developer composition which does not cause foaming even when used, in other words, is excellent in so-called defoaming property.

[0007]

In order to achieve such an object, the present invention provides a resist developing solution containing a metal ion-free organic base as a main component, polyoxypropylene monoalkyl ether, polypropylene glycol and At least one selected from polyoxyethylene monoalkyl ether was added.

The present invention having such a structure will be described in detail below.

As the organic base containing no metal ions, which constitutes the main component of the developing solution, those generally known as developing solutions for resists which can be developed with alkali can be used as they are. Examples of such a compound include, for example, arylalkylamines having a linear, branched or cyclic primary or secondary tertiary amine substituent, specifically 1,
Alkylenediamine such as 3-diaminopropane, 4,
Arylamines such as 4'-diaminodiphenylamine, amines such as n, n'-diaminodialkylamine, 3 to 5 carbon atoms in the ring skeleton, and 1 or 2 heteroatoms selected from nitrogen and oxygen sulfur. A heterocyclic base having and, for example, pyrrole, pyrrolidine, pyrrolidone,
Pyridine, morpholine, pyrazine, piperidine, oxazole, thiazole and the like can be mentioned. Also, lower alkyl quaternary ammonium bases and the like are used. Specific examples thereof include TMAH, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, trimethylethylammonium hydroxide, trimethyl (2-hydroxyethyl) ammonium hydroxide (choline), triethyl (2-hydroxyethyl).
Examples thereof include ammonium hydroxide, tripropyl (2-hydroxyethyl) ammonium hydroxide, trimethyl (1-hydroxypropyl) ammonium hydroxide. Among these, lower quaternary ammonium bases are preferable, and TMAH and trimethyl (2-hydroxyethyl) ammonium hydroxide (choline) are particularly preferable. These organic bases containing no metal ion may be used alone or in combination of two or more kinds.

As for the organic base containing no metal ion, which constitutes the main component of the developer as described above, an appropriate concentration is selected depending on the type of organic base used and the resist. -10% by weight, preferably
It is adjusted in the concentration range of 2 to 5% by weight. If this value is less than 1% by weight, the development cannot be performed sufficiently and the resist pattern is not formed.
If it exceeds 0% by weight, the film loss in the unexposed area becomes large,
There is a disadvantage that a good resist pattern cannot be formed.

In the present invention, the resist developer containing an organic base containing no metal ion as a main component is selected from polyoxypropylene monoalkyl ether, polypropylene glycol and polyoxyethylene monoalkyl ether. At least one is added.

The polyoxypropylene monoalkyl ether as the first component that can be added is a compound represented by the following general formula [I].

H- (OC ₃ H ₆ ) _n —OR ¹ [I] Here, R ¹ represents an alkyl group having 1 to 20 carbon atoms, and n
Represents an integer of 2 to 100.

Specific examples of R ¹ include methyl group, ethyl group, propyl group, butyl group, octyl group, nonyl group, lauryl group and cetyl group. Of these, a lower alkyl group having 5 or less carbon atoms is preferable, and a methyl group is more preferable. The larger the number of carbon atoms in R ^1, the worse the solubility in the developer, and
This is because the defoaming property of the developer after the development processing is also inferior.

As described above, n is an integer in the range of 2 to 100, and the average molecular weight of the compound is 100 to 580.
It may be in the range of 0, but in view of the solubility in the developing solution and the defoaming cloud point of the developing solution after the development treatment, it is preferable n.
The range is 20 (average molecular weight 1200) or less, particularly 2 to 20 (average molecular weight 100 to 120).
0), more preferably n is 14 (average molecular weight is 900) or less, and particularly 4 to 14 (average molecular weight is
300-900). Generally, when the cloudiness seen in the nonionic surfactant occurs, the development process cannot be performed and the resist pattern cannot be formed. Therefore, it is important that the cloudiness does not occur during the storage of the developer or the development process. A higher cloud point is preferable.

Polypropylene glycol as the second component that can be added is a compound represented by the following general formula [II].

H- (OC ₃ H ₆ ) _n- OH ... [II] Here, n represents an integer of 2 to 18. Converting the range of n = 2 to 18 into the average molecular weight, the average molecular weight is 100 to 10.
The average molecular weight is 300 to 800.
Is preferred. When the value of the average molecular weight is less than 100, the desired defoaming property is insufficient. On the other hand, when the value of the average molecular weight exceeds 1000, there is a disadvantage that a good resist pattern cannot be obtained.

The polyoxyethylene monoalkyl ether as a third component which can be added is represented by the following general formula [I
II]].

H- (OC ₂ H ₄ ) _n —OR ² ... [III] Here, R ² represents an alkyl group having 5 to 10 carbon atoms, and n
Represents an integer in the range of 2 to 12.

Specific examples of R ² include amyl group (pentyl group), hexyl group, heptyl group, octyl group, nonyl group and decyl group. Such carbon number 5-10
By using the polyoxyethylene monoalkyl ether having an alkyl group, the solubility in the developing solution becomes extremely good, and the defoaming property of the developing solution after the development processing becomes extremely good.

N is an integer in the range of 2 to 12, and the average molecular weight of the compound must be in the range of 100 to 500. When the value of the average molecular weight is less than 100, the desired defoaming property becomes insufficient, while when the value of the average molecular weight exceeds 500, there is a disadvantage that a good resist pattern cannot be obtained.

As described above, the compounding amounts of the polyoxypropylene monoalkyl ether, polypropylene glycol and polyoxyethylene monoalkyl ether used in the present invention are appropriately selected depending on the organic base as the main agent and the resist composition. But in general,
It is adjusted within a concentration range of 100 to 4000 ppm, preferably 200 to 2500 ppm, with respect to a resist developing solution containing an organic base containing no metal ion as a main component.
If this value is less than 100 ppm, the defoaming effect is not sufficiently exhibited, and if it exceeds 4000 ppm, the resist pattern shape is rounded or trapezoidal, and a good resist pattern cannot be obtained. Inconvenience occurs.

In the present invention, of course, two or more kinds selected from polyoxypropylene monoalkyl ether, polypropylene glycol and polyoxyethylene monoalkyl ether may be used in combination at the same time. In that case, two or more kinds of additives are added. The total concentration may be adjusted so as to satisfy the above concentration range.

Commercially available surfactants can be used for the polyoxypropylene monoalkyl ether, polypropylene glycol and polyoxyethylene monoalkyl ether added in the present invention.

The resist developer composition of the present invention is an additive component conventionally used in resist developers, such as various known surfactants, within a range that does not impair the object of the present invention. Lubricants, stabilizers, dissolution aids, etc. may be added as appropriate.

The resist to be developed by the resist developing solution composition of the present invention as described above may be any of negative type and positive type as long as it can be developed using an alkaline aqueous solution. Such a resist can also be used. Specific resists include, for example, a positive resist containing a naphthoquinonediazide compound and a novolac resin, a compound that generates an acid upon exposure, a compound that decomposes with an acid to increase its solubility in an alkaline aqueous solution, and an alkali-soluble resin. Positive resist, compound generating an acid upon exposure, positive resist containing an alkali-soluble resin having a group which is decomposed by an acid and has increased solubility in an alkaline aqueous solution, compound generating an acid upon exposure, crosslinking agent, alkali Examples include negative resists containing a soluble resin, but the present invention is not limited to these.

Next, an example of a method of using the resist developer composition of the present invention will be described. First, a resist layer is first formed on a substrate such as a silicon wafer or glass. Next, a light source that emits active rays such as ultraviolet rays, far ultraviolet rays, excimer lasers, X-rays, and electron beams, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp,
The resist layer is exposed through a desired mask pattern using an arc lamp, a xenon lamp, or the like, or the resist layer is irradiated while scanning an electron beam. Then, if necessary, a post-exposure heat treatment (post exposure bake) is performed, and then pattern development is performed using a resist developing solution. That is, the substrate coated with the resist is dipped in a developing solution for a certain period of time, followed by immersion development in which it is washed with water and dried, and the developing solution is dropped on the surface of the coated resist and left standing for a certain period of time and then washed with water to be paddle developed Various developments suitable for the purpose, such as spray development in which a developing solution is sprayed on the resist surface and then washed with water and dried, are performed, and then a predetermined resist pattern can be obtained.

[0028]

EXAMPLES The present invention will be described in more detail with reference to specific examples.

First, the following 21 kinds of additives (activators (A-1) to (A-
9), (B-1) to (B-3), (C-1) to (C-
2), (D-1) to (D-7)) were prepared. (1) (A-1): R ¹ of the above formula [I] is CH ₃ polyoxypropylene methyl ether, average molecular weight = 4
00 (2) (A-2): R ¹ of the above formula [I] is C ₄ H ₉ polyoxypropylene butyl ether, average molecular weight = 2
00 (3) (A-3): R ¹ of the above formula [I] is CH ₃ polyoxypropylene methyl ether, average molecular weight = 2
00 (4) (A-4): R ¹ of the above formula [I] is C ₃ H ₇ , polyoxypropylene propyl ether, average molecular weight =
300 (5) (A-5): R ¹ of the above formula [I] is CH ₃ polyoxypropylene methyl ether, average molecular weight = 6
00 (6) (A-6): R ¹ of the above formula [I] is C ₂ H ₅ polyoxypropylene ethyl ether, average molecular weight = 2
00 (7) (A-7): R ¹ of the above formula [I] is C ₂ H ₅ polyoxypropylene ethyl ether, average molecular weight = 4
00 (8) (A-8): R ¹ of the above formula [I] is C ₅ H ₁₁ polyoxypropylene pentyl ether, average molecular weight =
400 (9) (A-9): R ¹ of the above formula [I] is CH ₃ polyoxypropylene methyl ether, average molecular weight = 1
000 (10) (B-1): polypropylene glycol of the above formula [II], average molecular weight = 400 (11) (B-2): polypropylene glycol of the above formula [II], average molecular weight = 700 (12) (B -3): Polypropylene glycol of the above formula [II], average molecular weight = 500 (13) (C-1): R ² of the above formula [III] with C ₅ H ₁₁ polyoxyethylene monoamyl ether, average Molecular weight =
300 (14) (C-2): R ² of the above formula [III] is C ₈ H ₁₇ polyoxyethylene monooctyl ether, average molecular weight = 200 (15) (D-1): ethylene oxide propylene oxide block Copolymer (Ethyleneoxy group / Propyleneoxy group = 15/8
5) Average molecular weight = 1000 (nonionic surfactant) (16) (D-2): ethylene oxide propylene oxide block copolymer (ethyleneoxy group / propyleneoxy group = 15/8
5) Average molecular weight = 3000 (nonionic surfactant) (17) (D-3): ethylene oxide propylene oxide block copolymer (ethyleneoxy group / propyleneoxy group = 10/9
0) Average molecular weight = 2500 (nonionic surfactant) (18) (D-4): ethylene oxide propylene oxide block copolymer (ethyleneoxy group / propyleneoxy group = 10/9
0) Average molecular weight = 5900 (nonionic surfactant) (19) (D-5): nonionic acetylene alcohol surfactant, Surfynol 82 (20) (D-6): the following structure Nonionic surfactant represented by the formula

[0030]

[Chemical 1] (21) (D-7): tributylmethylammonium chloride (cationic surfactant) As the next step, tetramethylammonium hydroxide (TMA) was used as an organic base containing no metal ion.
H) was prepared and this was dissolved in water to obtain a 2.38 wt% TMAH aqueous solution. The above-mentioned various activators were added to this aqueous solution to prepare resist developer compositions of Examples 1 to 17 and Comparative Examples 1 to 7 as shown in Table 1 below.

[0031]

[Table 1] With respect to each of the various resist developer compositions thus prepared, the solubility, cloud point, defoaming property, and pattern shape were evaluated as described below. Evaluation item (1) Solubility Regarding the solubility, various activators shown in Table 1 were added as 4000 ppm to the 2.38 wt% TMAH aqueous solution which was usually used as a developing solution and kept at 23 ° C. Solubility was shown when it was added so that. The evaluation criteria at that time are as follows.

◯: Immediately dissolved Δ: Some time required for dissolution ×: Not dissolved (2) Cloud point Various resist developer compositions shown in Table 1 were used at 40 ° C.
The presence or absence of cloudiness at this temperature was determined. The evaluation criteria are as follows.

○: No fog was generated ×: Fog was generated (3) Defoaming property After coating various resist compositions shown in Table 2 on a 6-inch silicon wafer and drying, a desired pattern was formed. After irradiation with actinic rays through a mask and subsequent development treatment with various resist developer compositions shown in Table 1, the defoaming properties of the developers were examined. That is, in order to accelerate the amount of bubbles generated by the developing process, the developing solution on which each of the 10 developing processes was performed was vibrated. Subsequently, the time required for the bubbles to disappear was examined. The evaluation criteria at that time are as follows.

∘: Complete disappearance of bubbles within 1 minute ∘: Complete disappearance of bubbles within 10 minutes X: It took more than 10 minutes for disappearance of bubbles. When each was developed using the developer corresponding to (1), the tendency of causing uneven development was remarkable in the case of ×, as compared with the cases of ⊚ and ○, as the number of processed sheets increased. (4) Pattern shape Each of the resist compositions shown in Table 2 was coated on a 6-inch silicon wafer, dried, and then irradiated with an actinic ray through a mask having a desired pattern. The resist pattern obtained by developing with the various resist developer compositions described above was observed by an SEM (scanning electron microscope) photograph to evaluate the pattern shape. The evaluation criteria are as follows.

Good: The resist pattern has a substantially rectangular shape. Poor: The top has a round shape. The evaluation results are shown in Table 2 below.

[0036]

[Table 2] In Table 2, there are three types of resist compositions for forming resist patterns ((R-1) to
(R-3)), and the details thereof are as follows. -(R-1): trade name TFR-B2, a positive resist containing a naphthoquinonediazide compound and a novolak resin- (R-2): trade name THMR-iN200, a negative containing an acid generator, a cross-linking agent, and an alkali-soluble resin. Type resist- (R-3): positive type resist containing trade name TDUR-P, acid generator, and alkali-soluble resin (all of these are manufactured by Tokyo Ohka Kogyo Co., Ltd.)

[0037]

As described in detail above, according to the present invention,
At least one selected from polyoxypropylene glycol monoalkyl ether, polypropylene glycol and polyoxyethylene monoalkyl ether,
Since a conventionally used organic base containing no metal ion is added to a resist developer containing a base as a main component, a good resist pattern can be obtained and a resist excellent in defoaming property of the developer after development processing. A developer composition for use can be obtained. Due to the excellent defoaming property, the circulation of the developing solution becomes smooth, and the amount of the developing solution can be visually checked easily, so that the developing solution can be easily replenished.

Claims (8)

[Claims] 1. A developer for a resist containing an organic base containing no metal ions as a main component, to which at least one selected from polyoxypropylene monoalkyl ether, polypropylene glycol and polyoxyethylene monoalkyl ether is added. A developer composition for a resist, which is characterized. 2. The resist developer composition according to claim 1, wherein the alkyl group of the polyoxypropylene monoalkyl ether is a lower alkyl group. 3. The polyoxypropylene monoalkyl ether is 100 to 4000 pp relative to a resist developing solution containing an organic base containing no metal ion as a main component.
m is contained, Claim 1 or Claim 2 characterized by the above-mentioned.
The developer composition for a resist according to item 1. 4. The resist developer composition according to claim 1, wherein the polypropylene glycol has an average molecular weight of 100 to 1,000. 5. The polypropylene glycol is contained in an amount of 100 to 4000 ppm with respect to a resist developing solution containing an organic base containing no metal ions as a main component. A resist developer composition. 6. The resist developer composition according to claim 1, wherein the polyoxyethylene monoalkyl ether has an average molecular weight of 100 to 500. 7. The resist developer composition according to claim 1, wherein the alkyl group of the polyoxyethylene monoalkyl ether is an alkyl group having 5 to 10 carbon atoms. 8. The polyoxyethylene monoalkyl ether is 100 to 4000 ppm with respect to a resist developing solution containing an organic base containing no metal ions as a main component.
The resist developer composition according to claim 1, wherein the resist developer composition is contained.