JP2005115373A - Thinner composition for removing photoresist - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thinner composition for removing a photoresist to efficiently remove an unnecessary photoresist in a short period of time which is deposited on edges and back faces of a glass substrate to be used for a liquid crystal display device or of a wafer to be used for manufacturing a semiconductor. <P>SOLUTION: The thinner composition for removing a photoresist contains (a) propyleneglycol monoalkylether acetate, (b) alkyl ethanoate and (c) alkyl lactate. The thinner obtained by using the above thinner composition efficiently removes in a short period of time an unnecessary photoresist deposited on edges and back faces of a glass substrate to be used for a liquid crystal display device or of a wafer to be used for manufacturing a semiconductor, the thinner also has high stability and safeness for a human body and is applicable for various processes. Consequently, the manufacturing processes of a liquid crystal display device and a semiconductor are simplified and the production yield can be economically improved. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a thinner composition for removing a photoresist. More specifically, not only the glass substrate used in the liquid crystal display device and the unnecessary photoresist adhering to the edge and the rear surface portion of the wafer used in the semiconductor manufacturing can be efficiently removed in a short time, but also to the human body. The present invention relates to a thinner composition for removing a photoresist that has high stability and can be applied to various processes, can simplify a liquid crystal display device and a semiconductor manufacturing process, and can economically improve a production yield.

  During the semiconductor manufacturing process, a photolithography process is performed by applying a photoresist to the wafer surface, transferring a pattern as designed in advance, and etching a predetermined portion by the transferred and developed wafer pattern. This is an operation of constructing an electronic circuit and is one of the extremely important operations.

Such a photolithography process is
(1) A process of uniformly applying a photoresist to the wafer surface,
(2) a soft baking process in which the solvent is evaporated from the applied photoresist so that the photoresist adheres to the surface of the wafer;
(3) An exposure process in which a circuit pattern on a mask is sequentially and repeatedly reduced and projected using a light source such as ultraviolet light to expose the wafer and transfer the mask pattern onto the wafer.
(4) a development process for selectively removing, using a developer, a part having different physical properties such as a difference in solubility due to exposure to light source;
(5) a hard baking process for closer adhesion of the photoresist remaining on the wafer after development to the wafer;
(6) an etching process for etching a predetermined portion in order to impart electrical characteristics depending on the pattern of the developed wafer; and
(7) A stripping step for removing the photoresist that is no longer necessary after the step,
It can be divided roughly.

  Among such photolithography processes, after the soft baking process of the above (2), there may be unnecessary photoresist applied to the edge portion and the back surface of the wafer, but due to their presence, Various problems occur in subsequent processes such as etching, ion implantation, and the like, and there is a problem that the overall yield of the semiconductor device is reduced. Therefore, it is necessary to remove these defects.

  Conventionally, in order to remove unnecessary photoresist existing on the edge and back surface of a wafer, there is a method in which spray nozzles are installed above and below the wafer edge portion, and a thinner composed of an organic solvent component is sprayed on the edge and back surface through the nozzle. It has been mainly used.

  Conventionally, as thinner compositions, ethers and ether acetates such as cellosolve, cellosolve acetate, propylene glycol ether, propylene glycol ether acetate, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl lactate, ethyl lactate, methyl acetate Thinner compositions using ethers such as ethyl acetate and butyl acetate are known, and a method of removing them by bringing them into contact with unnecessary photoresist on the main portion, edge portion, and back portion of the substrate has been implemented.

  Japanese Patent Publication No. 4-49938 (Patent Document 1) relates to a thinner composition and discloses a method of removing a photoresist using propylene glycol methyl ether acetate. Further, JP-A-4-42523 (Patent Document 2) relates to a thinner composition, and discloses a method for removing an unnecessary resist using an alkylalkoxypropionate.

  As an organic solvent used in the thinner composition for removing the photoresist, although ethylene glycol monoethyl ether acetate has a high dissolution rate, it has high volatility and flammability, especially for reproductive toxicity such as leucopenia and fetal miscarriage. There's a problem. In addition, ethyl lactate has a high viscosity and a low dissolution rate, so that a sufficient cleaning effect cannot be obtained by itself, and organic solvents such as acetone and methyl ethyl ketone have a low flash point and work stability is significantly reduced. was there.

  Accordingly, there is a need for further research on a thinner composition that can efficiently remove unnecessary photoresist adhering to the edge and rear surface portion of a glass substrate used in a liquid crystal display device and a wafer used in semiconductor manufacturing in a short time. Is the actual situation.

Japanese Patent Publication No. 4-49938 JP-A-4-42523

The present invention solves the above-mentioned problems of the prior art, and removes unnecessary photoresist adhering to the edge and rear portion of a glass substrate used in a liquid crystal display device and a wafer used in semiconductor manufacturing in a short time. An object of the present invention is to provide a thinner composition for removing a photoresist, which can be efficiently removed by the above method.
Another object of the present invention is to remove photoresist that is highly stable to the human body, safer for workers and applicable to various processes, and can improve the production yield of liquid crystal display devices and semiconductor manufacturing processes. A thinner composition is provided.

In order to achieve the above object, the present invention provides: a) propylene glycol monoalkyl ether acetate,
There is provided a thinner composition for removing a photoresist comprising b) an alkyl ethanoate, and c) an alkyl lactate.
Preferably, the thinner composition comprises
a) 1-70 parts by mass of propylene glycol monoalkyl ether acetate,
b) 10-90 parts by weight of alkyl ethanoate, and c) 1-10 parts by weight of alkyl lactate.
The present invention further provides a) propylene glycol monoalkyl ether acetate,
b) alkyl ethanoates,
A thinner composition for removing a photoresist, comprising: c) an alkyl lactate; and d) a polyethylene oxide-based condensate.
Preferably, the thinner composition comprises
a) 1-70 parts by mass of propylene glycol monoalkyl ether acetate,
b) 10 to 90 parts by mass of an alkyl ethanoate,
c) Alkyl lactate 1 to 10 parts by mass, and d) Polyethylene oxide condensate 0.001 to 1 part by mass.
Furthermore, the present invention provides a thinner composition for removing a photoresist.
a) propylene glycol monoalkyl ether acetate,
b) alkyl ethanoates,
A photoresist removal thinner composition comprising c) an alkyl lactate, and e) a fluorinated acrylic copolymer.
Preferably, the thinner composition comprises
a) 1-70 parts by mass of propylene glycol monoalkyl ether acetate,
b) 10 to 90 parts by mass of an alkyl ethanoate,
c) 1 to 10 parts by weight of alkyl lactate, and e) 0.001 to 0.1 parts by weight of fluorinated acrylic copolymer.
Furthermore, the present invention provides a thinner composition for removing a photoresist.
a) propylene glycol monoalkyl ether acetate,
b) alkyl ethanoates,
c) alkyl lactate,
There is provided a thinner composition for removing a photoresist comprising d) a polyethylene oxide-based condensate, and e) a fluorinated acrylic copolymer.
Preferably, the thinner composition comprises
a) 1-70 parts by mass of propylene glycol monoalkyl ether acetate,
b) 10 to 90 parts by mass of an alkyl ethanoate,
c) Alkyl lactate 1-10 parts by weight,
d) 0.001 to 1 part by mass of a polyethylene oxide condensate, and e) 0.001 to 0.1 part by mass of a fluorinated acrylic copolymer.

  The thinner composition for removing a photoresist according to the present invention efficiently removes unnecessary photoresist adhering to a glass substrate used in a liquid crystal display device and an edge of a wafer used for manufacturing a semiconductor and a rear surface portion in a short time. Not only can be done at the same time, it is also highly stable to the human body, safer for workers and applicable to various processes, and can simplify the liquid crystal display device and semiconductor manufacturing process and improve the production yield economically There are advantages.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.
While the inventors have conducted research on a thinner composition that is harmless to the human body and can efficiently remove the photoresist in a short time, propylene glycol monoalkyl ether acetate, alkyl ethanoate, and alkyl lactate are used. The thinner composition produced in this way not only removes unnecessary photoresist adhering to the edge and rear surface of the glass substrate used in liquid crystal display devices and the wafer used in semiconductor manufacturing in a short time. The present invention has been completed by confirming that it has high stability to the human body and can be applied to various processes, can simplify the liquid crystal display device and the semiconductor manufacturing process, and can improve the production yield economically. It was.
The thinner composition for removing a photoresist of the present invention comprises a) propylene glycol monoalkyl ether acetate, b) alkyl ethanoate, and c) alkyl lactate.

  The propylene glycol monoalkyl ether acetate of a), the alkyl ethanolate of b), and the alkyl lactate of c) used in the present invention are used as solvents in thinner compositions, each of which is extremely pure of semiconductor grade. In the VLSI grade, those filtered to the 0.1 μm level are used.

  The propylene glycol monoalkyl ether acetate a) used in the present invention is preferably an alkyl group having 1 to 5 carbon atoms, specifically, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate. , Propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, and the like are more preferable, and it is particularly preferable to use propylene glycol monomethyl ether acetate having excellent solubility in a polymer.

The propylene glycol monomethyl ether acetate has high stability and safety to the human body when exposed to air, and is safe because it is rapidly decomposed into propylene glycol and alcohol in the human body in terms of substance metabolism. Furthermore, the toxicity test shows LD ₅₀ (mouse) = 8.5 g / kg, which indicates 50% lethal dose of mice by oral administration, and is rapidly degraded by hydrolysis. Its physical properties are a boiling point of 146 ° C., a flash point of 42 ° C. (measured by a closed cup method), a viscosity of 1.17 cps (25 ° C.), and a surface tension of 26 dyne / cm.

  The propylene glycol monoalkyl ether acetate of a) is preferably contained in an amount of 1 to 70 parts by mass with respect to 100 parts by mass of the thinner composition. In that case, it exhibits an appropriate volatility and dissolving power and is effective in removing the photoresist. Is.

The alkyl ethanoate of b) used in the present invention is preferably an alkyl group having 1 to 4 carbon atoms, and specific examples thereof include, for example, methyl ethanoate, ethyl ethanoate, isopropyl ethanoate, normal Examples thereof include propyl ethanoate or butyl ethanoate.
As the alkyl ethanoate of b), preferably, isopropyl ethanoate, normal propyl ethanoate or butyl ethanoate having a relatively low viscosity and suitable volatility is used. Most preferably, butyl ethanoate is used which has excellent solubility in various resins, in particular not only low surface tension, but also can exhibit excellent interface characteristics even when only a predetermined content is added to the thinner composition. Butylethanoate shows LD ₅₀ (mouse) = 7.0 g / kg which shows 50% lethal dose of mice by oral administration in toxicity experiment, physical properties are boiling point 126.1 ° C, flash point 23 ° C (measured by closed cup method) ), A viscosity of 0.74 cps (25 ° C.), and a surface tension of 25 dyne / cm.

The alkyl ethanoate of b) is preferably contained in an amount of 10 to 90 parts by mass with respect to 100 parts by mass of the thinner composition, and in this case, it exhibits an appropriate volatility and dissolving power and is effective in removing the photoresist. .
As the alkyl lactate of c) used in the present invention, methyl lactate, ethyl lactate, butyl lactate or the like is also used.

In particular, the ethyl lactate is highly stable to the human body at the US Food and Drug Administration (FDA), and is currently used as a food additive. Ethyl lactate shows LD ₅₀ (mouse) = 5.0 g / kg, which indicates 50% lethal dose of mice by oral administration in toxicity experiments, and is also safely decomposed into lactic acid and ethanol in the human body in terms of substance metabolism. is there. The physical properties are a boiling point of 156 ° C., a flash point of 52 ° C. (measured by a closed cup method), a viscosity of 2.38 cps (25 ° C.), a surface tension of 34 dyne / cm, and a solubility parameter = 10.

  The alkyl lactate of c) is superior in solubility in the photosensitive agent component of the photosensitive resin as compared with other different solvents, and is preferably contained in 1 to 10 parts by mass with respect to 100 parts by mass of the thinner composition. In that case, the viscosity can be lowered, and when used as a thinner, there is an effect that excellent characteristics can be exhibited.

Furthermore, the thinner composition for removing a photoresist of the present invention can contain d) a polyethylene oxide-based condensate.
The polyethylene oxide-based condensate acts as a nonionic surfactant in the thinner composition, exhibits excellent solubility in water and various solvents, and when the thinner comes into contact with the photoresist, the step is effective at the interface. It works to reduce it.

  The polyethylene oxide condensate of d) is a condensation product obtained by condensing a linear or branched alkylphenol having 6 to 12 carbon atoms with 5 to 25 mol of ethylene oxide per mol of the alkylphenol. Is preferably included. Specific examples of the alkyl-substituted product in the compound as described above include condensation of about 9.5 mol of ethylene oxide per mol of nonylphenol derived from polymerized propylene, di-isobutylene, octene, or nonene. Nonylphenol, dodecylphenol condensed with about 12 mol of ethylene oxide per mol of phenol, or di-isooctylphenol condensed with about 15 mol of ethylene oxide per mol of phenol.

  The polyethylene oxide-based condensate d) is preferably contained in an amount of 0.001 to 1 part by mass with respect to 100 parts by mass of the thinner composition. In this case, the effects of thinner volatility and detergency at the edge of the substrate are maintained. Therefore, it is easy to use without the generation of bubbles.

Further, the thinner composition for removing a photoresist of the present invention may include e) a fluorinated acrylic copolymer.
The fluorinated acrylic copolymer of e) has excellent solubility in water and various solvents.

  The fluorinated acrylic copolymer of e) preferably has a mass average molecular weight of 3,000 to 10,000, a flash point of 200 ° C. (measured by an open cup method), a specific gravity of 1.10 g / mL (25 ° C.), and a viscosity of 2100 cst ( 20 ° C.) and surface tension (in the form of ethyl lactate) of 24.0 mN / m (Wilhermy method) are preferred. Further, the fluorinated acrylic copolymer of e) is preferably used by diluting and mixing with ethyl lactate.

  The fluorinated acrylic polymer of e) is preferably contained in an amount of 0.001 to 0.1 parts by mass with respect to the thinner composition. In that case, the dynamic surface tension can be lowered at the interface with the photoresist to perform excellent removal.

  The thinner composition for removing a photoresist of the present invention composed of the components as described above removes unnecessary photoresist generated on the edge and rear surface portions of the substrate by spraying by a dropping or spraying method through a nozzle.

  Further, the dropping or spraying amount of the thinner composition for removing the photoresist can be adjusted according to the type of photosensitive resin used and the thickness of the film, and is preferably in the range of 5 to 100 cc / min. It is preferable to select and use the flow rate within the range. In the present invention, after spraying the thinner composition as described above, a fine circuit pattern can be formed through a subsequent photolithography process.

  The thinner composition for removing a photoresist of the present invention as described above efficiently removes unnecessary photoresist attached to the edge and the rear surface of a glass substrate used in a liquid crystal display device and a wafer used in semiconductor manufacturing in a short time. In addition to being able to be removed at the same time, it is highly stable to the human body at the same time, making it safer and applicable to various processes for workers, simplifying the liquid crystal display device and semiconductor manufacturing process, and improving the production yield economically There are advantages that can be made.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited by these Examples.

[Example]
Example 1
A thinner composition is prepared by uniformly mixing 10 parts by mass of propylene glycol monoethylether acetate (PGMEA), 80 parts by mass of butyl acetate (NBA) and 10 parts by mass of ethyl lactate (EL). Manufactured.

Examples 2 to 5 and Comparative Examples 1 to 4
A thinner composition was produced in the same manner as in Example 1 except that the composition ratio was the same as the components shown in Table 1 below. The units in Table 1 are parts by mass.

In order to measure the degree of unnecessary photoresist removal by the thinner compositions prepared in Examples 1 to 5 and Comparative Examples 1 to 4, an EBR experiment was performed as shown below, and the results are shown in Table 4.
First, an 8-inch diameter silicon oxide substrate was washed with two baths each containing a hydrogen peroxide / sulfuric acid mixture (submerged in each bath for 5 minutes) and then rinsed with ultrapure water. This process was performed with custom-made cleaning equipment. Thereafter, these substrates were spin-dried with a spin dryer (VERTEQ product, model SRD 1800-6). Thereafter, each photoresist shown in Table 2 was coated on the upper surface of the substrate to a certain thickness using a rotary coating machine (EBR TRACK, Koryo Semiconductor Co., Ltd.). In the coating operation, 10 cc of photoresist was dropped on the center of the stopped substrate. Thereafter, the photoresist was distributed at 500 rpm for 3 seconds using a rotary coater, and then the substrate was accelerated at a rotational speed of about 2,000 to 4,000 rpm to adjust each photoresist to a predetermined thickness. The rotation time at this time is about 20 to 30 seconds.

  Each of the thinner compositions prepared in Examples 1 to 5 and Comparative Examples 1 to 4 was sprayed onto the substrate coated with the photoresist prepared as described above, and the photoresist was removed under the conditions shown in Table 3. . At this time, each thinner composition is supplied by a pressure cylinder equipped with a pressure gauge, the pressurized pressure at this time is 1.0 kgf, and the flow rate of the thinner composition from the EBR nozzle is 10 to 20 cc / min. did.

From Table 4 above, the thinner compositions of Examples 1 to 5 show excellent EBR performance (EBR line uniformity) for all photoresists, particularly polyethylene oxide condensates, fluorinated acrylic copolymers, or these. In the case of Examples 3 to 5 in which the mixture was used, the EBR performance was further improved, and it was found that the thinner composition of the present invention was excellent in the photoresist removal performance.
On the other hand, in the case of Comparative Examples 1 to 4 that do not contain propylene glycol monoalkyl ether acetate, alkyl ethanolate, and alkyl lactate as in the present invention, the penetration to the photoresist is suppressed, and the performance is remarkably higher than that of Examples and the like. We were able to confirm that it decreased.

Claims (13)

a) propylene glycol monoalkyl ether acetate,
A thinner composition for removing a photoresist comprising b) an alkyl ethanoate, and c) an alkyl lactate. a) 1-70 parts by mass of propylene glycol monoalkyl ether acetate,
The thinner composition for removing a photoresist according to claim 1, comprising: b) 10 to 90 parts by mass of an alkyl ethanoate; and c) 1 to 10 parts by mass of an alkyl lactate.   The propylene glycol monoalkyl ether acetate is selected from the group consisting of propylene glycol monomethyl ether acetate having 1 to 5 carbon atoms in the alkyl group, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, and propylene glycol monobutyl ether acetate. The thinner composition for removing a photoresist according to claim 1, wherein the composition is one or more selected from the above.   The alkyl ethanoate is one or more selected from the group consisting of methyl ethanoate, ethyl ethanoate, isopropyl ethanoate, normal propyl ethanoate, and butyl ethanoate having an alkyl group having 1 to 4 carbon atoms. Item 4. A thinner composition for removing a photoresist according to Item 1.   The thinner composition for removing a photoresist according to claim 1, wherein the alkyl lactate is at least one selected from the group consisting of methyl lactate, ethyl lactate, and butyl lactate. a) propylene glycol monoalkyl ether acetate,
b) alkyl ethanoates,
A thinner composition for removing a photoresist, comprising: c) an alkyl lactate; and d) a polyethylene oxide-based condensate. a) 1-70 parts by mass of propylene glycol monoalkyl ether acetate,
b) 10 to 90 parts by mass of an alkyl ethanoate,
The thinner composition for removing a photoresist according to claim 6, comprising: c) 1 to 10 parts by mass of an alkyl lactate, and d) 0.001 to 1 part by mass of a polyethylene oxide-based condensate.   The polyethylene oxide-based condensate is a condensation product obtained by condensing a linear or branched alkylphenol having an alkyl group having 6 to 12 carbon atoms and 5 to 25 mol of ethylene oxide per mol of the alkylphenol. A thinner composition for removing a photoresist as described in 1. a) propylene glycol monoalkyl ether acetate,
b) alkyl ethanoates,
A thinner composition for removing a photoresist, comprising: c) an alkyl lactate; and e) a fluorinated acrylic copolymer. a) 1-70 parts by mass of propylene glycol monoalkyl ether acetate,
b) 10 to 90 parts by mass of an alkyl ethanoate,
The thinner composition for removing a photoresist according to claim 9, comprising: c) 1 to 10 parts by mass of an alkyl lactate, and e) 0.001 to 1 part by mass of a fluorinated acrylic copolymer.   The thinner composition for removing a photoresist according to claim 9, wherein the fluorinated acrylic copolymer has a mass average molecular weight of 3,000 to 10,000. a) propylene glycol monoalkyl ether acetate,
b) alkyl ethanoates,
c) alkyl lactate,
A thinner composition for removing a photoresist, comprising: d) a polyethylene oxide-based condensate; and e) a fluorinated acrylic copolymer. a) 1-70 parts by mass of propylene glycol monoalkyl ether acetate,
b) 10 to 90 parts by mass of an alkyl ethanoate,
c) Alkyl lactate 1-10 parts by weight,
The thinner composition for removing a photoresist according to claim 12, comprising: d) 0.001 to 1 part by mass of a polyethylene oxide-based condensate; and e) 0.001 to 0.1 part by mass of a fluorinated acrylic copolymer.