KR101370704B1 - thinner composition for removing photosensitive resin and anti-reflective coating - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thinner composition for removing a photosensitive resin and an antireflective film used in a semiconductor device and a thin film transistor liquid crystal display device manufacturing process, and more particularly, ethyl-3-ethoxy propionate (EEP), methyl-3- 30 to 90 weight percent of one selected from the group consisting of methoxy propionate (MMP) and mixtures thereof; Ethyl lactate (EL) 1-20 wt%; The present invention relates to a thinner composition for removing a photosensitive resin and an anti-reflection film, comprising 5 to 50 wt% of cyclohexanone (CHN).

Photosensitive resin, thinner, anti-reflection film, photolithography, semiconductor device

Description

Thinner composition for removing photosensitive resin and anti-reflective coating

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thinner composition for removing a photosensitive resin and an anti-reflection film used in a semiconductor device and a thin film transistor liquid crystal display device manufacturing process. The present invention relates to a thinner composition having excellent solubility and EBR properties with respect to an antireflection film (BARC), and having excellent properties even in a process of pretreating the wafer surface in order to improve coating performance of photoresist.

Photolithography process in the manufacturing process of the semiconductor device is to apply the photosensitive resin composition on the wafer, transfer the pre-designed pattern and then form the electronic circuit through the etching process appropriately according to the transferred pattern This is one of the most important tasks. The photolithography process includes (1) a coating step of uniformly applying the photosensitive resin composition to the surface of the wafer, and (2) a soft baking step of evaporating the solvent from the coated photosensitive film so that the photosensitive film adheres to the surface of the wafer. (3) an exposure process of transferring a mask pattern onto the photoresist by exposing the photoresist while repeatedly reducing the circuit pattern on the mask repeatedly and sequentially using a light source such as ultraviolet ray, and (4) exposure to a light source. Development process that selectively removes parts with different physical properties such as difference in solubility according to photosensitivity by using photodevelopment solution, and (5) to more closely adhere the photoresist film remaining on the wafer to the wafer after development. A hard baking process, (6) an etching process of etching certain portions according to the developed photoresist pattern, and (7) a fire after the process. It advances to the peeling process etc. which remove the photosensitive film which became necessary.

In the photolithography process, the photocoating film is supplied onto the wafer and the substrate is rotated to spread the surface evenly by centrifugal force, so that the photoresist film is gathered at the edge portion and the rear surface of the substrate due to the centrifugal force to form a small spherical material. The spherical material may be peeled off during transfer of the substrate after the baking process to cause particles in the apparatus, or may cause defocus during exposure. This unnecessary photosensitive material causes equipment contamination and lowers the yield in the manufacturing process of the semiconductor device. To remove this, spray nozzles are installed above and below the edge portion and the rear portion of the substrate, and the edge portion and the rear portion are disposed through the nozzle. The thinner composition composed of the organic solvent component is sprayed on and removed.

Factors that determine the performance of the thinner composition include dissolution rate and volatility. The dissolution rate of the thinner composition is very important because of its ability to dissolve and remove the photosensitive resin quickly and effectively. Specifically, in the rinse of the edge portion, it may have a smooth processing cross section only if it has an appropriate dissolution rate. If the dissolution rate is too high, a photoresist attack may appear in the rinse of the photoresist applied to the substrate. On the contrary, when the dissolution rate is too low, a partially dissolved photosensitive film tail flow phenomenon called tailing may appear in the rinse of the photosensitive film applied to the substrate. In particular, in the case of the rinsing process using a rotary spreader due to the high integration of semiconductor integrated circuits and the large diameter of the substrate due to the high density, the low rotation speed (rpm) of the rotation speed is inevitable. In this rinse process, when the substrate does not have a proper dissolution rate at the contact speed of the thinner composition and the fluctuation of the substrate due to the low rotational speed, bounding occurs and the use of the unnecessary thinner composition increases. In the low rotation rinse process due to the large diameter of such a substrate, a stronger dissolution rate of the thinner is required than the conventional high rotation rinse process.

In addition, volatility is required to not volatilize easily and remain on the surface of the substrate after removing the photosensitive resin. If the volatility is too low to remain volatilized in the thinner composition, the remaining thinner itself may act as a contaminant in various processes, in particular, subsequent etching, and thus may act as a problem of lowering the yield of the semiconductor device. If the volatility is too high, the substrate may be rapidly cooled and the thickness variation of the applied photoresist film may increase, and the volatilization may easily be volatilized to the air during use to contaminate the cleanliness itself. As a result, all kinds of defects such as tailing and photoresist attack are a direct cause of lowering the yield of semiconductor devices.

Meanwhile, the conventional thinner compositions are as follows.

Japanese Patent Application Laid-Open No. 63-69563 proposes a method of removing a thinner composition by contacting an unnecessary photoresist film of an edge upside part, an edge side part, and an edge back side part of a substrate. have. Examples of the solvent for removing the photoresist film include ethers and ether acetates such as cellosolve acetate, propylene glycol ether, and propylene glycol ether, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, and methyl. Ester, such as lactate, ethyl lactate, methyl acetate, ethyl acetate, and butyl acetate, is used. The solvent is used as a thinner composition, and a method of removing the thinner composition by contacting the photosensitive film of the substrate, the flue part, and the back part of the substrate is unnecessary. A method of using alkoxy propionate is disclosed.

However, i-line photoresist, KrF photoresist, ArF photoresist, KrF photoresist antireflection film, ArF photoresist antireflection film, etc., which are currently used as photoresist in semiconductor lithography process, all have different main components. There is a problem that a sufficient cleaning effect cannot be obtained by itself.

In order to solve this problem, a method of using a mixture of conventional single solvents has been researched and developed.

Japanese Patent Application Laid-Open No. Hei 4-130715 uses a thinner composition composed of a mixed solvent consisting of an alkyl pyrupinic acid solvent and methyl ethyl ketone. Japanese Laid-Open Patent Publication No. 7-146562 uses a thinner composition composed of a mixture of propylene glycol alkyl ether and alkyl 3-alkoxy propionate. Japanese Laid-Open Patent Publication No. 7-128867 uses a thinner composition composed of a mixture of propylene glycol alkyl ether and butyl acetate and ethyl lactate or a mixture of butyl acetate and ethyl lactate and propylene glycol alkyl ether acetate. Japanese Patent Application Laid-Open No. 7-160008 uses a thinner composition composed of a mixture of propylene glycol alkyl ether propionate and methyl ethyl ketone, or a mixture of propylene glycol alkyl ether propionate and butyl acetate. US Patent No. 4,983,490 uses a mixed solvent of propylene glycol alkyl ether acetate and propylene glycol alkyl ether as a thinner composition, and US Patent No. 4,886,728 uses a mixture consisting of ethyl lactate and methyl ethyl ketone as a thinner composition. .

However, even with the above-described mixed solvents, there are many difficulties in the application of semiconductor devices and thin film transistor liquid crystal display devices, which are becoming increasingly integrated and large in diameter.

In the process of uniformly applying the photosensitive resin composition to the wafer surface, as in the Republic of Korea Patent Publication No. 2003-0095033, the thinner is first applied before the photoresist is applied to the wafer surface to lower the surface tension of the wafer. The process of apply | coating a photoresist and apply | coating uniformly, overcoming the step | step difference of a pattern by the quantity of a small amount of photoresist is performed.

However, even in this case, when the volatility of the thinner is high, the photoresist does not spread evenly, and the phenomenon of cracking at the edge of the wafer may occur because the step of the fine pattern cannot be overcome on the wafer. If the volatility is too low, a problem arises in which the photoresist is attacked by the remaining thinner during photoresist application. As well as volatilization, the shape to be applied is due to the surface tension of the organic solvent, the organic solvent contained in the photoresist, and the structure of the photosensitive resin which is the main component of the photoresist, and thus requires a thinner composition that satisfies all of them.

The present invention compensates for the shortcomings of the conventional thinner composition, and the uniform removal performance of the unnecessary photoresist film generated at the edge portion or the rear portion of the substrate due to the large diameter of the substrate used in the manufacture of the semiconductor device and the thin film transistor liquid crystal display device. It is an object to provide a thinner composition having a. In addition, it has excellent solubility and EBR characteristics for various photoresist and anti-reflective coating (BARC) including i-line, KrF, ArF photoresist, and improves the coating performance of photoresist before applying photoresist. It is an object of the present invention to provide a thinner composition having excellent properties even in the process of pre-treating the wafer surface by first applying the thinner composition. In addition, the object of the present invention is to provide a thinner composition for removing photosensitive resin having high work stability and low corrosion because there is no toxicity to the human body and there is no discomfort due to smell.

Another object of the present invention is to provide a method for manufacturing a semiconductor device and a thin film transistor liquid crystal display device using the thinner composition for removing the photosensitive resin.

In order to achieve the above object, the present invention is selected from the group consisting of ethyl-3-ethoxy propionate (EEP), methyl-3-methoxy propionate (MMP) and mixtures thereof from 30 to 30 90 wt%; Ethyl lactate (EL) 1-20 wt%; It provides a thinner composition comprising 5 to 50% by weight of cyclohexanone (CHN).

In addition, the present invention provides a method of manufacturing a semiconductor device or a thin film transistor liquid crystal display device by spraying the thinner composition on the edge portion and the rear portion of the substrate to which the photosensitive resin composition is applied to remove unnecessary photoresist.

The thinner composition for removing a photosensitive resin according to the present invention is used on the edge portion and the rear portion of the substrate used in the semiconductor device and the thin film transistor liquid crystal display device manufacturing method can efficiently remove the unnecessary photosensitive film in a short time. In particular, it has excellent solubility and EBR characteristics for various photoresists and lower antireflection films (BARC), including photoresists for i-line, KrF, ArF. It also has excellent performance in the process of first applying the thinner composition to improve the coating performance of the photoresist before applying the photoresist. In addition, the thinner composition for removing the photosensitive resin of the present invention has no toxicity to humans, no discomfort due to odor, and thus has high work stability and low corrosiveness.

Hereinafter, the present invention will be described in detail.

The thinner composition of the present invention is one selected from the group consisting of ethyl-3-ethoxy propionate (EEP), methyl-3-methoxy propionate (MMP) and mixtures thereof, ethyl lactate (EL) And cyclohexanone (CHN).

One selected from ethyl-3-ethoxy propionate (EEP), methyl-3-methoxy propionate (MMP), and mixtures thereof, included in the thinner composition of the present invention is 30 based on the total weight of the composition. To 90% by weight, preferably 40 to 80% by weight. When included in the above-described range, the coating property with the substrate is excellent in the pretreatment step of the wafer surface, and the solubility in a specific film such as a photoresist for ArF or an antireflection film is excellent.

The ethyl-3-ethoxy propionate and methyl-3-methoxy propionate are nonacetic acid ester compounds, and novolak resins, which are main components constituting i-line photoresist, KrF photoresist, and ArF photoresist, It has a suitable dissolution rate with respect to the polyhydroxy styrene and the acrylic copolymer partially substituted with a photosensitive agent, a protecting group. In particular, the ethyl-3-ethoxy propionate has a viscosity of about 1.2 cP at room temperature even though the volatilization temperature is 168 ° C., thereby providing excellent coating property on the wafer surface.

Ethyl lactate included in the thinner composition of the present invention is a nonacetic acid ester compound, which is included in an amount of 1 to 20% by weight based on the total weight of the composition. When included in the above-described range, the coating property with the substrate is excellent, and the EBR characteristic for the specific photoresist is excellent.

Cyclohexanone contained in the thinner composition of the present invention is included in 5 to 50% by weight, preferably 10 to 40% by weight based on the total weight of the composition. When the above-mentioned range is satisfied, the solubility of a specific resist becomes excellent, the rise of surface tension is suppressed, and the EBR characteristic becomes excellent.

The thinner composition of the present invention may further comprise a surfactant. As the surfactant, it is preferable to use a fluorine series, nonionic series or ionic series surfactant. The surfactant is preferably included in 10 to 500 ppm by weight. When included in the above-mentioned range, the EBR characteristic is further improved.

In addition, the thinner composition of the present invention may be used in a method of manufacturing a semiconductor device or a thin film transistor liquid crystal display device by spraying on the edge portion and the rear portion of the substrate to which the photosensitive resin composition is applied to remove unnecessary photoresist. At this time, the injection amount of the thinner composition is preferably 5 to 50 cc / min.

After the process, the manufacturing of the semiconductor device and the thin film transistor liquid crystal display device may be manufactured by a general technique known in the art.

The thinner composition of the present invention has excellent solubility in various photoresist films and bottom antireflection films (BARC). EBR characteristics and photoresist coating performance can be improved. In particular, since the basic structure of the photosensitive resin constituting the i-line, KrF, ArF photoresist is different, it is necessary to control the composition content of the organic solvent to improve the solubility and coating properties of all of them, The thinner composition satisfies this.

In addition, since the components of the thinner composition are environmentally friendly, it is possible to actively cope with recent environmental issues. As a result, it is possible to economically produce highly reliable semiconductor devices, thereby reducing the time and cost required for the overall semiconductor manufacturing process and reducing costs for preventing environmental pollution. After all, this is a competitive technology that can be applied to the manufacturing process of the next-generation devices having a fine line width.

The present invention will be described in more detail with reference to the following examples and comparative examples. However, the following examples are for illustrating the present invention and the present invention is not limited by the following examples.

Example 1  To 5 and Comparative Example 1  To 7: photosensitive resin and Antireflection film  For removal Thinner  Preparation of the composition

Each component was added to the mixing tank equipped with a stirrer at the composition ratio shown in Table 1, and then stirred at a speed of 500 rpm for 1 hour at room temperature to prepare a thinner composition for removing the photosensitive resin and the antireflective film.

EEP
(weight%) MMP
(weight%) EL
(weight%) CHN
(weight%) Example 1 30 30 10 30 Example 2 60 - 10 30 Example 3 - 60 10 30 Example 4 75 - 10 15 Example 5 - 75 10 15 Comparative Example 1 70 - - 30 Comparative Example 2 90 - 10 - Comparative Example 3 30 - 30 40 Comparative Example 4 - 65 30 5 Comparative Example 5 - 55 40 5 Comparative Example 6 30 - 70 - Comparative Example 7 - 30 70 -

EEP: Ethyl-3-ethoxy propionate

MMP: methyl-3-methoxy propionate

EL: ethyl lactate

CHN: cyclohexanone

Test Example 1 : For photosensitive resin composition Thinner  Unnecessary photoresist removal experiment of composition

After applying the photosensitive resin composition shown in Table 2 to a 4 inch silicon oxide substrate, the thinner compositions of Examples 1 to 5 and Comparative Examples 1 to 7 were edged under the conditions described in Table 3. The experiment to remove the unnecessary photoresist of (Edge Bead Removing experiment: hereinafter referred to as EBR experiment) was carried out. The thinner compositions of each of Examples 1 to 5 and Comparative Examples 1 to 7 were fed from a pressure vessel equipped with a pressure gauge, the pressure being 1 kgf, and the flow rate of the thinner composition coming out of the EBR nozzle was 10 to 30 cc / min was set. In addition, the removal performance of the unnecessary photosensitive film was evaluated using an optical microscope and a scanning electron microscope, and the results are shown in Table 4 below.

division Composition type Resin series Film thickness (占 퐉) PR 1 PR for i-line Novolac 1.10 PR 2 PR for KrF Acetal (PHS) 1.30 PR 3 PR for KrF tBoc (PHS) 0.89 PR 4 PR for ArF Acrylate 0.25 BARC-1 BARC for KrF - 0.06 BARC-2 BARC for ArF - 0.04

division Rotational speed (rpm) Time (sec) Dispense condition 300 ~ 2000 7 Spin coating Adjustable according to the photoresist thickness 15 EBR Condition 1 2000 20 EBR Condition 2 2000 25 Drying conditions 1300 6

PR 1 PR 2 PR 3 PR 4 BARC-1 BARC-2 Example 1 ◎ ◎ ◎ ◎ ◎ ◎ Example 2 ◎ ◎ ◎ ◎ ◎ ◎ Example 3 ◎ ◎ ◎ ◎ ◎ ◎ Example 4 ◎ ◎ ◎ ○ ○ ○ Example 5 ◎ ◎ ◎ ○ ○ ○ Comparative Example 1 △ ○ ○ △ ○ ○ Comparative Example 2 ○ ○ △ X △ X Comparative Example 3 X ○ △ △ △ △ Comparative Example 4 ○ △ △ X △ X Comparative Example 5 △ ○ ○ ○ △ ○ Comparative Example 6 X △ △ ○ △ △ Comparative Example 7 X △ △ ○ △ △

Note: EBR line uniformity is constant for the photoresist film after EBR.

○: Good linear state with EBR line uniformity of 75% or more on the photoresist film after EBR

(Triangle | delta): The shape of the edge part after EBR was distorted by the thinner melt action.

X: Tailing phenomenon occurs at the edge film after EBR

Referring to Table 4, the thinner compositions of Examples 1 to 5 according to the present invention show excellent EBR performance for all photoresist films. On the other hand, Comparative Examples 1 to 7 was found to significantly reduce the removeability compared to the thinner composition of the present invention according to Examples 1 to 5 in suppressing the penetration into the photosensitive film. As a result, it can be seen that it satisfies the EBR performance of many kinds of photoresist and BAR.

In addition, even when changing the rotational speed (rpm) conditions of the EBR was maintained equally good form. This means that the thinner composition according to the present invention is not only effective under specific conditions, but also exhibits the same performance under various conditions, and is more stable than conventional thinner compositions against changes in process conditions.

Test Example 2 : Photoresist  Dissolution Rate Experiment by Type

Dissolution rates for the six photoresists of Table 2 were tested using the thinner compositions of Examples 1-5 and Comparative Examples 1-7. After six photoresists were applied to a 6-inch silicon oxide substrate using a DRM device, the dissolution rate was measured while developing the entire surface in each thinner composition without exposing the wafer after the soft baking process. In the case of BARC-1 and BARC-2, the dissolution rate was measured while the entire surface was developed in each thinner composition without heat treatment after application.

PR 1 PR 2 PR 3 PR 4 BARC-1 BARC-2 Example 1 ◎ ◎ ◎ ◎ ◎ ◎ Example 2 ◎ ◎ ◎ ◎ ◎ ◎ Example 3 ◎ ◎ ◎ ◎ ◎ ◎ Example 4 ◎ ◎ ◎ ○ ○ ○ Example 5 ◎ ◎ ◎ ○ ○ ○ Comparative Example 1 ○ ○ ◎ ◎ ○ ◎ Comparative Example 2 ◎ ◎ ◎ ○ ○ △ Comparative Example 3 △ ○ ○ ◎ ○ ◎ Comparative Example 4 ◎ ◎ ◎ ○ ○ △ Comparative Example 5 ○ ◎ ○ ○ ○ △ Comparative Example 6 △ ◎ ○ ○ ○ △ Comparative Example 7 △ ◎ ○ ○ ○ △

NOTE: When the dissolution rate is 700 nm / sec or more.

(Circle): When melt rate is less than 700 nm / sec from 400 nm / sec or more.

(Triangle | delta): When melt rate is less than 400 nm / sec in 100 nm / sec or more.

X: dissolution rate is 100 nm / sec or less

city Example 3 : Photoresist  Evaluation of Coating Uniformity by Type

Coating uniformity for the six photoresists of Table 2 was tested using the thinner compositions of Examples 1-5 and Comparative Examples 1-7. After the photoresist was applied on the 6-inch silicon oxide substrate according to the recipe as shown in Table 6, a total of 8 spots and 9 spots in total were X-shaped at the center of the wafer and the center of the wafer. Measurement) to confirm that the photoresist was uniformly applied.

Step Time (sec) Speed (rpm) The accelerator (rpm / sec) Dispensing (cc) One 5 0 10,000 2.0 (thinner) 2 5 700 10,000 0 3 3 2,500 10,000 0 4 20 2,500 10,000 0.30 (PR) 5 5 700 10,000 0 6 5 0 10,000 0

PR 1 PR 2 PR 3 PR 4 BARC-1 BARC-2 Example 1 ◎ ◎ ◎ ◎ ◎ ○ Example 2 ◎ ◎ ◎ ◎ ◎ ○ Example 3 ◎ ◎ ◎ ◎ ◎ ◎ Example 4 ◎ ◎ ◎ ◎ ◎ ◎ Example 5 ◎ ◎ ◎ ◎ ◎ ◎ Comparative Example 1 ○ ◎ ◎ ◎ ○ ○ Comparative Example 2 ◎ ◎ ◎ ◎ ◎ ○ Comparative Example 3 ○ ◎ ◎ ○ ○ ○ Comparative Example 4 ○ ◎ ◎ ◎ ○ ○ Comparative Example 5 ○ ◎ ◎ ○ ○ ○ Comparative Example 6 ○ ◎ ◎ ○ ○ ○ Comparative Example 7 ○ ○ ○ ○ ○ ○

Note: When the standard deviation of the coating film thickness is 1% or less

○: when the standard deviation of the coating film thickness is 2% or less

(Triangle | delta): When the standard deviation of coating film thickness is 3% or less

X: Standard deviation of the coating film thickness is more than 3%

1 is a view showing a coating uniformity evaluation point according to the type of photoresist applied on the wafer.

Claims (7)

30 to 90 weight percent of one selected from the group consisting of ethyl-3-ethoxy propionate (EEP), methyl-3-methoxy propionate (MMP), and mixtures thereof; Ethyl lactate (EL) 1-20 wt%; Thinner composition for removing a photosensitive resin and an anti-reflection film comprising 5 to 50% by weight of cyclohexanone (CHN). The method according to claim 1, A thinner composition, further comprising a surfactant in the thinner composition. The method of claim 2, Thinner composition, characterized in that the surfactant is a fluorine-based, nonionic, or ionic surfactant. The method according to claim 1, The photosensitive resin is a thinner composition, characterized in that the photoresist for i-line, KrF, ArF. The method according to claim 1, The thinner composition is a thinner composition, characterized in that used in the process of pre-treating the wafer surface before applying the photoresist in the EBR process and the photoresist coating process. A method of manufacturing a semiconductor device or a thin film transistor liquid crystal display device, wherein the thinner composition according to claim 1 is sprayed on edges and rear portions of the substrate to which the photosensitive resin composition is applied to remove unnecessary photoresist films. The method of claim 6, The injection amount of the thinner composition is a method of manufacturing a semiconductor device or a thin film transistor liquid crystal display device is 5 to 50cc / min.

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