KR20040033526A - Thinner composition and method for stripping a photoresist using the same - Google Patents

Abstract

PURPOSE: A thinner composition and a stripping method of photoresist using the same are provided to be capable of obtaining excellent stripping characteristics and reducing the cost of thinner composition. CONSTITUTION: A thinner composition for stripping photoresist is mainly made of propylene glocol monomethyl ether acetate, ethyl 3-ethoxy propionate, and gamma-butyrolactone. Preferably, the contents of the propylene glocol monomethyl ether acetate, the ethyl 3-ethoxy propionate, and the gamma-butyrolactone are 50-80 weight%, 10-45 weight%, and 1-12 weight%, respectively. Preferably, the contents are 53-75 weight%, 12-30 weight%, and 2-10 weight%, respectively. Preferably, the thinner composition further contains surfactant.

Description

Thinner composition and method for stripping a photoresist using the same}

The present invention relates to a novel thinner composition and a method of stripping a photoresist using the same. More particularly, the present invention relates to novel thinner compositions that can be manufactured at low cost and to methods of stripping photoresist applied onto a substrate using the thinner compositions.

In order to manufacture a fine circuit, impurities must be precisely controlled and injected into a small area of a silicon substrate, and these areas are interconnected to form a device and a VLSI circuit. A pattern defining these areas is formed by a photolithography process. . That is, by applying a photoresist polymer film on the wafer substrate, it is selectively exposed by irradiating ultraviolet rays, electron beams or X-rays, and then developed. The remaining photoresist protects the applied substrate, and the portion where the photoresist is removed is used as a pattern to perform various additional or extractive processes on the substrate surface.

When performing the photolithography, defects in the application of the photoresist often occur. If such a defect occurs, the substrate on which the photoresist is applied is stripped to remove the photoresist, and the substrate is reused. This process is referred to as a wafer rework process (hereinafter referred to as 'REWORK').

In addition, when forming the photoresist layer, the photoresist is applied onto the substrate while mainly rotating the substrate. Then, the photoresist is also applied to the substrate edge and the back side. However, the photoresist applied to the substrate edge and the back surface may cause particles or the like in a subsequent process such as an etching or ion implantation process or cause pattern defects. Therefore, a process of stripping and removing the photoresist applied to the edge and the back surface of the substrate using the thinner composition (hereinafter referred to as an 'EBR process') is performed.

The photoresist used in the prior art is too slow or incompletely dissolved so that residual contaminants of the photoresist component on the substrate after stripping have not been removed in a subsequent process. In such a case, the yield of the apparatus is lowered, which adversely affects reliability.

On the other hand, as the degree of integration of semiconductor devices increases, photoresist compositions used in I-line and G-line have been developed, and these photoresist compositions have novolac resin as a main component. In addition, amplified photoresists that respond to excimer laser wavelengths or far ultraviolet rays have also been used. Therefore, there is a need for a stripping thinner composition of photoresist that exhibits excellent solubility in common with these various photoresists.

Recently presented thinner compositions are disclosed, for example, in US Pat. No. 5,866,305 (issued to Chon et al.) And in Korean patent 10-0265766.

U.S. Patent No. 5,866,305 discloses a thinner composition consisting of ethyl lactate and ethyl-3-ethoxy propionate, or ethyl lactate and ethyl-3-ethoxy propionate. Thinner compositions are disclosed that consist of nate and gamma-butyro lactone. Although the thinner composition disclosed in the above-mentioned US Patent No. 5,866,305 is currently used a lot, it is expensive because ethyl-3-ethoxy propionate is a main component. In addition, the thinner composition disclosed in the above-mentioned US Patent No. 5,866,305 has a disadvantage in that the dissolving ability in stripping of a specific photoresist, for example, amplified photoresist, is poor. Korean Patent No. 10-265766 discloses a thinner composition consisting of ethyl-3-ethoxy propionate, ethyl lactate and gamma-butyrolactone. The composition disclosed in Korean Patent No. 10-265766 is also very expensive since ethyl-3-ethoxy propionate is a main component.

In addition, Korean Patent Application Publication No. 2001-36461, filed Oct. 8, 1999 (Application No. 1999-43486) and published on May 7, 2001, by Applicant (assignee), includes acetone, gamma-butiro, A stripping composition based on lactones and ester compounds is disclosed. However, acetone, which is the main component of the thinner, has a strong penetration property, so that the edge profile of the photoresist is poor, especially in the EBR process. This is especially true for certain photoresists such as DUV photoresists. In addition, acetone has a very high volatilization degree, and thus generates residues, for example, when the EBR process is performed using a thinner made of NBA + GBL + acetone.

The thinner compositions may be commonly used for stripping of photoresist for reuse (REWORK process) and stripping of photoresist applied to substrate edge and backside (EBR process), but thinners having the same effect on both processes are needed. It is necessary to do

The thinner compositions also have the disadvantage of being expensive on the ingredients. This acts as a fatal defect in the manufacture of recent semiconductor devices requiring cost reduction.

Therefore, in recent years, there is a need for developing low-cost thinner compositions that do not interfere with stripping properties. The present inventors have developed and applied a new thinner composition (Korean Patent Application No. 2001-79490), and its domestic priority claim application (Korean Patent Application No. 2002-13631) is ongoing at the Korean Patent Office.

The inventors of the present invention further invented a novel thinner composition having a particularly preferred composition and a method of stripping a photoresist using the same.

Accordingly, it is a first object of the present invention to provide a novel thinner composition of low cost which has excellent stripping characteristics common to the REWORK process and the EBR process for most photoresists currently in use.

It is a second object of the present invention to provide a method for stripping a photoresist using the thinner composition.

1 is a process diagram illustrating a method for stripping photoresist applied to a substrate edge and a back surface area using a thinner composition according to an embodiment of the present invention.

2 is a flowchart illustrating a method for stripping a photoresist applied to the entire surface of a substrate using a thinner composition according to an embodiment of the present invention.

The present invention provides a thinner for photoresist strip thinner and strip method using the same, which is common to various photoresist and EBR / REWORK processes while increasing the content of low-cost PGMEA and reducing the content of relatively expensive EEP and GBL. It is about.

In order to achieve the first object of the present invention described above, the present invention provides a thinner composition for a photoresist strip, characterized in that consisting of propylene glycol monomethyl ether acetate, ethyl 3-ethoxy propionate and gamma-butyrolactone to provide.

The first object of the present invention described above may also be achieved in thinner compositions for photoresist strips consisting of propylene glycol monomethyl ether acetate, ethyl 3-ethoxy propionate and propylene glycol monomethyl ether.

In order to achieve the above-mentioned second object of the present invention, the present invention provides a thinner composition or propylene glycol mono for photoresist strip consisting of propylene glycol monomethyl ether acetate, ethyl 3-ethoxy propionate and gamma-butyrolactone. Preparing a photoresist strip thinner composition consisting of methyl ether acetate, ethyl 3-ethoxy propionate and propylene glycol monomethyl ether, contacting the thinner composition to the edge and / or back side of the substrate to which the photoresist is applied Stripping the photoresist and drying the thinner composition in contact with the substrate provides a stripping method of the photoresist. As said propylene glycol ether acetate, it is preferable to use propylene glycol monomethyl ether acetate.

According to the present invention, an inexpensive compound such as propylene glycol monomethyl ether acetate can be used as the main component of the thinner composition or a compound having a high composition ratio. Although the thinner compositions can be manufactured at a low price, the same or better photoresist stripping characteristics can be obtained as in the conventional thinner compositions. Therefore, the thinner compositions are economically very advantageous when used in the semiconductor industry that requires a recent cost reduction. Further, since the compounds constituting the thinner composition are environmentally friendly, they can actively cope with recent environmental problems.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

First, propylene glycol monomethyl ether acetate (PGMEA, hereinafter sometimes referred to as "PGMEA"), ethyl 3-ethoxy propionate and gamma- A first thinner composition composed of butyrolactone (Gamma-Butyro Lactone) will be described.

In the first thinner composition, when the content of the propylene glycol monomethyl ether acetate exceeds 80% by weight, the EBR characteristic for a specific photoresist is lowered, which is not preferable. In addition, if it is less than 50% by weight, the content of ethyl 3-ethoxy propionate is relatively increased, so that the solubility in the photoresist is lowered and the EBR characteristic for the specific photoresist is lowered, which is not preferable. Therefore, the content of the propylene glycol monomethyl ether acetate is 50 to 80% by weight, preferably 53 to 75% by weight.

When the content of the ethyl 3-ethoxy propionate (Ethyl (3-Ethoxy) Propyonate (EEP, hereinafter referred to as "EEP") is less than 10% by weight and the EBR characteristic is not good, and exceeds 45% by weight It is not preferable because the solubility to a specific photoresist decreases. Thus, the content of ethyl 3-ethoxy propionate is 10 to 45% by weight, preferably 12 to 30% by weight.

The first thinner composition also includes Gamma-Butyro Lactone (GBL, hereinafter sometimes referred to as "GBL"). The gamma-butyrolactone is known to have a good dissolving ability with respect to resins.

The PGMEA has physical properties of specific gravity of 0.968 at 25 ° C, viscosity of 1.3 cps at 25 ° C, boiling point at 145 to 146 ° C at atmospheric pressure, and flash point of 43 ° C. In particular, PGMEA is relatively inexpensive and has good wettability (wettability, spreadability on the substrate or reaction with photoresist), but when used alone, defects occur in the edge of the photoresist, especially in the EBR process.

When the content of gamma-butyrolactone is less than 1% by weight, the solubility of a specific photoresist decreases and the photoresist stripping property is not preferable, and the content of gamma-butyrolactone is more than 12% by weight. The manufacturing cost of the thinner composition is increased, which is not preferable. Thus, the content of gamma-butyrolactone is 1 to 12% by weight, preferably 2 to 10% by weight.

The thinner composition may further include a trace amount of a surfactant as necessary. Surfactants usable in the present invention include alkylbenzenesulfonates and alkali metal salts thereof, alkylated diphenyl disulfonates and alkali metal salts thereof, alkyl aryl sulfonates, alkali metal fluoroalkaline carboxylate salts, ammonium perfluoroalkyl Sulfonates, and the like. The role of the surfactant is to improve the wettability (WETTABILITY) and to mix each component of the thinner evenly. The content of the surfactant is preferably 1% by weight or less.

Next, Propylene Glycol Mono-methyl ether acetate, Propylene Glycol Mono-methyl ether and Ethyl (3-Ethoxy) Propyonate The thinner composition for stripping the second photoresist consisting of the following will be described.

The second thinner composition of the present invention contains propylene glycol monomethyl ether acetate as a main component. Description of the propylene glycol monomethyl ether acetate is as described above.

In the thinner composition, when the content of the propylene glycol monomethyl ether acetate is 80% by weight or more, the EBR characteristic is lowered. Therefore, the content of the propylene glycol monomethyl ether acetate is 40 to 80% by weight, preferably 40 to 70% by weight.

The second thinner composition of the present invention comprises ethylene 3-ethoxy propionate.

If the content of the ethylene 3-ethoxy propionate is less than 5% by weight, the EBR characteristic is lowered. If the content of the ethylene 3-ethoxy propionate is less than 45%, the solubility in the photoresist is lowered. Therefore, the content of ethyl 3-ethoxy propionate is 5 to 45% by weight, preferably 10 to 40% by weight, most preferably 20 to 30% by weight.

The second thinner composition of the present invention comprises propylene glycol monomethyl ether (PGME, hereinafter sometimes referred to as "PGME").

If the content of the propylene glycol monomethyl ether is more than 35% by weight or less than 5% by weight, the EBR characteristic for a specific photoresist is lowered, which is not preferable. Therefore, the content of the propylene glycol monomethyl ether is 5 to 35% by weight, preferably 10 to 30% by weight, most preferably 15 to 25% by weight.

And, it is preferable that the second thinner composition further contains a surfactant. The surfactant is the same as described above. The content of the surfactant is preferably 1% by weight or less.

The stripping method of the photoresist using the thinner compositions will be described.

EBR process

1 is a process diagram illustrating a method for stripping photoresist applied to a substrate edge and a back surface area using a thinner composition according to an embodiment of the present invention.

Referring to FIG. 1, a thinner composition composed of the PGMEA, GBL, and EEP or a thinner composition composed of the PGMEA, PGME, and EEP is prepared. (Step S10)

Next, a photoresist is applied onto the substrate. (Step S12) The application of the photoresist mainly uses a spin-coater. Thus, photoresist is applied to the substrate to be rotated by the spin-coater. Accordingly, the photoresist sprayed on the substrate is pushed to the edge of the substrate by centrifugal force and applied to the entire region of the substrate with a uniform thickness.

The photoresist pushes not only the edge portion of the substrate but also the back portion portion of the substrate by the centrifugal force. As such, the photoresist that is pushed to the edge and backside portions of the substrate and applied to the edges and backside of the substrate acts as a defect in subsequent processes.

Therefore, the thinner composition is brought into contact with the edge and the back surface of the substrate to which the photoresist is applied to strip the photoresist. (Step S14) The contact of the thinner composition may include a method of spraying the thinner composition on the substrate.

The method of spraying the thinner composition may be performed using a spin-chuck for rotating the substrate, a nozzle for spraying the thinner composition, or the like.

In this embodiment, a method of spraying the thinner composition using the rotary chuck and the nozzle will be described.

When spraying the thinner composition, the substrate is preferably subjected to a low speed rotation and a high speed rotation sequentially by the rotation-chuck.

First, the thinner composition is sprayed while rotating the photoresist-coated substrate at a relatively low speed. The thinner composition is sprayed to the edge and backside of the substrate for about 5-10 seconds, preferably 6 seconds, through the nozzle while rotating the substrate at a speed of, for example, 800 to 2,000 rpm. Then, the thinner composition sprayed on the rotating substrate strips and removes the photoresist unnecessarily applied to the edge and the backside of the substrate by centrifugal force.

Next, the substrate is spin-dried by rotating the substrate at a relatively high speed of 2,000 to 2,500 rpm. (Step S16) This spin dry step can be omitted if necessary.

In addition, other methods of spraying the thinner composition are as follows. After fixing the nozzle, there is a method of spraying the thinner composition to the edge of the substrate while rotating the substrate, and after fixing the substrate, spraying the thinner composition while moving the nozzle along the edge portion of the substrate There is a way. In addition, the method of spraying the thinner composition on the back surface of the substrate is similar to the method of spraying the thinner composition on the edge of the substrate using another nozzle. After that, the usual photo process, that is, photoresist baking, exposure and development process are performed.

Rework process

2 is a flowchart illustrating a method for stripping a photoresist applied to the entire surface of a substrate using a thinner composition according to an embodiment of the present invention.

First, if a defect occurs in a state in which the normal photo process, that is, the development process is completed, the rework process is performed.

Referring to FIG. 2, a thinner composition composed of the PGMEA, GBL, and EEP or a thinner composition composed of the PGMEA, PGME, and EEP is prepared. (Step S20)

Then, the thinner composition is contacted with a substrate on which the photoresist is applied, that is, a substrate for reworking for reuse, to strip the photoresist. The method of contacting the thinner composition may include dipping the substrate into the thinner composition contained in the bath, or spraying the thinner composition on the substrate using a spin-chuck and a nozzle.

This embodiment describes a method of spraying thinner composition onto a substrate using the rotation-chuck and nozzle.

First, the thinner composition is sprayed onto the substrate while rotating the substrate on which the photoresist is applied at a relatively low speed. (Step S22) Specifically, the thinner composition is sprayed on the substrate for about 10 to 20 seconds through the nozzle while rotating the substrate at a speed of 800 to 2,000 rpm. Then, the thinner composition sprayed on the rotating substrate is uniformly provided on the substrate by centrifugal force.

Then, the rotation of the substrate is temporarily stopped. (Step S24) The stop of the substrate is held for about 10 to 30 seconds. Then, the photoresist applied on the substrate is dissolved by the thinner composition sprayed on the substrate.

Next, the wafer is optionally spin-dried by rotating the substrate at a high speed of about 2,000 to 2,500 rpm. The spin dry may be omitted.

The substrate is then rotated at a relatively high speed to remove photoresist residue remaining on the substrate. Specifically, the thinner composition is sprayed on the substrate rotating at high speed while rotating the substrate at a speed of about 2000 to 2500 rpm for about 10 to 20 seconds. (Step S26) Then, the photoresist residue remaining on the said board | substrate is removed.

Then, the injection of the thinner composition to the substrate rotating at a high speed is stopped. Then, only the substrate continues to rotate at a high speed of 2000-2500 rpm. As a result, spin dry of the thinner composition injected onto the substrate is performed. (Step S28)

Subsequently, pure water is sprayed onto the substrate to clean the substrate, and the substrate is continuously rotated to spin dry. (Step S30)

Here, the steps S24, S26 and S30 may be omitted by the operator as an additional process.

Therefore, when stripping of the photoresist is performed through the above method, the substrate can be reused.

As such, when stripping the various photoresists, excellent stripping characteristics may be obtained even by using the thinner compositions. That is, the present invention does not affect the stripping properties of the photoresist despite the use of the low cost thinner composition.

Hereinafter, embodiments of the present invention will be described in detail.

Example 1

PGMEA, GBL and EEP were put into a container, and these were mixed to prepare a thinner composition. The thinner composition was adjusted so that the content of PGMEA was 73% by weight, the content of GBL was 2% by weight, and the content of EEP was 25% by weight. The viscosity of the obtained thinner composition was 1.3cp (measured in a 25 degreeC thermostat).

Example 2

PGMEA, GBL and EEP were put into a container, and these were mixed to prepare a thinner composition. The thinner composition was adjusted to have 54 wt% PGMEA, 36 wt% EEP, and 10 wt% GBL. The viscosity of the obtained thinner composition was 1.3cp (measured in a 25 degreeC thermostat).

Example 3

PGMEA, PGME and EEP were put into a container, and these were mixed to prepare a thinner composition. The thinner composition was adjusted to have 60 weight percent propylene glycol monomethyl ether acetate (PGMEA), 10 weight percent ethylene 3-ethoxy propionate (EEP) and 30 weight percent propylene glycol monomethyl ether. The viscosity of the thinner composition obtained was 1.4 cp (measured in a 25 ° C thermostat).

Example 4

PGMEA, PGME and EEP were put into a container, and these were mixed to prepare a thinner composition. The thinner composition was adjusted to have 50 wt% propylene glycol monomethyl ether acetate (PGMEA), 30 wt% ethylene 3-ethoxy propionate (EEP) and 20 wt% propylene glycol monomethyl ether. The viscosity of the thinner composition obtained was 1.4 cp (measured in a 25 ° C thermostat).

Example 5

PGMEA, PGME and EEP were put into a container, and these were mixed to prepare a thinner composition. The thinner composition was adjusted to have 50 wt% propylene glycol monomethyl ether acetate (PGMEA), 40 wt% ethylene 3-ethoxy propionate (EEP) and 10 wt% propylene glycol monomethyl ether. The viscosity of the thinner composition obtained was 1.4 cp (measured in a 25 ° C thermostat).

Comparative Example 1

The thinner composition was prepared by PGMEA alone. The viscosity of the thinner composition obtained was 1.3 cp (measured in a 25 ° C. thermostat).

Comparative Example 2

PGMEA and GBL were put in a container, and these were mixed to prepare a thinner composition. The thinner composition was adjusted to have 95% by weight of propylene glycol monomethyl ether acetate (PGMEA) and 5% by weight of gamma butyrolactone (GBL). The viscosity of the thinner composition obtained was 1.3 cp (measured in a 25 ° C. thermostat).

Comparative Example 3

PGMEA and EEP were put into a container, and these were mixed to prepare a thinner composition. The ratio of PGMEA: EEP in the thinner composition was adjusted to 80:20. The viscosity of the obtained thinner composition was 1.2-1.3 cp (measured in a 25 degreeC thermostat).

Comparative Example 4

PGMEA and PGME were put in a container, and these were mixed to prepare a thinner composition. The ratio of PGMEA: PGME in the thinner composition was adjusted to 80:20. The viscosity of the obtained thinner composition was 1.3-1.4 cp (measured in 25 degreeC thermostat).

Comparative Example 5

PGMEA and EL were put into a container, and these were mixed to prepare a thinner composition. The ratio of PGMEA: EL in the thinner composition was adjusted to 80:20. The viscosity of the thinner composition obtained was 1.4 cp (measured in a 25 ° C thermostat).

Comparative Example 6

PGMEA, GBL and EEP were put into a container, and these were mixed to prepare a thinner composition. The thinner composition was adjusted to have 38% by weight of propylene glycol monomethyl ether acetate (PGMEA), 60% by weight of ethylene 3-ethoxy propionate (EEP) and 2% by weight of gamma butyrolactone (GBL). The viscosity of the obtained thinner composition was 1.2-1.3 cp (measured in a 25 degreeC thermostat).

Comparative Example 7

EEP, EL, and GBL were put into a container, and these were mixed, and the thinner composition was prepared. The thinner composition was adjusted so that the content of the EEP was 75% by weight, the content of the EL was 20% by weight, and the content of the GBL was 5% by weight. The viscosity of the thinner composition obtained was 1.30 cps (measured in a 25 ° C thermostat).

Comparative Example 8

NBA and GBL were put into a container, and these were mixed, and the thinner composition was prepared. The ratio of NBA: GBL in the thinner composition was adjusted to 85: 5. The viscosity of the obtained thinner composition was 0.74 cps (measured in a 25 ° C thermostat).

Comparative Example 9

The thinner composition was prepared by EEP alone. The viscosity of the thinner composition obtained was 1.2 cp (measured in a 25 ° C thermostat).

Comparative Example 10

The thinner composition was prepared by PGME alone. The viscosity of the thinner composition obtained was 1.75 cps (measured in a 25 ° C thermostat).

Dissolution rate test by type of photoresist

The thinner compositions prepared in Examples 1 and 4 above were used to test dissolution rates for photoresists currently in use.

Test Example 1

After spin-coating a GS111M (product name) of Shipley Korea company (g.), Which is a g-line photoresist, on a substrate in an amount of about 1.5 cc, soft baking (heating at 90 ° C.) was performed. The thickness of the formed photoresist film was 12,200 GPa.

The substrate was then immersed in the thinner composition to sprip the photoresist and then the dissolution rate was observed. The observed dissolution rate was at least 12,000 kPa / sec.

Test Example 2

After spreading the MCPR-4100H (product name) of the Shipley Korea company (hingeuk), i-line photoresist, in an amount of about 1.5 cc, soft baking (heating at 90 ° C.) was performed. . The thickness of the formed photoresist film was 11,900 GPa.

The substrate was then immersed in the thinner composition to strip the photoresist, and then the dissolution rate was observed. The observed dissolution rate was over 3,000 Pa / sec.

Test Example 3

After spin-coating SAT-701 (product name) of a Tiokei Co., Ltd. (TOK company: Japan), which is an i-line photoresist, on a substrate, soft baking (heating at 90 ° C.) was performed. The thickness of the formed photoresist film was 9,700 GPa.

The substrate was then immersed in the thinner composition to strip the photoresist, and then the dissolution rate was observed. The observed dissolution rate was over 9,700 kPa / sec.

Test Example 4

After spin-coating SAT-668 (product name) of an i-line photoresist (TOK company (Japan)) as an amount of about 1.5 cc, soft baking (heating to 90 ° C.) was performed. The thickness of the formed photoresist film was 19,700 GPa.

The substrate was then immersed in the thinner composition to strip the photoresist, and then the dissolution rate was observed. The observed dissolution rate was over 19,000 kPa / sec.

Test Example 5

PFI-58A (product name) of Dongwoo Company (Korea), an i-line photoresist, was spin-coated on the substrate in an amount of about 1.5 cc, followed by soft baking (heating to 110 ° C.). The thickness of the formed photoresist film was 12,300 GPa.

The substrate was then immersed in the thinner composition to strip the photoresist, and then the dissolution rate was observed. The observed dissolution rate was over 12,200 kPa / sec.

Test Example 6

After spin-coating THMR-ip3100 (product name) of an i-line photoresist (TOK company (Japan)), which was an i-line photoresist, in an amount of about 1.5 cc, soft baking (heating to 110 ° C.) was performed. The thickness of the formed photoresist film was 14,400 GPa.

The substrate was then immersed in the thinner composition to strip the photoresist, and then the dissolution rate was observed. The observed dissolution rate was over 14,400 kPa / sec.

Test Example 7

After spin-coating SEPR-402 (product name) of Shin-Etsu Co., Ltd. (Shinetsu company, Japan), which is an ultraviolet photoresist, on a substrate, soft baking (heating at 100 ° C.) was performed. The thickness of the formed photoresist film was 10,300 GPa.

The substrate was then immersed in the thinner composition to strip the photoresist, and then the dissolution rate was observed. The observed dissolution rate was over 7,000 kPa / sec.

Test Example 8

After spin-coating SEPR-430 (product name) of Shin-Etsu Co., Ltd. (Shinetsu company, Japan), which is an ultraviolet photoresist, on a substrate, soft baking (heating at 100 ° C.) was performed. The thickness of the formed photoresist film was 5,700 GPa.

The substrate was then immersed in the thinner composition to strip the photoresist, and then the dissolution rate was observed. The observed dissolution rate was over 5,700 kPa / sec.

In Test Examples 1 to 8, the dissolution rates of various photoresists were observed using the thinner compositions prepared in Examples 1 and 4, and it can be seen that the dissolution rates were excellent for most photoresists. In addition, thinner compositions according to other examples showed similar results. Therefore, it can be seen that the thinner composition according to the present invention can be used to dissolve the photoresist applied on the wafer.

Solubility evaluation test by type of photoresist

The thinner compositions obtained in Examples 1 to 5 and Comparative Examples 1 to 10 were used to evaluate the solubility of dissolving the photoresist. The evaluation was performed by mixing the ratio of thinner: photoresist 1: 1 and 10: 1 to evaluate the degree of melting of the photoresist in the thinner.

Photoresist Type PR 1 PR 2 PR 3 PR 4 PR 5 PR 6 PR 7 PR 8 Example 1 0 0 0 0 0 0 0 0 Example 2 0 0 0 0 0 0 0 0 Example 3 0 0 0 0 0 0 0 0 Example 4 0 0 0 0 0 0 0 0 Example 5 0 △ 0 0 0 0 0 0 Comparative Example 1 0 0 0 0 0 0 0 0 Comparative Example 2 0 0 0 0 0 0 0 0 Comparative Example 3 0 0 0 0 0 0 0 0 Comparative Example 4 0 0 0 0 0 0 0 0 Comparative Example 5 0 0 0 0 0 0 0 0 Comparative Example 6 0 X 0 0 0 0 0 0 Comparative Example 7 0 △ 0 0 0 0 0 0 Comparative Example 8 X X 0 0 0 0 0 0 Comparative Example 9 X X 0 0 0 0 0 0 Comparative Example 10 0 0 0 0 0 0 0 0

Legend: 0 Good, △ Normal, × Bad

O: Photoresist melted well in thinner

(Triangle | delta): When a part of photoresist precipitates after elapse of time

X: When photoresist precipitates immediately after mixing with thinner

* PR 1 to 8 are the same photoresist as the photoresist used in Test Examples 1 to 8, respectively.

As can be seen from Table 1, when the thinner using the thinner composition obtained in Examples 1 to 5 of the present invention is mixed with the photoresist, it can be seen that it shows good dissolution characteristics.

Comparative Examples 6 to 9 have poor solubility in specific photoresists and thus cannot be used as photoresist spripping thinner compositions. However, other thinner compositions were good in terms of solubility.

Therefore, it can be seen that the thinner composition of the present invention can be used as a photoresist stripping thinner composition.

Evaluation of the EBR Process According to the Type of Photoresist

After using the thinner compositions obtained in Examples 1 to 5 and Comparative Examples 1 to 10 to perform the photoresist EBR process as described above, the degree of stripping of the photoresist was evaluated (EBR evaluation). For this EBR evaluation, photoresist contact was made using a method of spraying a thinner composition onto a substrate. The injection was performed using DNS nitrogen (N2) pressurized coater (Coater). At this time, the nitrogen pressure was 0.7 Kg / Cm 2, and the thinner composition was supplied for 6 seconds at a flow rate of 13 cc / min. The evaluation results are shown in Table 2 below.

Photoresist Type PR 1 PR 2 PR 3 PR 4 PR 5 PR 6 PR 7 PR 8 Example 1 0 0 0 0 0 0 0 0 Example 2 0 0 0 0 0 0 0 0 Example 3 △ △ 0 0 0 0 0 0 Example 4 △ △ 0 0 0 0 0 0 Example 5 △ △ 0 0 0 0 0 0 Comparative Example 1 △ X 0 - 0 0 0 △ Comparative Example 2 X X - - - △ 0 - Comparative Example 3 X △ 0 0 △ 0 0 0 Comparative Example 4 △ △ 0 0 0 0 X △ Comparative Example 5 X △ X X △ X △ 0 Comparative Example 6 △ △ △ △ △ 0 △ - Comparative Example 7 X △ 0 0 0 0 0 0 Comparative Example 8 X X X X X X X X Comparative Example 9 △ △ - - - 0 △ - Comparative Example 10 △ - - - - 0 X -

Legend: 0 Good, △ Normal, × Bad,-Not rated.

O: Residue is not present at the site where the EBR process is performed, and the boundary line of the photoresist after performing the EBR process (the boundary between the site where the EBR process is performed and the area where the process is not performed) is neatly formed.

(Triangle | delta): There is no residue in the site which performed the EBR process, but the photoresist boundary after the EBR process is dirty.

X: Residue in the part where EBR process was performed, and the photoresist boundary after the EBR process was dirty

* PR 1 to 8 are the same photoresist as the photoresist used in Test Examples 1 to 8, respectively.

As can be seen from Table 2, it can be seen that good stripping characteristics can be obtained when the EBR process is performed using the thinner compositions obtained in Examples 1 to 5 of the present invention.

In Comparative Examples 1 to 5, the EBR interface was bent or the residues were generated in the EBR interface for each specific photoresist.

In Comparative Example 6, a slight curvature occurred in the EBR interface for the I-line and the G-line.

In Comparative Example 7, the EBR interface was curved and widened for the G-line specific photoresist. However, most of the other photoresists show good results.

Comparative Example 8 showed that the photoresist residue remained after EBR because GBL did not completely complement the characteristics of NBA, which is highly permeable to PR.

In Comparative Example 9, the EBR boundary lines were not neat in I-line and G-line photoresists, and a lot of residues were generated.

In Comparative Example 10, residues were generated at the IBR line and the DUV photoresist where the EBR boundary and the EBR were performed.

The novel thinner compositions according to the invention exhibited good stripping properties for the various photoresist and EBR / REWORK processes used. In particular, the thinner composition contains a low-cost material such as propylene glycol monomethyl ether acetate as the main component of the stripper, and can increase the content of this component to the stripper. Therefore, the stripper composition can be produced at low cost, and excellent stripping properties can be secured for various photoresists. Since the stripper composition is environmentally friendly, it can be confirmed that it does not cause an environmental problem, thereby actively coping with an environmental problem to be caused later, and does not interfere with the lower layer.

The thinner composition of the present invention can obtain good stripping properties despite the low price, and thus can be widely used in the semiconductor industry.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the present invention without departing from the spirit and scope of the invention described in the claims below. I can understand that you can.

Claims (12)

Thinner composition for photoresist strips based on propylene glycol monomethyl ether acetate, ethyl 3-ethoxy propionate and gamma-butyrolactone. The method of claim 1, wherein the content of propylene glycol monomethyl ether acetate is 50 to 80% by weight, the content of ethyl 3-ethoxy propionate is 10 to 45% by weight and the gamma-butyrolactone (gamma- butyro lactone) is a thinner composition, characterized in that consisting of 1 to 12% by weight. The method of claim 2, wherein the content of propylene glycol monomethyl ether acetate is 53 to 75% by weight, the content of the ethyl 3-ethoxy propionate is 12 to 30% by weight and the gamma-butyrolactone (gamma- butyro lactone) is a thinner composition, characterized in that consisting of 2 to 10% by weight. The thinner composition according to claim 1, wherein the thinner composition further comprises a surfactant. Thinner composition for photoresist strips comprising propylene glycol monomethyl ether acetate, ethyl 3-ethoxy propionate and propylene glycol monomethyl ether. The method of claim 5, wherein the content of propylene glycol monomethyl ether acetate is 40 to 80% by weight, the content of ethyl 3-ethoxy propionate is 5 to 45% by weight and the content of propylene glycol monomethyl ether is Thinner composition, characterized in that consisting of 5 to 35% by weight. According to claim 6, wherein the content of the propylene glycol monomethyl ether acetate is 40 to 70% by weight, the content of the ethyl 3-ethoxy propionate is 10 to 40% by weight and the content of the propylene glycol monomethyl ether is A thinner composition, comprising 10 to 30% by weight. The thinner composition according to claim 5, wherein the thinner composition further comprises a surfactant. Thinner composition for photoresist strips consisting of propylene glycol monomethyl ether acetate, ethyl 3-ethoxy propionate and gamma-butyrolactone or propylene glycol monomethyl ether acetate, ethyl 3-ethoxy propionate and propylene glycol monomethyl Preparing a photoresist strip thinner composition composed of ether; Stripping the photoresist by contacting the thinner composition to the edge and / or backside of the substrate on which the photoresist is applied; And drying the thinner composition in contact with the substrate. Thinner composition for photoresist strips consisting of propylene glycol monomethyl ether acetate, ethyl 3-ethoxy propionate and gamma-butyrolactone or propylene glycol monomethyl ether acetate, ethyl 3-ethoxy propionate and propylene glycol monomethyl Preparing a photoresist strip thinner composition composed of ether; Spraying the thinner composition onto the substrate while rotating the substrate on which the photoresist is applied at a first speed; And Stripping method of the photoresist comprising the step of drying the thinner composition sprayed on the substrate. The method of claim 10, wherein after spraying the thinner composition onto the substrate, Temporarily stopping rotation of the substrate; And Spraying the thinner composition while rotating the substrate at a second speed; After the drying step, And further rinsing / drying the substrate with pure water. 12. The method of claim 11, wherein said first speed is slower than said second speed.