KR0178680B1 - Photoresist stripper composition and methdo for manufactaring semiconductor devcie using the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-toxic photoresist stripping composition for semiconductor manufacturing, which has excellent solubility in photoresists in a semiconductor device manufacturing process and has low volatility and low flammability.

The present invention comprises 90 to 60% by weight of ethyl lactate (Ethyl Lactate) and 10 to 40% by weight of gamma-butyrolactone (v-Butyro Lactone), wherein ethyl lactate or gamma-butyrolactone is All of the pure grade of semiconductor grade can be selected and used, and the filtered to 0.2 μm level can be used in VLSI grade.

Accordingly, the non-toxic photoresist stripping composition for semiconductor manufacturing according to the present invention exhibits low solubility, low flammability and non-toxicity while having excellent solubility for commercially used photoresists, and particularly excellent edge beads for photoresists. It has the effect of providing rinse properties.

Description

Photoresist stripping composition for semiconductor device manufacturing and method of manufacturing semiconductor device using same

1 is a graph showing the evaporation amount with respect to the time of each of the components constituting the photoresist stripping composition according to the present invention.

2 is a graph showing the amount of evaporation versus time according to the mixing ratio of the photoresist stripping composition according to the present invention.

3 is a graph showing the swelling degree of the synthetic resin specimens to the ethyl lactate of the components constituting the photoresist stripping composition according to the present invention.

4 is a graph showing the swelling degree of the synthetic resin specimens for gamma-butyrolactone among the components constituting the photoresist stripping composition according to the present invention.

5 (a) to 5 (c) are photographs taken with an optical microscope of a photoresist coating state after edge bead rinsing on a wafer on which photoresist is applied.

The present invention relates to a photoresist stripping composition suitable for use in a semiconductor device manufacturing process, and more particularly, to a non-toxic photoresist stripping composition for manufacturing a semiconductor device having excellent solubility in photoresist and having low volatility and low flammability. It is about.

In general, organic solvents called thinners have strong volatility, and are widely used as chemicals for diluting and dissolving and removing organic substances such as paints, enamels, and photoresists. Esters such as ether acetate, butyl acetate, methyl ethyl ketone, 1-butanol, toluene, xylene and the like, and solvents in which a suitable mixture of low boiling point and medium boiling point to high boiling point are used. Although a petroleum solvent of 240 ° C. is used, it is composed of solvents having high flammability, high volatility, and high risk to humans or the environment, and is easily volatilized to the atmosphere, and it is known to show toxicity when inhaling the vapor.

In particular, as thinners in the semiconductor manufacturing process, ethylene glycol monoethylether acetate (ECA) or propylene glycol monomethylether acetate (PGMEA) is generally used as photoresist. It has been used in a large amount for removal, and they are also highly volatile and flammable, and are known to be toxic to humans such as leukopenia and fetal abortion at inhalation.

In some cases, ethyl lactate (EL; ethyl lactate) alone was used. However, since ethyl lactate exhibits a very low solubility in dissolving photoresist, ethyl lactate alone can be used to remove photoresist by simple injection, in particular, Since the speed was so low that the rinsing work near the edge was almost impossible, there was a problem of lowering overall work efficiency.

Therefore, on the one hand, an increase in dissolving power to organic materials, in particular photoresist to be dissolved and removed, an increase in edge bead rinse (EBR) treatment characteristics, an improvement in cross section of the photoresist after edge bead rinse treatment, and volatilization amount On the other hand, the development of a safe thinner having improved thinner properties for semiconductor manufacturing in terms of reduction of the amount of the human body and having little toxicity to the human body is actively required.

In addition, organic solvents generally have a characteristic smell (odor), which is due to the volatility of the solvent itself, the volatilized solvent molecules remain in the atmosphere in the workplace performing the production process, etc., inhalation due to worker breathing In particular, in the case of an organic solvent having a low flash point, it may be in a state of being mixed with oxygen in the atmosphere and then exploded mainly due to an electric shock or a spark.

On the other hand, Japanese Patent Application Laid-Open No. 6-212193 uses a conventional general photoresist stripping agent to remove residues of photoresist and stripping agent remaining on the substrate when the photoresist applied to the substrate is removed in the micropattern forming process. Although a detergent for removing a photoresist release agent containing an lactic acid alkyl ester is described, it is recommended that the photoresist release agent be used once to reconsider the photoresist on the substrate, thereby shortening the cleaning process of removing residues remaining on the substrate. It is nothing but content.

Accordingly, an object of the present invention is to provide a non-toxic photoresist stripping composition for semiconductor production having excellent solubility in photoresist and having low volatility and low flammability.

In addition, another object of the present invention is improved thinner properties for semiconductor manufacturing in terms of increasing dissolving power to photoresist, increasing edge bead rinse treatment characteristics, improving the cross-section of the photoresist after edge bead rinse treatment, and reducing the volatilization amount. To provide a non-toxic photoresist stripping composition for manufacturing a semiconductor having.

Non-toxic photoresist stripping composition for manufacturing a semiconductor according to the present invention for achieving the above object is made by mixing 90 to 60% by weight of ethyl lactate and 10 to 40% by weight of gamma-butyrolactone.

Hereinafter, a non-toxic photoresist stripping composition for manufacturing a semiconductor of the present invention will be described in detail with reference to specific examples.

Non-toxic photoresist stripping composition for manufacturing a semiconductor according to the present invention is made by mixing 90 to 60% by weight of ethyl lactate and 10 to 40% by weight of gamma-butyrolactone (v-Butyro Lactone). Ethyl lactate or gamma-butyrolactone can be used in the most pure grade of semiconductor grade, and in the VLSI grade, filtered to 02.㎛ level.

The non-toxic photoresist stripping composition for semiconductor production according to the present invention is particularly preferably made by mixing 85 to 75% by weight of ethyl lactate and 15 to 25% by weight of gamma-butyrolactone.

Among the two components constituting the photoresist stripping composition of the present invention, the ethylate, which is used in a larger amount, has been recognized by the US Food and Drug Administration (FDA), and is currently used as a food additive, and is stable to the human body. In the toxicology test, 50% lethal dose due to oral administration to mice shows LD ₅₀ (mouser) = 2.5 g / kg, and is rapidly decomposed into lactic acid (lactic acid) and ethanol by enzymatic activity. The physical properties of the ethyl lactate density 0.97g / cm ³ , breaking point 156 ℃, the firing point (measured in a closed cup method) 52 ℃, viscosity (at 25 ℃) 2.7 cps (centipoise) to be.

In addition, the gamma-butyrolactone is known as a solvent of synthetic resin, has a high flash point, relatively stable as a solvent, 50% lethal dose due to oral administration to rats in the toxicity test LD ₅₀ (Rat) = 1.5g / kg, and skin contact test and intake experiment over 3 months has proven to be safe enough to show no poisoning in the human body. The physical properties of gamma-butyrolactone are density 1.128 g / cm 3, boiling point 204 ° C., flash point (measured in a closed cup method), 100 ° C., and viscosity (at 25 ° C.) 1.7 cps (centipoise) .

In particular, the physical properties of the mixed solution of 80% by weight of ethyl lactate and 20% by weight of gamma-butyrolactone have a density of 1.052 g / cm 3, a boiling point of 160 ° C., a flash point (measured by a closed cup method) 96 to The photoresist stripping composition of the present invention, which is measured at 98 ° C. and a viscosity (at 25 ° C.) of 2.25 cps (centipoise), is composed of a mixed solution. The two components which are constituents thereof are ethyl lactate and gamma-buty. It has been confirmed that the intermediate values of the rock lactone can be seen that it is possible to prepare a photoresist stripping composition having suitable physical properties depending on the conditions of use.

Examples and comparative examples of the present invention will be described below, but the following examples are intended to illustrate the present invention and should not be understood as limiting the scope of the present invention.

[Examples 1 to 4]

According to the present invention, the weight ratio of ethyl lactate (EL) and gamma-butyrolactone (GBL) is 90:10 (Example 1), 80:20 (Example 2), 70:30 (Example 3) and 60:40 (Example 4) was uniformly mixed, and the dissolution rate with respect to the photoresist, the volatilization amount with respect to the organic solvent, the corrosiveness with respect to the cleaning liquid supply apparatuses, and the processing cross section after the edge bead rinse treatment were evaluated.

[Comparative Examples 1 to 4]

Propylene glycol monomethyl ether acetate (PGMEA) (Comparative Example 1), ethylene glycol monoethyl ether (ECA) (Comparative Example 2), ethyl lactate (EL) (Comparative Example 3) alone and with ethyl lactate When gamma-butyrolactone was mixed at a weight ratio of 95: 5 (Comparative Example 4), the same evaluation as in the above example was performed.

[Dissolution Rate for Photoresist]

Photoresist stripping of the present invention with respect to S01A9 (SS01A9; Sumitomo Chemical Company Limited) and MCPI-I7010N (MCPR-i7010N; Mitsubishi) among commercially available photoresists The dissolution rate of the photoresist using the composition was measured. The experimental conditions were applied to the photoresist on the silicon wafer for semiconductor fabrication by applying the thickness S01 01 9 to 15,000 kPa (angstrom) and MC-I7010 yen to 14,000 kPa, respectively, soft-baking at 150 ℃ for 120 seconds BPC) and APC (APC; Model-790 manufactured by LJ C., Japan) were used as a measuring device, and propylene glycol monomethyl ether acetate (PGMEA) (compared to the conventional organic solvent as a solvent for rinsing the photoresist) was compared. Example 1), a photoresist stripping composition according to the present invention in which 80 g of ethylene glycol monoethyl ether acetate (ECA) (Comparative Example 2) and 20 g of ethyl lactate (EL) and 20 g of gamma-butyrolactone (GBL) were mixed (Example Solubility was measured for 2), and the results are shown in Table 1.

As shown in Table 1, the photoresist stripping composition according to the present invention has a significantly higher solubility compared to the conventional organic solvent propylene glycol monomethyl ether acetate (PGMEA), ethylene glycol monoethyl ether acetate (ECA) It can be seen that it has a higher solubility than).

In particular, the change in the dissolution rate of the photoresist stripping composition consisting of ethyl lactate alone or a mixture of ethyl lactate and gamma-butyrolactone was measured, and DS-200 (DSAM-200) as a photoresist was measured. The solubility was measured under the same conditions as described above except that the coating was carried out at a thickness of 12,250 kPa, 15,000 kPa and 20,600 kPa, and soft baked at 100 ° C. for 90 seconds, and the results are shown in Table 2.

As shown in Table 2, in the photoresist stripping composition according to the present invention, it was confirmed that the dissolution rate for the photoresist increased and decreased with increasing the content of gamma-butyrolactone. It can be seen that the increase significantly.

[Evaluation of Volatilization of Organic Solvents]

Representative solvents used for dissolving photoresist at room temperature (25 ° C.) under normal atmospheric pressure and the components of the photoresist stripping composition according to the present invention were measured, respectively. 1 is shown.

As shown in Table 3, when the evaporation amount is arranged in the order of increasing evaporation amount, it can be seen that the evaporation amount is decreased in the order of propylene glycol monomethyl ether acetate >> ethylene glycol monoethyl ether acetate ethyl lactate >> gamma-butyrolactone, and the present invention. Ethyl lactate and gamma-butyrolactone used in the photoresist stripping composition according to the present invention were compared with ethylene glycol monoethyl ether acetate or propylene glycol monomethyl ether acetate, which are used as conventional organic solvents even when each is present alone. It can be seen that the evaporation amount is small, in particular, gamma butyrolactone has a significantly lower evaporation rate than other organic solvents. However, although the evaporation amount (-0.14) 2 hours after the start of evaporation in the evaporation experiment shows a much higher value than the evaporation amount (-0.07) after 6 hours from the start of evaporation, this is considered to be an experimental error.

In addition, the evaporation amount of the photoresist stripping composition itself according to the present invention was measured at different mixing ratios, and the results are shown in Table 4 and FIG. 2.

As shown in Table 3, in the organic solvent formed by the mixture of ethyl lactate and gamma-butyrolactone, it can be seen that as the content of gamma-butyrolactone increases, the amount of evaporation decreases. When the content exceeds 20% by weight it can be seen that the degree of reduction of the evaporation amount does not vary significantly. Such a decrease in evaporation amount reduces the remaining amount of volatilized solvent molecules remaining in the atmosphere in the workplace performing the production process, etc., thereby reducing the inhalation amount due to the worker's breathing, as well as the risk of explosion. .

Infringement of Supply Units

In order to use the organic solvent in the automatic feeder, connect the feeders to each other in the feeder to check the chemical stability of the connection pipe or elastic O-ring. The resin specimens constituting the O-ring used for sealing are immersed in ethyl lactate and gamma-butyrolactone for at least 150 hours, thereby reducing the swelling ratio of the synthetic resin over time. Tate) and 4 (gamma-butyrolactone) graphically.

The synthetic resins having elasticity such as Viton, silicon resin, EPR, and Kaletz, which are measured above, are widely used in the manufacture of organic compound supply pipes or connecting O-rings, and the like. Those skilled in the art can be easily understood as well as those that can be purchased and used commercially.

As shown in FIG. 3, it can be seen that Viton is significantly swollen with respect to ethyl lactate as an organic solvent regardless of the purchase source, and it is stable because it hardly causes swelling with other silicone resins, EPR, and Kaletz. And it was found.

In addition, as shown in FIG. 4, it can be seen that the viton swells considerably regardless of the purchase source for gamma-butyrolactone as an organic solvent, and almost swells to other silicone resins, EPR and Kaletz. It did not cause a stable.

From the above results, the physical properties of the photoresist stripping composition according to the present invention are hardly changed. Therefore, synthetic resins having elasticity such as silicon, EPR, and Kaletz, except Viton, and organic compound supply pipes made thereof It can be used stably for an o-ring for connection or the like.

[Processing section after edge bead rinse treatment]

An organic solvent was used to test the degree of rinse on the photoresist-coated wafer and the type of cross section after edge bead rinse.

Edge bead rinsing is an important process of rinsing and removing unnecessary photoresist applied to the edge or side of the wafer on which photoresist is applied, especially in semiconductor manufacturing process. It is necessary to remove the photoresist uniformly and completely. The experiment was carried out as follows to determine the rinse characteristics of the photoresist.

Experimental conditions for the rinsing characteristics of the edge bead rinse were SS01A9 (Sumitomo Chemical Company Limited), TSM-i500 (TSMR-i500; Tokyo Oka Kogyo) and MCPRi7010N (MCPRi7010N) using a photoresist, S01A9 has a film thickness of 10,500Å, TSM-I500 has 16,300Å, and MRPI7010 yen has 25,000 The rinse characteristics of the wafers, which were each coated with a thin film and soft baked at 107 ° C. for 60 seconds, were investigated. In Example 2 of the present invention, 80 g of ethyl lactate and 20 g of gamma-butyrolactone were mixed while rotating the wafer at 3,000 rpm. The photoresist stripping composition was sprayed through the nozzle at a spray pressure of 0.6 kg to investigate the rinsing characteristics, and the results are shown in FIG. 5 (a) (S01). 9), the 5 (b) also (tieseuem Al-eye 500) and a 5 (c) Figure (indicated by 10-fold-up photographing the surface with a light microscope as shown in the 7010 yen MC PR child).

As can be seen from the optical micrographs of FIGS. 5 (a) to 5 (c), it can be seen that the photoresist stripping composition according to the present invention exhibits extremely excellent liniarity of the treated cross section. Thus, it has been found to be suitable for use for rinsing photoresist on wafers.

As specifically shown in each of Examples 1 to 4, the non-toxic photoresist stripping composition for manufacturing a semiconductor according to the present invention has low solubility and low volatility with respect to photoresists used commercially. It provides an effect that shows flammability and nontoxicity.

In addition, the non-toxic photoresist thin material for manufacturing a semiconductor according to the present invention has excellent edge bead rinsing properties with respect to commercially used photoresists, and is widely used in the manufacture of organic compound supply pipes or O-rings for connection. It can be applied to semiconductor manufacturing process by not swelling or physically or chemically modifying synthetic resins having elasticity such as silicon resin, EPR, and Kaletz, and providing excellent photoresist rinsing effect. Although the present invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that various modified light modifications are possible within the technical scope of the present invention, and such modifications and modifications belong to the appended claims.

Claims (3)

A non-toxic photoresist stripping composition for manufacturing a semiconductor device, characterized by mixing 90 to 60% by weight of ethyl lactate and 10 to 40% by weight of gamma-butyrolactone. The non-toxic photoresist stripping composition according to claim 1, wherein the ethyl lactate is mixed with 85 to 75 wt% and the gamma-butyrolactone 15 to 25 wt%. And removing the photoresist by using a photoresist stripping composition formed by mixing 90 to 60 wt% ethyl lactate and 10 to 40 wt% gamma-butyrolactone.