KR20220040841A - Method Of Manufactoring Eco-Friendly High-Density Wiper For Semiconductor Clean Room - Google Patents

Abstract

The present invention relates to a method for manufacturing an eco-friendly high-density wiper for a semiconductor manufacturing clean room, that performs a high shrinkage process without a need to use benzyl alcohol emulsion. According to the present invention, existing weight reduction division and high shrinkage processes are integrated, and benzyl alcohol-based emulsion is not used during the high shrinkage process, thereby resulting in excellent wiping performance of the manufactured wiper as well as the reduced nonvolatile residue (NVR). Therefore, the method for manufacturing an eco-friendly high-density wiper for a semiconductor manufacturing clean room is eco-friendly and enables energy and water to be reduced by about 50% and manufacturing cost to be reduced by 25% or more.

Description

Manufacturing method of eco-friendly high-density wiper for semiconductor manufacturing clean room {Method Of Manufactoring Eco-Friendly High-Density Wiper For Semiconductor Clean Room}

The present invention solves problems and environmental problems in semiconductor manufacturing due to non-volatile residue (NVR) by performing a high shrinkage process without using benzyl alcohol emulsion used in the high shrinkage process of microfiber wiper products used in semiconductor manufacturing lines. It relates to a method of manufacturing an eco-friendly high-density wiper for a semiconductor manufacturing clean room that can be solved.

Korea has the first and second largest companies in the global memory semiconductor market, and the combined market share of the two companies is 73% for DRAM and 46% for NAND flash as of 2018.

As the miniaturization of the semiconductor manufacturing process is accelerated, the possibility of defects occurring even with a small amount of impurities increases, so the importance of cleaning is increasing. Cleaning accounts for about 15% of the main semiconductor process and is a very important process that is directly related to product performance, reliability, and yield. is growing

Microfiber wiper products are a core product that directly affects semiconductor quality as a material used to clean from contaminants such as various residues and foreign substances generated in the semiconductor manufacturing process.

Microfibers manufactured by composite spinning of two-component polymers have an excellent decontamination mechanism even in minute curved areas that are difficult to remove due to a dramatic increase in surface area after the compounding process. A high shrinkage processing process using an alcohol emulsion and a high-performance wiper material using the same have been developed and used.

After Kanebo of Japan launched Verima X, a multi-split yarn in 1975, KB Siren developed and commercialized SAVINA MX, a cleanroom product, and SAVINA MX is a circular knitted fabric with multi-split yarns with fineness of 100d/50f and 40d/25f. It is widely used by manufacturing industrial high-clean wipers. Products produced by KB Siren are used as the best high-performance wipers in processes such as semiconductor/integrated circuit manufacturing and camera precision parts assembly.

These high-performance wiper products have been manufactured through high-shrinkage processing, which is reduced by immersion/moist heat treatment in high-concentration NaOH aqueous solution after pretreatment, and high-shrinkage through batch or continuous benzyl alcohol emulsion treatment. It has superior wiping properties compared to low-cost wipers, but as described above, a high-shrinkage process using benzyl alcohol is applied, so it exhibits a relatively high NVR. In particular, this high-shrink high-density wiper has a very dense structure once it is shrunk, so it is necessary to repeatedly perform water washing under very harsh conditions to discharge the residual substances inside, and it is difficult to completely remove it Many non-volatile residues (NVR, Non-Volatile Residue) are being detected.

The NVR is recognized as a core performance because the chemicals used during the wiper manufacturing process are not completely removed and can contaminate the semiconductor during wiping. Benzyl alcohol is mainly used as a preservative, but special attention is required in handling as it is a toxic substance known to cause allergies and have a risk of internal organ toxicity (infertility risk). In addition, environmental regulations around the world are getting stronger and eco-friendly processes are being emphasized, so the application of eco-friendly manufacturing processes is urgently required.

Republic of Korea Patent Publication No. 10-2010-0032002 (published on March 25, 2010)

Therefore, in the present invention, in manufacturing a high-density wiper applicable to a semiconductor manufacturing process, which is a clean environment with extremely few particles, the generation of non-volatile residues (NVR) is minimized and an eco-friendly high-density wiper for a semiconductor manufacturing clean room that does not use a harmful process It is a technical task to provide a manufacturing method.

Therefore, according to the present invention, the DTY processing yarn of the NP split composite yarn consisting of a polyamide part and a polyester part is supplied to a double-sided circular knitting machine and knitted, and then refined at 80 to 90 ° C. There is provided a method of manufacturing an eco-friendly high-density wiper for a semiconductor manufacturing clean room, characterized in that heat setting is performed at 180 to 195° C. and 30 to 40 m/min after high shrinkage processing.

Hereinafter, the present invention will be described in more detail.

The present invention solves problems and environmental problems in semiconductor manufacturing due to non-volatile residue (NVR) by performing a high shrinkage process without using benzyl alcohol emulsion used in the high shrinkage process of microfiber wiper products used in semiconductor manufacturing lines. It relates to a method of manufacturing an eco-friendly high-density wiper for a semiconductor manufacturing clean room that can be solved.

The manufacturing method of the eco-friendly high-density wiper for a semiconductor manufacturing clean room of the present invention is largely composed of yarn DTY processing, knitting, refining, weight reduction division and high shrinkage processing in the order.

The yarn used in the present invention is an NP split composite yarn composed of a polyamide part and a polyester part. TPA and IPA (Isophthalic acid) in which the polyester part has a weight ratio of 80:20 to 90:10 are reacted with EG (Ethylene Glycol) NP split composite yarn, which is a high-shrink polyester, is used.

General polyester is a condensate of TPA (Terephthalic acid) and EG (Ethylene Glycol), and it is known that TPA mainly contributes to the formation of a crystalline region and EG contributes to the formation of an amorphous region. In the present invention, in the polymerization process, TPA and Isophthalic acid (IPA) are supplied in a weight ratio of 80:20 to 90:10 and reacted with EG to be copolymerized. becomes an ester.

NP split composite yarn is manufactured by composite spinning of such high shrinkage polyester and nylon resin in a conventional way. This high shrinkage NP composite split yarn has a very high density through shrinkage processing and thus has dimensional stability while reducing the specific surface area of the split yarn. It has excellent wiping properties due to the increase.

The high shrinkage NP composite split yarn prepared in this way has the advantage of being able to have high shrinkage without using benzyl alcohol emulsion through improved heat shrinkage by adding IPA in the polymerization process to increase the amorphous region of the polyester part.

In the present invention, rather than using the NP composite split yarn as it is, twist and untwist while applying heat to the NP composite split yarn to give bulkiness to the filament yarn and at the same time to promote the initial split at the NP interface. It is made and used for weaving or knitting.

This DTY processing worker passes the NP split composite yarn through the first feed roller and heat-treats it in the first heater at 140 to 160 ° C. After stretching at a draw ratio of 1.10 to 1.35 while making it, it is entangled with an air pressure of 13 to 16 kgf/cm 2 and wound up at a yarn speed of 400 to 550 m/min.

When the temperature of the first heater is less than 140 ℃, the bulkiness of the false twisted yarn is deteriorated, and when it is more than 160 ℃, there may be problems in that untwisted or fusion occurs.

After performing the false twist, it passes through the second feed roller, and the filament is drawn by using the speed difference between the first feed roller and the second feed roller. At this time, it is preferable that the draw ratio is 1.10 to 1.35 times. If the draw ratio is less than 1.10 times, untwisted occurs and the uniformity of the false twisted yarn is lowered. cause the problems of

After the stretching, it is entangled in the interlace nozzle and wound with a winding roller at a yarn speed of 400 to 550 m/min to complete the DTY processing. The pressure is preferably 13-16kgf/cm2. If the pressure exceeds 16kgf/cm2, interlacing marks may occur on the surface of the fabric after knitting. can

The DTY processing of the NP split composite yarn prepared in this way is supplied to a double-sided circular knitting machine and knitted.

After knitting, refining at 80~90℃, reducing division and high shrinkage under 100~130℃, alkali solution, heat setting at 180~195℃, 30~40m/min, eco-friendly high-density wiper for clean room of the present invention will be manufactured

The refining process is carried out at 80~90℃ for 15~20 minutes, and the reduction division process and the high shrinkage process are performed at 100~130℃, under an alkali (NaOH) solution. The heat setting is 180~195℃, 30~40m/min, and it is allowed to stay in the heat setting chamber for 50~60 seconds.

It is preferable that the degree of division is 80 to 90%, and the shrinkage is 20 to 30% during the division and high shrinkage processing, and the shape stability and wiping property of the high-density wiper are preferable.

The high shrinkage processing of the microfiber wiper using the existing NP split yarn used a benzyl alcohol-based emulsion for structural modification of the synthetic fiber polymer chain. It has a fatal disadvantage that it is difficult to treat, so conversion to an environmentally friendly process is urgently required.

In addition, the existing microfiber wipers using NP split yarns have superior wiping properties compared to general inexpensive wipers, but as described above, a high shrinkage process using benzyl alcohol is applied, thereby exhibiting a relatively high NVR. This high-shrink high-density wiper has a very dense structure once it is shrunk, so it is necessary to repeatedly perform water washing under very severe conditions in order to discharge the residual material inside. is manufactured by adding IPA in the polymerization process to increase the amorphous region of the polyester part, and through improved heat shrinkability, high shrinkage is possible without using benzyl alcohol emulsion. In addition, the washing process can be simplified, which is very advantageous in terms of cost.

Therefore, according to the present invention, while wiping performance is excellent, the existing reduction division and high shrinkage processes are integrated, and the benzyl alcohol-based emulsion is not used during the high shrinkage process, so the NVR is reduced and eco-friendly, and energy/water is about 50%, It is possible to provide a manufacturing method of an eco-friendly high-density wiper for a semiconductor manufacturing clean room that can reduce manufacturing cost by about 25% or more.

1 is a surface micrograph of an eco-friendly high-density wiper for a semiconductor manufacturing clean room manufactured according to Example 1 of the present invention;
2 is a cross-sectional micrograph of an eco-friendly high-density wiper for a semiconductor manufacturing clean room manufactured according to Example 1 of the present invention.

In the following embodiment, a non-limiting example of manufacturing an eco-friendly high-density wiper for a semiconductor manufacturing clean room of the present invention is given.

[Example 1]

NP composite split yarn (75D/48f, 7-split, PET:Nylon= 70:30) was subjected to DTY processing according to the conditions in Table 1 below, and then supplied to a double-sided circular knitting machine and knitted with an interlock structure (32G).

Refining was carried out at 90° C. x 15 min, and reduction division/high shrinkage (liquid flow rapid) was performed at 130° C. for 20 min at a concentration of 3.0% NaOH, so that the division degree was 80% and the shrinkage rate was 20%. The heat setting conditions were 185°C x 40 m/min.

fair factor control condition YS (fire speed) 450m/min DR (draw ratio) 1.12 Disc conf. 1 - 6 - 1 (52 × 3T × 14.45) HT1 (heater temperature) 145℃ DS/YS (disk speed/dead speed) 1.40 OF1 (Correction OF) 4.5% OF2 (winding OF) 5.5% T1 (false tension) 25gf T2 (disengagement tension) 20gf T3 (winding tension) 3.5 gf air nozzle 1.4Φ air pressure 15kgf/cm2

[Comparative Example 1]

General NP split yarn to double-sided circular knitting machine Supply and knit with an interlock structure (32G), scouring at 90℃ x 15min, reducing division at 100℃ for 30 minutes under NaOH 3.0% concentration, high shrinkage at 130℃ for 20min using benzyl alcohol emulsion, splitting degree 80 %, the shrinkage rate was 20%. Heat setting conditions were performed under the conditions of 185°C x 40 m/min.

The results of physical property analysis of the wipers of Example 1 and Comparative Example 1 are shown in Table 2 below.

division unit Example 1 Comparative Example 1 Assessment Methods Shrinkage (width direction) % 20 20 KS K ISO 22198 Apparent density g/cm ³ 0.30 0.30 KS K 0642 8.3.2 split view % 80 80 microscopy
- Measure the number of divided yarns in the fabric state
- Test results in the presence of external experts RoHS - PASS - Quantitative analysis through GC, LC, ICP, etc.
- Heavy metals are reduced in molecular weight using acids and quantitatively analyzed using a spectrometer.
-The compound is extracted using an extractor and then quantitatively analyzed using a spectrometer. REACH - PASS - NVR IPA g/m ² 0.013 0.427 Precisely measure the weight of one wiper to 5 significant digits.
After stirring on an orbital shaker containing 100 ml of solvent
Put the stirring solution in a 250ml round flask equipped with a reflux condensor and use a hot plate to concentrate the solvent to 10ml or less.
This concentrate is placed in a weighed aluminum dish and
Put it in an oven at 200℃, evaporate the solvent, and then measure the weight. DIW g/m ² 0.001 0.001 absorption
hour horizontal sec 7 41 Engraved using a rubber seal with a diameter of 6 cm in the center of the specimen.
Measure the time it takes for water to reach the engraved part after adding 1ml of water using an auto dispenser to the center of the specimen 1cm above it. vertical sec 39 304 Cut the specimen to 2 cm in width and 5 cm in length, and mark the cut specimen with a line at 1 cm and 4 cm positions.
Immerse a 0.5 cm part of the specimen in water and measure the time from the time it passes 1 cm to the time it passes 4 cm. absorption ml/g 3.06 1.63 Weigh the wipers
Immerse the wiper in a water bath containing DI Water for 30 seconds.
Take out the wiper that has been absorbed and take it out naturally for 30 seconds
After dehydrating the water, measure the weight of the dehydrated specimen to 2 decimal places. Particles >0.5μm ea/㎡ 14x10 ⁶ 13x10 ⁶ Put one wiper into a Sus Tray containing 100ml of DI Water and stir at 100rpm for 3 minutes using a Biaxial Shaker.
Measure and record the number of particles per ml using the Liquid Particle Counter of this solution. Lint
(Fiber) >100μm ea/sh 24 53 Put 1 wiper in the Sus Tray containing 100ml of DI Water.
and stirred for 3 minutes at 100rpm using an Orbital Shaker.
After removing the wiper with tweezers, use the stirred DI Water.
Filtration using a filter device equipped with filter paper.
After drying the filtered paper, record the number of lints over 100 micrometers using a microscope. >300μm ea/sh 17 22

Claims (4)

DTY processing yarn of NP split composite yarn consisting of polyamide part and high shrinkage polyester part is supplied to a double-sided circular knitting machine and knitted, then refined at 80~90℃, reduced division and high shrinkage processing at 100~130℃ under alkaline solution. and then heat-setting at 180-195°C and 30-40 m/min. The method of claim 1,
The polyester part of the NP split composite yarn is a high-shrinkage polyester made by reacting TPA and IPA (Isophthalic acid) with a weight ratio of 80:20 to 90:10 with EG (Ethylene Glycol). A method of manufacturing a wiper. The method of claim 1,
The DTY processing worker of the NP split composite yarn passes the NP split composite yarn through the first feed roller and heat-treats it in the first heater at 140 ~ 160 ° C. A method of manufacturing an eco-friendly high-density wiper for a semiconductor manufacturing clean room, characterized in that it is a DTY processing worker that is stretched at a draw ratio of 1.10 to 1.35 while passing through a roller, entangled at an air pressure of 13 to 16 kgf/cm2, and then wound at a yarn speed of 400 to 550 m/min. . The method of claim 1,
The method of manufacturing an eco-friendly high-density wiper for a semiconductor manufacturing clean room, characterized in that the degree of division is 80 to 90% and the shrinkage is 20 to 30% during reduction division and high shrinkage processing under the alkali solution.

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