Preparation method of wet electronic chemical dip tube

Abstract

The invention discloses a wet electronic chemical dip tube and a preparation method thereof, and belongs to the field of application of high-cleanliness plastic products and wet electronic chemicals. The core of the method is that three technologies of production raw material formula development, key part transformation and process optimization are realized synergistically. A production formula of a high-purity high-density polyethylene raw material is developed, and the high-purity high-density polyethylene raw material is subjected to cloth bag dust removal and metal impurity separation treatment and is conveyed to a thousand-level dust-free workshop in a closed manner through a central feeding system; a special treatment fluorine-coated screw is adopted, the production process flow and process control are optimized, and ultrasonic cleaning post-treatment is combined, so that a complete and clean production system is constructed. The prepared high-cleanliness dip tube has low metal ion and particulate matter precipitation, and the cleanliness of the product meets the use requirement of the semiconductor industry.

Description

Technical Field

[0001] The present invention belongs to the field of ultra-clean plastic products and the application of wet electronic chemicals, and relates to a wet electronic chemical absorbent tube and a preparation method thereof. Background Art

[0002] As the "process blood" of the electronic manufacturing industrial chain, wet electronic chemicals are the core supporting materials for strategic industries such as semiconductor chips, display panels, high-efficiency photovoltaic modules, and advanced integrated circuit packaging. In the manufacturing of nano-scale electronic components, it plays a functional medium role in key processes such as wafer surface cleaning, photoresist development, dielectric layer etching, and metal interconnect layer treatment. With the iteration of semiconductor processes to below 3nm and the development of display panels towards ultra-thin flexibility, semiconductor manufacturers at home and abroad are gradually increasing their requirements for purity indicators such as metal impurities and particle size in wet electronic chemicals.

[0003] In the production and transportation system of wet electronic chemicals, a high-purity absorbent tube is a key component to ensure zero-pollution transmission of ultra-pure liquid media, and its performance has a decisive impact on the yield of precision processes such as semiconductor wafer manufacturing and flat panel display etching. However, traditional ordinary plastic products have many defects, such as insufficient cleanliness of production raw materials, ordinary production workshop environment, and high metal precipitation from processing equipment, resulting in their inability to meet the strict requirements for the production and transportation of wet electronic chemicals for semiconductors. The high-purity absorbent tube produced by the present invention fundamentally solves the above problems by optimizing key links such as raw material selection, production environment, and process. In terms of raw materials, high-density polyethylene is selected as the main raw material. This material has become an ideal material for the production of high-purity absorbent tubes at present due to its excellent high cleanliness, outstanding chemical corrosion resistance, and diverse molding methods. During the production process, injection molding and extrusion molding processes are used to ensure the molding accuracy and quality stability of the product. At the same time, the entire production process is carried out in a dust-free room environment, and extremely strict requirements are put forward for the cleanliness of raw material treatment, production process optimization, production water, and gas, thereby minimizing the pollution risk during the production process. Based on the above production process control, the high-purity absorbent tube produced by the present invention can meet the key requirements such as low impurity precipitation and good chemical resistance during the liquid pumping process of wet electronic chemicals.

[0004] In the field of wet electronic chemicals for semiconductors, the production technology of high-purity absorbent tubes is currently still monopolized by foreign countries. To achieve the domestic substitution of the transportation system of wet electronic chemicals, the raw materials for semiconductor production, and with the continuous improvement of semiconductor processes and the increasing requirements for the purity of wet electronic chemicals, developing a preparation technology for absorbent tubes with high cleanliness, good chemical resistance, and excellent structural strength has become an urgent need to break through the bottleneck of semiconductor manufacturing pollution control. Summary of the Invention

[0005] The main object of the present invention is to solve the deficiencies existing in the above-mentioned background technology and design a wet electronic chemical absorbing tube and a preparation method thereof. The characteristics of the present invention are to develop high-purity high-density polyethylene raw materials, optimize the production process and transform the materials of key components, and create a high-clean workshop to prepare a high-cleanliness absorbing tube that can meet the requirements of semiconductor use.

[0006] To achieve the above technical features, the object of the present invention is achieved as follows: A wet electronic chemical absorbing tube and a preparation method thereof, which comprise high-density polyethylene plastic particles as production raw materials, an injection molding production line, an extrusion production line, an ultrasonic cleaning machine and a dust-free production workshop; the high-density polyethylene (HDPE) raw materials are transported to the feed bins of the injection molding machine and the extrusion production line through a central feeding system; the injection molding production line extrudes the raw material particles into a mold through a screw under high-temperature melting conditions for integral injection molding; the extrusion production line uses an extruder to extrude the raw material particles into a hose, and the hose passes through a water tank under the action of a tractor for cooling and shaping, and finally the cooled and shaped tube is cut into a plastic tube of a fixed length by a cutting machine; the ultrasonic cleaning machine puts the processed injection molded parts and extruded plastic tubes into the cleaning machine for ultrasonic cleaning.

[0007] The injection molding production line comprises a feed bin and an injection molding machine; the injection molding machine melts the high-density polyethylene raw materials in the feed bin at high temperature and forms them integrally in the mold to obtain plastic parts.

[0008] The extrusion production line comprises an extruder, a cooling water tank, a tractor, a cutting machine and a finished product collection table; the extruder extrudes the raw materials at high temperature and melts them into a hose; the water tank is placed behind the extruder to cool and shape the hose; the tractor is placed behind the water tank to transport the extruded tube to the finished product collection table; the cutting machine cuts the extruded tube into a plastic tube of a fixed length.

[0009] The ultrasonic cleaning machine puts the processed injection molded parts and extruded tubes into ultrapure water for ultrasonic cleaning, dries them with high-purity nitrogen, and then packs and seals them.

[0010] The dust-free production workshop comprises a thousand-class dust-free room and a hundred-class dust-free room; among them, high-density polyethylene plastic particles, the injection molding production line and the extrusion production line are placed in the thousand-class dust-free room; the ultrasonic cleaning machine and the packing and sealing are placed in the hundred-class dust-free room.

[0011] The wet electronic chemical absorbing tube and the preparation method thereof comprise the following steps: Step S1: Store the production raw materials in a thousand-class dust-free environment. Use a central feeding system to transport high-density polyethylene (HDPE) plastic particles to the feed bins of the injection molding production line and the extrusion production line. When the material bin reaches the upper and lower limits of the continuous feeding amount, the feeding system automatically starts and stops to achieve automatic feeding of the system.

[0012] Step S2: The injection molding machine heats and melts the high-density polyethylene raw materials using the stepped temperature sections of the barrel. At the same time, the plasticizing pressure generated by the rotation of the screw continuously transports the raw materials into the mold cavity for injection molding. After the mold cools and solidifies for a certain period of time, the injection molded part of the suction tube can be obtained.

[0013] Step S3: The extruder heats and melts the high-density polyethylene raw materials using the stepped temperature sections of the barrel. At the same time, the plasticizing pressure generated by the rotation of the screw continuously transports the raw materials to the die head to form a plastic hose. Subsequently, under the action of the tractor, the hose cools and solidifies in the water tank. After setting the length of the extruded tube, the cutting machine cuts the shaped pipe into an extruded tube of a fixed length and places it on the finished product collection table.

[0014] Step S4: After Steps S2 and S3 are completed, put the plastic parts and the extruded tubes into ultrapure water for ultrasonic cleaning. After drying with high-purity nitrogen, assemble the plastic parts and the extruded tubes together and then package and plastic-seal them to complete the preparation of the high-purity suction tube for wet electronic chemicals.

[0015] The high-density polyethylene includes any one or a combination of multiple of Tosoh 8D01A and Dalin 5502; when using a combination of Tosoh 8D01A and Dalin 5502, the mass ratio of Tosoh 8D01A to Dalin 5502 is 7 - 8:2 - 3.

[0016] In Step S2, in a thousand-class dust-free environment, heat and melt the high-density polyethylene in the injection molding machine using the stepped temperature sections of the barrel. The set temperature of the first section of the barrel is 220 - 215 °C, the second section is 215 - 210 °C, the third section is 210 - 205 °C, and the fourth section is 205 - 200 °C.

[0017] In some preferred embodiments, in Step S2, in a thousand-class dust-free environment, heat and melt the high-density polyethylene in the injection molding machine using the stepped temperature sections of the barrel. The set temperature of the first section of the barrel is 215 °C, the second section is 210 °C, the third section is 205 °C, and the fourth section is 200 °C.

[0018] The plasticizing pressure generated by the rotation of the screw continuously transports the raw materials into the mold cavity for injection molding. The injection pressure is 110 - 120 Mpa, the speed is 20 - 25 cm / s, and after the mold cools and solidifies for 15 - 18 s, the injection molded part of the suction tube is obtained.

[0019] In step S3, under a thousand-class dust-free room environment, high-density polyethylene is heated and melted in an extruder using a barrel stepped temperature section. The temperature of the first barrel zone is 200 - 185 °C, the temperature of the second barrel zone is 200 - 185 °C, the temperature of the third barrel zone is 200 - 185 °C, the temperature of the fourth barrel zone is 200 - 185 °C. At the same time, the screw speed is set to 10 - 12 r / min, generating a plasticizing pressure to continuously convey the raw material to the die head to form a plastic hose. The flange temperature of the extruder is set to 200 - 185 °C, the head temperature is set to 200 - 190 °C, and the die temperature is set to 210 - 200 °C.

[0020] In some preferred embodiments, in step S3, under a thousand-class dust-free room environment, high-density polyethylene is heated and melted in an extruder using a barrel stepped temperature section. The temperature of the first barrel zone is 185 °C, the temperature of the second barrel zone is 185 °C, the temperature of the third barrel zone is 185 °C, the temperature of the fourth barrel zone is 185 °C. At the same time, the screw speed is set to 12 r / min, generating a plasticizing pressure to continuously convey the raw material to the die head to form a plastic hose. The flange temperature of the extruder is set to 185 °C, the head temperature is set to 190 °C, and the die temperature is set to 200 °C.

[0021] In step S3, under the action of a tractor at a speed of 2.0 - 2.2 cm / s, the plastic hose is cooled and shaped in ultrapure water, and the water temperature is 10 - 15 °C.

[0022] In steps S1 and S2, after high-strength nitriding treatment of the key component screw in the injection molding machine and the extruder, a Teflon powder is sprayed on the screw surface for fluoroplastic coating treatment to reduce the precipitation of metal impurities after the screw contacts the raw material.

[0023] The high-strength nitriding treatment process is to degrease and polish the screw made of alloy steel, and then introduce ammonia gas in a nitriding furnace at 500 - 550 °C for nitriding treatment.

[0024] The spraying of Teflon powder treatment is to heat and degrease the screw after high-strength nitriding treatment, and then blow the Teflon PTFE powder particles from the nozzle of the spray gun by compressed air and spray them onto the screw.

[0025] In steps S2 and S3, in the feed bin of the injection molding machine or in the feed bin of the extruder, the feed bin is designed with a raw material bag dust removal and metal detection device to remove the dust and impurities of the raw material.

[0026] In step S4, in a hundred-class dust-free room environment, the plastic parts and extrusion tubes produced in steps S2 and S3 are placed in ultrapure water with a resistivity of 18.2 MΩ for ultrasonic cleaning for 10 - 15 min. After purging with high-purity nitrogen, the plastic parts and extrusion tubes are assembled together and then packaged and sealed, thus completing the preparation of the extraction tube.

[0027] The present invention has the following beneficial effects: 1. Develop high-purity and high-density polyethylene (HDPE) production raw materials and use a central feeding system to transport them to the injection molding and extrusion production lines, and perform bag dust removal and metal impurity removal treatments, which improves the cleanliness of the production raw materials for the suction pipes.

[0028] 2. After performing high-strength nitriding treatment on the key component screw in the injection molding machine and the extruder, use the Teflon powder spraying process to coat the surface of the screw with fluoroplastics, which greatly reduces the precipitation of metal impurities after the screw contacts the raw materials and effectively improves the product cleanliness.

[0029] 3. By optimizing the process parameters in the production process, compared with the traditional constant temperature heating method, the heating temperature is gradually decreased from the raw material feeding section to the product forming section for forming, so that the raw materials are fully melted and heated evenly. At the same time, the reduction of the end temperature effectively reduces the carbonization and blackening of the raw materials caused by excessive temperature, and improves the cleanliness of the product.

[0030] 4. Optimize the production process links and production environment control of the suction pipes, and build Class 1000 and Class 100 clean rooms for production and ultrasonic cleaning and encapsulation use, which improves the cleanliness of the products and can meet the cleanliness requirements of the semiconductor industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will be further described below in conjunction with the drawings and embodiments.

[0032] Figure 1 A production flow chart of a wet electronic chemical suction pipe.

[0033] Figure 2 A layout diagram of a wet electronic chemical suction pipe production line.

[0034] In the figure: 1 - injection molding machine, 2 - bag dust removal and metal impurity removal device, 3 - injection molded part, 4 - extruder, 5 - cooling water tank, 6 - tractor, 7 - cutting machine, 8 - finished product collection table, 9 - extruded pipe; among them, the suction pipe is assembled by 3 and 9.

[0035] Figure 3 It is a three-dimensional structure diagram of the injection molded part, extruded pipe, and suction pipe. DETAILED DESCRIPTION OF THE INVENTION

[0036] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following describes in detail the specific implementation manners, structures, features, and effects of the present invention in conjunction with the embodiments. The raw material grades used in the following embodiments and comparative examples are as follows: High-density polyethylene A: Performance of Tosoh 8D01A. With a load of 2.16 kg, the melt index at 190 °C is 0.05; the density is 0.957 g / cm 3 ; the tensile yield strength is 29 Mpa; the elongation at break is 700%.

[0037] High-density polyethylene B: Performance of Dalin 5502. With a load of 2.16 kg, the melt index at 190 °C is 0.33; the density is 0.956 g / cm 3 ; the tensile yield strength is 31 Mpa; the elongation at break is 500%.

[0038] High-density polyethylene C: Performance of Formosa Plastics 7501. With a load of 2.16 kg, the melt index at 190 °C is 0.02; the density is 0.950 g / cm 3 ; the tensile yield strength is 10 Mpa; the elongation at break is 50%.

[0039] Example 1 A wet electronic chemical absorbing tube and its preparation method, including the following processes: Step S1: High-density polyethylene A is conveyed by a suction machine to the feed bin of an injection molding machine under the action of a central feeding system. When the material bin reaches the upper and lower limits of the continuous feeding amount, the central feeding system automatically starts and stops to achieve automatic feeding of the system. In a thousand-class dust-free room environment, the injection molding machine heats and melts high-density polyethylene A using a stepped temperature section of the barrel. The set temperature of the first section of the barrel is 215 °C, the second section is 210 °C, the third section is 205 °C, and the fourth section is 200 °C. At the same time, the plasticizing pressure generated by the rotation of the screw continuously conveys the raw material to the mold cavity for injection molding. After the injection pressure is 115 Mpa and the speed is 25 cm / s, and the mold is cooled and solidified for 18 s, the injection molded part of the absorbing tube can be obtained.

[0040] Step S2: High-density polyethylene A is conveyed by a suction machine to the feed bin of an extruder under the action of a central feeding system. When the material bin reaches the upper and lower limits of the continuous feeding amount, the central feeding system automatically starts and stops to achieve automatic feeding of the system. In a thousand-class dust-free room environment, the extruder heats and melts high-density polyethylene A using a stepped temperature section of the barrel. The temperature of the first zone of the barrel is 185 °C, the second zone is 180 °C, the third zone is 175 °C, and the fourth zone is 170 °C. At the same time, the screw speed is set to 15 r / min, and the plasticizing pressure is generated to continuously convey the raw material to the die head to form a plastic hose. The flange temperature is set to 170 °C, the head temperature is set to 175 °C, and the mold temperature is set to 185 °C. Subsequently, under the action of a traction machine at a speed of 2.5 cm / s, the hose is cooled and solidified in a water tank with a resistivity of 18.2 MΩ and a water temperature of 15 °C for ultrapure water. After setting the length of the extruded tube, the cutting machine cuts the shaped pipe into an extruded tube of a fixed length and places it on the finished product collection table.

[0041] Step S3: In a Class 100 cleanroom environment, assemble the plastic parts and the extrusion tube produced in Steps S1 and S2 together, and then pack and plastic-seal them to complete the preparation of the suction tube.

[0042] Example 2: A wet electronic chemical suction tube and its preparation method include the following processes: Step S1: High-density polyethylene A is transported by a suction machine to the feed bin of an injection molding machine under the action of a central feeding system. When the feed bin reaches the upper and lower limits of the replenishment amount, the central feeding system automatically starts and stops to achieve automatic feeding of the system. In a Class 1000 cleanroom environment, the injection molding machine heats and melts high-density polyethylene A using a stepped temperature section of the barrel. The set temperature of the first section of the barrel is 215°C, the second section is 210°C, the third section is 205°C, and the fourth section is 200°C. At the same time, the plasticizing pressure generated by the rotation of the screw continuously transports the raw materials to the mold cavity for injection molding. The injection pressure is 115 Mpa, and the speed is 25 cm / s. After the mold is cooled and solidified for 18 s, the injection molded part of the suction tube can be obtained.

[0043] Step S2: Use a mixer to mix high-density polyethylene A and high-density polyethylene B evenly in a ratio of 7:3, and then transport them to the feed bin of an extruder by a suction machine under the action of a central feeding system. When the feed bin reaches the upper and lower limits of the replenishment amount, the central feeding system automatically starts and stops to achieve automatic feeding of the system. In a Class 1000 cleanroom environment, the extruder heats and melts the mixture using a stepped temperature section of the barrel. The temperature of the first zone of the barrel is 190°C, the second zone is 185°C, the third zone is 180°C, and the fourth zone is 175°C. At the same time, the screw speed is set to 12 r / min, and the plasticizing pressure is generated to continuously transport the raw materials to the die head to form a plastic hose. The flange temperature is set to 180°C, the head temperature is set to 185°C, and the mold temperature is set to 195°C. Subsequently, under the action of a traction machine at a speed of 2.2 cm / s, the hose is cooled and solidified in a water tank with a resistivity of 18.2 MΩ and a water temperature of 15°C. After setting the length of the extrusion tube, the cutting machine cuts the shaped pipe into a fixed-length extrusion tube and places it on the finished product collection table.

[0044] Step S3: In a Class 100 cleanroom environment, assemble the plastic parts and the extrusion tube produced in Steps S1 and S2 together, and then pack and plastic-seal them to complete the preparation of the suction tube.

[0045] Example 3 A wet electronic chemical suction tube and its preparation method include the following processes: Step S1: High-density polyethylene A is conveyed by a suction machine to the feed bin of an injection molding machine under the action of a central feeding system. The feed bin is designed with a raw material bag dust collector and a metal detection device to remove dust and impurities from the raw materials. When the feed bin reaches the upper and lower limits of the continuous feeding amount, the central feeding system automatically starts and stops, realizing automatic feeding of the system. In a thousand-class clean room environment, the injection molding machine heats and melts high-density polyethylene A using a barrel stepped temperature section. The set temperature of the first section of the barrel is 215°C, the second section is 210°C, the third section is 205°C, and the fourth section is 200°C. The plasticizing pressure generated by the rotation of a specially treated fluorine-coated screw continuously conveys the raw materials into the mold cavity for injection molding. After the injection pressure is 115 Mpa and the speed is 25 cm / s, and the mold is cooled and solidified for 18 s, the injection molded part of the suction tube can be obtained.

[0046] Step S2: High-density polyethylene A and high-density polyethylene B are mixed evenly in a mixer at a ratio of 7:3, and are conveyed by a suction machine to the feed bin of an extruder under the action of a central feeding system. The feed bin is designed with a raw material bag dust collector and a metal detection device to remove dust and impurities from the raw materials. When the feed bin reaches the upper and lower limits of the continuous feeding amount, the central feeding system automatically starts and stops, realizing automatic feeding of the system. In a thousand-class clean room environment, the extruder heats and melts the mixture using a barrel stepped temperature section. The temperature of the first zone of the barrel is 190°C, the second zone is 185°C, the third zone is 180°C, and the fourth zone is 175°C. At the same time, the specially treated fluorine-coated screw rotates at a set speed of 12 r / min, generating plasticizing pressure to continuously convey the raw materials to the die head to form a plastic hose. The flange temperature is set at 180°C, the head temperature is set at 185°C, and the mold temperature is set at 195°C. Subsequently, the hose is cooled and solidified in a water tank with a resistivity of 18.2 MΩ and a water temperature of 15°C under the action of a tractor at a speed of 2.2 cm / s. After setting the length of the extruded tube, the cutting machine cuts the shaped pipe into an extruded tube of a fixed length and places it on the finished product collection table.

[0047] Among them, in S1 and S2, after the specially treated fluorine-coated screw is subjected to high-strength nitriding treatment, Teflon powder is sprayed on the screw surface for fluoroplastic coating treatment.

[0048] High-strength nitriding treatment process flow: The screw made of ordinary alloy steel is degreased by gas, and then polished and cleaned with alumina powder to remove oil stains and impurities on the surface. The treated screw is placed in a nitriding furnace, and the heating temperature is controlled within 500°C - 550°C. Subsequently, ammonia gas is introduced into the nitriding furnace. The active nitrogen atoms decomposed from ammonia gas in a high-temperature environment diffuse to the surface of the alloy steel to form a thin and hard iron nitride alloy compound layer, significantly improving the wear resistance, corrosion resistance, and high-temperature resistance of the screw surface.

[0049] Teflon PTFE powder high-temperature spraying process: The nitrided screw is then greased with an organic solvent and heated to approximately 400°C to completely evaporate. The workpiece is then mechanically cleaned and roughened using sandblasting to facilitate the bonding of the powder to the surface. Compressed air then blows Teflon PTFE powder particles from the spray gun nozzle, forming a uniform, cloud-like spray. The workpiece to be sprayed is grounded, creating an electrostatically charged area between the spray gun and the workpiece. The powder particles are attracted to the workpiece and adhere to it, forming a 0.1mm thick protective layer that significantly enhances the screw's non-stick properties, as well as its wear and corrosion resistance.

[0050] Step S3: In a Class 100 clean room environment, the plastic parts and extruded tubes produced in steps S1 and S2 are placed in ultrapure water with a resistivity of 18.2 MΩ and ultrasonically cleaned for 15 minutes. After purging with high-purity nitrogen, the plastic parts and extruded tubes are assembled together and packaged and sealed. This completes the preparation of the dip tube.

[0051] Comparative Example 1: A wet electronic chemical dip tube and a preparation method thereof, comprising the following processes: Step S1: High-density polyethylene (HDPE) C is conveyed by a suction machine into the feed bin of the injection molding machine under the action of the central feeding system. When the bin reaches the upper and lower limits of the feed volume, the central feeding system automatically starts and stops, realizing automatic feeding of the system. In a Class 1000 clean room environment, the injection molding machine heats and melts the HDPE C using the stepped temperature sections of the barrel. The barrel is set at 215°C for the first section, 215°C for the second section, 215°C for the third section, and 215°C for the fourth section. Simultaneously, the plasticizing pressure generated by the rotation of the screw continuously conveys the raw material into the mold cavity for injection molding. The injection pressure is 115 MPa and the speed is 25 cm / s. After the mold cools and sets for 23 seconds, the injection molded part of the dip tube is obtained.

[0052] Step S2: High-density polyethylene (HDPE) C is transported to the extruder feed bin by a suction machine under the action of the central feeding system. When the bin reaches the upper and lower limits of the feed amount, the central feeding system automatically starts and stops, realizing automatic feeding of the system. In a Class 1000 clean room environment, the extruder heats and melts the HDPE C using the stepped temperature section of the barrel. The temperature of barrel zone 1 is 190°C, the temperature of barrel zone 2 is 190°C, the temperature of barrel zone 3 is 190°C, and the temperature of barrel zone 4 is 190°C. At the same time, the screw speed is set to 15r / min, generating plasticizing pressure to continuously transport the raw material to the die head to form a plastic hose. The flange temperature is set to 190°C, the head temperature is set to 190°C, and the mold temperature is set to 190°C. The hose is then cooled and shaped in a water tank with an ultrapure water resistivity of 18.2MΩ and a water temperature of 15°C at a speed of 2.5cm / s. After the length of the extruded tube is set, the cutting machine cuts the shaped tube into extruded tubes of a fixed length and places them on the finished product collection table.

[0053] Step S3: In a Class 100 cleanroom environment, assemble the plastic parts and the extruded tube produced in Steps S1 and S2 together, and then pack and plastic-seal them to complete the preparation of the suction tube.

[0054] Comparative Example 2: A wet electronic chemical suction tube and its preparation method include the following processes: Step S1: High-density polyethylene C is conveyed by a suction machine to the feed bin of an injection molding machine under the action of a central feeding system. When the bin reaches the upper and lower limits of the continuous feeding amount, the central feeding system automatically starts and stops to achieve automatic feeding of the system. In a Class 1000 cleanroom environment, the injection molding machine heats and melts high-density polyethylene C using a barrel stepped temperature section. The set temperature of the first section of the barrel is 220°C, the second section is 220°C, the third section is 220°C, and the fourth section is 220°C. At the same time, the plasticizing pressure generated by the rotation of the screw continuously conveys the raw material to the mold cavity for injection molding. The injection pressure is 115 Mpa, the speed is 25 cm / s, and after the mold is cooled and solidified for 23 s, the injection molded part of the suction tube can be obtained.

[0055] Step S2: Use a mixer to mix high-density polyethylene C and high-density polyethylene A evenly in a ratio of 7:3, and convey them to the feed bin of an extruder by a suction machine under the action of a central feeding system. When the bin reaches the upper and lower limits of the continuous feeding amount, the central feeding system automatically starts and stops to achieve automatic feeding of the system. In a Class 1000 cleanroom environment, the extruder heats and melts high-density polyethylene C using a barrel stepped temperature section. The temperature of the first zone of the barrel is 185°C, the second zone is 185°C, the third zone is 185°C, and the fourth zone is 185°C. At the same time, the screw speed is set to 21 r / min, and the plasticizing pressure generated conveys the raw material continuously to the die head to form a plastic hose. The flange temperature is set to 190°C, the head temperature is set to 190°C, and the mold temperature is set to 190°C. Subsequently, under the action of a traction machine at a speed of 2.5 cm / s, the hose is cooled and solidified in a water tank with a resistivity of 18.2 MΩ and a water temperature of 15°C for ultrapure water. After setting the length of the extruded tube, the cutting machine cuts the shaped pipe into a fixed-length extruded tube and places it on the finished product collection table.

[0056] Step S3: In a Class 100 cleanroom environment, assemble the plastic parts and the extruded tube produced in Steps S1 and S2 together, and then pack and plastic-seal them to complete the preparation of the suction tube.

[0057] Comparative Example 3: A wet electronic chemical suction tube and its preparation method include the following processes: Step S1: High-density polyethylene C is conveyed by a suction machine to the feed bin of an injection molding machine under the action of a central feeding system. When the upper and lower limits of the continuous feeding amount of the bin are reached, the central feeding system automatically starts and stops, realizing automatic feeding of the system. In a thousand-class cleanroom environment, the injection molding machine heats and melts high-density polyethylene C using the stepped temperature section of the barrel. The set temperature of the first section of the barrel is 215°C, the second section is 210°C, the third section is 205°C, and the fourth section is 200°C. At the same time, the plasticizing pressure generated by the rotation of the screw continuously conveys the raw material to the mold cavity for injection molding. The injection pressure is 115 Mpa, and the speed is 25 cm / s. After the mold is cooled and solidified for 23 s, the injection molded part of the suction tube can be obtained.

[0058] Step S2: High-density polyethylene C is conveyed by a suction machine to the feed bin of an extruder under the action of a central feeding system. When the upper and lower limits of the continuous feeding amount of the bin are reached, the central feeding system automatically starts and stops, realizing automatic feeding of the system. In a thousand-class cleanroom environment, the extruder heats and melts high-density polyethylene C using the stepped temperature section of the barrel. The temperature of the first zone of the barrel is 185°C, the second zone is 180°C, the third zone is 175°C, and the fourth zone is 170°C. At the same time, the screw speed is set to 15 r / min, generating a plasticizing pressure to continuously convey the raw material to the die head to form a plastic hose. The flange temperature is set to 170°C, the head temperature is set to 175°C, and the mold temperature is set to 185°C. Subsequently, under the action of a traction machine at a speed of 2.5 cm / s, the hose is cooled and solidified in a water tank with an ultrapure water resistivity of 18.2 MΩ and a water temperature of 15°C. After setting the length of the extruded tube, the cutting machine cuts the shaped pipe into a fixed-length extruded tube and places it on the finished product collection table.

[0059] Step S3: In a hundred-class cleanroom environment, the plastic parts and extruded tubes produced in Steps S1 and S2 are assembled together and then packaged and heat-sealed, thus completing the preparation of the suction tube.

[0060] Formulate an experimental plan to conduct cleanliness detection on Examples 1, 2, 3 and Comparative Examples 1, 2, 3: Put the suction tubes composed of plastic parts and extruded tubes into PFA storage tanks 1-4 filled with electronic-grade sulfuric acid. Among them, storage tanks 1 and 2 are used for detecting the precipitation of metal ions, and storage tanks 3 and 4 are used for detecting the precipitation of particulate matter. Experimental conditions: Hundred-class cleanroom, temperature 85°C, standing for 7 days. The results of metal ion precipitation are shown in Table 1, and the results of particulate matter precipitation are shown in Table 2.

[0061] Table 1. Metal ion precipitation of the suction tubes prepared in each example and comparative example

[0062] Table 2. Particulate matter precipitation of the suction tubes prepared in each example and comparative example

[0063] Based on the data in the above table, we can draw the following conclusions: In Example 3, a high-purity, high-density polyethylene raw material formulation was developed, followed by bag dust removal and metal impurity removal. A specially treated fluorine-coated screw was used to heat and melt the raw material at a temperature gradient, and the dip tube was ultrasonically cleaned. The resulting dip tube maintained low metal and particulate precipitation in high-temperature, highly oxidizing wet electronic chemical testing, demonstrating that the process employed in this invention can produce high-purity dip tubes that meet semiconductor application requirements.

[0064] The above embodiments are merely preferred technical solutions of the present invention and should not be construed as limiting the present invention. The embodiments and features in the embodiments of this application may be arbitrarily combined with each other unless they conflict. The scope of protection of the present invention shall be the technical solutions described in the claims, including equivalent alternatives to the technical features of the technical solutions described in the claims. Equivalent alternatives and improvements within this scope are also within the scope of protection of the present invention.

Claims

1. A preparation method of a wet electronic chemical absorbent tube, characterized in that It includes the following steps: Step S1: Heat and melt the high-density polyethylene raw material in an injection molding machine using the barrel stepped temperature section, and then continuously transport the molten raw material to the mold cavity for injection molding under the plasticizing pressure generated by the rotation of the screw. After the mold is cooled and solidified, the injection-molded part of the suction tube is obtained. Step S2: Heat and melt the high-density polyethylene raw material in an extruder using the barrel stepped temperature section, and then continuously transport the molten raw material to the die head under the plasticizing pressure generated by the rotation of the screw to form a plastic hose. Subsequently, under the action of a tractor, the hose is cooled and cut and shaped in a water tank to obtain an extruded tube. Step S3: In a Class 100 cleanroom environment, assemble the plastic parts and the extruded tube produced in Steps S1 and S2 together and then package and plastic-seal them to complete the preparation of the suction tube.

2. The preparation method of a wet electronic chemical absorbent tube according to claim 1, characterized in that: The high-density polyethylene includes any one or a combination of multiple of Tosoh 8D01A and Dalin 5502; when using a combination of Tosoh 8D01A and Dalin 5502, the mass ratio of Tosoh 8D01A to Dalin 5502 is 7-8:2-3.

3. The preparation method of a wet electronic chemical absorbent tube according to claim 1, characterized in that: In Step S1, in a Class 1000 cleanroom environment, heat and melt the high-density polyethylene in an injection molding machine using the barrel stepped temperature section. The set temperature of the first section of the barrel is 220-215°C, the second section is 215-210°C, the third section is 210-205°C, and the fourth section is 205-200°C.

4. The preparation method of a wet electronic chemical absorbent tube according to claim 3, wherein: In Step S1, in a Class 1000 cleanroom environment, heat and melt the high-density polyethylene in an injection molding machine using the barrel stepped temperature section. The set temperature of the first section of the barrel is 215°C, the second section is 210°C, the third section is 205°C, and the fourth section is 200°C.

5. The preparation method of a wet electronic chemical absorbent tube according to claim 4, characterized in that: The plasticizing pressure generated by the rotation of the screw continuously transports the raw material to the mold cavity for injection molding. The injection pressure is 110-120 Mpa, the speed is 20-25 cm / s, and after the mold is cooled and solidified for 15-18 s, the injection-molded part of the suction tube is obtained.

6. The preparation method of a wet electronic chemical absorbing tube according to claim 1, characterized in that: In Step S2, in a Class 1000 cleanroom environment, heat and melt the high-density polyethylene in an extruder using the barrel stepped temperature section. The temperature of the first zone of the barrel is 200-185°C, the second zone is 200-185°C, the third zone is 200-185°C, the fourth zone is 200-185°C. At the same time, the screw speed is set to 10-12 r / min, and the plasticizing pressure is generated to continuously transport the raw material to the die head to form a plastic hose. The flange temperature of the extruder is set to 200-185°C, the head temperature is set to 200-190°C, and the mold temperature is set to 210-200°C.

7. The preparation method of a wet electronic chemical absorbing tube according to claim 1, characterized in that: In Step S2, in a Class 1000 cleanroom environment, heat and melt the high-density polyethylene in an extruder using the barrel stepped temperature section. The temperature of the first zone of the barrel is 185°C, the second zone is 185°C, the third zone is 185°C, the fourth zone is 185°C. At the same time, the screw speed is set to 12 r / min, and the plasticizing pressure is generated to continuously transport the raw material to the die head to form a plastic hose. The flange temperature of the extruder is set to 185°C, the head temperature is set to 190°C, and the mold temperature is set to 200°C. The plastic hose is cooled and shaped in ultrapure water under the action of a tractor at a speed of 2.0 - 2.2 cm / s, and the water temperature is 10 - 15 °C.

8. The preparation method of a wet electronic chemical absorbing tube according to claim 7, characterized in that: In steps S1 and S2, after high-strength nitriding treatment of the key component screw in the injection molding machine and the extruder, a Teflon powder is sprayed on the screw surface for fluoroplastics coating treatment to reduce the precipitation of metal impurities after the screw contacts the raw material.

9. The preparation method of a wet electronic chemical absorbing tube according to claim 1, characterized in that: In steps S1 and S2, in the feed bin of the injection molding machine or in the feed bin of the extruder, a dust removal device and a metal detection device for raw material cloth bags are designed in the feed bin to remove the dust and impurities of the raw material.

10. The preparation method of a wet electronic chemical absorbent tube according to claim 1, characterized in that: In a Class 100 cleanroom environment, the plastic parts and the extruded pipes produced in steps S1 and S2 are placed in ultrapure water with a resistivity of 18.2 MΩ for ultrasonic cleaning for 10 - 15 minutes. After purging with high-purity nitrogen, the plastic parts and the extruded pipes are assembled together and then packaged and sealed, thus completing the preparation of the extraction tube.

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