Manufacturing method of cutting adhesive tape base material
Through specific formulation and process design, a high-performance cutting tape substrate was prepared, which solved the problems of film expansion performance and adhesion of polyolefin substrates in wafer cutting, and realized an environmentally friendly and efficient wafer cutting process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- AIMI NEW MATERIALS (DONGGUAN) CO LTD
- Filing Date
- 2026-02-04
- Publication Date
- 2026-05-08
AI Technical Summary
Existing polyolefin substrates suffer from problems such as poor film expansion performance, appearance defects, weak adhesion between the substrate and the adhesive layer, and easy residue during wafer dicing, resulting in low production yield and efficiency, as well as insufficient environmental protection.
Using a specific formulation of metallocene linear low-density polyethylene, polymethyl methacrylate, ethylene propylene rubber grafted with maleic anhydride and antioxidants, combined with a high aspect ratio single screw extruder and dust-free environment treatment, a high-performance cutting tape substrate is manufactured by casting molding to form an outer and inner composite structure, and then embossed and corona treated.
A cutting tape substrate with excellent tensile properties, low stress relaxation, and low risk of residual adhesive was prepared. Its performance is superior to imported products, meets the requirements of high-end wafer cutting processes, and reduces environmental pollution.
Smart Images
Figure CN121991385A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor packaging materials technology, and more specifically to a method for manufacturing a cutting tape substrate. Background Technology
[0002] Wafer dicing tape is a key auxiliary material in semiconductor packaging processes, and the performance of its substrate directly affects the dicing quality of the wafer and the subsequent die pick-up efficiency. Currently, wafer dicing tape substrates on the market are mainly divided into two categories: one is made from polyvinyl chloride (PVC) through a calendering process; the other is made from polyolefins (such as polyethylene and polypropylene) through a casting process.
[0003] PVC substrates hold a major market share due to their superior overall performance, but they release harmful substances during production and waste disposal, posing serious environmental pollution problems and contradicting the trend of green manufacturing. Therefore, the industry is committed to developing environmentally friendly polyolefin substrates as alternatives. However, existing polyolefin substrates still face many technical bottlenecks in practical applications: First, domestically produced PVC substrates are prone to small molecule precipitation due to various additives in their formulations, leading to residual adhesive during wafer dicing and contaminating the wafer. Second, single-polyolefin substrates prepared using traditional casting methods suffer from poor film expansion performance (difficult to expand or prone to collapse due to stress relaxation after expansion) and surface defects caused by crystal points or poor plasticization. These defects can form bubbles or pits during subsequent adhesive coating, resulting in poor bonding between the adhesive layer and the substrate, ultimately leading to delamination, residual adhesive, or grain detachment during grain picking, severely impacting production yield and efficiency. Furthermore, the surface energy of single-polyolefin materials typically results in weak adhesion to the adhesive layer, further exacerbating the risk of residual adhesive. Currently, the substrate for high-performance cutting tape is almost entirely dependent on imports. Therefore, it is of great significance to develop a domestically produced method for manufacturing high-performance, low-pollution, and stable cutting tape substrates. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for manufacturing a cutting tape substrate. This method aims to solve problems such as easy collapse after film expansion of existing polyolefin substrates, poor coating due to numerous crystalline spots, and weak adhesion between the substrate and the adhesive layer leading to residue, through specific raw material formulation design, optimized production processes, and strict cleanliness control. This results in the manufacture of a high-performance cutting tape substrate with excellent tensile properties, low stress relaxation, high surface cleanliness, and no risk of residue.
[0005] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a method for manufacturing a cutting tape substrate, comprising the following steps: (1) Raw material preparation: Metallocene linear low-density polyethylene, polymethyl methacrylate, ethylene propylene rubber grafted with maleic anhydride and antioxidant are mixed according to the mass percentage to obtain a mixture. (2) Pretreatment: The mixture is subjected to dust removal treatment in a dust-free environment; (3) Melt extrusion: The pretreated mixture is fed into a single screw extruder for melt plasticization. The length-to-diameter ratio of the extruder screw is greater than the standard value, and the temperatures of zones 1-3 are set to 195℃, 210℃, and 220℃ respectively, while the temperatures of the remaining zones and the die head are set to 240℃. (4) Casting: The molten and plasticized material is extruded through a coat hanger-type co-extrusion die and cast onto a cooling roller for cooling and shaping; (5) Post-processing: The shaped film is embossed and corona treated in sequence, and then wound up to obtain the cutting tape substrate.
[0006] Further, the mass percentage composition of the mixture in step (1) is as follows: metallocene linear low-density polyethylene: 60-90%, polymethyl methacrylate: 10-40%, ethylene propylene rubber grafted with maleic anhydride: 5-8%, antioxidant: 1-3%.
[0007] Furthermore, the metallocene linear low-density polyethylene has a mass percentage of 65%.
[0008] Furthermore, the polymethyl methacrylate has a mass percentage of 25%.
[0009] Furthermore, the clean environment described in step (2) is a Class 10,000 cleanroom, and the dust removal process includes vacuuming the mixture into a cyclone separator above the extruder hopper for dust removal.
[0010] Furthermore, the single-screw extruder mentioned in step (3) is an extruder with a large length-to-diameter ratio.
[0011] Furthermore, in step (4), a double-layer co-extrusion die is used for extrusion to form a substrate structure with an outer layer and an inner layer.
[0012] Furthermore, the thickness ratio of the outer layer to the inner layer is 50-60 micrometers: 20-30 micrometers.
[0013] Furthermore, the raw material composition of both the outer and inner layers includes metallocene linear low-density polyethylene, polymethyl methacrylate, ethylene propylene rubber grafted with maleic anhydride, and antioxidants.
[0014] Furthermore, the inner layer material also includes low-density polyethylene (LDPE), and the mass percentage of low-density polyethylene in the inner layer material is 60-95%.
[0015] Compared with existing technologies, the technical solution of this patent achieves the following beneficial effects: 1. Metallocene linear low-density polyethylene (mLLDPE) is used as the main material, with a narrow molecular weight distribution, giving the substrate excellent tensile strength and toughness. The addition of polymethyl methacrylate (PMMA) improves the material's rigidity and surface hardness, enhancing its resistance to collapse after film expansion. Ethylene-propylene rubber grafted with maleic anhydride (EPDM-g-MAH) acts as a compatibilizer and toughening agent, not only improving the material's flexibility and impact resistance, but also enhancing the chemical bonding with the adhesive through its maleic anhydride functional groups, fundamentally reducing the risk of adhesive residue. The synergistic effect of these three components results in a substrate with high strength, good film expansion properties, and dimensional stability.
[0016] 2. Pre-treatment with a Class 10,000 cleanroom for batching and vacuum cyclone dust removal significantly reduces dust contamination in the raw materials, minimizing appearance defects caused by impurities at the source. The use of a high aspect ratio single-screw extruder, coupled with optimized segmented temperature processes, ensures that the material is fully sheared, mixed, and plasticized in the screw, eliminating poorly plasticized points and large crystals (particle size > 0.05mm). This results in a uniform, defect-free melt, avoiding problems such as bubbles during coating.
[0017] 3. This invention uses polyolefin materials entirely, avoiding the environmental pollution problems of PVC. At the same time, through the above-mentioned technical means, the resulting substrate achieves or even surpasses imported competitors in key properties such as tensile strength, elongation at break, and stress relaxation rate. In particular, it performs excellently in suppressing grain fly, meeting the requirements of high-end wafer cutting processes. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the processing technology of the present invention. Detailed Implementation
[0019] Please see Figure 1 As shown, the present invention provides a technical solution, a method for manufacturing a cutting tape substrate, comprising the following steps: (1) Raw material preparation: Metallocene linear low-density polyethylene, polymethyl methacrylate, ethylene propylene rubber grafted with maleic anhydride and antioxidant are mixed according to the mass percentage to obtain a mixture. (2) Pretreatment: The mixture is subjected to dust removal treatment in a dust-free environment; (3) Melt extrusion: The pretreated mixture is fed into a single screw extruder for melt plasticization. The length-to-diameter ratio of the extruder screw is greater than the standard value, and the temperatures of zones 1-3 are set to 195℃, 210℃, and 220℃ respectively, while the temperatures of the remaining zones and the die head are set to 240℃. (4) Casting: The molten and plasticized material is extruded through a coat hanger-type co-extrusion die and cast onto a cooling roller for cooling and shaping; (5) Post-processing: The shaped film is embossed and corona treated in sequence, and then wound up to obtain the cutting tape substrate.
[0020] Further, the mass percentage composition of the mixture in step (1) is as follows: metallocene linear low-density polyethylene: 60-90%, polymethyl methacrylate: 10-40%, ethylene propylene rubber grafted with maleic anhydride: 5-8%, and antioxidant: 1-3%. Preferably, the mass percentage of metallocene linear low-density polyethylene is 65%, and the mass percentage of polymethyl methacrylate is 25%.
[0021] Furthermore, when using a double-layer co-extrusion structure in step (4), the thickness ratio of the outer layer to the inner layer is controlled at (50-60) micrometers: (20-30) micrometers. Both the outer and inner layers can contain metallocene linear low-density polyethylene, polymethyl methacrylate, ethylene propylene rubber grafted with maleic anhydride, and antioxidants. Furthermore, the inner layer material can also contain low-density polyethylene, and the mass percentage of low-density polyethylene in the inner layer material is 60-95%.
[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.
[0023] Example 1: This example provides a method for manufacturing a double-layer co-extruded cutting tape substrate: Outer layer materials: ExxonMobil metallocene linear low-density polyethylene 3518CB, 65% by weight; Kuraray polymethyl methacrylate SA-FW001, 25% by weight; ethylene propylene rubber grafted with maleic anhydride, 3% by weight; other process aids, 5% by weight; BASF B216 antioxidant, 2% by weight.
[0024] Inner layer materials: Dow low-density polyethylene 505I, 65% by weight; Kuraray polymethyl methacrylate SA-FW001, 25% by weight; ethylene propylene rubber grafted with maleic anhydride, 3% by weight; other process aids, 5% by weight; BASF B216 antioxidant, 2% by weight.
[0025] The materials were prepared separately in a Class 10,000 cleanroom and then conveyed via vacuum to a cyclone separator above the extruder hopper for dust removal. Production was carried out using a Guangdong Shicheng SC / CPO-Ф95-1600 casting machine, with the extruder being a custom-designed single-screw extruder with a large length-to-diameter ratio to ensure uniform plasticization and the absence of crystal points. The screw zone temperatures were set to 195℃, 210℃, and 220℃, respectively, while the die and other zone temperatures were set to 240℃. The die was equipped with an American EDIER die, a coat hanger-type co-extrusion die. The melt was extruded through the die and cast onto cooling rollers for shaping, controlling the outer layer thickness to 55 microns and the inner layer thickness to 25 microns. The film was then traction, embossed with steel rollers, corona treated, and then wound up.
[0026] Example 2 differs from Example 1 in that the inner layer formula, outer layer formula, and all production process parameters are exactly the same as in Example 1.
[0027] Outer layer materials: ExxonMobil metallocene linear low-density polyethylene 3518CB, 65% by weight; Kuraray polymethyl methacrylate SA-FW001, 25% by weight; ethylene propylene rubber grafted with maleic anhydride, 3% by weight; other process aids, 5% by weight; BASF B216 antioxidant, 2% by weight.
[0028] Inner layer material: Dow low-density polyethylene 505I, 93% by weight; other process aids, 5% by weight; BASF B216 antioxidant, 2% by weight.
[0029] The materials were prepared separately in a Class 10,000 cleanroom and then conveyed via vacuum to a cyclone separator above the extruder hopper for dust removal. Production was carried out using a Guangdong Shicheng SC / CPO-Ф95-1600 casting machine, with the extruder being a custom-designed single-screw extruder with a large length-to-diameter ratio to ensure uniform plasticization and the absence of crystal points. The screw zone temperatures were set to 195℃, 210℃, and 220℃, respectively, while the die and other zone temperatures were set to 240℃. The die was equipped with an American EDIER die, a coat hanger-type co-extrusion die. The melt was extruded through the die and cast onto cooling rollers for shaping, controlling the outer layer thickness to 55 microns and the inner layer thickness to 25 microns. The film was then traction, embossed with steel rollers, corona treated, and then wound up.
[0030] Comparative Example 1 uses commercially available imported polyvinyl chloride (PVC) cutting tape as its substrate. Comparative Example 2 uses commercially available imported polyolefin cutting tape as its substrate.
[0031] Performance Testing and Results: Performance tests were conducted on the substrates prepared or obtained in Examples 1, 2, Comparative Example 1, and 2. The results are shown in the table below:
[0032] Test Method Description: Stress Relaxation Test (Amy Internal Test Method): After stretching the substrate to 100% of its elongation, record the stress value as A. After maintaining the 100% elongation for ten minutes, the stress value displayed is B. The stress relaxation test value is C = (AB) / A*100%. Tensile Strength: Refer to ASTM D638. Elongation at Break: Refer to ASTM D638. Grain Fly Percentage: Count the percentage of 1000 grains accidentally detached from the handling tray during the wafer dicing pick-up process.
[0033] As shown in the table above, although the substrates prepared in Examples 1 and 2 of this invention have slightly lower absolute tensile strength than the comparative examples (but are still at an excellent level), their performance in the machine direction (MD) and transverse direction (TD) is more balanced. The key stress relaxation rate C value is significantly higher than that of the two comparative examples, indicating that the substrate of this invention has stronger resistance to stress relaxation after film expansion, i.e., it is less prone to collapse after film expansion, which is crucial for maintaining stable grain positions. The grain fly rate, the most direct indicator of application effect, is much lower in the examples of this invention (especially Example 1) than in the two imported competing products, proving that it can effectively solve the problem of breakage during the picking process. In summary, the method of this invention successfully manufactures a high-performance, low fly rate environmentally friendly cutting tape substrate.
[0034] Example 3: This example is basically the same as Example 1, except that a controlled decomposition type multifunctional crosslinking agent is introduced into the outer layer formulation.
[0035] Outer layer materials: ExxonMobil metallocene linear low-density polyethylene 3518CB, 65% by weight; Kuraray polymethyl methacrylate SA-FW001, 25% by weight; ethylene propylene rubber grafted with maleic anhydride, 3% by weight; process aids, 5% by weight; BASF B216 antioxidant, 2% by weight; controlled decomposition multifunctional crosslinking agent (e.g., a compound of dicumyl peroxide and γ-(methacryloyloxy)propyltrimethoxysilane), 0.5% by weight.
[0036] Inner layer materials: Dow low-density polyethylene 505I, 65% by weight; Kuraray polymethyl methacrylate SA-FW001, 25% by weight; ethylene propylene rubber grafted with maleic anhydride, 3% by weight; other process aids, 5% by weight; BASF B216 antioxidant, 2% by weight.
[0037] The above materials are prepared in a Class 10,000 cleanroom and then conveyed via vacuum to a cyclone separator above the extruder hopper for dust removal. Production is carried out using a custom-designed single-screw extruder with a large length-to-diameter ratio and a coat hanger-type die. By precisely setting the temperature and speed of each section of the screw, the melt undergoes a specific shear-thermal history at the end of the extruder and in the die flow channel to activate the gradient reaction of the crosslinking agent. The screw zone temperatures are set to 195℃, 210℃, and 220℃, while the die and other zone temperatures are set to 240℃. The melt is extruded through the die and cast to a cooling roller for forming, controlling the outer layer thickness to be 55 micrometers and the inner layer thickness to be 25 micrometers. The film is then wound up after traction, steel roller embossing, corona treatment, and finally, winding.
[0038] In the existing formulation system, a controlled-decomposition multifunctional crosslinking agent (e.g., a compound containing peroxy ester bonds and siloxane bifunctional groups) is introduced. During melt extrusion, by precisely controlling the temperature and shear history, this crosslinking agent selectively undergoes non-uniform decomposition and reaction in the thickness direction of the substrate. Outer layer (close to the adhesive side): Under relatively high shear and temperature, the peroxy ester bonds of the crosslinking agent preferentially decompose, initiating mild chemical crosslinking between metallocene polyethylene and PMMA, forming a dense network. This significantly improves surface hardness, modulus, and heat resistance (reducing thermal relaxation during film expansion), while its siloxane groups migrate to the surface, further enhancing the chemical bonding with subsequent adhesives. Inner layer (away from the adhesive side): Under relatively mild processing conditions, the crosslinking agent mainly functions as a siloxane coupling agent, improving the compatibility of ethylene propylene rubber and the polyolefin matrix, forming a strong and tough physical entanglement network, maintaining high elasticity and elongation at break.
[0039] In this way, a gradient cross-linked structure with a rigid outer layer and a flexible inner layer is constructed within the same substrate without adding additional production steps. This gives the substrate surface high creep resistance, effectively resisting the shrinkage and collapse force after film expansion; while the inner layer maintains high elasticity, providing excellent tensile strength and flexibility for the whole, achieving a balance between easy film expansion and strong shape retention. In the single continuous process of cast extrusion, the microstructure can be actively controlled in the spatial direction through the precise design of a smart additive and process parameters.
[0040] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for manufacturing a cutting tape substrate, characterized in that, Includes the following steps: (1) Raw material preparation: Metallocene linear low-density polyethylene, polymethyl methacrylate, ethylene propylene rubber grafted with maleic anhydride and antioxidant are mixed according to the mass percentage to obtain a mixture. (2) Pretreatment: The mixture is subjected to dust removal treatment in a dust-free environment; (3) Melt extrusion: The pretreated mixture is fed into a single screw extruder for melt plasticization. The length-to-diameter ratio of the extruder screw is greater than the standard value, and the temperatures of zones 1-3 are set to 195℃, 210℃, and 220℃ respectively, while the temperatures of the remaining zones and the die head are set to 240℃. (4) Casting: The molten and plasticized material is extruded through a coat hanger-type co-extrusion die and cast onto a cooling roller for cooling and shaping; (5) Post-processing: The shaped film is embossed and corona treated in sequence, and then wound up to obtain the cutting tape substrate.
2. The method for manufacturing the cutting tape substrate according to claim 1, characterized in that, The mass percentage composition of the mixture in step (1) is as follows: metallocene linear low-density polyethylene: 60-90%, polymethyl methacrylate: 10-40%, ethylene propylene rubber grafted with maleic anhydride: 5-8%, antioxidant: 1-3%.
3. The method for manufacturing the cutting tape substrate according to claim 2, characterized in that, The metallocene linear low-density polyethylene has a mass percentage of 65%.
4. The method for manufacturing the cutting tape substrate according to claim 2, characterized in that, The polymethyl methacrylate has a mass percentage of 25%.
5. The method for manufacturing the cutting tape substrate according to claim 1, characterized in that, The clean environment mentioned in step (2) is a Class 10,000 cleanroom, and the dust removal process includes vacuuming the mixture into a cyclone separator above the extruder hopper for dust removal.
6. The method for manufacturing the cutting tape substrate according to claim 1, characterized in that, The single-screw extruder mentioned in step (3) is an extruder with a large length-to-diameter ratio.
7. The method for manufacturing the cutting tape substrate according to claim 1, characterized in that, In step (4), a double-layer co-extrusion die is used for extrusion to form a substrate structure with an outer layer and an inner layer.
8. The method for manufacturing the cutting tape substrate according to claim 7, characterized in that, The thickness ratio of the outer layer to the inner layer is 50-60 micrometers: 20-30 micrometers.
9. The method for manufacturing the cutting tape substrate according to claim 7, characterized in that, The outer and inner layers are composed of metallocene linear low-density polyethylene, polymethyl methacrylate, ethylene propylene rubber grafted with maleic anhydride, and antioxidants.
10. The method for manufacturing the cutting tape substrate according to claim 9, characterized in that, The inner layer material also includes low-density polyethylene (LDPE), and the mass percentage of low-density polyethylene in the inner layer material is 60-95%.