Wafer protection adhesive tape

Abstract

The application provides a wafer protection adhesive tape, which comprises a release layer, a barrier layer, a substrate layer and an adhesive layer arranged in sequence, and the release layer and the substrate layer are directly compounded through the barrier layer; the release layer comprises a silicone release agent, the substrate layer comprises a thermoplastic polyurethane elastomer rubber, and the barrier layer comprises EVA-g-MAH and POE-g-MAH; EVA-g-MAH:POE-g-MAH=2-5:1. The release force provided by the non-silicone release agent is large, which leads to large friction in the use process, causes the film to be deformed, and makes the film not flat and air bubbles to be easily generated when the film is pasted, thereby reducing the yield. Therefore, the application uses EVA-g-MAH and POE-g-MAH as the barrier layer to solve the poisoning reaction between TPU and the silicone release agent, and uses POE-g-MAH to comprehensively improve the rebound performance of TPU, so that the preparation efficiency of the wafer protection adhesive tape can be improved.

Description

Technical Field

[0001] This invention belongs to the field of wafer cutting technology, and particularly relates to a wafer protective tape. Background Technology

[0002] Wafer dicing is an essential step in the semiconductor chip manufacturing process. It's a post-chip slicing process where a pre-cut wafer is divided into individual chips according to their size. Since most semiconductor chips are made of silicon, a brittle material, chipping at the edges can affect chip strength and damage the surface finish during dicing. This can contaminate subsequent processes. To avoid these problems, a protective tape is applied during wafer dicing to provide protection and prevent future issues.

[0003] Currently available protective tapes for wafer dicing consist of a release layer, a substrate layer, and an adhesive layer. The release layer is generally made of silicone. To give the protective tape resilience and flexibility, the substrate layer is generally made of polyvinyl chloride (PVC) or polyolefin (PO). However, PVC plasticizers are prone to leaching and residue, and are also carcinogenic, toxic to human health and the environment. PO, on the other hand, has a high shrinkage rate and poor dimensional stability, making it difficult to produce high-precision products, resulting in a low wafer yield.

[0004] Thermoplastic polyurethane elastomer (TPU) not only possesses most of the properties of rubber and ordinary plastics, but also boasts excellent comprehensive physical and chemical properties. It combines the softness of rubber with the hardness of rigid plastics, making it a novel, environmentally friendly polymer material that falls between rubber and plastics. Therefore, TPU holds promise as a replacement for commonly used PVC and PO materials in this field.

[0005] Secondly, during wafer dicing, film spreading, and film lamination processes, the back of the film generates frictional resistance with the equipment. Release layers help reduce friction and facilitate chip transfer and handling. Most importantly, the film lamination process uses rollers; high frictional resistance hinders film flatness and can even stretch and deform the film, resulting in poor chip bonding and severely impacting wafer processing yield. Non-silicone release agents provide high release force, leading to significant friction during unwinding and lamination of the wafer protective film, causing deformation and resulting in uneven application, air bubbles, and further reducing yield. Silicone release agents, on the other hand, offer excellent release performance, mitigating these problems and are widely used in the tape and release film industries.

[0006] However, in practical applications, combining TPU and silicone release agents simultaneously in wafer dicing processes remains a significant challenge. This is primarily due to the poisoning reaction between TPU and the platinum catalyst in the silicone release agent. When the silicone release agent is applied to the TPU, the poisoning reaction prevents the silicone from curing, resulting in poor release properties on the TPU film and hindering the successful production of protective tapes for wafer dicing. Therefore, providing a wafer protective tape that can simultaneously utilize a TPU substrate layer and a silicone release agent is an urgent problem to be solved. Summary of the Invention

[0007] The purpose of this invention is to provide a wafer protective tape that can effectively reduce environmental pollution and improve the problem of simultaneous application of TPU and silicone release agent.

[0008] According to one aspect of the present invention, a wafer protective tape is provided, the wafer protective tape comprising a release layer, a barrier layer, a substrate layer, and an adhesive layer disposed sequentially, wherein the release layer and the substrate layer are directly laminated through the barrier layer; the release layer comprises an organosilicon release agent, the substrate layer comprises thermoplastic polyurethane elastomer rubber (TPU), and the barrier layer comprises maleic anhydride modified EVA plastic (EVA-g-MAH) and maleic anhydride modified POE plastic (POE-g-MAH); wherein the ratio of maleic anhydride modified EVA plastic to maleic anhydride modified POE plastic is 2 to 5:1.

[0009] To prevent poisoning reactions between the substrate layer and the release layer, the wafer protective tape provided by this invention incorporates a barrier layer between them to prevent direct contact and potential poisoning. Furthermore, the inventors discovered in practical applications that the high elasticity of TPU leads to rapid rebound during the film expansion process, resulting in rapid film shrinkage and potential chip detachment, which negatively impacts wafer yield. This invention addresses this issue by combining maleic anhydride-modified EVA plastic (EVA-g-MAH) and maleic anhydride-modified POE plastic (POE-g-MAH). While maintaining the flexibility and ductility of the wafer protective tape, these two materials serve as a barrier layer, effectively resolving the poisoning reaction between TPU and the silicone release agent. Moreover, by combining a specific ratio of EVA-g-MAH and POE-g-MAH, the resilience of TPU is enhanced, strengthening the bond between the barrier layer and the substrate layer, thereby improving wafer yield. Furthermore, by utilizing the good compatibility between EVA-g-MAH and POE-g-MAH and TPU, and the fact that all three have similar processing temperatures, the preparation efficiency of the wafer protective tape can be further improved. Therefore, the wafer protective tape provided by this invention is environmentally friendly and can also improve wafer yield. The maleic anhydride-modified POE plastic selected in this invention can be a polymer of ethylene and butene, or a polymer of ethylene and octene.

[0010] Preferably, in the barrier layer, the maleic anhydride-modified EVA plastic has a maleic anhydride group grafting rate of ≥5%; and / or, the maleic anhydride-modified POE plastic has a maleic anhydride group grafting rate of ≥8%.

[0011] Preferably, the adhesive layer comprises hydrogenated styrene-butadiene block copolymer (SEBS) and maleic anhydride-modified C5 petroleum resin (C5-MAH). In the adhesive layer, by combining SEBS and maleic anhydride-modified C5 resin, SEBS provides cohesive strength, while the maleic anhydride-modified C5 resin provides tackiness; their synergistic effect provides excellent adhesion to the adhesive layer. Furthermore, it increases the resistance of the adhesive layer to the cutting fluid during wafer dicing, thereby improving processing efficiency.

[0012] Preferably, in the adhesive layer, the mass ratio of hydrogenated styrene-butadiene block copolymer to maleic anhydride-modified C5 petroleum resin is 3 to 7:1.

[0013] Preferably, the hydrogenated styrene-butadiene block copolymer is prepared by polystyrene and polybutadiene, and the molar ratio of polystyrene to polybutadiene is (25-35):(65-75).

[0014] Preferably, the molecular weight of the maleic anhydride-modified C5 petroleum resin is 400-1000.

[0015] Preferably, the wafer protective tape further includes a reinforcing layer; the reinforcing layer is disposed between the substrate layer and the adhesive layer; the reinforcing layer comprises maleic anhydride-modified EVA plastic. The reinforcing layer can further improve the bonding force between the adhesive layer and the substrate layer, preventing delamination and detachment of the wafer protective tape during wafer dicing. Furthermore, the maleic anhydride-modified EVA plastic used in the reinforcing layer has good compatibility with the adhesive layer and the substrate layer, ensuring processing efficiency.

[0016] Preferably, in the reinforcing layer, the maleic anhydride grafting rate of the maleic anhydride-modified EVA plastic is 10-12%. Compared to the isolation layer, the maleic anhydride-modified EVA plastic used in the reinforcing layer has a higher maleic anhydride grafting rate and greater EVA polarity, thereby increasing the bonding force between the base film and the adhesive layer. This prevents delamination during wafer dicing and film expansion due to cutting by the dicing blade or film stretching.

[0017] Preferably, the thickness ratio is calculated as follows: release layer: barrier layer: substrate layer: adhesive layer = (0.05~0.5): (5~8): (55~80): (6~12).

[0018] Preferably, the thickness of the barrier layer is 5–8 μm.

[0019] Preferably, the thickness of the reinforcing layer is 4–8 μm.

[0020] Preferably, the thickness of the wafer protective tape is 60–108 μm.

[0021] Preferably, the wafer protective tape is prepared by an extrusion casting process. Attached Figure Description

[0022] Figure 1 This is a cross-sectional view of the wafer protective tape prepared in Example 1;

[0023] Figure 2 The appearance of the wafer protective tape prepared in Example 1;

[0024] Figure 3 The appearance of the wafer protective tape prepared in Comparative Example 1;

[0025] Figure 4 The wafer protective tape prepared in Example 1 is used to describe the appearance of the wafer and the slit marks on the film surface after the wafer is cut by the dicing knife;

[0026] Figure 5 The wafer protective tape prepared in Example 6 is used to show the appearance of the wafer and the cut marks on the film surface after the wafer is cut by the dicing knife. Detailed Implementation

[0027] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below with reference to the embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0028] Example 1

[0029] 1. Raw materials used in the preparation of wafer protective tape

[0030] The raw materials and layer thicknesses used in preparing the wafer protective tape in this embodiment are shown in Table 1. Specifically, based on the mass ratio, the ratio of EVA-g-MAH to POE-g-MAH in the barrier layer is 3:1; and the ratio of SEBS to C5-MAH in the adhesive layer is 5:1. Furthermore, in this embodiment, the EVA-g-MAH used is DuPont Bynel 3000 or Arkema OREVAC 18211; and the POE-g-MAH used is Dow GR 216.

[0031] Table 1. Raw materials used in each layer of the wafer protective tape provided in this embodiment.

[0032]

[0033] 2. Method for preparing wafer protective tape

[0034] A four-layer extrusion casting process is used to simultaneously fabricate a barrier layer, a substrate layer, a reinforcing layer, and an adhesive layer. The processing temperature is 180–210°C. Subsequently, an organosilicon release agent is applied to the surface of the barrier layer (the side away from the substrate layer). A cross-sectional view of the wafer protective tape produced in this embodiment is shown below. Figure 1 As shown.

[0035] Example 2

[0036] This embodiment prepares wafer protective tape with reference to the formula and method provided in Example 1. The difference from Example 1 is that in this embodiment, when preparing wafer protective tape, the mass ratio of EVA-g-MAH:POE-g-MAH in the barrier layer is calculated to be 2:1. Apart from the above differences, the operation steps for preparing wafer protective tape in this embodiment are strictly consistent with those in Example 1.

[0037] Example 3

[0038] This embodiment prepares wafer protective tape with reference to the formula and method provided in Example 1. The difference from Example 1 is that in this embodiment, when preparing wafer protective tape, the mass ratio of EVA-g-MAH:POE-g-MAH in the barrier layer is calculated to be 5:1. Apart from the above differences, the operation steps for preparing wafer protective tape in this embodiment are strictly consistent with those in Example 1.

[0039] Example 4

[0040] This embodiment refers to the formulation and method provided in Example 1 to prepare wafer protective tape. The difference from Example 1 is that in this embodiment, the grafting rate of maleic anhydride groups of EVA-g-MAH in the barrier layer is 10% when preparing the wafer protective tape. Apart from the above differences, the operation steps for preparing the wafer protective tape in this embodiment are strictly consistent with those in Example 1.

[0041] Example 5

[0042] This embodiment refers to the formulation and method provided in Example 1 to prepare wafer protective tape. The difference from Example 1 is that in this embodiment, the grafting rate of maleic anhydride groups of EVA-g-MAH in the reinforcing layer is 5% when preparing the wafer protective tape. Apart from the above differences, the operation steps for preparing the wafer protective tape in this embodiment are strictly consistent with those in Example 1.

[0043] Example 6

[0044] This embodiment refers to the formulation and method provided in Example 1 to prepare wafer protective tape. The difference from Example 1 is that in this embodiment, the grafting rate of maleic anhydride groups of POE-g-MAH in the barrier layer is 16% when preparing the wafer protective tape. Apart from the above differences, the operation steps for preparing the wafer protective tape in this embodiment are strictly consistent with those in Example 1.

[0045] Example 7

[0046] This embodiment refers to the formulation and method provided in Example 1 to prepare wafer protective tape. The difference from Example 1 is that in this embodiment, when preparing wafer protective tape, the grafting rate of maleic anhydride groups of EVA-g-MAH in the barrier layer is 3%, and the grafting rate of maleic anhydride groups of POE-g-MAH is 5%. Apart from the above differences, the operation steps for preparing wafer protective tape in this embodiment are strictly consistent with those in Example 1.

[0047] Example 8

[0048] This embodiment prepares wafer protective tape with reference to the formula and method provided in Embodiment 1. The difference from Embodiment 1 is that no reinforcing layer is set when preparing the wafer protective tape in this embodiment. Apart from the above differences, the operation steps for preparing the wafer protective tape in this embodiment are strictly consistent with those in Embodiment 1.

[0049] Example 9

[0050] This embodiment refers to the formulation and method provided in Example 1 to prepare wafer protective tape. The difference from Example 1 is that in this embodiment, an equal mass fraction of SEBS is used to replace C5-MAH in the preparation of the adhesive layer. Apart from the above differences, the operation steps for preparing wafer protective tape in this embodiment are strictly consistent with those in Example 1.

[0051] Example 10

[0052] This embodiment refers to the formulation and method provided in Example 1 to prepare wafer protective tape. The difference from Example 1 is that in this embodiment, C5-MAH is used in place of SEBS to prepare the adhesive layer in equal parts by mass when preparing the wafer protective tape. Apart from the above differences, the operation steps for preparing the wafer protective tape in this embodiment are strictly consistent with those in Example 1.

[0053] Comparative Example 1

[0054] This comparative example prepares wafer protective tape using the formulation and method provided in Example 1. The difference between this comparative example and Example 1 is that no barrier layer is set when preparing the wafer protective tape. Apart from the above differences, the operation steps for preparing the wafer protective tape in this comparative example are strictly consistent with those in Example 1.

[0055] Comparative Example 2

[0056] This comparative example prepares wafer protective tape using the formulation and method provided in Example 1. The difference between this comparative example and Example 1 is that only EVA-g-MAH is used in the barrier layer when preparing the wafer protective tape. Apart from the above differences, the operation steps for preparing the wafer protective tape in this comparative example are strictly consistent with those in Example 1.

[0057] Comparative Example 3

[0058] This comparative example prepares wafer protective tape using the formulation and method provided in Example 1. The difference between this comparative example and Example 1 is that only POE-g-MAH is used in the barrier layer when preparing the wafer protective tape. Apart from the above differences, the operation steps for preparing the wafer protective tape in this comparative example are strictly consistent with those in Example 1.

[0059] Comparative Example 4

[0060] This comparative example prepares wafer protective tape using the formulation and method provided in Example 1. The difference between this comparative example and Example 1 is that, in preparing the wafer protective tape, the ratio of EVA-g-MAH to POE-g-MAH in the barrier layer is 1:1. Apart from the above differences, the operation steps for preparing the wafer protective tape in this comparative example are strictly consistent with those in Example 1.

[0061] Comparative Example 5

[0062] This comparative example uses Nitto SPV-224SRB blue film, a mature product in this application field. It is made of PVC and has a total thickness of approximately 75μm.

[0063] Test case

[0064] 1. Test Object

[0065] The wafer protective tapes prepared in Examples 1-10 and Comparative Examples 1-5.

[0066] 2. Testing Methods

[0067] (1) Peel strength: The test was conducted in accordance with GBT2792-2014 "180° peel strength of adhesive tape to stainless steel".

[0068] (2) Release film release force test method: The release film is peeled off at 180° using a tensile tester or similar instrument with a release film peeling speed of 300 mm / min and an accuracy of +2%. The test plate is made of glass or smooth stainless steel, and a standard pressure roller (2 kg) is used. The test sample is 25 mm wide and at least 200 mm long along the direction of the instrument. The cut is clean and straight. At least 3 samples of each material should be tested. TESA 7475 test tape is used.

[0069] Test conditions: Temperature 23℃±2℃, 50%RH±5%RH.

[0070] Test Procedure: Place the TESA 7475 adhesive strip face down on a clean test plate with light finger pressure. Use a pressure roller to press back and forth twice at a speed of approximately 10 mm / s to ensure tight contact between the adhesive and the test plate. (For release film testing, either pull the strip back or fix it to the test plate.) After the test strip is applied, allow it to stand for 20 minutes before testing. If peel strength testing is required, allow it to stand for 24 hours. Set the peel angle to 180° and the speed to 300 mm / min, then start the test.

[0071] Test results: The release film peel force is expressed as N / 25MM (1KG=9.81N). The average value is taken for each test strip. The bonding time is 20 minutes or 24 hours.

[0072] (3) Unwinding force: The test was conducted in accordance with ASTM D3811 / D3811M-2019, "Standard Test Method for Unwinding Force of Pressure-Sensitive Adhesive Tape".

[0073] (4) Tensile strength and elongation at break: Tested according to GB / T 30776-2014 "Test methods for tensile strength and elongation at break of adhesive tape".

[0074] (5) Ring initial tack: The test shall be conducted in accordance with GB / T 31125-2014 "Test method for initial tack of adhesive tape - ring method".

[0075] (6) Expanding ratio: Using a mature expanding machine on the market, the basic expanding principle is as follows: The film is fixed on the stage, and the stage surface has a heating system (the commonly used temperature is 40-60℃). It is lifted by air pressure. At this time, the film has a certain temperature, the film will soften and be subjected to the upward force of the stage, and the film will expand evenly in all directions. The expanding ratio is mainly related to the material and thickness of the film itself and the degree of lifting of the expanding machine stage (this data was tested using an expanding machine produced by Xiamen Honghan Electronic Technology Co., Ltd.); Test method: Before expanding the film, draw a circle with a diameter of 6cm in the middle of the film. Use the expanding machine, with the expanding stage surface at 50 degrees Celsius, to expand the film and measure the diameter of the circle after expansion; The formula for calculating the expanding ratio is: Expanding ratio = Diameter of the circle after expansion / Length of the circle before expansion.

[0076] (7) Film expansion shrinkage: The film was expanded by 1.3 times according to the film expansion ratio test method, that is, the initial diameter of the circle was expanded to the diameter of the circle (d1) of 7.8 cm. The expanded film was kept in this state for 10 min, then the film was removed and placed in a free horizontal state at a temperature of 23℃±2℃ without stretching. The diameter of the circle (d2) was observed and recorded after standing for 15s, 30s, 1min, and 2min, and the corresponding shrinkage (cm) was calculated as d1-d2.

[0077] 3. Test Results and Analysis

[0078] The experimental results of this test example are shown in Tables 2 and 3. The appearance of the wafer protective tape prepared in Comparative Example 1 is as follows: Figure 2 As shown, the appearance of the wafer protective tape prepared in Example 1 is as follows. Figure 3 As shown. Observing the appearance of the film surface, it is clear that when no barrier layer is placed between the release layer and the TPU substrate layer, there will be oil stains on the film surface of the wafer protective tape. However, when a barrier layer is placed, the film surface is uniform and no oil stains are observed. In addition, the appearance of the wafer and the dicing marks on the film surface after the wafer protective tape prepared in Example 1 is used to cut the wafer with a dicing knife is as shown. Figure 4 As shown, the appearance of the wafer and film surface marks after the wafer is cut by a dicing knife using the wafer protective tape prepared in Example 6 is as follows. Figure 5 As shown, by observing the chip loss at the wafer edge and the appearance of the cut marks on the film surface, it is clear that without a reinforcing layer between the TPU substrate layer and the adhesive layer, delamination occurs during cutting, posing a risk of chip loss. However, with a reinforcing layer, there are no chips, the cutting marks are clear, and there is no delamination. This demonstrates that the wafer protective tape provided by this invention, by preferably incorporating a reinforcing layer, can further improve wafer yield.

[0079] Furthermore, in this wafer dicing process, a whole wafer is typically diced into smaller chips. To check if dicing is complete and to facilitate subsequent chip packaging and unloading, the diced chips undergo a film expansion process. This expansion process separates each chip along the dicing ridges, creating a gap between them. After expansion, the wafer is laminated, and the chips are transferred to a new film for further chip performance testing and shipping. When the wafer protective tape has high resilience, due to overall expansion and stretching, the film layer will stretch and shrink during the lamination process, reducing the original expansion ratio of the wafer protective tape and decreasing the chip gap. Furthermore, if the shrinkage speed is too fast, the adhesive layer between the film layer and the chip will be stretched by the rebound, reducing the adhesion and causing the chip to fall off, thus decreasing the wafer yield. Compared to the PVC film widely used in this field in Comparative Example 5, in Comparative Example 1, the substrate layer is made of TPU material. TPU has good elasticity and a fast rebound speed, which is significantly faster than PVC, thus making it difficult to ensure wafer processing yield.

[0080] Secondly, in Comparative Examples 2 and 3, using only EVA-g-MAH and POE-g-MAH as barrier layers respectively resulted in varying degrees of decrease in the mechanical properties of the prepared wafer protective tapes, particularly affecting the springback, release force, and unwinding force after film expansion. Specifically, in Comparative Example 2, when only EVA-g-MAH was used as the barrier layer, the shrinkage was similar to that of Comparative Example 1, and the springback after film expansion was relatively fast. In Comparative Example 3, when only POE-g-MAH was used as the barrier layer, delamination occurred during film expansion, and the poor adhesion between TPU and POE-g-MAH led to an increase in release force.

[0081] Furthermore, based on examples 1-3 and comparative example 4, it is evident that the mass ratio of EVA-g-MAH and POE-g-MAH in the barrier layer also affects the mechanical properties of the barrier layer, as well as the expansion ratio, expansion rebound, and release force of the wafer protective tape. Therefore, by comprehensively analyzing the experimental data from examples 1-3 and comparative examples 1-4, it is clear that this invention, by introducing EVA-g-MAH and POE-g-MAH and utilizing their synergistic effect in combination with TPU and silicone release agents, can not only reduce the release force of the wafer protective tape but also reduce the rebound after film expansion, improve the adhesion between the barrier layer and the substrate layer, and thus improve the wafer yield in the actual production casting process.

[0082] In Comparative Example 5, a PVC film commonly used in the art was used. According to the data provided in Example 1, when TPU is applied to the wafer dicing field, it has sufficient elasticity and flexibility, which can provide protection and buffering for the wafer during the dicing process, and can also spread the film evenly.

[0083] In Examples 4 and 5, the EVA-g-MAH used in the barrier layer and reinforcing layer were substituted. Experimental data showed that the grafting rate of maleic anhydride groups in the EVA-g-MAH used in different functional layers also affected the function of the corresponding functional layer. Furthermore, in Examples 1, 4, and 6-7, the grafting rate of maleic anhydride groups in the EVA-g-MAH and POE-g-MAH used in the barrier layer was changed. Experimental data confirmed that in the barrier layer, when the grafting rate of maleic anhydride groups in the maleic anhydride-modified EVA plastic is ≥5% and the grafting rate of maleic anhydride groups in the maleic anhydride-modified POE plastic is ≥8%, the resulting wafer protective tape exhibits better performance.

[0084] In conjunction with Examples 1 and 8, the reinforcing layer can further improve the bonding force between the adhesive layer and the substrate layer, and can improve the delamination and debonding phenomenon of the wafer protective tape during wafer dicing.

[0085] Combined with Examples 1 and 9-10, it can be shown that the adhesive layer, by combining SEBS and maleic anhydride-modified C5 resin, can significantly enhance the adhesion and peel strength of the wafer protective tape, meeting the adhesion requirements during cutting.

[0086] Table 2. Experimental results of this test case

[0087]

[0088] Table 3. Results of film expansion experiment in this test case

[0089]

[0090] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A wafer protective tape, characterized in that, The wafer protective tape comprises a release layer, a barrier layer, a substrate layer, and an adhesive layer arranged sequentially. The release layer and the substrate layer are directly bonded together through the barrier layer. The release layer comprises a silicone release agent, the substrate layer comprises thermoplastic polyurethane elastomer rubber, and the barrier layer comprises maleic anhydride-modified EVA plastic and maleic anhydride-modified POE plastic. The ratio of maleic anhydride-modified EVA plastic to maleic anhydride-modified POE plastic is 2 to 5 times the mass ratio.

2. The wafer protective tape as described in claim 1, characterized in that, In the barrier layer, the maleic anhydride-modified EVA plastic has a maleic anhydride group grafting rate of ≥5%; and / or, the maleic anhydride-modified POE plastic has a maleic anhydride group grafting rate of ≥8%.

3. The wafer protective tape as described in claim 1, characterized in that, The adhesive layer comprises hydrogenated styrene-butadiene block copolymer and maleic anhydride-modified C5 petroleum resin.

4. The wafer protective tape as described in claim 3, characterized in that, In the adhesive layer, the mass ratio of the hydrogenated styrene-butadiene block copolymer to the maleic anhydride-modified C5 petroleum resin is 3~7:

1.

5. The wafer protective tape as described in claim 3, characterized in that, The hydrogenated styrene-butadiene block copolymer is prepared by polystyrene and polybutadiene, and the molar ratio of polystyrene to polybutadiene is (25~35):(65~75).

6. The wafer protective tape as described in claim 1, characterized in that, The wafer protective tape further includes a reinforcing layer; the reinforcing layer is disposed between the substrate layer and the adhesive layer; the reinforcing layer includes the maleic anhydride modified EVA plastic.

7. The wafer protective tape as described in claim 6, characterized in that, In the reinforcing layer, the maleic anhydride group grafting rate of the maleic anhydride modified EVA plastic is 10-12%.

8. The wafer protective tape as described in any one of claims 1 to 7, characterized in that, Based on the thickness ratio, the release layer : the barrier layer : the substrate layer : the adhesive layer = (0.05~0.5) : (5~8) : (55~80) : (6~12).

9. The wafer protective tape as described in claim 8, characterized in that, The thickness of the barrier layer is 5~8μm.

10. The wafer protective tape as described in claim 6, characterized in that, The thickness of the reinforcement layer is 4~8μm.

11. The wafer protective tape according to any one of claims 1 to 7, characterized in that, The wafer protective tape is produced by an extrusion casting process.

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