Adhesive sheet for electronic component manufacturing process

Abstract

The present application discloses an adhesive sheet for use in an electronic component process, the electronic component being adhered to the adhesive sheet for use in a high temperature sputtering process of 100-200 DEG C, the adhesive sheet having an adhesive force (male gram weight / inch) at 25 DEG C measured using the ASTM D1000 specification of A, 40 lt; alt; 250, and the adhesive force (gram weight per inch) measured at 80 DEG C after being heated to 80 DEG C is B, Blt; 30. The adhesive sheet comprises: a polyimide film; the pressure sensitive adhesive is adhered to the polyimide film, log (Tan (delta) / 25 DEG C), measured by a rheometer at 25 DEG C, of the pressure sensitive adhesive is X, log (Tan (delta) / 50 DEG C), measured by the rheometer at 50 DEG C, of the pressure sensitive adhesive is Y, and Y-Xlt; and-0.01, so that the electronic component can be easily taken down from the adhesive sheet at the temperature of 80-100 DEG C after being subjected to a high-temperature sputtering coating process, and the micro-structure surface has no pollution phenomena of overflow coating and residual glue.

Description

Technical Field

[0001] The present application relates to the technical field of electronic components, and in particular to an adhesive sheet used in the manufacturing process of electronic components. Background Art

[0002] In the prior art, adhesive materials such as adhesive sheets have been widely used in the production process of various products (such as semiconductor-related components). Specifically, general electronic components are provided with a metal layer to prevent electromagnetic interference. The electronic components need to undergo a high-temperature (100-200°C) sputtering process. Due to the process design, a carrier such as an adhesive sheet must be provided to carry the electronic components. In order to prevent the sputtered metal from being plated onto the microstructure surface (such as the electronic component electrode or pin) during the process and causing component failure (hereinafter referred to as overflow plating), the adhesive force of the adhesive sheet must be sufficient to fix the electronic component to each other and not separate from the electronic component during the sputtering process, that is, no peeling occurs. In addition, after the electronic component has undergone the sputtering process, during the pick-up step, the adhesive sheet needs to be separated from the electronic component, and there should be no residual glue on the microstructure surface.

[0003] Therefore, the adhesive sheet required for the high temperature sputtering process for sputtering the metal layer of the electronic component needs to have good adhesion and the characteristics of being easy to peel off after the sputtering process without residual adhesive on the microstructure surface of the electronic component.

[0004] According to the prior art, in the conventional adhesive sheet products used to adhere electronic components, after the high temperature process, the adhesion between the adhesive sheet and the electronic components will increase. Therefore, it is difficult to peel the adhesive sheet and the electronic components, or the peeling transfer pollution of the electronic components increases, thereby generating problems such as residual adhesive.

[0005] In order to solve the above problems, many documents have mentioned that during the separation process of the adhesive sheet and the adhered object, a heating device can be used to peel the adhesive sheet and the adhered object at a temperature higher than room temperature (25°C). For example, document "TWM588877U" mentioned that using a heating unit to heat can reduce the bonding force between the adhesive sheet (called adhesive film in the document) and the adhered object (called substrate in the document).

[0006] According to current technology, many electronics factories also use hot air blowing or hot plates to reduce the adhesion between the adhesive sheet and the object when the adhesive sheet needs to be separated from the object during the process of using adhesive sheets, thereby increasing production efficiency or reducing the risk of residual adhesive.

[0007] In summary, if one desires to develop an adhesive sheet for high-temperature (100 - 200 °C) sputtering processes, after the adhesive sheet carrying the electronic component undergoes the sputtering process, during the separation stage of the electronic component and the adhesive sheet, through a heating step, it is beneficial for the separation of the electronic component and the adhesive sheet without the generation of residual glue contamination at a temperature higher than room temperature (25 °C).

[0008] However, upon examining the currently known art, there is no clear indication of what kind of quantitative characterization is used to select a suitable adhesive sheet to achieve such an effect.

[0009] In view of this, in the existing technology, there is still room for improvement in the production of adhesive sheets for electronic component processes. Summary of the Invention

[0010] To address the above deficiencies in the art, the present application aims to provide an adhesive sheet for electronic component processes.

[0011] The electronic component is adhered to the adhesive sheet, which is used for high-temperature sputtering processes at 100 - 200 °C. The adhesive force (gram weight per inch) of the adhesive sheet measured at 25 °C using ASTM D1000 specification is A, where 40 < A < 250, and after it is heated to 80 °C, the adhesive force (gram weight per inch) measured at 80 °C is B, where B < 30.

[0012] The adhesive sheet includes: a polyimide film; and a pressure-sensitive adhesive adhered to the polyimide film. The log(Tan(δ) / 25 °C) of the pressure-sensitive adhesive measured at 25 °C using a rheometer is X, and the log(Tan(δ) / 50 °C) measured at 50 °C is Y, where Y - X < -0.01.

[0013] The electronic component is placed on the pressure-sensitive adhesive for bonding and fixing, and then a metal layer for electromagnetic interference prevention is provided through high-temperature sputtering at 100 - 200 °C. Next, the electronic component with the metal layer can be easily removed from the adhesive sheet under the provision of a heat source (such as 80 - 100 °C), and there is no over-sputtering or residual glue contamination on the microstructural surface.

[0014] To enable a further understanding of the features and technical content of the present invention, please refer to the following detailed description of the present invention and the attached drawings. However, the provided drawings are only for reference and illustration and are not used to limit the present invention. Brief Description of the Drawings

[0015] Figure 1 It is the first schematic diagram of the adhesive sheet for electronic component processes of the present invention.

[0016] Figure 2 It is the second schematic diagram of the adhesive sheet for electronic component processes of the present invention.

[0017] Figure 3 The third schematic diagram of the adhesive sheet for electronic component manufacturing in the present invention

[0018]

Symbol description

[0019] Polyimide film 10

[0020] Pressure-sensitive adhesive 12

[0021] Electronic component 14

[0022] Metal layer 16

[0023] Microstructure surface 18 Detailed implementation manners

[0024] Next, the technical solutions of the present application will be clearly and completely described in conjunction with the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present application.

[0025] It should be particularly noted that similar replacements and modifications made to the present application are obvious to those skilled in the art, and they are all regarded as included in the present application. Relevant personnel can obviously make changes or appropriate alterations and combinations to the methods and applications described herein without departing from the content, spirit and scope of the present application to implement and apply the technology of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0026] Unless otherwise specified in the present application, all are carried out according to conventional conditions or conditions recommended by the manufacturer. For the raw materials or excipients used, and for the reagents or instruments used, unless the manufacturer is specified, they are all conventional products that can be obtained commercially.

[0027] Next, the present application will be described in detail.

[0028] Figure 1 The first schematic diagram of the adhesive sheet for electronic component manufacturing in the present invention. The adhesive sheet includes: a polyimide film 10; and a pressure-sensitive adhesive 12, which is adhered to the polyimide film 12. An electronic component 14 is placed on the pressure-sensitive adhesive 12 for fitting and fixing.

[0029] The adhesive force (gram weight / inch) of the adhesive sheet measured using ASTM D1000 standard at 25°C is A, where 40 < A < 250, and after it is heated to 80°C, the adhesive force (gram weight / inch) measured at 80°C is B, where B < 30.

[0030] The log(Tan(δ) / 25°C) of the pressure-sensitive adhesive 12 measured by a rheometer at 25°C is X, and the log(Tan(δ) / 50°C) measured at 50°C is Y, where YX<-0.01.

[0031] Figure 2 This is a second schematic diagram of the adhesive sheet used in the electronic component manufacturing process of the present invention. After the electronic component 14 is attached to the adhesive sheet 12, the electronic component 14 is subjected to high temperature sputtering at 100-200°C to form a metal layer 16.

[0032] Figure 3 This is a third schematic diagram of the adhesive sheet used in the electronic component manufacturing process of the present invention. After the electronic component 14 is sputtered with a metal layer 16, a heat source (such as 80-100° C.) is provided to separate the electronic component 14 with the metal layer 16 from the adhesive sheet, and it is observed that there is no contamination such as overflow plating or residual glue on the microstructure surface 18.

[0033] The polyimide film 10 is used as a support for the pressure-sensitive adhesive 12 , and the thickness thereof may be between 5 and 300 μm, preferably between 12.5 and 200 μm.

[0034] In addition, the polyimide film 12 can be well bonded more closely with the pressure-sensitive adhesive by performing surface treatment.

[0035] For example, the polyimide film may be subjected to physical treatment, chemical treatment, or both. The treatment methods may include light treatment, corona discharge, undercoat treatment, coating treatment, cross-linking treatment, chromic acid treatment, ozone exposure, flame exposure, high voltage electric shock exposure, and ionizing radiation treatment.

[0036] The pressure-sensitive adhesive 14 in the adhesive sheet provided in the embodiment of the present invention can be formed on the surface of the polyimide film 10 by a coating step. There are many coating methods, which are also known technologies and will not be repeated here. There is no special limitation in this invention. The embodiment uses comma coating as an option.

[0037] In the present invention, the thickness of the pressure-sensitive adhesive 12 can be in the range of 1 to 500 micrometers (μm). In practice, in order to ensure the adhesion of the adhesive sheet, the thickness of the pressure-sensitive adhesive 12 must be greater than 1 micrometer. Generally speaking, the microstructure surface will have some height differences, such as electrodes, pins, solder balls, circuits or alloy bumps. In order to ensure the compliance of the pressure-sensitive adhesive of the adhesive sheet and the electronic components, the thickness of the pressure-sensitive adhesive must have a height difference greater than the microstructure surface.

[0038] It is known from the theory that the general pressure-sensitive adhesive 12 has the phenomenon that the adhesion under certain heating conditions is lower than the adhesion at room temperature (25°C), for example, A>B (the definitions of A, B, X, and Y have been mentioned above). The only difference is that different pressure-sensitive adhesive systems or formulations lead to different A, B, X, and Y (X and Y are rheological properties). In response to various applications, it is necessary to find a suitable relationship and range of A, B, X, and Y. As described in the present invention, an adhesive sheet for electronic component manufacturing process needs to find a suitable relationship and range of A, B, X, and Y, so that the electronic component 14 can be easily removed from the adhesive sheet under heating conditions after the process, and there is no contamination of overflow plating or residual adhesive on the microstructure surface.

[0039] Based on the above, the system of the pressure-sensitive adhesive 12 is not particularly limited in this invention, and can be rubber-based, acrylic-based, vinyl-alkyl ether-based, polysiloxane-based, polyester-based, polyamide-based, urethane-based, polystyrene / diene copolymer-based, and acrylic (ester) copolymer-based. The embodiments and comparative examples are only examples of suitable and unsuitable A, B, X, and Y results, and are not limiting. More specifically, the acrylic ester adhesive mentioned in the case has models: PC-53, PC-57, PC-42, PC-47, PC-32, PC-33, PC-34, PC-98, and PC-75, and the model of the polyisocyanate crosslinking agent: M, which is only an example to illustrate how to implement.

[0040] In order to enhance the cohesion of the pressure-sensitive adhesive and strengthen its physical properties (such as heat resistance, acid and alkali resistance, weather resistance, etc.), a cross-linking agent is generally added. However, different pressure-sensitive adhesive systems correspond to different cross-linking agent systems. Since this is a conventional technology, no further examples will be given here.

[0041] As in the embodiment, the system of the pressure-sensitive adhesive 12 is selected to be an acrylic adhesive in combination with a polyisocyanate cross-linking agent to achieve an ideal cross-linking degree. An appropriate ratio is selected for mixing. However, it is known that in general, the optimization of the cross-linking degree is related to various formulas, compositions and matching degrees, and is not limited in the present invention. In some embodiments of this invention, the content of the polyisocyanate cross-linking agent added is selected based on 100% by weight of the acrylic adhesive.

[0042] The adhesive sheet provided by the present invention can have different shapes. Specifically, the adhesive sheet can be a sheet of adhesive material, or an adhesive material rolled into a roll. In addition, the shape of the adhesive sheet can be adjusted according to the application field, the type of product to be adhered, or other parameters of the manufacturing process, and the present invention is not limited here.

[0043] In the present invention, the height difference of the microstructure surface of the electronic component may be in the range of 0.3 to 300 μm.

[0044] The temperature applicable to the high temperature sputtering process in the present invention may be in the range of 100-200°C, and the sputtered metal is not limited in the present invention. A metal layer that prevents electromagnetic interference can be achieved by using different machines, different palladium materials and sputtering different metals.

[0045] In order to avoid the contamination of residual adhesive on the microstructure surface when removing the electronic component 14 from the adhesive sheet, the temperature during the removal process is too high, which causes the internal stress of the pressure-sensitive adhesive 12 to increase. Therefore, during the separation of the electronic component from the adhesive sheet, the required temperature must be lower than the sputtering temperature. However, if the required temperature is too low, it will be difficult to remove. Specifically, after the electronic component has completed the sputtering process, it can be easily removed from the adhesive sheet at 80-100°C; the preferred temperature is 85-90°C.

[0046] Regardless of the above sputtering process or when the electronic component 14 is separated from the adhesive sheet, temperature is required, and the heat source can be radio waves, electron beams, infrared rays, visible rays, ultraviolet rays, X-rays or gamma rays. However, the heating method (i.e., the method of providing the heat source) of the present invention is not limited thereto and can also be provided by a hot air oven, a halogen lamp, microwave heating, a stove or steam heat conduction.

[0047] The implementation methods of the present invention are as follows:

[0048] Acrylate adhesives and polyisocyanate crosslinking agents are provided by Xinzong Industrial Co., Ltd. The types of acrylate adhesives are: PC-53 (viscosity: 3000-5000cps; SC: 29-31%), PC-57 (viscosity: 3000-4500cps; SC: 30-32%), PC-42 (viscosity: 4000-8000cps; SC: 49-51%), PC-47 (viscosity: 3000-6000cps; SC: 44-46%), PC-32 (viscosity: 3000-5000cps; SC: 34-3 6%), PC-33 (viscosity: 2000-4000cps; SC: 30-32%), PC-34 (viscosity: 4000-7000cps; SC: 39-41%), PC-98 (viscosity: 4000-6000cps; SC: 34-36%) and PC-75 (viscosity: 3000-6000cps; SC: 29-31%), a total of 9 types, the polyisocyanate crosslinking agent is toluene diisocyanate (TDI) series, model: M (viscosity: 1000-2500cps; SC: 73-77%), and the formation method of the pressure-sensitive adhesive is as follows:

[0049] After adding 120 kg of acrylic adhesive to a 180-liter (180 L) tank equipped with a thermometer, stirring rod, and stirring blades, a polyisocyanate crosslinking agent is slowly added. The amount of polyisocyanate crosslinking agent added is selected based on 100% by weight of acrylic adhesive and is described in detail in the case.

[0050] Next, the mixture was stirred in the above-mentioned apparatus for 30 minutes and then vacuum degassed for 1 hour to obtain a formulation of a pressure-sensitive adhesive.

[0051] The obtained pressure-sensitive adhesive 12 is coated on the polyimide film 10 using a comma coating machine and dried in an oven (four oven compartments, temperature settings: 70°C / 80°C / 110°C / 120°C, production speed: 5 m / min). The appropriate coating gap is adjusted to obtain a pressure-sensitive adhesive 12 with a thickness of 30 μm.

[0052] The testing method of the present invention is as follows:

[0053] Adhesion A (grams / inch) (25°C): First, cut the width and length of the adhesive sheet to be tested (width: 1 inch, length about 25 cm), use a handheld 2 kg rolling roller to fix the adhesive sheet on a polished steel plate, and press it back and forth. The stainless steel plate specification is 5×15 cm, and let it stand for 20 minutes. Fix the steel plate on the adhesion tester, peel it at 25°C at a peeling speed of 300mm / min and a peeling angle of 180 degrees, and measure the adhesion A (grams / inch) (25°C). The entire process complies with ASTM D1000 specifications.

[0054] Adhesion B (grams / inch) (80°C): The operation is similar to Adhesion A (grams / inch) (25°C), except that the steel plate needs to be heated to 80°C before the peel test.

[0055] YX: Use a dynamic viscoelasticity measuring device (rheometer) to measure the object to be tested. The fixture uses a parallel disc plate with a diameter of 8mm. The pressure-sensitive adhesive is measured at a frequency of 1rad / sec at 25℃ to obtain log(Tan(δ) / 25℃), which is X. Also, measure log(Tan(δ) / 50℃) at 50℃, which is Y. Record the data of YX.

[0056] After the sputtering process, observe the adhesion between the adhesive sheet and the electronic component 14: use visual observation and record.

[0057] After the sputtering process, the electronic component 14 was removed from the adhesive sheet at 80°C to observe the residual adhesive of the component: observe and record using a digital microscope. (Magnification: 20X) (If it cannot be removed, no observation will be performed, such as in Comparative Example 2)

[0058] After the sputtering process, remove the electronic components from the adhesive sheet at 80°C and observe the over-plating status of the components: observe and record using a digital microscope (magnification: 20X) (If it cannot be removed, no observation will be performed, such as Comparative Example 2)

[0059] The cases of the present invention are as follows:

[0060] Example 1: Formula of pressure-sensitive adhesive 12: PC-53+0.25% M; coating substrate: polyimide film 10.

[0061] Example 2: Formula of pressure-sensitive adhesive 12: PC-57+0.38% M; coating substrate: polyimide film 10.

[0062] Example 3: Formula of pressure-sensitive adhesive 12: PC-42+0.16% M; coating substrate: polyimide film 10.

[0063] Example 4: Formula of pressure-sensitive adhesive 12: PC-47+0.22% M; coating substrate: polyimide film 10.

[0064] Example 5: Formula of pressure-sensitive adhesive 12: PC-32+0.19% M; coating substrate: polyimide film 10.

[0065] Comparative Example 1: Formula of pressure-sensitive adhesive 12: PC-33+0.82%M; coating substrate: polyethylene terephthalate

[0066] Comparative Example 2: Formula of pressure-sensitive adhesive 12: PC-34+0.62% M; coating substrate: polyimide film 10.

[0067] Comparative Example 3: Formula of pressure-sensitive adhesive 12: PC-98+0.52% M; coating substrate: polyimide film 10.

[0068] Comparative Example 4: Formula of pressure-sensitive adhesive 12: PC-75+0.38% M; coating substrate: polyimide film 10.

[0069] Comparison of Examples and Comparative Examples

[0070]

[0071] The comparative examples are described as follows:

[0072] Comparative Example 1: Since the substrate used is polyethylene terephthalate, which is less heat-resistant than polyimide film, after a high-temperature (100-200°C) sputtering process, the adhesive sheet and the electronic component will not be completely adhered, resulting in overflow of the component when the electronic component is removed from the adhesive sheet at 80°C.

[0073] Comparative Example 2: Since it does not meet the requirement of this case "Y - X < -0.01", after the high-temperature (100 - 200 °C) sputtering process, at 80 °C, B is measured to be 37, and this adhesion force does not meet "B < 30", that is, it is difficult to remove the electronic component from the adhesive sheet.

[0074] Comparative Example 3: Since A is measured to be 261, which does not meet the requirement of this case "40 < A < 250", after the high-temperature (100 - 200 °C) sputtering process, at 80 °C, when the electronic component is removed from the adhesive sheet, it can be observed that there is residual glue on the component.

[0075] Comparative Example 4: Since A is measured to be 32, which does not meet the requirement of this case "40 < A < 250", after the high-temperature (100 - 200 °C) sputtering process, at 80 °C, when the electronic component is removed from the adhesive sheet, it can be observed that there is overplating on the component.

[0076] The description of the above embodiments is only used to help understand the method and its core idea of this application. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of this application, several improvements and modifications can be made to this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

Claims

1. An adhesive sheet for electronic component manufacturing process, characterized in that: The electronic component is adhered to the adhesive sheet; The electronic component is used in a high-temperature sputtering process at 100 to 200 °C; the adhesive force of the adhesive sheet at 25 °C is A, 40 < A < 250, and the adhesive force of the adhesive sheet measured at 80 °C is B, B < 30; The adhesive sheet includes: A polyimide film; and A pressure-sensitive adhesive adhered to the polyimide film, where log(Tan(δ) / 25 °C) of the pressure-sensitive adhesive at 25 °C is X, and log(Tan(δ) / 50 °C) at 50 °C is Y, and Y - X < -0.

01.

2. The adhesive sheet for electronic component manufacturing process according to claim 1, characterized in that: The pressure-sensitive adhesive is selected from: rubber-based, propylene-based, vinyl-alkyl ether-based, polysiloxane-based, polyester-based, polyamide-based, urethane-based, polystyrene / diene copolymer-based, or acrylic (ester) copolymer-based.

3. The adhesive sheet for electronic component manufacturing process according to claim 1, characterized in that: The thickness of the polyimide film is 5 - 300 μm.

4. The adhesive sheet for electronic component manufacturing process according to claim 3, characterized in that: The thickness of the polyimide film is 12.5 - 200 μm.

5. The adhesive sheet for electronic component manufacturing process according to claim 1, characterized in that: The thickness of the pressure-sensitive adhesive is 1 - 500 μm.

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