A type of tape for grinding semiconductor wafers

Abstract

This utility model discloses an adhesive tape for semiconductor wafer polishing, comprising a PET substrate, a composite base film, and a frame adhesive layer, as well as a small-molecule undercoating layer. The composite base film is laminated onto the PET substrate via the undercoating layer, and the frame adhesive layer is laminated onto the composite base film via coating. This semiconductor wafer polishing tape is rationally designed. The small-molecule undercoating layer added to the substrate via coating provides strong adhesion. Subsequently, the polyolefin composite base film and frame adhesive layer are prepared by coating, effectively reducing manufacturing costs and ensuring good product consistency.

Description

Technical Field

[0001] This utility model relates to the field of adhesive tape technology, and in particular to an adhesive tape for grinding semiconductor wafers. Background Technology

[0002] With the rapid development of semiconductor products, the demand for semiconductor-grade adhesive tapes is urgent. Currently, semiconductor-grade adhesive tapes are mainly prepared by brushing or co-extrusion; however, the manufacturing equipment requires high precision and is difficult to position accurately, resulting in high tape costs.

[0003] For example, patent CN110272696A discloses an adhesive tape for back-side grinding, which has a substrate and a semiconductor wafer with an intermediate resin layer and an adhesive layer sequentially formed on the substrate. The intermediate resin layer has a storage modulus of 0.15×106 to 1.51×106 Pa at any temperature of 55 to 80°C. The adhesive layer is composed of a non-curing adhesive containing an acrylic adhesive polymer as the main component, which has an acid value of less than 2.0 mg KOH / g and a hydroxyl value of 1.0 to 15.0 mg KOH / g. The intermediate resin layer is directly extruded together with the substrate, which results in a relatively high cost. Utility Model Content

[0004] To address the shortcomings of existing technologies, this invention provides a semiconductor wafer grinding tape that adds a base coating layer through a coating process, effectively reducing manufacturing costs.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: The semiconductor wafer grinding tape includes a PET substrate, a composite base film, and a frame adhesive layer, as well as a small molecule base coating layer. The composite base film is laminated onto the PET substrate through the base coating layer, and the frame adhesive layer is laminated onto the composite base film through a coating process.

[0006] Further or preferred: The base coating is applied to the PET substrate by coating.

[0007] The composite base film is coated onto the base layer.

[0008] The thickness of the PET substrate ranges from 20 to 50 μm.

[0009] The thickness of the base coating ranges from 5 to 15 μm.

[0010] The thickness of the composite base film ranges from 70 to 150 μm.

[0011] The thickness of the frame adhesive layer ranges from 10 to 40 μm.

[0012] Compared with the prior art, this utility model has the following advantages: This semiconductor wafer grinding tape is rationally designed. It adds a small-molecule base layer to the substrate through coating, which can provide strong adhesion. Then, a polyolefin composite base film and frame adhesive layer are prepared by coating, which effectively reduces the preparation cost and has good product consistency. Attached Figure Description

[0013] The following is a brief explanation of the contents of each of the accompanying drawings and the markings in the drawings: Figure 1 This is a schematic diagram of the finished roll structure of the tape of this utility model.

[0014] Figure 2 This is a schematic diagram of the single-piece adhesive tape structure of this utility model.

[0015] In the picture: 1. PET substrate, 2. base coating, 3. composite base film, 4. frame adhesive layer. Detailed Implementation

[0016] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings and through the description of the examples.

[0017] like Figure 1 and Figure 2 As shown, the semiconductor wafer grinding tape includes a PET substrate 1, a composite base film 3, a frame adhesive layer 4, and a small molecule base coating layer 2; the composite base film is laminated onto the PET substrate through the base coating layer, and the frame adhesive layer is laminated onto the composite base film through a coating process.

[0018] Preferably, the thickness of the PET substrate 1 ranges from 20-50 μm; the thickness of the base coating layer ranges from 5-15 μm; the thickness of the composite base film ranges from 70-150 μm; and the thickness of the frame adhesive layer ranges from 10-40 μm. The base coating layer is coated onto the PET substrate, the composite base film is coated onto the base coating layer, and finally, the frame adhesive layer is coated onto the composite base film to form an integral tape.

[0019] The PET substrate provides sufficient tensile strength and stiffness; the base coating is a small molecule polyolefin that provides strong adhesion; the composite base film is a high-toughness polyolefin film that can undergo elastic deformation under vacuum negative pressure; and the frame adhesive is a rigid, high-temperature resistant polyimide pressure-sensitive adhesive.

[0020] Preparing the polyolefin base film by coating can maintain a more uniform thickness of the substrate and prevent delamination during stretching; preparing the frame adhesive layer by coating can maintain the uniformity of the adhesive surface and smaller thickness tolerance; preparing the frame adhesive by die-cutting can more accurately control the distance between each frame.

[0021] This invention relates to a semiconductor wafer grinding tape with a reasonable design. A small-molecule base layer is added to the substrate through coating, which can provide strong adhesion. Then, a polyolefin composite base film and frame adhesive layer are prepared by coating, which effectively reduces the preparation cost and produces products with good consistency.

[0022] Preferred specific examples are: like Figure 1 As shown, the semiconductor wafer grinding tape includes, from bottom to top, a PET substrate, a base coating, a composite base film, and a frame adhesive layer; the composite base film is a polyolefin layer, and the frame adhesive layer is a polyimide adhesive layer.

[0023] The preferred PET substrate is a transparent film with a thickness of 38μm, which has high tensile strength, high stiffness, and good support.

[0024] The base coating is applied to the PET substrate using a small molecule polyolefin material coating method. The small molecule polyolefin can improve the adhesion of the PET substrate and improve the adhesion effect of polyolefin to PET. The thickness of the base coating is preferably 10μm, which can improve the adhesion.

[0025] The polyolefin adhesive layer is made by dissolving low-density, high-toughness polyolefin particles with certain temperature resistance in xylene to form an adhesive, which is then applied in two coats. A single coat achieves a thickness of 70μm, while two coats can reach a thickness of 140μm. The four oven temperature settings are 125℃, 135℃, 145℃, and 125℃, with a machine speed of 0.5m / min, ensuring complete drying of the adhesive layer.

[0026] The polyimide adhesive layer is achieved by directly coating the polyolefin layer with a rigid polyimide adhesive. The coating thickness is 30μm, ensuring that the adhesive layer retains its adhesion and rigidity at high temperatures.

[0027] like Figure 2 As shown, single-piece adhesive tape is prepared using a flat die-cutting method. The square frame has a side length of 291mm, an outer diameter of 271mm, an inner outer diameter of 167mm, a ring width of 10mm, a tangent width of 14mm, and an angle of 45° between the center and the vertical diameter at the tangent. The polyimide adhesive layer of the inner ring serves as the adhesive layer and needs to have a certain rigidity to ensure that the tape does not creep when applied. The tangent of the ring serves as the positioning layer to ensure accurate identification of the bonding position. The gray polyolefin layer contacts the wafer; under negative pressure, the grains are embedded in the polyolefin layer. The polyolefin layer needs to be flexible to ensure that it can deform without detaching from the substrate.

[0028] The above description is only a preferred embodiment of the present utility model. The above technical features can be arbitrarily combined to form multiple embodiments of the present utility model.

[0029] The present invention has been described above with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the concept and technical solution of the present invention, or the direct application of the concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A tape for grinding semiconductor wafers, comprising a PET substrate, a composite base film, and a frame adhesive layer, characterized in that: It also includes a small molecule base coating layer, wherein the composite base film is laminated onto the PET substrate through the base coating layer, and the frame adhesive layer is laminated onto the composite base film through a coating process.

2. The semiconductor wafer grinding tape as described in claim 1, characterized in that: The base coating is applied to the PET substrate by coating.

3. The semiconductor wafer grinding tape as described in claim 2, characterized in that: The composite base film is coated onto the base layer.

4. The semiconductor wafer grinding tape as described in claim 3, characterized in that: The thickness of the PET substrate ranges from 20 to 50 μm.

5. The semiconductor wafer grinding tape as described in claim 3, characterized in that: The thickness of the base coating ranges from 5 to 15 μm.

6. The semiconductor wafer grinding tape as described in claim 3, characterized in that: The thickness of the composite base film ranges from 70 to 150 μm.

7. The semiconductor wafer grinding tape as described in claim 3, characterized in that: The thickness of the frame adhesive layer ranges from 10 to 40 μm.

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