Protective film, method for applying same, and method for manufacturing semiconductor components

Abstract

To provide an attachment method of a protection film which can inhibit occurrence of failure caused by a step on a major surface of a semiconductor wafer, and to provide a manufacturing method of the semiconductor component.SOLUTION: An attachment method includes: an arrangement step S1 in which a protection film 20 is disposed so as to cover a major surface 10A of a semiconductor wafer 10; and an attachment step S2 in which the protection film 20 is pressed against the major surface 10A to be attached thereto. The major surface 10A has: a first area 12 in which bumps 11 are disposed; and a second area 13 which includes at least a part of a peripheral edge of the major surface 10A and in which the bumps 11 are not disposed. The attachment step S2 includes a compression step S3 in which the protection film 20 is compressed in a thickness direction. The compression step S3 is performed using a pressing member 32 for pressing the protection film 20 against the major surface 10A and a support member 33 installed along an outer peripheral edge of the second area 13.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a protective film for adhering a protective film to a main surface of a semiconductor wafer when manufacturing semiconductor components from the semiconductor wafer, a method for adhering the protective film, and a method for manufacturing semiconductor components including the method for adhering the protective film. [Background technology]

[0002] When a semiconductor wafer has a main surface on which circuits and the like are formed and a back surface on the opposite side of the main surface, the back surface is polished to a desired thickness in a back-grinding process during the manufacture of semiconductor components. This back-grinding process is carried out by adhering a protective film to the main surface of the semiconductor wafer and fixing the main surface to a chuck table by suction with the protective film interposed therebetween. The protective film described above has a base layer and an adhesive layer. A common method for adhering this protective film is to place the protective film on the main surface of the semiconductor wafer so that the adhesive layer is in contact with the main surface, and then apply a predetermined force to the base layer using a laminating roller or the like to press the adhesive layer against the main surface. In recent years, due to the demand for higher density of semiconductor components, many semiconductor wafers have bumps or microelectromechanical systems (MEMS) on their main surfaces, making the main surfaces uneven. When the above-mentioned general protective film adhering method is used on such an uneven main surface, the surface of the protective film pressed against the main surface becomes uneven following the unevenness of the main surface, causing various problems. Therefore, protective films have been proposed that incorporate an unevenness-absorbing resin layer or a step-absorbing layer to improve unevenness-following ability and thereby reduce the occurrence of unevenness on the surface (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-17239 Summary of the Invention [Problem to be solved by the invention]

[0004] In the semiconductor wafers described above, bumps and the like are not necessarily provided over the entire area of ​​the main surface. In other words, some semiconductor wafers have both uneven areas with bumps and flat areas without bumps on the main surface. For example, some semiconductor wafers have an area on the periphery of their main surface that is intentionally left without bumps for the purpose of engraving a serial number or a manufacturing number (see "symbol 13B" in Figure 1(a)). Then, on the main surface of the semiconductor wafer, a step occurs between the uneven region and the flat region, with the uneven region being high and the flat region being low.

[0005] FIG. 8 is an explanatory diagram showing a case where a protective film 20 is attached to a semiconductor wafer 10 having the above-described step on its main surface 10A by a general attachment method. The protective film 20 has a resin volume (hereinafter also referred to as "thickness") that is more than sufficient to absorb the unevenness caused by the bumps 11 in the first region 12 due to the unevenness absorption layer 23, but the thickness is insufficient to fill the step between the first region 12 and the second region 13, and the step may not be completely filled. In particular, the second region 13 provided on the main surface 10A for the purpose of engraving the above-mentioned serial number or manufacturing number is large in size (area occupied on the main surface 10A), and the amount of thickness of the protective film 20 is significantly insufficient to fill the step with the entire second region 13 of this size. Furthermore, as shown by the arrow in Figure 8, the thick portion of the protective film 20 (irregularity absorption layer 23) flows outward beyond the periphery of the main surface 10A of the semiconductor wafer 10, but general adhesion methods do not have a means to regulate this flow of the thick portion.

[0006] Therefore, since the thickness of the protective film 20 is insufficient to fill the step in the second region 13, defects 24 such as dents or depressions that follow the step are formed on the surface of the protective film 20. When the main surface is fixed by suction in the back-grinding process described above, the protective film 20 is raised from the chuck table at the defect 24, making the vacuum more likely to be broken, which may cause a vacuum error in the back-grinding process, i.e., failure to suction the semiconductor wafer to the chuck table. Even if no vacuum error occurs, the protective film 20 will be raised from the chuck table at the defect 24, and will not be able to fully withstand the external force applied from the backside during the back-grinding process. This may result in cracks, breaks, or invisible microcracks in the semiconductor wafer after the back-grinding process.

[0007] As described above, steps occurring on the main surface of a semiconductor wafer cannot be filled by a general protective film application method, even when a protective film provided with an irregularity-absorbing resin layer, etc. is used. As a result, depressions, dents, etc. following the steps are formed on the surface of the protective film, which causes problems such as vacuum errors and cracks during the back-grinding process.

[0008] The present invention has been made in consideration of the above problems, and provides a protective film that can suppress the occurrence of defects caused by steps on the main surface of a semiconductor wafer, a method for applying the same, and a method for manufacturing semiconductor components. [Means for solving the problem]

[0009] The present invention provides the following means for solving the above problems. [1] A first aspect of the present invention provides a method for adhering a protective film, the method comprising: a positioning step of arranging a protective film so as to cover a main surface of a semiconductor wafer; and a bonding step of pressing the protective film against the main surface to bond the protective film thereto, the main surface has a first region in which bumps are arranged and a second region which is a region including at least a part of the periphery of the main surface and in which no bumps are arranged; the attaching step includes a compressing step of compressing the protective film in its thickness direction, The compression step is performed using a pressing member for pressing the protective film against the main surface and a support member installed along the outer periphery of the second region.

[0010] [2] In the method for attaching a protective film according to the first aspect of the present invention, the arranging step is a step of arranging the protective film so that an edge of the protective film extends outward from the periphery of the second region, The compressing step may be a step of compressing the edge portion by supporting the edge portion on the support member and sandwiching the edge portion between the support member and the pressing member. [3] In the method of attaching a protective film of the first invention, the support surface of the support member that supports the edge portion of the protective film can be parallel to the main surface or inclined so as to face the main surface. [4] In the method of adhering a protective film of the first invention, when the clearance between the main surface of the semiconductor wafer and the pressing surface of the pressing member is C1 and the clearance between the support surface of the support member and the pressing surface of the pressing member is C2, C1 can be made to be greater than C2. [5] In the method for attaching a protective film of the first invention, the positioning step can be a step of positioning the protective film so that the edge of the protective film is located more inward than the support member, and the compression step can be a step of blocking the bulging of the second region of the protective film toward the periphery by the inner surface of the support member, which occurs when the protective film is sandwiched between the pressing member and the main surface, and compressing the edge between the pressing member, the inner surface of the support member, and the main surface.

[0011] [6] In the method for adhering a protective film according to the first aspect of the present invention, the protective film may have a layer that can exhibit fluidity or plasticity. [7] In the method for adhering a protective film according to the first aspect of the present invention, the compressing step can be carried out in a state in which the protective film has been heated to develop the fluidity or plasticity. [8] In the method for adhering a protective film according to the first aspect of the present invention, when the average height of the bumps is H1 and the average thickness of the protective film is H2, the ratio H2 / H1 can be 0.5≦H2 / H1. [9] The second aspect of the present invention is a method for manufacturing a semiconductor component, which includes the method for attaching a protective film according to the first aspect of the present invention.

[10] The protective film of the third invention is summarized as being used in the method for adhering the protective film of the first invention.

[0012]

[11] A protective film attachment method according to a fourth aspect of the present invention includes a processing step of processing a protective film to obtain a processed film; a placement step of placing the processed film so as to cover a main surface of a semiconductor wafer; a bonding step of pressing the processed film against the main surface to bond the film, the main surface has a first region in which bumps are arranged and a second region which is a region in which bumps are not arranged and which includes at least a part of the periphery of the main surface; the processing step is a step of forming portions of different thicknesses in the protective film to obtain the processed film, The gist of the method is that the arranging step is a step of arranging a relatively thick region of the portions of the processed film having different thicknesses so as to correspond to the second region.

[12] In the method for adhering a protective film according to the fourth aspect of the present invention, the protective film may have a layer that can exhibit fluidity or plasticity.

[13] In the method for adhering a protective film according to the fourth aspect of the present invention, the processing step can be carried out in a state in which the protective film is heated to develop the fluidity or plasticity.

[14] In the method for adhering a protective film according to the fourth aspect of the present invention, when the average height of the bumps is H1 and the average thickness of the protective film is H2, the ratio H2 / H1 can be 0.5≦H2 / H1.

[15] A fifth aspect of the present invention relates to a method for manufacturing a semiconductor component, which method includes the method for attaching a protective film according to the fourth aspect of the present invention.

[16] The sixth aspect of the present invention relates to a protective film that is used in the fourth aspect of the present invention. [Effects of the Invention]

[0013] According to the protective film adhering methods of the first and fourth aspects of the present invention, when there are steps on the main surface of a semiconductor wafer due to the presence or absence of bumps, the protective film can be adhered so as to reduce or eliminate these steps, thereby making the surface of the protective film substantially flat and reducing defects caused by the steps on the main surface of the semiconductor wafer.

[0014] According to the semiconductor component manufacturing methods of the second and fifth aspects of the present invention, it is possible to suppress the occurrence of defects caused by steps on the main surface of a semiconductor wafer, thereby enabling efficient manufacturing of semiconductor components. The protective films of the third and sixth aspects of the present invention can suppress the occurrence of defects caused by unevenness on the main surface of a semiconductor wafer, thereby enabling efficient production of semiconductor components. [Brief explanation of the drawings]

[0015] [Figure 1] 1A is a plan view illustrating a semiconductor wafer to be subjected to the bonding method of the present invention, and FIG. 1B is an enlarged cross-sectional side view taken along the line 1B-1B in FIG. 1A. [Figure 2] FIG. 2 is an enlarged cross-sectional side view illustrating the protective film according to the present invention. [Figure 3] 1A and 1B are a plan view and an enlarged side cross-sectional view, respectively, illustrating a sticking device according to a sticking method of a first invention. [Figure 4] 1A and 1B are a plan view and an enlarged cross-sectional side view, respectively, illustrating a placement step according to the adhering method of the first invention. [Figure 5] FIG. 2 is an enlarged cross-sectional side view illustrating a bonding step according to the bonding method of the first invention. [Figure 6] FIG. 3 is an enlarged cross-sectional side view illustrating a compression step in the bonding method of the first invention. [Figure 7]1 is an enlarged cross-sectional side view illustrating a semiconductor wafer to which a protective film according to a bonding method of a first invention has been bonded. [Figure 8] FIG. 1 is an enlarged cross-sectional side view illustrating a semiconductor wafer to which a protective film has been attached according to a conventional attachment method. [Figure 9] FIG. 10 is an enlarged side cross-sectional view illustrating a modified example of the support member according to the adhering method of the first invention. [Figure 10] 1 is a graph illustrating the results of measuring the unevenness of the surface of a protective film in an example. [Figure 11] 11A and 11B are plan and enlarged cross-sectional views taken along the line 11B-11B in FIG. 11A, respectively, illustrating another example of a semiconductor wafer to be subjected to the bonding method of the present invention. [Figure 12] 1A and 1B are enlarged cross-sectional side views illustrating the relationship between a clearance C1 of a semiconductor wafer relative to a pressing member and a clearance C2 of a supporting member, according to a first aspect of the present invention. [Figure 13] 1A is an enlarged cross-sectional side view illustrating the positioning step of the adhering method of the first invention, and FIG. 1B is an enlarged cross-sectional side view illustrating the compression step of the adhering method of the first invention. [Figure 14] 10A and 10B are side cross-sectional views illustrating the processing steps of the adhering method of the fourth invention, and FIG. [Figure 15] FIG. 10 is an enlarged side cross-sectional view illustrating a placement step according to the adhering method of the fourth invention. [Figure 16] FIG. 10 is an enlarged cross-sectional side view illustrating a bonding step according to a bonding method of the fourth invention. [Figure 17] 10A and 10B are enlarged cross-sectional side views illustrating another example of the processing steps according to the adhering method of the fourth invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] The present invention will now be described with reference to the drawings. The matters set forth herein are intended to exemplify and exemplify embodiments of the present invention, and are set forth in order to provide what is believed to be the most effective and easily understandable explanation of the principles and conceptual features of the present invention. In this regard, it is not intended to show structural details of the present invention beyond the extent necessary for a fundamental understanding of the present invention, and the description, taken in conjunction with the drawings, will make clear to those skilled in the art how some aspects of the present invention can be actually embodied.

[0017] [1] Adhesion method (first embodiment) This adhering method is a first embodiment according to the first invention, and is a method for adhering a protective film 20 that protects a main surface 10A of a semiconductor wafer 10. This bonding method includes a placement step S1 (see FIG. 4(b)) of placing the protective film 20 so as to cover the main surface 10A of the semiconductor wafer 10, and a bonding step S2 (see FIG. 5) of pressing the protective film 20 against the main surface 10A to bond it. The main surface 10A of the semiconductor wafer 10 has a first region 12 where the bumps 11 are arranged, and a second region 13 which is a region including at least a part of the periphery of the main surface 10A and where the bumps 11 are not arranged (see Figures 1(a) and (b)). The attaching step S2 includes a compressing step S3 of compressing the protective film 20 in its thickness direction (see FIG. 6). This compressing step S3 is performed using a pressing member 32 for pressing the protective film 20 against the main surface 10A and a support member 33 installed along the outer periphery of the second region 13.

[0018] The semiconductor wafer 10 to which the protective film 20 has been attached using this attachment method is then back-grinded to the desired thickness, separated into individual pieces, and subjected to various processes to manufacture semiconductor components from the semiconductor wafer 10. That is, this bonding method (first embodiment) is included in the method for manufacturing a semiconductor component according to the second invention.

[0019] The semiconductor wafer 10 used in this bonding method has bumps 11 on either the front or back surface, and the entire surface of the semiconductor wafer 10 having the bumps 11 is designated as the main surface 10A (see FIG. 1(b)). This adhering method can be carried out using an adhering device 30 (see FIG. 3) that can perform the placing step S1, the adhering step S2, and the compressing step S3. The pressing member 32 and the support member 33 can be provided in the sticking device 30.

[0020] In this attachment method, the attachment step S2 includes a compression step S3 of compressing the protective film 20 in its thickness direction. This compression step S3 is performed using a pressing member 32 for pressing the protective film 20 against the main surface 10A and a support member 33 installed along the outer periphery of the second region 13 of the main surface 10A. In the compression step S3, the protective film 20 is compressed in the thickness direction, and the layer (irregularity absorption layer 23) that exhibits fluidity or plasticity flows appropriately in accordance with the steps and irregularities, causing the thickness to shift to fill in the steps and irregularities. Furthermore, when the compression step S3 is performed using the pressing member 32 and the support member 33, the flow of the thick portion of the protection film 20 that tends to move further outward than the periphery of the main surface 10A is restricted. Furthermore, by restricting the flow of the thick portion of the protective film 20 as described above, the thick portion of the protective film 20 (irregularity absorption layer 23) is biased thickly on the second region 13 of the main surface 10A, thereby filling in the steps on the main surface 10A and making the surface of the protective film 20 flat.

[0021] [2] Semiconductor wafers The semiconductor wafer 10 used in this bonding method is not particularly limited in terms of material or shape, but is usually formed into a disk shape using silicon as the material. As shown in FIGS. 1(a) and 1(b), this semiconductor wafer 10 has a plurality of bumps 11 on its main surface 10A. Here, the main surface 10A is the entire surface of the semiconductor wafer 10 on which the bumps 11 are provided. The main surface 10A includes the front surface of the semiconductor wafer 10 and the front surfaces of the bumps 11. In addition, the surface of the semiconductor wafer 10 opposite the main surface 10A is referred to as the back surface.

[0022] The main surface 10A has a first region 12 where the bumps 11 are arranged and a second region 13 where the bumps 11 are not arranged. Of these, the second region 13 has a peripheral region 13A and a blank region 13B. Of the above, peripheral region 13A is a region that forms the periphery of semiconductor wafer 10 (i.e., a region that forms the periphery of main surface 10A). Generally, semiconductor wafer 10 is provided with a chamfered portion 14 on the periphery to prevent chipping or cracking of the periphery (see FIGS. 1(b) and 11(b)), and the region that includes this chamfered portion 14 is peripheral region 13A. For this reason, no bumps are arranged in peripheral region 13A that includes chamfered portion 14. On the other hand, the blank area 13B is an area where bumps can be arranged but no bumps are actually arranged. Specifically, the blank area 13B is the area of ​​the second area 13 excluding the peripheral area 13A.

[0023] The shape (planar shape) of each of the above-mentioned regions is not limited, but for example, the first region 12 can be provided in a substantially circular shape in a planar view at approximately the center of the main surface 10A, as exemplified in Fig. 1(a). Also, the first region 12 can be provided in a substantially polygonal shape in a planar view at approximately the center of the main surface 10A, as exemplified in Fig. 11(a). In order to make the first region 12 and the second region 13 easier to understand, the boundary between these regions is shown by a two-dot chain line in FIG. 1(a) and FIG. 11(a).

[0024] Furthermore, the second region 13 can be provided in a shape that surrounds the first region 12, as exemplified in, for example, FIGS. 1(a) and 11(a). Furthermore, the shape of the peripheral region 13A constituting the second region 13 can be, for example, a substantially circular ring shape in plan view so as to surround the first region 12 inside (see FIGS. 1 and 11).

[0025] The shape (planar shape) of the blank area 13B can be arched, as shown in FIG. 1(a). That is, the blank area 13B can be formed by extending the peripheral area 13A in an arch shape toward the center of the main surface 10A on the left side of the main surface 10A. Such a blank area 13B can be used to display (e.g., engrave) various information such as the serial number or manufacturing number of the semiconductor wafer 10. Therefore, the arched blank area 13B in FIG. 1(a) can also be called an identification area. 11(a), the shape (planar shape) of the blank region 13B can be a shape that surrounds the periphery of the first region 12 on all four sides (front, back, left, and right). More specifically, the shape of the blank region 13B can be a shape in which four arc shapes are connected together. Such a blank region 13B can be used as a region in which bumps 11 are not arranged, for example, because errors are likely to occur during product manufacturing. Furthermore, the blank area 13B in FIG. 11(a) can also be said to be an area formed when the size of the chip cut out from the semiconductor wafer 10 is large. That is, when the size of the chip is small, the first area 12 has a substantially circular shape in the plan view of FIG. 11(a). On the other hand, when the size of the chip is large, the first area 12 has a substantially polygonal shape in the plan view of FIG. 11(a). Then, when the first area 12 has a substantially polygonal shape in the plan view, the blank area 13B in FIG. 11(a) is formed so as to surround the periphery of this first area 12. When the blank area 13B in FIG. 11(a) is formed, the size of the chip is, for example, 100 mm. 2 That's all. In the following description, the surface of the blank area 13B will be referred to as "blank area surface 101A."

[0026] The average height H1 of the bumps 11 on the main surface 10A is not particularly limited and can be set arbitrarily depending on the type of bumps 11, such as plated bumps, ball bumps, printed bumps, etc. Generally, the average height H1 of the bumps 11 on the main surface 10A is preferably less than 350 μm, more preferably in the range of 5 to 250 μm, and even more preferably in the range of 10 to 150 μm. The ratio of the area of ​​the second region 13 to the total area of ​​the main surface 10A is not particularly limited and can be set arbitrarily depending on the size of the blank region 13B, but is preferably less than 30%, more preferably 23% or less, and even more preferably 15% or less. The ratio of the area of ​​peripheral region 13A to the total area of ​​main surface 10A is not particularly limited, but is preferably 10% or less, more preferably 8% or less, and even more preferably 5% or less. The ratio of the area of ​​blank region 13B to the total area of ​​main surface 10A is not particularly limited and can be set arbitrarily, but is preferably 20% or less, more preferably 15% or less, and even more preferably 10% or less.

[0027] In the second region 13, both the peripheral region 13A and the blank region 13B have a step between them and the first region 12, and depressions or dents that mimic this step are formed on the surface of the protective film 20, which may cause problems such as vacuum errors, cracks, or breakage. When comparing peripheral region 13A and blank region 13B, blank region 13B has a larger area ratio to the total area of ​​main surface 10A than peripheral region 13A, so larger dents, depressions, etc. are more likely to form on the surface of protective film 20 than in peripheral region 13A, which is likely to cause the above-mentioned defects. Therefore, in the following description, the second region 13 will be described as the blank region 13B unless otherwise specified.

[0028] [3] Protective film The protective film 20 used in this adhesion method is a film used in the manufacturing method of semiconductor components, more specifically, a film used in the back-grinding process in the manufacturing method of semiconductor components to reduce the semiconductor wafer to the desired thickness. That is, the protective film is a protective film according to the third aspect of the present invention.

[0029] As shown in FIG. 2, the protective film 20 can have a configuration including a base layer 21 and an adhesive layer 22. The protective film 20 preferably has a layer capable of exhibiting fluidity or plasticity from the viewpoint of eliminating unevenness caused by the bumps 11 and steps caused by the height difference between the first region 12 and the second region 13. The protective film 20 of this embodiment has an unevenness absorbing layer 23 between the base layer 21 and the adhesive layer 22 as a layer capable of exhibiting fluidity or plasticity.

[0030] From the viewpoint of suitably eliminating the unevenness caused by the bumps 11 and the steps caused by the difference in height between the first region 12 and the second region 13, it is preferable that the average thickness H2 of the protective film 20 satisfies the relational expression 0.5≦H2 / H1 with the average height H1 of the bumps 11. The upper limit of H2 / H1 is not particularly limited, as long as the thickness of the protective film 20 is sufficient to absorb and suitably eliminate the unevenness caused by the bumps 11 and the steps caused by the difference in height between the first region 12 and the second region 13. From the viewpoint of suppressing material loss due to an increase in the average thickness H2 of the protective film 20 and further suitably maintaining the formability of the protective film 20, H2 / H1 is usually 10 or less (H2 / H1≦10), preferably 5 or less (H2 / H1≦5), and more preferably 4 or less (H2 / H1≦4).

[0031] Specifically, the average thickness H2 of the protective film 20 is preferably 30 μm or more, more preferably 100 μm or more, and even more preferably 200 μm or more. The average height H1 is the average of the measured heights of 1 / 10 of the total number of bumps selected randomly, and the average thickness H2 is the average of the measured thicknesses of 10 locations on the film selected at least 2 cm apart.

[0032] Each layer of the protective film will be described below. (1) Base layer The base layer 21 is a layer provided for the purpose of improving the properties of the protective film 20, such as ease of handling, mechanical properties, and heat resistance. The material used for the base layer 21 is not particularly limited as long as it has a mechanical strength that can withstand the external force applied when polishing the semiconductor wafer in the back-grinding process. Generally, the base layer 21 is made of a synthetic resin film.

[0033] Examples of the synthetic resins mentioned above include one or more thermoplastic resins selected from polyolefins such as polyethylene, polypropylene, poly(4-methyl-1-pentene), and poly(1-butene); polyesters such as polyethylene terephthalate and polybutylene terephthalate; polyamides such as nylon-6, nylon-66, and polymetaxylene adipamide; polyacrylate; polymethacrylate; polyvinyl chloride; polyetherimide; ethylene-vinyl acetate copolymer; polyacrylonitrile; polycarbonate; polystyrene; ionomer; polysulfone; polyethersulfone; and polyphenylene ether. Among these synthetic resins, from the viewpoint of adequately protecting the semiconductor wafer in the back-grinding step, one or more types selected from polypropylene, polyethylene terephthalate, polyamide, and ethylene-vinyl acetate copolymer are preferred, and one or more types selected from polyethylene terephthalate and ethylene-vinyl acetate copolymer are more preferred. Furthermore, additives that can be added to the synthetic resin include plasticizers, softeners (mineral oil, etc.), fillers (carbonates, sulfates, titanates, silicates, oxides (titanium oxide, magnesium oxide), silica, talc, mica, clay, fibrous fillers, etc.), antioxidants, light stabilizers, antistatic agents, lubricants, colorants, etc. These additives may be used alone or in combination of two or more.

[0034] The above-mentioned film may be either unstretched or stretched, such as a uniaxially stretched film or a biaxially stretched film, but from the viewpoint of improving mechanical strength, a stretched film is preferred. The film may be either a single layer film or a multilayer film having a plurality of layers.

[0035] It is preferable to use a surface-treated film for the base layer 21 from the viewpoint of improving adhesion with the irregularity absorbing layer 23, etc. Specific examples of surface treatments include corona treatment, plasma treatment, undercoat treatment, and primer coat treatment. The thickness of the base layer 21 is not particularly limited, but from the viewpoint of obtaining good characteristics, it is preferably 10 to 200 μm, more preferably 20 to 150 μm, and even more preferably 30 to 100 μm.

[0036] (2) Adhesive layer The adhesive layer 22 is a layer provided for the purpose of adhering and fixing the protective film 20 to the main surface 10A of the semiconductor wafer 10. The material of the adhesive layer 22 is not particularly limited, but a material containing at least a main adhesive agent is used. Examples of the main adhesive agent include a (meth)acrylic adhesive, a silicone adhesive, a urethane adhesive, and a rubber adhesive. The material of the adhesive layer 22 may contain a crosslinking agent in addition to the main adhesive agent.

[0037] Both an energy ray-curable adhesive material that can be cured by energy rays and a non-energy ray-curable adhesive material that cannot be cured by energy rays can be used as the material for the adhesive layer 22. Among these, an energy ray-curable adhesive material is preferred as the material for the adhesive layer 22 from the viewpoint that the adhesive material is cured by energy ray irradiation to reduce its adhesive strength, thereby enabling the protective film 20 to be peeled off from the main surface 10A without leaving any adhesive residue. Regarding the energy ray-curable adhesive material, the type of energy ray is not particularly limited, and examples thereof include ultraviolet rays, electron beams, and infrared rays. The energy ray-curable adhesive material may contain, in addition to the adhesive main agent, a compound having a carbon-carbon double bond in the molecule and a photopolymerization initiator that can initiate polymerization of the curable compound in response to energy rays. The curable compound is preferably a monomer, oligomer, or polymer that has a carbon-carbon double bond in the molecule and is curable by radical polymerization.

[0038] The adhesive strength of adhesive layer 22 is not particularly limited, but from the viewpoint of ensuring good adhesion to the semiconductor wafer while suppressing adhesive residue on the semiconductor wafer when peeled off, the adhesive strength to the silicon wafer when peeled off after being attached to the surface of the silicon wafer and left for 60 minutes, as measured in accordance with JIS Z0237 (measured in an environment of a temperature of 23°C and a relative humidity of 50%) is preferably 0.1 to 10 N / 25 mm. The adhesive strength is more preferably 0.2 to 9 N / 25 mm, and even more preferably 0.3 to 8 N / 25 mm. The thickness of the adhesive layer 22 is not particularly limited, but is preferably 1 to 50 μm, more preferably 2 to 45 μm, and even more preferably 3 to 40 μm, from the viewpoint of exhibiting suitable adhesive strength while being peelable without leaving any adhesive residue.

[0039] (3) Uneven absorption layer The unevenness absorption layer 23 is a layer that is provided for the purpose of smoothing the surface of the protective film 20 by absorbing the uneven shape caused by the bumps 11 arranged on the main surface 10A and filling in the steps caused by the difference in height between the first region 12 and the second region 13, using the unevenness absorption properties achieved by the expression of fluidity or plasticity. The material of the irregularity absorbing layer 23 is not particularly limited as long as it has the ability to absorb irregularities due to the manifestation of fluidity or plasticity, but thermoplastic resins are usually used.

[0040] Specific examples of thermoplastic resins include olefin resins, ethylene-polar monomer copolymers, ABS resins, vinyl chloride resins, vinylidene chloride resins, (meth)acrylic resins, polyamide resins, fluorine-based resins, polycarbonate resins, polyester resins, etc. Among these, at least one selected from olefin resins and ethylene-polar monomer copolymers is preferred from the viewpoint of good roughness absorbency.

[0041] Examples of olefin-based resins include linear low-density polyethylene (LLDPE), low-density polyethylene, high-density polyethylene, polypropylene, ethylene-α-olefin copolymers containing ethylene and an α-olefin having 3 to 12 carbon atoms, propylene-α-olefin copolymers containing propylene and an α-olefin having 4 to 12 carbon atoms, ethylene-cyclic olefin copolymers, and ethylene-α-olefin-cyclic olefin copolymers.

[0042] Examples of ethylene-polar monomer copolymers include ethylene-unsaturated carboxylic acid ester copolymers such as ethylene-ethyl (meth)acrylate copolymer, ethylene-methyl (meth)acrylate copolymer, ethylene-propyl (meth)acrylate copolymer, and ethylene-butyl (meth)acrylate copolymer; and ethylene-vinyl ester copolymers such as ethylene-vinyl acetate copolymer, ethylene-vinyl propionate copolymer, ethylene-vinyl butyrate copolymer, and ethylene-vinyl stearate copolymer. The above-mentioned thermoplastic resins may be used alone or in combination of two or more.

[0043] The density of the irregularity absorbing layer 23 is not particularly limited, but from the viewpoint of the balance (rigidity-flexibility) between flexibility related to irregularity absorption and rigidity related to durability in the back grinding process, it is preferably 800 to 990 kg / m 3 , more preferably 830 to 980 kg / m 3 , and more preferably 850 to 970 kg / m 3 is. The thickness of the irregularity absorption layer 23 is not particularly limited as long as it is a thickness that can exhibit irregularity absorption properties for the irregular shape caused by the bump 11 and the steps caused by the height difference between the first region 12 and the second region 13, but from the viewpoint of being able to suitably exhibit irregularity absorption properties, it is preferably 20 μm or more, more preferably 80 μm or more, and even more preferably 170 μm or more.

[0044] The storage modulus G'(60) of the irregularity absorbing layer 23 at 60°C is set to 0.05 × 10 from the viewpoint that the irregularity absorbing layer 23 can exhibit suitable irregularity absorbing properties by heating when the protective film 20 is attached. 6 ~1.0×10 6 Pa is preferred, and 0.075×10 6 ~0.5×10 6 It is Pa. The storage modulus G'(25) of the irregularity absorbing layer 23 at 25°C is set to 4.0 × 10 from the viewpoint that the irregularity absorbing layer 23 can maintain its shape and maintain suitable adhesion to the main surface 10A after the protective film 20 is attached. 6 ~7.0×10 6 Pa is preferred, and 4.5×10 6 ~6.5×10 6 It is Pa.

[0045] The elastic modulus ratio G'(60) / G'(25) of the storage elastic modulus G'(25) to the storage elastic modulus G'(60) of the unevenness absorption layer 23 is preferably G'(60) / G'(25)<0.1, more preferably G'(60) / G'(25)≦0.08, and even more preferably G'(60) / G'(25)≦0.05, from the viewpoint of being able to exhibit good unevenness absorption properties while maintaining good adhesion to the main surface 10A. The storage modulus G' is measured using a dynamic viscoelasticity measuring device (e.g., Rheometrics, model "RMS-800") at a measurement frequency of 1 Hz and a strain of 0.1 to 3%, with G'(25) measured at 25°C and G'(60) measured at 60°C.

[0046] (4) Other demographics The protective film 20 is not limited to the configuration having the above-mentioned base layer 21, adhesive layer 22, and irregularity absorbing layer 23, but can also be configured to have other layers between the base layer 21 and the irregularity absorbing layer 23, or between the irregularity absorbing layer 23 and the adhesive layer 22. Examples of other layers include an interface strength improving layer that improves the interface strength with the adhesive layer 22, a migration prevention layer that suppresses migration of low molecular weight components to the adhesive surface of the adhesive layer 22, and an antistatic layer that prevents static buildup on the protective film 20. These may be used alone or in combination of two or more.

[0047] [4] Pasting device The adhering device 30 is not particularly limited as long as it is configured to be able to perform the arranging step S1, the adhering step S2, and the compressing step S3. The bonding device 30 may have the following configuration, for example. As shown in Figures 3(a) and (b), the bonding device 30 has a chuck table 31, a pressing member 32 arranged above the chuck table 31, and a support member 33 arranged next to the chuck table 31. The chuck table 31 is used to support and fix the semiconductor wafer 10 placed on its surface. The pressing member 32 is for pressing the protective film 20 against the main surface 10 A of the semiconductor wafer 10 supported and fixed on the chuck table 31 . The support member 33 is installed along the outer periphery of the second region 13 of the semiconductor wafer 10 supported and fixed on the chuck table 31 , and serves to support the edge of the protective film 20 .

[0048] The bonding device 30 may be configured to have a heating mechanism for heating the protective film 20, from the viewpoint of suitably imparting fluidity or plasticity to the irregularity absorbing layer 23 of the protective film 20. An example of this heating mechanism is a hot air heater. From the viewpoint of being able to suitably perform the arrangement step S1, the bonding device 30 may be configured to have a supply mechanism that supplies the protective film 20 into the device. Examples of this supply mechanism include a film supply roller, a film supply arm, etc.

[0049] Each of the components of the adhering device will be described below. (1) Chuck table The chuck table 31 is not particularly limited in type, configuration, etc., as long as it can support and fix the semiconductor wafer 10 . The chuck table 31 is preferably a vacuum suction table, from the viewpoint of being able to suitably fix the semiconductor wafer 10 and preventing the semiconductor wafer 10 from being soiled or scratched.

[0050] (2) Pressing member The pressing member 32 is not particularly limited in shape, configuration, etc., as long as it can press the protective film 20 against the main surface 10A of the semiconductor wafer 10. The pressing member 32 shown in Figures 3(a) and (b) is formed in a disk shape and is arranged above the semiconductor wafer 10 supported and fixed on the chuck table 31, and is configured to be able to move towards or away from the semiconductor wafer 10.

[0051] From the viewpoint of flattening the surface of the protective film 20 attached to the main surface 10A of the semiconductor wafer 10, it is preferable that the pressing surface 32A of the pressing member 32 that presses the protective film 20 is a flat surface. The hardness of the pressing surface 32A is preferably 2.5 to 8.5, more preferably 3 to 7, and even more preferably 4 to 6 on the Mohs scale, from the viewpoint of suppressing deformation when the protective film 20 is pressed and maintaining the pressing surface 32A as a flat surface. The material of the pressing surface 32A is not particularly limited, but from the viewpoint of satisfying the above Mohs hardness, metals such as iron, copper, aluminum, steel, stainless steel, and aluminum alloys, and inorganic materials such as glass and ceramics can be used. The pressing member 32 may be configured such that, for example, only the pressing surface 32A is made of the inorganic material, and the portions other than the pressing surface 32A are made of synthetic resin.

[0052] The configuration for moving the pressing member 32 toward or away from the semiconductor wafer 10 is not particularly limited. For example, the pressing member 32 may be configured such that one edge thereof is rotatably attached to the bonding device 30, and that it approaches the semiconductor wafer 10 when it is flipped down, and moves away from the semiconductor wafer 10 when it is flipped up. In addition, the pressing member 32 can be attached to a rail or the like provided on the bonding device 30 so as to be able to move up and down freely and extend in the thickness direction of the semiconductor wafer 10, and can be configured so that when it moves down it approaches the semiconductor wafer 10 and when it moves up it moves away from the semiconductor wafer 10. In addition, the pressing member 32 is fixed at a position above the chuck table 31, and the chuck table 31 can be configured to be freely raised and lowered, so that when the chuck table 31 is raised, the semiconductor wafer 10 approaches the pressing member 32, and when the chuck table 31 is lowered, the semiconductor wafer 10 moves away from the pressing member 32.

[0053] (3) Support member The support member 33 is not particularly limited in terms of its configuration, etc., as long as it can compress the protective film 20 in the compression step S3. The shape of the support member 33 is not particularly limited as long as it can be placed along the outer periphery of the second region 13 of the semiconductor wafer 10 and can perform the compression step S3 favorably. Examples of such a shape include a circular ring, a fan shape, an arc shape, etc. in a plan view. The material of the support member 33 is not particularly limited as long as it can sandwich and compress the protective film 20 together with the pressing member 32. Examples of such materials include inorganic materials such as metals listed as examples of the pressing member 32, as well as thermoplastic resins such as engineering plastics and super engineering plastics, and thermosetting resins.

[0054] The support member 33 shown in FIGS. 3(a) and 3(b) is formed in a circular ring shape in a plan view so that the entire semiconductor wafer 10 can be enclosed therein. When the support member 33 has a fan-like or arc-like shape in plan view, it is preferable to place the support member 33 along the outer periphery of the second region 13, particularly the blank region 13B.

[0055] As shown in Figure 6, the support member 33 requires a width W1 of at least a certain amount when viewed in a plane, which allows the protective film 20 to exert its effect, i.e., to fill in the step in the blank area 13B in the portion sandwiched between the pressing member 32 and the support member 33. The volume required to fill the step is adjusted appropriately depending on conditions such as the height of the bumps 11, the area of ​​the blank regions 13B on the main surface 10A of the semiconductor wafer 10, the thickness of the protective film 20, and the like. Therefore, the width W1 of the support member 33 in a planar view is not particularly limited, but from the viewpoint of being able to reliably sandwich and compress the protective film 20 between the support member 33 and the pressing member 32, it is generally preferably 1 to 20 mm, more preferably 2 to 15 mm, and even more preferably 3 to 10 mm.

[0056] In the support member 33, the support surface 33A that supports the edge of the protective film 20 is parallel to the main surface 10A of the semiconductor wafer 10 from the viewpoint of preferably moving the edge thickness of the protective film 20 (for example, the uneven absorption layer 23) compressed in the compression step S3 to the second region 13 of the main surface 10A of the semiconductor wafer 10, particularly onto the blank region surface 101A of the blank region 13B. Alternatively, as shown in FIG. 9, the support surface 33A of the support member 33 may be inclined so as to face the main surface 10A side of the semiconductor wafer 10 from the viewpoint of more preferably moving the edge thickness of the protective film 20 (for example, the uneven absorption layer 23) compressed in the compression step S3 onto the blank region surface 101A.

[0057] In the sticking device 30 shown in FIGS. 3(a) and (b), when the clearance between the main surface 10A of the semiconductor wafer 10 and the pressing member 32 is C1 and the clearance between the support member 33 and the pressing member 32 is C2, C1 > C2 from the viewpoint of preferably performing the compression step S3. In the case of C1 > C2, the support surface 33A of the support member 33 is arranged at a position higher than the blank region surface 101A on the main surface 10A of the semiconductor wafer 10. Note that the above clearances C1 and C2 can also be set to C1 = C2 or C 1 < C2. In the case of C1 = C2, the support surface 33A of the support member 33 is arranged at the same height as the surface of the second region 13 of the semiconductor wafer 10. In the case of C1 < C2, the support surface 33A of the support member 33 is arranged at a position lower than the surface of the second region 13 of the semiconductor wafer 10.

[0058] More specifically, in the case where the position of the blank region surface 101A in the thickness direction of the semiconductor wafer 10 is P1, the position of the support surface 33A of the support member 33 is P2, and the distance between these P1 and P2 is d1 (μm), when C1 and C2 satisfy C1 > C 2 (see FIG. 12(a)), it is preferable that 50 ≤ d1 (μm) ≤ 2000, and more preferably 100 ≤ d1 (μm) ≤ 1000. Similarly, when the position of the surface 101A of the blank region in the thickness direction of the semiconductor wafer 10 is P1, the position of the support surface 33A of the support member 33 is P2, and the distance between P1 and P2 is d2 (μm), when C1 and C2 satisfy C1 < C2 (see Fig. 12(b)), it is preferable that 0 < d2 (μm) < 400, more preferably 10 ≦ d2 (μm) ≦ 300, and even more preferably 50 ≦ d2 (μm) ≦ 200.

[0059] [5] Placement step As shown in Figs. 4(a) and (b), the placement step S1 is a step of separating the pressing member 32 (not shown) from the semiconductor wafer 10 and supplying the protective film 20 onto the main surface 10A of the semiconductor wafer 10. In this placement step S1, the supplied protective film 20 is arranged to cover the main surface 10A of the semiconductor wafer 10 (see Figs. 4(b) and 5).

[0060] The shape of the protective film 20 to be supplied is not particularly limited, and any of circular, square, rectangular, or strip-shaped in plan view can be used. The supply method of the protective film 20 is not particularly limited, and either a batch method of supplying the protective film 20 one by one or a continuous method of continuously supplying the protective film 20 can be used. In the placement step S1 shown in Figs. 4(a) and (b), the shape of the protective film 20 to be supplied is circular in plan view corresponding to the main surface 10A, and the supply method of the protective film 20 is the batch method.

[0061] In the placement step S1, from the two viewpoints of ensuring a sufficient amount of film to sufficiently fill the step across the entire second region 13 and preferably restricting the flow of the film portion further outside the periphery of the main surface 10A, the edge (peripheral edge) of the protective film 20 is arranged so as to protrude outside the periphery of the second region 13. There is no particular limitation on the amount of overhang of the edge of the protective film 20. From the viewpoint of reliably performing the compression step S3, it is preferable that the overhang amount be an amount that allows the overhanging edge to rest on the support surface 33A of the support member 33.

[0062] As shown in Figure 6, in order to exert the effect of the protective film 20, i.e., the effect of filling in the step of the blank area 13B in the portion sandwiched between the pressing member 32 and the support member 33, it is preferable that the amount of overhang of the edge of the protective film 20 be set to a certain width W2 or more when viewed in a plane, and that the protective film 20 be placed on the support surface 33A of the support member 33. The volume required to fill the step is adjusted appropriately depending on conditions such as the height of the bumps 11, the area of ​​the blank regions 13B on the main surface 10A of the semiconductor wafer 10, the thickness of the protective film 20, and the like. Therefore, the width W2 in a planar view of the amount of overhang of the edge of the protective film 20 is not particularly limited, but from the standpoint of reducing the amount of protective film 20 that is discarded as excess, it is generally more preferable that the amount not extend further out than the periphery of the support surface 33A. Specifically, when the length between the position on the protective film 20 corresponding to the peripheral edge of the main surface 10A and the outer peripheral edge of the protective film 20 is defined as the width W2 in the plan view, the amount of overhang of the edge of the protective film 20 is preferably 0.5 to 10 mm, more preferably 1 to 8 mm, and even more preferably 1.5 to 6 mm.

[0063] [6] Pasting process As shown in FIG. 5, the adhering step S2 is a step of bringing a pressing member 32 close to the main surface 10A of the semiconductor wafer 10 and pressing the protective film 20 against the main surface 10A with the pressing member 32 to adhere it. The attaching step S2 includes a compressing step S3 of compressing the protective film 20 in its thickness direction. The timing of execution of the compression step S3 in the adhesion step S2 is not particularly limited, and for example, the compression step S3 can start after the adhesion step S2 starts, the compression step S3 and the adhesion step S2 can end at approximately the same time, or the compression step S3 can end before the adhesion step S2 ends.

[0064] Furthermore, in the adhering step S2, the protective film 20 is heated using the heating mechanism of the adhering device 30, so that the thick portion of the protective film 20 (irregularity absorbing layer 23) can be suitably deformed in the compressing step S3. The heating temperature of the protective film 20 is not particularly limited as long as it is set to a temperature at which the irregularity absorbing layer 23 can be suitably deformed in accordance with the storage elastic modulus G′ of the irregularity absorbing layer 23 described above. Specifically, the heating temperature of the protective film 20 is preferably 50 to 200°C, more preferably 60 to 100°C, and even more preferably 70 to 90°C, provided that the storage modulus G' of the irregularity absorbing layer 23 is within the above-mentioned range.

[0065] (1) Compression process In the compression step S3, as shown in FIG. 6, the edge portion of the protective film 20 is supported by a support member 33, and the edge portion is compressed by being sandwiched between the support member 33 and a pressing member 32. The compression force when compressing the edge portion of the protective film 20 can be set by the pressure applied by the pressing member 32. The specific pressure is preferably 0.3 to 2 MPa, more preferably 0.4 to 1.5 MPa, and even more preferably 0.5 to 1 MPa, from the viewpoint of being able to suitably compress the edge portion of the protective film 20 and preventing the occurrence of cracks in the semiconductor wafer 10.

[0066] In the compression process S3, on the first region 12 of the main surface 10A, the thick portion (irregularity absorption layer 23) of the protective film 20 that is sandwiched between the pressing member 32 and the bump 11 and crushed in the thickness direction deforms to conform to the irregularities of the bump 11 and fill in these irregularities. Then, a portion of the thick portion of the protective film 20 that has been crushed in the thickness direction flows onto the blank area 13B of the second area 13, as shown by the arrow on the right side in Figure 6, increasing the amount of thick portion of the protective film 20 on the blank area surface 101A.

[0067] On the other hand, the edge of the protective film 20, which is sandwiched between the support member 33 and the pressing member 32 and compressed in the thickness direction, is caused to flow so that the flesh portion (irregularity absorption layer 23) is squeezed out onto the blank area surface 101A, as shown by the arrow on the left in Figure 6, thereby increasing the amount of flesh of the protective film 20 on the blank area surface 101A. In addition, the edge of the protective film 20 compressed in the thickness direction prevents the flesh from escaping further outward from the periphery of the second region 13 by the support member 33 and the pressing member 32 restricting the flow of the flesh from above the blank region surface 101A.

[0068] Therefore, the protective film 20 on the blank area surface 101A is filled with material from the first area 12 and the compressed edges, so that the protective film 20 is filled with a sufficient amount of material to fill in the steps throughout the second area 13. In this way, the protective film 20 on the blank area surface 101A that has been filled with material increases in thickness, thereby filling in the steps throughout the second area 13. Furthermore, since the surface of the protective film 20 is pressed by the pressing member 32, it is not affected by the flow of the flesh portion and is made flat in accordance with the pressing surface 32A.

[0069] After the compression step S3, the semiconductor wafer 10 with the protective film 20 attached to the main surface 10A is removed from the attachment device 30, and excess portions such as the edges of the compressed protective film 20 are cut off. In the semiconductor wafer 10 from which the excess portion has been cut off, as shown in FIG. 7, the thick portion of the protective film 20 is biased thickly onto the blank area surface 101A, thereby filling in the step. In addition, in the above description, the blank area 13B is used as the second area 13, but similarly to this blank area 13B, in the peripheral area 13A, the thickness of the protective film 20 is biased toward the second area 13, thereby filling in the step. The surface of the protective film 20 attached to the semiconductor wafer 10 is then free of defects following the steps of the semiconductor wafer 10, and becomes a uniformly flat surface overall.

[0070] The above-mentioned attachment method has been explained using the example of blank area 13B, which is mainly used as an identification area as shown in Figures 1(a) and (b), but the same effect can be obtained with blank area 13B as shown in Figures 11(a) and (b). That is, this bonding method is particularly useful when the target semiconductor wafer 10 has a blank area 13B having a flat blank area surface 101A in the second area 13, which is an area where no bumps are arranged.

[0071] [7] Adhesion method (second embodiment) This adhesion method is a second embodiment according to the first invention. Like the first embodiment, this bonding method (second embodiment) is included in the method for manufacturing a semiconductor component according to the second invention. The semiconductor wafer 10 and the protective film 20 used in this bonding method are as described above in [2] Semiconductor wafer and [3] Protective film, and therefore further description will be omitted.

[0072] The adhering method of the second embodiment differs from the first embodiment in the arrangement step and compression step, which will be described below. (1) Placement process 13(a), the above-mentioned arrangement step S1 can be a step of arranging the protective film 20 so that the edge (periphery) of the protective film 20 is located more inward than the support member 33. In this arrangement step S1, the edge of the protective film 20 is not placed on the support surface 33A of the support member 33. In this placement process S1, it is desirable to make the distance in a plan view between the edge of the protective film 20 and the inner surface of the support member 33 as short as possible, in order to prevent the second region 13 of the protective film 20 from expanding outward in the outer circumferential direction, which occurs in the compression process S3 described below, with the inner surface of the support member 33. Specifically, the distance in plan view between the edge of the protective film 20 and the inner circumferential surface of the support member 33 is preferably less than 1 mm, more preferably 0.5 mm or less, and even more preferably 0.3 mm or less. Most preferably, the distance in plan view between the edge of the protective film 20 and the inner circumferential surface of the support member 33 is 0 mm, that is, the edge of the protective film 20 is in contact with the inner circumferential surface of the support member 33.

[0073] (2) Compression process In the compression step S3 after the above-mentioned arrangement step S1, the protective film 20 sandwiched between the pressing member 32 and the main surface 10A attempts to bulge the fleshy portion (irregularity absorption layer 23) from its edge (peripheral edge) toward the outer periphery of the second region 13. This bulging of the fleshy portion (irregularity absorption layer 23) is blocked by the inner circumferential surface of the support member 33, as indicated by the arrow on the left side in Figure 13(b). The edge of the protective film 20 has a portion (irregularity absorption layer 23) blocked by the inner surface of the support member 33 that remains on the blank area surface 101A, and the portion flows from the first area 12 onto the blank area surface 101A, thereby providing a sufficient amount of material to fill in the steps throughout the entire second area 13. The edge of the protective film 20 on the blank area surface 101A is thickened by the increased thickness. Therefore, the compression step S3 is a step in which the edge of the protective film 20 is compressed by the pressing surface 32A of the pressing member 32, the inner circumferential surface of the support member 33, and the main surface 10A of the semiconductor wafer 10. Then, the edge of the compressed protective film 20 fills in the steps throughout the second area 13.

[0074] The semiconductor wafer 10 to which the protective film 20 has been attached by this attachment method is then back-grinded to a desired thickness, divided into individual pieces, and subjected to various processes to manufacture semiconductor components from the semiconductor wafer 10. In other words, this attachment method is included in the method for manufacturing semiconductor components.

[0075] When comparing the first and second embodiments of the attachment method of the present application, there is a difference in that in the first embodiment, the edge of the protective film 20 is compressed and crushed between the support member 33 and the pressing member 32, whereas in the second embodiment, the edge of the protective film 20 is not compressed between the support member 33 and the pressing member 32, but the inner peripheral surface of the support member 33 prevents the protective film 20 from expanding. The effect of this difference can be more pronounced when the protective film 20 has a layer that can exhibit fluidity or plasticity, i.e., the irregularity absorbing layer 23.

[0076] That is, when the protective film 20 has a layer (irregularity absorbing layer 23) that can exhibit fluidity or plasticity, and the adhering method of the first embodiment is carried out, the layer (irregularity absorbing layer 23) that constitutes the edge is made to flow and extruded into the second region 13 of the main surface 10A, and the amount of material can be replenished using not only the amount extruded from the first region 12 but also the amount extruded from the outer edge of the second region 13. In other words, the adhering method of the first embodiment fills in the step by extruding the irregularity absorbing layer 23 of the protective film 20 into the second region 13 from both the inner peripheral edge and the outer peripheral edge of the periphery surrounding the second region 13.

[0077] In contrast, when the protective film 20 has a layer (irregularity absorbing layer 23) that can exhibit fluidity or plasticity and the adhering method of the second embodiment is carried out, the layer (irregularity absorbing layer 23) that constitutes the edge cannot be caused to flow and extruded into the second region 13 of the main surface 10A, and it is necessary to replenish the amount of material only with the amount extruded from the first region 12. In other words, the adhering method of the second embodiment fills in the step by extruding the irregularity absorbing layer 23 of the protective film 20 into the second region 13 only from the inner peripheral edge of the peripheral edge surrounding the second region 13.

[0078] Therefore, when the protective film 20 has a layer (irregularity absorption layer 23) that can exhibit fluidity or plasticity, the first embodiment can also accommodate semiconductor wafers 10 that have larger blank areas 13B, and is therefore more advantageous than the second embodiment in that the layer (irregularity absorption layer 23) that forms the edge outside the second area 13 can be used to fill in the steps in the second area 13.

[0079] [8] Adhesion method (third embodiment) This adhesion method is a third embodiment according to the fourth aspect of the present invention. The semiconductor wafer 10 used in this bonding method (third embodiment) is the same as that used in the bonding methods of each of the above-mentioned embodiments, and its details are as described above in [2] Semiconductor wafer, so explanation will be omitted. The protective film 20 used in this attachment method (third embodiment) is the same as that used in the attachment methods of the above-mentioned embodiments, and details thereof are as described in [3] Protective film above, so description thereof will be omitted. In other words, the protective film 20 is also the protective film according to the sixth aspect of the present invention.

[0080] This bonding method (third embodiment) includes a processing step S11 (see Figures 14(a) and (b)) of processing the protective film 20 to obtain a processed film 20A, a placement step S12 (see Figure 15) of arranging the processed film 20A so as to cover the main surface 10A of the semiconductor wafer 10, and a bonding step S13 (see Figure 16) of pressing the processed film 20A against the main surface 10A to bond it. The processing step S11 is a step of forming portions of different thicknesses in the protective film 20 to obtain a processed film 20A. The arrangement step S12 is a step of arranging the relatively thick region 201 of the processed film 20A in correspondence with the second region 13, among the portions of the processed film 20A having different thicknesses.

[0081] The semiconductor wafer 10 to which the protective film 20 has been attached using this attachment method is then back-grinded to the desired thickness, separated into individual pieces, and subjected to various processes to manufacture semiconductor components from the semiconductor wafer 10. That is, this bonding method (third embodiment) is included in the method for manufacturing a semiconductor component according to the fifth aspect of the present invention.

[0082] In this bonding method, the processing step S11 can be performed using a processing device 40 (see FIGS. 14(a) and (b)) that can perform this step. In the processing step S11, the protective film 20 is processed to form areas of different thickness by causing the fleshy portion to shift to one side using a layer that exhibits fluidity or plasticity (irregularity absorption layer 23), resulting in a processed film 20A.

[0083] In this adhering method, the placing step S12 and the adhering step S13 can be performed using an adhering device 30 (see FIGS. 15 and 16) that can perform these steps. In the arrangement step S12, the processed film 20A is arranged on the main surface 10A so that the relatively thick region 201 of the portions having different thicknesses is positioned on the blank region surface 101A. In the bonding process S13, the processed film 20A is pressed against the main surface 10A by the pressing member 32, and the thick portion (irregularity absorption layer 23) is biased toward the relatively thick region 201 arranged on the blank area surface 101A of the main surface 10A, thereby filling in the steps on the main surface 10A and making the surface of the protective film 20 (processed film 20A) flat. The bonding device 30 used in the placement step S12 and the bonding step S13 of this bonding method may be one having a chuck table 31, a pressing member 32, a support member 33, etc., which are substantially the same as the bonding device 30 used in the bonding methods of the first and second embodiments described above. Details of this bonding device 30 are as described above in [4] Bonding device, and therefore will not be described here.

[0084] [9] Processing equipment The processing device 40 is not particularly limited as long as it has a configuration capable of executing the processing step S11. The processing device 40 may have the following configuration, for example. As shown in FIGS. 14(a) and 14(b), the processing device 40 has a first roller 41 and a second roller 42 that are arranged to face each other with the protective film 20 sandwiched therebetween. The first roller 41 is rotatably supported above the protective film 20 so as to come into contact with the base layer 21 of the protective film 20 . The second roller 42 is rotatably supported below the protective film 20 so as to come into contact with the adhesive layer 22 of the protective film 20 . The second roller 42 has a plurality of protrusions 43 formed on its circumferential surface. The first roller 41, the second roller 42 and the protrusions 43 are not particularly limited in terms of material, driving method, configuration, etc., as long as they are capable of processing the protective film 20.

[0085]

[10] Processing process As shown in Figure 14(a), the processing step S11 is a step of supplying the protective film 20 between the first roller 41 and the second roller 42 of the processing device 40, and sending out this protective film 20 from between the first roller 41 and the second roller 42 in the direction of travel indicated by the arrow in Figure 14(a). In the processing step S11, the protective film 20 sent out from between the first roller 41 and the second roller 42 becomes a processed film 20A in which portions of different thicknesses are formed.

[0086] The shape of the protective film 20 supplied to the processing device 40 is not particularly limited, and any of a circular shape, a square shape, a rectangular shape, and a strip shape in plan view can be used. The method for supplying the protective film 20 is not particularly limited, and either a batch method in which the protective film 20 is supplied one by one, or a continuous method in which the protective film 20 is supplied continuously can be used. In the processing step S11 shown in FIGS. 14(a) and 14(b), the shape of the supplied protective film 20 is a circular shape in plan view corresponding to the main surface 10A, and the supply method of the protective film 20 is a batch method.

[0087] In the processing device 40, when the protective film 20 is sandwiched between the first roller 41 and the second roller 42 and sent out in the traveling direction, the first roller 41 and the second roller 42 are rotated. The second roller 42 has protrusions 43 formed on its circumferential surface, and as shown in FIG. 14(b), the protrusions 43 come into contact with the protective film 20 as the second roller 42 rotates. The portion of the protective film 20 that comes into contact with the convex portion 43 is crushed in the thickness direction between the convex portion 43 and the first roller 41 .

[0088] The fleshy portion (irregularity absorbing layer 23) of the crushed portion of the protective film 20 flows to and shifts to the area adjacent to the crushed portion, as shown by the arrow in Figure 14(b), thereby increasing the amount of flesh in the adjacent area. Then, in the protective film 20, portions of different thicknesses are formed such that the crushed portions are thin and the portions adjacent to the crushed portions are thick, thereby obtaining a processed film 20A. This processed film 20A has a relatively thick region 201 among the portions having different thicknesses, and this relatively thick region 201 is used in the arrangement step S12.

[0089]

[11] Placement process The placement process S12 is a process in which, as shown in FIG. 15, the pressing member 32 is moved away from the semiconductor wafer 10 fixed to the chuck table 31, and the processed film 20A obtained in the processing process S11 is supplied onto the main surface 10A of the semiconductor wafer 10. In this placement step S12, the supplied processed film 20A is placed so as to cover the main surface 10A of the semiconductor wafer 10. In addition, a support member 33 is installed beside the semiconductor wafer 10 along the outer periphery of the second region 13. At this time, the processed film 20A is arranged so that the relatively thick region 201 corresponds to the second region 13, and the relatively thick region 201 is positioned above the blank region surface 101A.

[0090]

[12] Pasting process As shown in Figure 16, the adhesion process S13 is a process in which, with the edge of the protective film 20 supported by a support member 33, a pressing member 32 is brought close to the main surface 10A of the semiconductor wafer 10, and the protective film 20 is pressed against the main surface 10A by this pressing member 32 to adhere it. In the bonding process S13, on the first region 12 of the main surface 10A, the thick portion (irregularity absorption layer 23) of the processed film 20A that is sandwiched between the pressing member 32 and the bump 11 and crushed in the thickness direction deforms to conform to the irregularities of the bump 11 and fill in these irregularities. In the compression process S3, the edge of the protective film 20 is sandwiched between the support member 33 and the pressing member 32, thereby restricting the flow of flesh from the blank area surface 101A to the edge of the protective film 20 and preventing the flesh from escaping further outward from the periphery of the second area 13. Then, a portion of the flesh of the processed film 20A that has been crushed in the thickness direction flows onto the blank area 13B of the second area 13, as shown by the arrow in Figure 16, increasing the amount of flesh of the processed film 20A on the blank area surface 101A.

[0091] In the processed film 20A, a relatively thick region 201 was placed on the blank area surface 101A in the placement process S12 (see Figure 15), so the amount of thickness of the processed film 20A on the blank area surface 101A is further increased by adding the flow from above the first region 12 in the bonding process S13 (see Figure 16). Furthermore, in the processed film 20A, the area adjacent to the relatively thick region 201 is crushed and thinned in the above-mentioned processing step S11, so that it is possible to prevent the flesh from escaping further outward from the periphery of the second region 13 through this crushed and thinned area. Furthermore, in the bonding step S13, the portion that has been crushed and thinned in the processing step S11 is sandwiched between the support member 33 and the pressing member 32, thereby preventing the flesh from escaping further outward from the periphery of the second region 13.

[0092] Therefore, the processed film 20A has a relatively thick region 201 corresponding to the second region 13, and as the flesh flows in from above the first region 12, there is enough flesh to fill in the steps throughout the entire second region 13. Then, the processed film 20A on the blank area surface 101A, which has a sufficient amount of material, fills in the steps across the entire second area 13 by increasing the thickness. Furthermore, since the surface of processed film 20A is pressed by pressing member 32, it is not affected by the flow of the flesh portion and is made flat in accordance with pressing surface 32A. In the above description, the blank area 13B was used as an example of the second area 13, but in the same way as this blank area 13B, the thickness of the processed film 20A in the peripheral area 13A is shifted to one side so that it is thicker on the second area 13, thereby filling in the gap. Furthermore, the blank area 13B is not limited to those used primarily as identification areas as shown in Figures 1(a) and (b), and the same effect can be obtained with blank areas 13B as shown in Figures 11(a) and (b). That is, this bonding method is particularly useful when the target semiconductor wafer 10 has a blank area 13B having a flat blank area surface 101A in the second area 13, which is an area where no bumps are arranged. The surface of the protective film 20 attached to the semiconductor wafer 10 is then free of defects following the steps of the semiconductor wafer 10, and becomes a uniformly flat surface overall.

[0093]

[13] Processing step (fourth embodiment) The bonding method including this processing step is the fourth embodiment according to the fourth invention. This bonding method (fourth embodiment) is the same as the third embodiment described above except for the processing device 40 and the processing step S11 using the processing device 40, and detailed explanations other than the processing device 40 and the processing step S11 will be omitted. The adhering method (fourth embodiment) including this processing step, like the third embodiment, is included in the method for manufacturing a semiconductor component according to the fifth aspect of the invention. Furthermore, the semiconductor wafer 10 and protective film 20 used in the bonding method (fourth embodiment) including this processing step are the same as those used in the bonding methods of each of the above-mentioned embodiments including the third embodiment, and detailed explanations thereof will be omitted.

[0094] In this processing step S11, the processing device 40 has, as shown in Figures 17(a) and (b), a support pillar 45 erected next to the semiconductor wafer 10 so as to follow the outer peripheral edge of the second region 13 of the semiconductor wafer 10 supported and fixed on the chuck table 31, and a pressing body 46 arranged so as to face each other in the vertical direction with the protective film 20 sandwiched between the support pillar 45 and the pressing body 46. The support pillars 45 support the edges of the protective film 20 so that the protective film 20 is positioned above the semiconductor wafer 10, and are configured to lower to bring the protective film 20 closer to the main surface 10A of the semiconductor wafer 10. The pressing body 46 is formed in a disk shape and is configured to move downward to approach the support column 45. When the pressing body 46 descends, the protective film 20 supported by the supporting column 45 is sandwiched between the supporting column 45 and the pressing body 46, and is crushed and processed. The support columns 45 and the pressing members 46 are not particularly limited in terms of material, driving method, etc., as long as they are capable of processing the protective film 20 .

[0095] The processing step S11 using the processing device 40 described above will be described. As shown in FIG. 17(a), in processing step S11, the protective film 20 is crushed between the support pillar 45 and the pressing body 46 in the thickness direction. As shown in Figure 17(b), the fleshy portion (irregularity absorbing layer 23) of the crushed portion of the protective film 20 flows to and shifts to the area adjacent to the crushed portion, thereby increasing the amount of flesh in the adjacent area. Then, in the protective film 20, portions of different thicknesses are formed such that the crushed portions are thin and the portions adjacent to the crushed portions are thick, thereby obtaining a processed film 20A. The processed film 20A has a relatively thick region 201 among the portions of different thickness, and the position of this relatively thick region 201 corresponds to the second region 13 because the support pillars 45 are arranged along the outer peripheral edge of the second region 13 of the semiconductor wafer 10. Therefore, this processing step S11 can be performed including the placement step S12 by lowering the support pillar 45 as shown by the arrow in Figure 17(b) and placing the relatively thick region 201 of the processed film 20A above the blank area surface 101A. [Example]

[0096] The present invention will be specifically described below with reference to examples. [1] Protective film The protective film 20 used was attached to a 12-inch ring frame. The protective film 20 has the following configuration: the base layer 21, the adhesive layer 22, and the irregularity absorbing layer 23. Base layer 21 Material: polyethylene terephthalate film, thickness: 75 μm. Adhesive layer 22: Material: UV-curable acrylic adhesive, thickness: 10 μm. Unevenness absorption layer 23 Material: Thermoplastic ethylene-α-olefin copolymer (density: 0.861 g / cm 3 , G'(25): 5.15 MPa, G'(60): 0.14 MPa, Melt flow rate (190℃): 2.9 g / 10 min, Thickness: 510 μm.

[0097] [2] Semiconductor wafers The semiconductor wafer 10 provided with the bumps 11 had the following specifications: Diameter: 300mm. Thickness: 810μm. Material: Silicon. Average height of bump 11: 200 μm. Pitch of bumps 11: 400 μm. Non-bump area (peripheral area 13A): 3 mm from the outer periphery. Non-bump region (blank region 13B as identification region): The length of L1 in FIG. 1(a) is 90 mm, and the length of L2 in FIG. 1(a) is 7 mm.

[0098] [3] Applying the protective film Example 1 A vacuum laminator device (product number "TPL-0612W" manufactured by Takatori Corporation) was prepared, and a support member 33 (thickness: 1 mm, width W1: 5 mm) formed in a circular shape in a planar view was placed on the chuck table 31, and the pressing surface 32A of the pressing member 32 was made of iron. After the semiconductor wafer 10 was set inside the support member 33, the protective film 20 was supplied in a batch manner in the placement step S1, and the protective film 20 was placed so as to cover the main surface 10A of the semiconductor wafer 10. Thereafter, the heating temperature of the protective film 20 was set to 80°C, and the pressure applied by the pressing member 32 was set to 0.7 MPa. The bonding process S2 and the compression process S3 were carried out in that order to bond the protective film 20 to the main surface 10A of the semiconductor wafer 10. Then, the excess portion of the peripheral edge of the protective film 20 that protruded beyond the outer periphery of the semiconductor wafer 10 was cut off, and a sample of Example 1 was obtained. Comparative Example 1 A roll application device (product number "DR-3000II" manufactured by Nitto Seiki Co., Ltd.) was used, and a support member 33 was not used. In the same manner as in Example 1, except that a protective film 20 was applied to the main surface 10A of the semiconductor wafer 10, and the excess portion of the peripheral edge of the protective film 20 was cut off, thereby obtaining a sample of Comparative Example 1. Comparative Example 2 Except for the fact that the pressing surface 32A was made of silicone rubber and that no support member 33 was used, a protective film 20 was adhered to the main surface 10A of the semiconductor wafer 10 in the same manner as in Example 1, and the excess portion of the peripheral edge of the protective film 20 was cut off to obtain a sample of Comparative Example 2.

[0099] [4] Measurement of unevenness on the surface of protective film At the edge of the peripheral edge of the semiconductor wafer, the position shown in the explanatory diagram at the bottom of Figure 10 was set as the horizontal position of 0 mm and the vertical position of 0 μm, and the vertical position of the protective film surface at a predetermined horizontal position was measured. The results are shown in the graph at the top of Figure 10. The explanatory diagram at the bottom of FIG. 10 is drawn to correspond to the graph at the top in terms of horizontal position, but is drawn in an exaggerated manner in terms of vertical position.

[0100] As a result of measuring the vertical position of the protective film surface, the following was found from the graph in Figure 10. In Example 1, there was almost no difference in height between the vertical and horizontal positions, and the surface of the protective film was flat. In Comparative Example 1, the vertical position is low at a horizontal position of around 4 mm, i.e., in the second region, and the vertical position is high in the horizontal position range of 7 to 8 mm, i.e., in the first region. From these results, it was found that in Comparative Example 1, a dent was formed on the surface of the protective film in the second region in response to the step that occurred between the second region and the first region. Comparative Example 2 shows a tendency for the vertical position to become higher in the range where the horizontal position is 5 mm or less, i.e., in the second region, while showing a tendency for the vertical position to become lower in the range where the horizontal position is 7 mm or more, i.e., in the first region. From these results, it was found that in Comparative Example 2, the influence of the step that occurred between the second region and the first region affected the protective film to bend arched in the second region, and a dent was formed on the surface of the protective film in the first region. [Industrial Applicability]

[0101] The method for attaching a protective film of the present invention is widely used in applications for manufacturing semiconductor parts, and is particularly suitable for manufacturing parts with excellent productivity, since it has the property of being able to suitably flatten the surface of a protective film on a semiconductor wafer that is subjected to a back-grinding process. [Explanation of symbols]

[0102] 10;Semiconductor wafer, 10A; main surface, 11; bump, 12; first area, 13; second region, 13A; peripheral region, 13B; blank region, 14; chamfered part, 20;protective film, 20A; processed film, 21; base layer, 22; adhesive layer, 23; uneven absorption layer, 30; pasting device; 31; Chuck table, 32; pressing member, 32A; pressing surface, 33; support member, 33A; support surface, 40; processing equipment; 41; First Roller, 42; Second Roller, 43; convex part, 45; supporting column; 46;Pressure body.

Claims

1. A protective film adhering method comprising: a disposing step of disposing a protective film so as to cover a main surface of a semiconductor wafer; and an adhering step of pressing the protective film against the main surface to adhering the protective film, the main surface has a first region in which bumps are arranged and a second region which is a region including at least a part of the periphery of the main surface and in which no bumps are arranged; the attaching step includes a compressing step of compressing the protective film in its thickness direction, the compressing step is performed using a pressing member for pressing the protective film against the main surface and a support member installed along an outer periphery of the second region; A method for adhering a protective film, wherein the pressing member is formed in a disk shape, and the pressing surface that presses the protective film against the main surface is a flat surface.

2. the positioning step is a step of positioning the protective film such that an edge of the protective film extends outward from the periphery of the second region, The method for applying a protective film according to claim 1 , wherein the compression step is a step of compressing the edge portion by supporting the edge portion on the support member and sandwiching the edge portion between the support member and the pressing member.

3. The method for adhering a protective film according to claim 2 , wherein the support member has a support surface that supports the edge of the protective film and is parallel to the main surface or inclined so as to face the main surface.

4. The clearance between the main surface of the semiconductor wafer and the pressing surface of the pressing member is C １ and the clearance between the support surface of the support member and the pressing surface of the pressing member is C ２ In this case, C １ >C ２ 4. The method for adhering a protective film according to claim 3, wherein

5. The method for adhering a protective film according to claim 1 , wherein the protective film has a layer capable of exhibiting fluidity or plasticity.

6. The method for adhering a protective film according to claim 5 , wherein the compressing step is performed in a state in which the protective film is heated to develop the fluidity or the plasticity.

7. 7. A method for adhering a protective film according to claim 1, wherein, when the average height of the bumps is H1 and the average thickness of the protective film is H2, 0.5≦H2 / H1 holds.

8. A method for manufacturing a semiconductor component, comprising the method for adhering a protective film according to any one of claims 1 to 7.

9. A protective film used in the method for adhering a protective film according to any one of claims 1 to 7.

10. a processing step of processing the protective film to obtain a processed film; a placement step of placing the processed film so as to cover a main surface of a semiconductor wafer; a bonding step of pressing the processed film against the main surface to bond the film, the main surface has a first region in which bumps are arranged and a second region which is a region including at least a part of the periphery of the main surface and in which no bumps are arranged; the processing step is a step of forming portions of different thicknesses in the protective film to obtain the processed film, the arranging step is a step of arranging a relatively thick region of the processed film in the portion having different thicknesses so as to correspond to the second region, the attaching step is carried out using a pressing member for pressing the protective film against the main surface, A protective film adhering method, characterized in that the pressing member is formed in a disk shape, and the pressing surface that presses the protective film against the main surface is a flat surface.

11. The method for adhering a protective film according to claim 10 , wherein the protective film has a layer capable of exhibiting fluidity or plasticity.

12. The method for adhering a protective film according to claim 11 , wherein the processing step is carried out in a state in which the protective film is heated to exhibit the fluidity or the plasticity.

13. 13. A method for adhering a protective film according to claim 10, wherein, when the average height of the bumps is H1 and the average thickness of the protective film is H2, 0.5≦H2 / H1 holds.

14. A method for manufacturing a semiconductor component, comprising the method for adhering a protective film according to any one of claims 10 to 13.

15. A protective film used in the method for adhering a protective film according to any one of claims 10 to 13.

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