Method for manufacturing semiconductor device and expansion tape

Abstract

A method of manufacturing a semiconductor device is disclosed. This method for manufacturing a semiconductor device is provided with: a step A in which an expansion tape is selected, said expansion tape being provided with a base film and a pressure-sensitive adhesive layer containing a non-ultraviolet-curable pressure-sensitive adhesive, said pressure-sensitive adhesive layer having a 90-degree peel strength greater than a 180-degree peel strength with respect to a stainless steel plate; a step B in which a laminate is prepared, the laminate being provided with a tape and a plurality of semiconductor chips (chips) each having a first main surface and a second main surface; a step C in which the tape is heated and extended, thereby widening the space between the plurality of chips; and a step D of transferring the plurality of chips onto the pressure-sensitive adhesive layer of another tape of the same type as the tape, and peeling the tape at a peeling angle of more than 90 DEG with respect to the first main surfaces of the plurality of chips. Step C and Step D are repeated one or more times.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a semiconductor device and an extended band. Background Art

[0002] In recent years, with the miniaturization, high functionality and high integration of semiconductor devices, semiconductors have been increasingly becoming more multi-pin, high-density and with narrower wiring pitches. Therefore, a flabby sheaf such as a low-K layer is used to achieve miniaturization of pins or wiring or lower dielectric constants, and high reliability technology is required.

[0003] In this context, wafer level packaging (WLP) technology that achieves high reliability and high productivity is progressing. The WLP technology is characterized by direct assembly in the wafer state, and the wafer is singulated by dicing in its final process. Since it is assembled (sealed) once at the wafer level, it is a technology that achieves high productivity and high reliability. In the WLP technology, a redistribution layer is formed on the insulating film on the circuit surface of the semiconductor chip using polyimide, copper wiring, etc. to form a redistribution pattern, and metal pads, solder balls, etc. are mounted on the redistribution to form bumps for connecting terminals.

[0004] WLP includes semiconductor packages such as WLCSP (Wafer Level Chip Scale Package) and FI-WLP (Fan In Wafer Level Package) where the semiconductor chip and package area are the same, and semiconductor packages such as FO-WLP (Fan Out Wafer Level Package) where the package area is larger than the semiconductor chip area and the terminals can be extended to the outside of the chip. In this type of semiconductor package, miniaturization and thinning are progressing rapidly. In order to ensure reliability, sealing is performed at the wafer level, and after protecting the periphery of the semiconductor chip, a redistribution layer is formed, and each package is singulated.

[0005] In this semiconductor package, as described above, reliability is ensured by sealing at the wafer level and performing subsequent secondary mounting operations. Furthermore, even in the field of mounting single-function semiconductors such as discrete semiconductors, sealing is performed at the wafer level for the purpose of reducing cracks in the semiconductor chip during operation or stress applied to the periphery of the pad. Then, after protecting the periphery of the semiconductor chip, each package is singulated and the next process (SMT process, etc.) is carried out. Discrete semiconductors are mostly smaller than system LCIs, and in order to protect the semiconductor chip to a higher degree, it is particularly required to seal five or six sides of the semiconductor chip.

[0006] In order to seal the side of such a semiconductor chip, it is necessary to separate the wafer into pieces and then expand the interval between the semiconductor chips after manufacturing the semiconductor chips. For example, Patent Document 1 discloses a method of fixing a plurality of chips on an expansion tape, extending the expansion tape to expand the interval between the semiconductor chips, and then peeling the expansion tape from the semiconductor chips, and an expansion tape that can be used in the method.

[0007] Previous technical literature

[0008] Patent Literature

[0009] Patent Document 1: International Publication No. 2018 / 216621 Summary of the invention

[0010] Technical issues to be solved by the invention

[0011] However, it is considered that when the interval between semiconductor chips is expanded using an expansion tape, the interval between the semiconductor chips is expanded not only once, but the expansion process and the transfer process are repeated more than once in such a manner that the interval between the semiconductor chips is expanded and then transferred to other expansion tapes, and the interval between the semiconductor chips is expanded using other expansion tapes. In this case, as long as the expansion tape at the transfer destination (other expansion tape) is the same as the expansion tape at the transfer source, there will be no difference in the elongation during expansion, so the interval between the semiconductor chips can be effectively expanded. However, in the transfer between expansion tapes with the same adhesive force, there is a case where poor transfer occurs, in which the semiconductor chip is not transferred to the expansion tape at the transfer destination. If poor transfer occurs, it may cause a decrease in productivity.

[0012] Therefore, a main object of the present invention is to provide a method for manufacturing a semiconductor device that can sufficiently suppress transfer failure when transferring between the same expanded tapes when the tape expanding step and the transfer step are repeated one or more times.

[0013] Means for solving technical problems

[0014] The present inventors have studied to solve the above-mentioned problems and found that by using a predetermined expansion tape and peeling off the expansion tape of the transfer source at a predetermined angle, transfer defects when transferring between the same expansion tapes can be sufficiently suppressed, thereby completing the invention disclosed herein.

[0015] The present invention provides a method for manufacturing a semiconductor device as described in [1] or [2] and an extended band as described in [3] or [4].

[0016] [1] A method for manufacturing a semiconductor device having a semiconductor chip, comprising: a selection step of selecting an extension tape, wherein the extension tape comprises a substrate film and a pressure-sensitive adhesive layer provided on the substrate film and comprising a non-ultraviolet curing pressure-sensitive adhesive, wherein a first adhesive force of the pressure-sensitive adhesive layer relative to a stainless steel plate measured at 25°C at a peeling angle of 90° and a peeling speed of 300 mm / min is greater than a second adhesive force of the pressure-sensitive adhesive layer relative to the stainless steel plate measured at 25°C at a peeling angle of 180° and a peeling speed of 300 mm / min; and a preparation step of preparing a laminate, wherein the laminate comprises the extension tape and a plurality of semiconductor chips, wherein the semiconductor chips The body chip has a first main surface and a second main surface on the opposite side of the first main surface, and is fixed on the pressure-sensitive adhesive layer of the expansion tape through the first main surface; a tape expansion process, by heating and stretching the expansion tape, widening the intervals between the multiple semiconductor chips fixed on the expansion tape; and a transfer and peeling process, transferring the multiple semiconductor chips to the pressure-sensitive adhesive layer of another expansion tape of the same type as the expansion tape to fix the second main surfaces of the multiple semiconductor chips, and peeling the expansion tape at a peeling angle exceeding 90° relative to the first main surfaces of the multiple semiconductor chips, and repeating the tape expansion process and the transfer and peeling process one or more times in sequence.

[0017] [2] The method for manufacturing a semiconductor device according to [1], wherein the first adhesive force is greater than or equal to 1.2 N / 25 mm.

[0018] [3] An expansion tape comprising a substrate film and a pressure-sensitive adhesive layer disposed on the substrate film and comprising a non-ultraviolet curing pressure-sensitive adhesive, wherein a first adhesive force of the pressure-sensitive adhesive layer relative to a stainless steel plate measured at 25°C at a peeling angle of 90° and a peeling speed of 300 mm / min is greater than a second adhesive force of the pressure-sensitive adhesive layer relative to the stainless steel plate measured at 25°C at a peeling angle of 180° and a peeling speed of 300 mm / min.

[0019] [4] The expansion tape according to [3], wherein the first adhesive force is greater than or equal to 1.2 N / 25 mm.

[0020] The reason why poor transfer when transferring between the same expansion tapes can be fully suppressed by using a specified expansion tape and peeling off the expansion tape of the transfer source at a specified angle is not necessarily clear, but the inventors speculate that this is because the first adhesive force of the expansion tape is greater than the second adhesive force, and by peeling off the expansion tape of the transfer source at a specified angle, the adhesive force between the expansion tape of the transfer destination and the semiconductor chip becomes greater than the adhesive force between the expansion tape of the transfer source and the semiconductor chip, and it becomes easier to transfer the semiconductor chip to the expansion tape of the transfer destination.

[0021] Effects of the Invention

[0022] According to the present invention, there is provided a method for manufacturing a semiconductor device that can sufficiently suppress transfer failure when transferring between the same expanded tapes when the tape expansion step and the transfer step are repeated more than once. Also, according to the present invention, there is provided an expanded tape that can be preferably used in the method for manufacturing such a semiconductor device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic cross-sectional view showing one embodiment of an expansion zone.

[0024] Figure 2 is a schematic cross-sectional view for explaining one embodiment of a method for manufacturing a semiconductor device. Figure 2 middle, Figure 2 (a) Figure 2 (b) and Figure 2 (c) is a diagram showing each process.

[0025] Figure 3 is a schematic cross-sectional view for explaining one embodiment of a method for manufacturing a semiconductor device. Figure 3 middle, Figure 3 (a) Figure 3 (b) and Figure 3 (c) is a diagram showing each process.

[0026] Figure 4 is a schematic cross-sectional view for explaining one embodiment of a method for manufacturing a semiconductor device. Figure 4 middle, Figure 4 (a) Figure 4 (b) Figure 4 (c) and Figure 4 (d) is a diagram showing each process.

[0027] Figure 5 is a schematic cross-sectional view for explaining one embodiment of a method for manufacturing a semiconductor device. Figure 5 middle, Figure 5 (a) and Figure 5 (b) is a diagram showing each process. DETAILED DESCRIPTION

[0028] Hereinafter, the present embodiment will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments. In the following embodiments, the constituent elements (including steps, etc.) are not necessary except for those specifically indicated. The same symbols are marked on the same or equivalent parts, and repeated descriptions are omitted. In addition, regarding the positional relationship such as up, down, left, and right, unless otherwise specified, it is based on the positional relationship shown in the accompanying drawings. The sizes of the constituent elements in each figure are conceptual, and the relative relationship between the sizes of the constituent elements is not limited to those shown in the figures.

[0029] The same is true for the numerical value and its range of the present invention, and the present invention is not limited thereto. In this specification, the numerical range represented by "~" indicates the range including the numerical values ​​recorded before and after "~" as the minimum and maximum values, respectively. In the numerical range recorded in stages in this specification, the upper limit or lower limit recorded in a numerical range can be replaced by the upper limit or lower limit of the numerical range recorded in other stages. And, in the numerical range recorded in this specification, the upper limit or lower limit of its numerical range can be replaced by the value shown in the embodiment.

[0030] In this specification, the term "layer" includes not only a structure of a shape formed on the entire surface but also a structure of a shape formed on a portion when viewed from a top view. Furthermore, in this specification, the term "process" is not limited to an independent process, but is also included in this term as long as the desired effect of the process is achieved even if it cannot be clearly distinguished from other processes.

[0031] In the present specification, (meth)acrylate refers to acrylate or its corresponding methacrylate. The same applies to other similar expressions such as (meth)acrylic copolymers.

[0032] Each component and material exemplified in the present specification may be used alone or in combination of two or more unless otherwise specified.

[0033] [Method for manufacturing semiconductor device]

[0034] A method for manufacturing a semiconductor device according to an embodiment of the present invention relates to a method for manufacturing a semiconductor device having a semiconductor chip, and includes a selection step, a preparation step, a tape expansion step, and a transfer and peeling step.

[0035] In the manufacturing method of the semiconductor device of the present embodiment, after the tape expansion process using an expansion tape (expansion tape of the transfer source), transfer to other expansion tapes (expansion tape of the transfer destination), and further use other expansion tapes until finally transfer to the carrier, the tape expansion process and the transfer process are repeated one or more times in sequence.

[0036] The method for manufacturing a semiconductor device may further include the following steps, for example.

[0037] ·Tension maintaining process to maintain the tension of the stretched expansion belt

[0038] ·Carrier transfer process of transferring multiple semiconductor chips to a carrier

[0039] Figure 1 This is a schematic cross-sectional view showing one embodiment of an expansion zone. Figure 2 , Figure 3 , Figure 4 and Figure 5 This is a schematic cross-sectional view for explaining one embodiment of a method for manufacturing a semiconductor device.

[0040] (Selected process)

[0041] In the selection step, an extension band satisfying a predetermined condition is selected from the extension bands. Figure 1 The expandable tape 1 shown in FIG. 1 includes a base film 1 a and a pressure-sensitive adhesive layer 1 b including a non-ultraviolet curing pressure-sensitive adhesive provided on the base film 1 a. The structure of the expandable tape will be described below.

[0042] Examples of the substrate film 1a include polyester films such as polyethylene terephthalate films; polyolefin films such as homopolymers of α-olefins such as polytetrafluoroethylene films, polyethylene films, polypropylene films, polymethylpentene films, polyvinyl acetate films, poly-4-methylpentene-1, and copolymers thereof, and ionomers of homopolymers or copolymers thereof; polyvinyl chloride films; polyimide films; and various plastic films such as urethane resin films. The substrate film 1a is not limited to a single-layer film, and may be a multilayer film obtained by combining two or more plastic films or a multilayer film obtained by combining two or more plastic films of the same kind.

[0043] The base film 1a may be a polyolefin film or a urethane resin film from the viewpoint of tensile stress and elongation. The base film 1a may contain various additives such as an anti-blocking agent as required.

[0044] The thickness of the substrate film 1a may be 50 to 500 μm, 60 to 400 μm, or 70 to 300 μm. If the thickness of the substrate film 1a is 50 μm or more, there is a tendency to improve the elongation. If the thickness of the substrate film 1a is 500 μm or less, there is a tendency to suppress the occurrence of strain or the deterioration of operability.

[0045] In the case where the substrate film is a multilayer film, the thickness of the substrate film as a whole is preferably adjusted within the above range. The substrate film may be subjected to chemical or physical surface treatment as required in order to improve the adhesion with the pressure-sensitive adhesive layer. Examples of surface treatments include corona treatment, chromic acid treatment, ozone exposure, flame exposure, high voltage electric shock exposure, and ionizing radiation treatment.

[0046] The pressure-sensitive adhesive layer 1b includes a non-ultraviolet curing pressure-sensitive adhesive. A non-ultraviolet curing pressure-sensitive adhesive is a pressure-sensitive adhesive that exhibits a certain adhesiveness under short-term pressure, and is a pressure-sensitive adhesive whose adhesiveness does not change significantly before and after irradiation with ultraviolet rays. As long as the non-ultraviolet curing pressure-sensitive adhesive is a pressure-sensitive adhesive that can form a pressure-sensitive adhesive layer having a first adhesive force greater than a second adhesive force, any previously known pressure-sensitive adhesive can be used without particular limitation. Examples of the non-ultraviolet curing pressure-sensitive adhesive include natural rubber-based, synthetic rubber-based, acrylic resin-based, polyvinyl ether resin-based, urethane resin-based, silicone resin-based, and the like.

[0047] The thickness of the pressure-sensitive adhesive layer 1b can be generally 1 to 100 μm, or 2 to 50 μm or 5 to 40 μm. If the thickness of the pressure-sensitive adhesive layer 1b is 1 μm or more, sufficient adhesion to the semiconductor chip 2 can be ensured, so that the semiconductor chip can be prevented from flying to a higher degree during the tape expansion process. On the other hand, if the thickness of the pressure-sensitive adhesive layer 1b is 100 μm or less, it is economically advantageous.

[0048] Furthermore, the thickness of the pressure-sensitive adhesive layer 1b may be 10 μm or more, or may be 20 to 50 μm or 30 to 50 μm. If the thickness of the pressure-sensitive adhesive layer 1b is 10 μm or more, a dicing tape is not used, and the substrate film 1a will not be damaged (cut into, etc.) when the semiconductor wafer is diced on the expansion tape 1, so the step of dicing the semiconductor wafer on the dicing tape and transferring (laminating) it to the expansion tape 1 in the preparation step can be omitted.

[0049] The expansion tape 1 can be manufactured according to the technology known in the technical field. For example, it can be manufactured according to the following method. First, a varnish containing the components and solvent constituting the pressure-sensitive adhesive layer is applied to the protective film by a knife coating method, a roller coating method, a spray coating method, a gravure coating method, a rod coating method, a curtain coating method, etc., and a pressure-sensitive adhesive layer is formed by removing the solvent (organic solvent). The conditions for removing the solvent can be, for example, 50 to 200° C. and a heating condition of 0.1 to 90 minutes. As long as the conditions for removing the solvent do not affect the generation of voids or viscosity adjustment in each process, the solvent can be removed until it becomes less than 1.5% by mass. Then, the protective film and the substrate film 1a with a pressure-sensitive adhesive layer are stacked under a temperature condition of 25 to 60° C. so that the pressure-sensitive adhesive layer 1b is opposite to the substrate film 1a, and the expansion tape 1 can be obtained. When using the expansion tape, the protective film is usually peeled off and then used.

[0050] Examples of the protective film include A-63 (manufactured by TOYOBO CO., LTD., mold release agent: modified silicone type) and A-31 (manufactured by TOYOBO CO., LTD., mold release agent: Pt-based silicone type).

[0051] The thickness of the protective film can be appropriately selected within a range that does not impair workability. From the perspective of economic efficiency, the thickness of the protective film can be 100 μm or less. The thickness of the protective film can be 10 to 75 μm or 25 to 50 μm. If the thickness of the protective film is 10 μm or more, there is a tendency that it is difficult to cause undesirable conditions such as film breakage when making the expansion tape. In addition, if the thickness of the protective film is 75 μm or less, the protective film can be easily peeled off when using the expansion tape.

[0052] In the selection process, in the extended tape having such a structure, the first adhesive force of the pressure-sensitive adhesive layer 1b relative to the stainless steel plate measured at 25°C at a peeling angle of 90° and a peeling speed of 300 mm / min, and the second adhesive force of the pressure-sensitive adhesive layer 1b relative to the stainless steel plate measured at 25°C at a peeling angle of 180° and a peeling speed of 300 mm / min are measured, and an extended tape in which the first adhesive force is greater than the second adhesive force is selected.

[0053] The first adhesive force of the pressure-sensitive adhesive layer 1b relative to the stainless steel plate is greater than the second adhesive force, for example, it can be 1.2N / 25mm or more. Here, the first adhesive force is the 90° peel strength measured at a peeling angle of 90° and a peeling speed of 300mm / minute at 25°C. The 90° peel strength can be measured, for example, by the following method. First, the extended tape is cut out with a width of 25mm×length of 100mm, and the surface of the pressure-sensitive adhesive layer 1b side is attached to the stainless steel plate (stainless steel support plate), and it is used as a measurement sample. Then, in a state where the stainless steel plate (stainless steel support plate) side of the measurement sample is fixed, a tensile tester (manufactured by Shimadzu Corporation, Autograph AGS-1000) is used to peel off the pressure-sensitive adhesive layer 1b under the conditions of a measurement temperature of 25°C, a peeling angle of 90° and a peeling speed of 300mm / minute, thereby being able to measure the 90° peel strength. The first adhesive force may be 1.3 N / 25 mm or more or 1.5 N / 25 mm or more. The upper limit of the first adhesive force may be, for example, 3.0 N / 25 mm or less, 2.5 N / 25 mm or less or 2.0 N / 25 mm or less.

[0054] The second adhesive force of the pressure-sensitive adhesive layer 1b relative to the stainless steel plate is less than the first adhesive force, for example, it can be less than 1.2N / 25mm. Here, the second adhesive force is a 180° peel strength measured at a peel angle of 180° and a peel speed of 300mm / min at 25°C. The 180° peel strength can be measured in the same manner as the above-mentioned 90° peel strength except that the peel angle is changed from 90° to 180°. The second adhesive force can be less than 1.1N / 25mm or less than 1.0N / 25mm. The lower limit of the second adhesive force can be, for example, more than 0.1N / 25mm, more than 0.3N / 25mm, or more than 0.5N / 25mm.

[0055] The difference between the first adhesive force and the second adhesive force may be, for example, 0.1 N / 25 mm or more, 0.3 N / 25 mm or more, or 0.5 N / 25 mm or more. The difference between the first adhesive force and the second adhesive force may be, for example, 1.0 N / 25 mm or less.

[0056] The first adhesive force may be, for example, 1.1 times or more, 1.3 times or more, or 1.5 times or more relative to the second adhesive force. The first adhesive force may be, for example, 3.0 times or less relative to the second adhesive force.

[0057] Specific examples of the expandable tape having a first adhesive force greater than a second adhesive force include a dicing expandable film HAE-1720 (product name, manufactured by Showa Denko Materials Co., Ltd.).

[0058] (Preparation process)

[0059] In the preparation step, a laminate 10 is prepared, wherein the laminate 10 includes an expansion tape 1 and a plurality of semiconductor chips 2, wherein the semiconductor chips 2 have a first main surface 2A and a second main surface 2B opposite to the first main surface 2A, and are fixed to the pressure-sensitive adhesive layer 1b of the expansion tape 1 via the first main surface 2A. Furthermore, the semiconductor chips 2 may have a circuit surface provided with a solder pad (circuit) 3. Figure 2 , a method of fixing the first main surface 2A of the semiconductor chip 2 on the opposite side to the circuit surface to the expansion tape 1 is shown ( Figure 2 (a)), however, the laminated body 10 may be in a form in which the circuit surface on the second main surface 2B side of the semiconductor chip 2 is fixed to the expansion tape 1.

[0060] The laminated body 10 can be produced, for example, by laminating semiconductor wafers on a dicing tape or the like, dicing the wafers with a blade or laser to produce a plurality of individual semiconductor chips, and transferring the individual semiconductor chips to the expansion tape 1 .

[0061] The cutting may be performed by a blade or by invisible cutting in which a relaxation layer is formed by laser and then expanded. In addition, from the viewpoint of improving productivity, the stacked body 10 may be manufactured by directly laminating a semiconductor wafer on the expanded tape 1 by omitting the transfer process and cutting the semiconductor wafer by the above method.

[0062] From the viewpoint of improving productivity and reducing costs, the initial spacing between the semiconductor chips 2 (the spacing between the semiconductor chips before the band expansion process) is preferably narrow, for example, it can be less than 100 μm, or less than 80 μm or less than 60 μm. If the initial spacing between the semiconductor chips 2 is wide due to the cutting of the semiconductor wafer, waste of semiconductor wafers will occur, so from the viewpoint of reducing costs, it is preferably narrow. When widening the spacing between the semiconductor chips 2, from the viewpoint of avoiding stress on the semiconductor chips 2, the initial spacing between the semiconductor chips 2 can be more than 10 μm. If the initial spacing between the semiconductor chips 2 is less than 10 μm, there is a tendency that the expansion band area between the plurality of semiconductor chips 2 is small and difficult to widen.

[0063] The size of the semiconductor chip 2 is not particularly limited, but may be, for example, 25 mm 2 (5 mm×5 mm) or less, or 9 mm 2 (3 mm×3 mm) or less.

[0064] The type of the solder pad 3 on the circuit surface of the semiconductor chip 2 is not particularly limited as long as it can be formed on the circuit surface of the semiconductor chip 2. It can be a bump (protruding electrode) such as a copper bump or a solder bump, or a relatively flat metal pad such as a Ni / Au plated solder pad.

[0065] The semiconductor chip 2 may include a resin portion for protection from the outside, an external terminal for electrically connecting the semiconductor element, and the like.

[0066] In this specification, the term semiconductor chip includes a semiconductor package having a resin portion for external protection, an external terminal for electrically connecting a semiconductor element, etc. When a semiconductor package is used in the preparation process, for example, after laminating a semiconductor package produced at the substrate level on a dicing tape or the like, and cutting with a blade or laser to obtain a plurality of individual semiconductor chips, the semiconductor chips can be transferred to an expansion tape to produce a laminate 10.

[0067] (With extended process)

[0068] In the tape expansion step, the expansion tape 1 is heated and stretched, thereby widening the intervals between the plurality of semiconductor chips 2 fixed on the expansion tape 1 ( Figure 2 (b)).

[0069] As a method for stretching the expansion tape 1, for example, a push-up method and a stretching method can be cited. In the push-up method, after the expansion tape 1 is fixed, the expansion tape 1 is stretched by raising a worktable having a predetermined shape. In the stretching method, after the expansion tape 1 is fixed, the expansion tape 1 is stretched in a predetermined direction parallel to the surface of the expansion tape to stretch the expansion tape 1. From the perspective of uniformly stretching the intervals between semiconductor chips and the perspective of a small and compact device area required (occupied), the push-up method can be used.

[0070] The stretching conditions can be appropriately set according to the properties of the extension tape 1. For example, the push-up amount (stretching amount) in the case of the push-up method can be 10 to 150 mm or 10 to 120 mm. If the push-up amount is 10 mm or more, it is easy to widen the interval between multiple semiconductor chips, and if the push-up amount is 150 mm or less, it becomes difficult for the semiconductor chips to scatter or shift in position.

[0071] The heating temperature of the tape extension process (temperature during extension) can be appropriately set according to the properties of the extension tape 1. The temperature during extension can be, for example, 25 to 200°C, or 25 to 150°C or 30 to 100°C. If the temperature during extension is 25°C or higher, it becomes easy to extend the extension tape 1. If the temperature during extension is 200°C or lower, it is possible to prevent the positional displacement of the semiconductor chip (peeling between the extension tape and the semiconductor chip) caused by the thermal expansion or low elasticity of the extension tape 1, and the scattering of the semiconductor chip, etc., to a higher degree. The heating temperature of the tape extension process can be, for example, 50°C.

[0072] The push-up speed can also be appropriately set according to the properties of the expansion tape 1. The push-up speed can be, for example, 0.1 to 500 mm / second, 0.1 to 300 mm / second, or 0.1 to 200 mm / second. If the push-up speed is 0.1 mm / second or more, the productivity can be further improved. If the push-up speed is 500 mm / second or less, the peeling between the expansion tape and the semiconductor chip becomes difficult to occur.

[0073] The intervals between the plurality of semiconductor chips 2 after the tape expansion process are arbitrarily widened to appropriate intervals to ensure the space required for setting the redistribution pattern and the pads for the connection terminals outside the region of the semiconductor chip 2. The expansion rate of the tape expansion process relative to the intervals between the plurality of semiconductor chips 2 before the tape expansion process may be, for example, more than 100% and less than 300%.

[0074] (Tension holding process)

[0075] In the tension maintaining step, the stretched expansion belt 1 is fixed by using the fixing jig 4 to maintain the tension of the expansion belt 1 ( Figure 2 (c)). This can prevent the stretched expansion band 1 from returning to its original state.

[0076] There are no particular restrictions on the method of maintaining the tension of the expansion tape 1 as long as the tension can be maintained and the interval between the semiconductor chips cannot be restored to the original state. For example, there can be a method of fixing using a fixing fixture such as a clamp ring (manufactured by TECHNOVISION Corporation), a method of heating the outer periphery of the expansion tape to shrink it (thermal shrinkage) to maintain the tension, etc.

[0077] (Transfer and peeling process)

[0078] In the transfer and peeling step, the plurality of semiconductor chips 2 are transferred onto the pressure-sensitive adhesive layer 1'b of another expansion tape 1' (base film 1'a and pressure-sensitive adhesive layer 1'b) of the same type as the expansion tape 1 ( Figure 3 (a)) to fix the second main surface 2B (circuit surface of the semiconductor chip 2) of the plurality of semiconductor chips 2, and to peel off the expansion tape 1 at a peeling angle exceeding 90° relative to the first main surface 2A of the plurality of semiconductor chips 2 ( Figure 3 (b)).

[0079] The transfer method (lamination method) is not particularly limited, but a roll press, a diaphragm laminator, a vacuum roll press, or a vacuum diaphragm laminator can be used.

[0080] The transfer conditions (lamination conditions) can be appropriately set according to the properties of the expansion tape 1 and the properties of the semiconductor chip 2. For example, when a roller press is used, the temperature conditions can be, for example, 25 to 200°C, 25 to 150°C or 25 to 100°C. If the temperature condition is above 25°C, it becomes easy to transfer the semiconductor chip 2 to the expansion tape 1. If the temperature condition is below 200°C, it is possible to prevent the positional displacement of the semiconductor chip 2 (peeling between the expansion tape 1 and the semiconductor chip) caused by the strain or sagging due to the thermal expansion and low elasticity of the expansion tape 1, the scattering of the semiconductor chip 2, etc. to a higher degree. When a diaphragm-type laminator is used, the temperature conditions can be the same as those of the above-mentioned roller press. The pressing time can be 5 to 300 seconds, 5 to 200 seconds or 5 to 100 seconds. If the pressing time is more than 5 seconds, the semiconductor chip 2 is easily transferred to the expansion tape 1. If the pressing time is less than 300 seconds, the productivity can be improved. The pressure during the crimping may be 0.1 to 3 MPa, 0.1 to 2 MPa or 0.1 to 1 MPa. If the pressure during the crimping is 0.1 MPa or more, the semiconductor chip 2 is easily transferred to the expansion tape 1, and if the pressure during the crimping is 3 MPa or less, the damage to the semiconductor chip 2 can be reduced.

[0081] Next, the extended tape 1 is peeled off at a peeling angle exceeding 90° with respect to the first main surfaces 2A of the plurality of semiconductor chips 2. For example, the extended tape 1 can be peeled off by pulling the extended tape 1 in the pulling direction F by means of the peeling member 5, thereby peeling off the extended tape 1 from the first main surfaces 2A of the plurality of semiconductor chips 2. Here, the peeling angle is the first main surface 2A of the semiconductor chip 2 ( Figure 2 (b) X(2A)) and stretching direction F( Figure 2 When the angle α exceeds 90°, the adhesive force between the expansion tape 1' and the semiconductor chip 2 becomes greater than the adhesive force between the expansion tape 1 and the semiconductor chip 2, and the semiconductor chip 2 tends to be easily transferred to the expansion tape 1'. The angle α may be greater than 100°, greater than 110°, greater than 120°, greater than 130°, greater than 140°, or greater than 150°, and may be less than 180° or less than 180°.

[0082] The peeling speed when peeling the expansion tape 1 can be, for example, 1 to 1000 mm / min. The peeling temperature when peeling the expansion tape 1 can be arbitrarily set, for example, 25 to 200° C. In addition, when peeling the expansion tape 1, by heating the expansion tape 1′ (the expansion tape of the transfer destination) and not heating the expansion tape 1 (the expansion tape of the transfer source), there is a tendency that the expansion tape 1 and the semiconductor chip 2 are easily peeled off.

[0083] In this way, a laminated body 20 ( ) including an expansion tape 1 ′ and a plurality of semiconductor chips 2 fixed to the second main surface 2B (circuit surface of the semiconductor chip 2 ) on the pressure-sensitive adhesive layer 1 ′b of the expansion tape 1 ′ can be obtained. Figure 3 (c)).

[0084] Repeat the tape expansion process and the transfer peeling process one or more times in sequence. Based on the research of the present inventors, it was found that if an expansion tape is used and a large expansion rate is to be expanded once (for example, an expansion rate of more than 300% each time), there is a tendency for the positional deviation of the semiconductor chip to become larger. According to the method for manufacturing a semiconductor device of the present invention characterized by repeating the tape expansion process and the transfer process one or more times in sequence, the spacing between semiconductor chips can be expanded in stages, and the spacing between single-chip semiconductor chips can be made relative to the spacing between initial semiconductor chips. For example, even when the expansion is to a target range of more than 300%, the positional deviation of the semiconductor chip can be sufficiently suppressed.

[0085] In the first repeated tape expansion step, the expansion tape 1' is heated and stretched, thereby widening the intervals between the plurality of semiconductor chips 2 fixed on the expansion tape 1' ( Figure 4 (a) Figure 4 (b)).

[0086] In the first repeated transfer and peeling step, the plurality of semiconductor chips 2 are transferred onto the pressure-sensitive adhesive layer 1"b of another expansion tape 1" (substrate film 1"a and pressure-sensitive adhesive layer 1"b) of the same type as the expansion tape 1' ( Figure 4 (c)) to fix the first main surface 2A of the plurality of semiconductor chips 2, and to peel off the extended tape 1' at a peeling angle exceeding 90° relative to the second main surface 2B of the plurality of semiconductor chips 2 ( Figure 4 (d)). Here, the peeling angle is the second main surface 2B of the semiconductor chip 2 ( Figure 4 (d) X(2B)) and stretching direction F( Figure 4 The preferred embodiment of the angle β may be the same as the preferred embodiment of the angle α.

[0087] In this way, a laminated body 30 ( ) including an expansion tape 1 ″ and a plurality of semiconductor chips 2 fixed to the pressure-sensitive adhesive layer 1 ″ b of the expansion tape 1 ″ via the first main surface 2A can be obtained. Figure 5 (a)).

[0088] The tape expansion process and the transfer peeling process are repeated until the final transfer to the carrier, using other expansion tapes of the same type as the expansion tapes 1, 1', 1". The repetition is more than 1 time (the total number of implementations of the tape expansion process is more than 2 times). It can also be implemented more than 2 times (the total number of implementations of the tape expansion process is more than 3 times), more than 3 times (the total number of implementations of the tape expansion process is more than 4 times), more than 4 times (the total number of implementations of the tape expansion process is more than 5 times), or more than 5 times (the total number of implementations of the tape expansion process is more than 6 times). It can also be implemented less than 10 times (the total number of implementations of the tape expansion process is less than 11 times).

[0089] (Carrier transfer process)

[0090] In the carrier transfer process, after the tape expansion process and the transfer peeling process are repeated one or more times, a plurality of semiconductor chips 2 are transferred (laminated) from the expansion tape to the carrier 6. Finally, by peeling the expansion tape from the semiconductor chip 2, a semiconductor device 40 ( Figure 5 (b)).

[0091] The transfer method (lamination method) can be appropriately set according to the properties of the expansion tape 1, the properties of the semiconductor chip 2, and the properties of the carrier 6. The lamination method and transfer conditions (lamination conditions) of the carrier transfer step may be the same as those of the transfer peeling step.

[0092] The carrier 6 is not particularly limited as long as it can withstand the temperature and pressure during transfer (the chip will not be damaged and the chip spacing will not change), and can also withstand the temperature and pressure during sealing. For example, when the sealing temperature is 100-200°C, it is preferably heat-resistant enough to withstand the temperature range. In addition, the thermal expansion coefficient can be below 100ppm / °C, below 50ppm / °C, or below 20ppm / °C. If the thermal expansion coefficient is large, there is a tendency for undesirable situations such as positional displacement of the semiconductor chip to occur. In addition, if the thermal expansion coefficient is smaller than the thermal expansion coefficient of the semiconductor chip, strain or warping will occur, so it can be above 3ppm / °C.

[0093] The material of the carrier 6 is not particularly limited, and examples thereof include silicon (wafer), glass, SUS, iron, Cu, or other plates, glass epoxy substrates, and the like.

[0094] The thickness of the carrier 6 may be 100 to 5000 μm, 100 to 4000 μm or 100 to 3000 μm. If the thickness of the carrier is 100 μm or more, the handling property tends to be improved. If the thickness of the carrier is 5000 μm or less, it is economically advantageous.

[0095] The carrier 6 can be composed of a plurality of layers. In addition to the layer imparting heat resistance and operability, the carrier 6 can also be provided with a temporary fixing material layer laminated with an adhesive imparting layer or a temporary fixing material from the viewpoint of imparting adhesion control. These layers can be arbitrarily arranged in consideration of the adhesion of the semiconductor chip or the expansion tape. In the case of being composed of a plurality of layers, the thickness thereof is not particularly limited, but, for example, can be 1 to 300 μm, or can be 1 to 200 μm. If the thickness is 1 μm or more, sufficient adhesion to the semiconductor chip can be ensured. On the other hand, if the thickness is 300 μm or less, it is economically advantageous.

[0096] According to the method for manufacturing a semiconductor device of the present embodiment, when the tape expansion process and the transfer process are repeated more than once, poor transfer can be sufficiently suppressed when transferring between the same expansion tapes. The reason why poor transfer can be sufficiently suppressed when transferring between the same expansion tapes by using a specified expansion tape and peeling off the expansion tape of the transfer source at a specified angle is not necessarily clear, but the inventors of the present invention speculate that this is because the first adhesive force of the expansion tape is greater than the second adhesive force, and the expansion tape of the transfer source is peeled off at a specified angle, so that the adhesive force between the expansion tape of the transfer destination and the semiconductor chip becomes greater than the adhesive force between the expansion tape of the transfer source and the semiconductor chip, and it becomes easy to transfer the semiconductor chip to the expansion tape of the transfer destination.

[0097] Example

[0098] Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to these examples.

[0099] [Expansion band preparation]

[0100] As the expansion tape, a dicing expansion film HAE-1720 (product name, manufactured by Showa Denko Materials Co., Ltd.) was prepared.

[0101] [Measurement of the first adhesive force (90° peel strength)]

[0102] First, the expansion tape was cut into a width of 25 mm × a length of 100 mm, and the surface of the pressure-sensitive adhesive layer 1b was attached to a stainless steel plate (stainless steel support plate), and used as a test sample. Then, the pressure-sensitive adhesive layer 1b was peeled off using a tensile tester (manufactured by Shimadzu Corporation, Autograph AGS-1000) under the conditions of a measurement temperature of 25°C, a peeling angle of 90°, and a peeling speed of 300 mm / min, while the stainless steel plate (stainless steel support plate) side of the test sample was fixed, and the 90° peel strength was measured. The 90° peel strength was 1.6 N / 25 mm.

[0103] [Measurement of the second adhesive force (180° peel strength)]

[0104] 180° Peel Strength The 180° peel strength was measured in the same manner as the above-mentioned 90° peel strength except that the peel angle was changed from 90° to 180°. The 180° peel strength was 0.8 N / 25 mm.

[0105] Explanation of symbols

[0106] 1, 1', 1"- expansion tape, 1a, 1'a, 1"a- base film, 1b, 1'b, 1"b- pressure-sensitive adhesive layer, 2- semiconductor chip, 2A- first main surface, 2B- second main surface, 3- soldering pad (circuit), 4- fixing fixture, 5- peeling member, 6- carrier, 10, 20, 30- laminate, 40- semiconductor device.

Claims

1. A method for manufacturing a semiconductor device having a semiconductor chip, comprising: A selecting step of selecting an extension tape, wherein the extension tape comprises a substrate film and a pressure-sensitive adhesive layer provided on the substrate film and comprising a non-ultraviolet curing pressure-sensitive adhesive, and wherein a first adhesive force of the pressure-sensitive adhesive layer to a stainless steel plate measured at 25° C. at a peeling angle of 90° and a peeling speed of 300 mm / min is greater than a second adhesive force of the pressure-sensitive adhesive layer to the stainless steel plate measured at 25° C. at a peeling angle of 180° and a peeling speed of 300 mm / min; a preparation step of preparing a laminated body, the laminated body comprising the expansion tape and a plurality of semiconductor chips, the semiconductor chips having a first main surface and a second main surface opposite to the first main surface, and being fixed to the pressure-sensitive adhesive layer of the expansion tape via the first main surface; a tape expansion step of widening the intervals between the plurality of semiconductor chips fixed on the expansion tape by heating and stretching the expansion tape; and a transfer and peeling step of transferring the plurality of semiconductor chips onto a pressure-sensitive adhesive layer of another expansion tape of the same type as the expansion tape to fix the second main surfaces of the plurality of semiconductor chips, and peeling the expansion tape at a peeling angle exceeding 90° relative to the first main surfaces of the plurality of semiconductor chips, The above-mentioned tape expansion step and transfer and peeling step are sequentially repeated once.

2. The method for manufacturing a semiconductor device according to claim 1, wherein: The first adhesive force is greater than 1.2 N / 25 mm.

3. An expansion tape comprising a base film and a pressure-sensitive adhesive layer provided on the base film and containing a non-ultraviolet curing pressure-sensitive adhesive, The first adhesive force of the pressure-sensitive adhesive layer to the stainless steel plate measured at 25°C at a peeling angle of 90° and a peeling speed of 300 mm / min is greater than the second adhesive force of the pressure-sensitive adhesive layer to the stainless steel plate measured at 25°C at a peeling angle of 180° and a peeling speed of 300 mm / min.

4. The expansion band according to claim 3, wherein: The first adhesive force is greater than 1.2 N / 25 mm.

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