JP2018206885A - Adhesive tape - Google Patents

Abstract

To provide an adhesive tape capable of making a semiconductor device that is formed on a substrate, lightweight and thin by easily releasing the semiconductor device from the substrate.SOLUTION: When obtaining a semiconductor device in which multiple semiconductor elements are laminated in a thickness direction and the semiconductor elements are electrically connected with each other via a through-electrode, an adhesive tape is used while being temporarily fixed to the semiconductor device, and meets requirements A and B. The requirement A indicates that the adhesive tape pushes a silicon chip from a side face at 25°C and under 600 μm/s, and a die share strength that is measured between transparent glass and the silicon chip becomes 20 N or higher. The requirement B indicates that the adhesive tape is compliant to JIS G3469, the adhesive tape is stuck onto the silicon chip and next, after heating at 200°C for two hours and then cooling, a peel strength that is measured when the adhesive tape is peeled in a direction of 90° at 25°C while taking one end thereof, becomes 0.4 N/mm or lower.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an adhesive tape used in obtaining a semiconductor device in which a plurality of semiconductor elements are stacked in the thickness direction, and these semiconductor elements are electrically connected via a through electrode penetrating in the thickness direction. .

  In response to the recent increase in functionality of electronic devices and expansion to mobile applications, there is an increasing demand for higher density and higher integration of semiconductor devices, and IC packages are increasing in capacity and density.

  This semiconductor device is a Through Silicon Via (TSV) type in which a plurality of semiconductor elements are stacked in the thickness direction, and these semiconductor elements are electrically connected via a through electrode penetrating in the thickness direction. Has been proposed (see, for example, Patent Document 1).

  In such a method for manufacturing a semiconductor device, first, a semiconductor element is stacked on a substrate so that an electrode pad included in the semiconductor element is on the upper side, and then the semiconductor element is further stacked on the semiconductor element in the same manner.

  Thereafter, a through electrode penetrating in the thickness direction is formed in the upper semiconductor element so that the electrode pads provided in the stacked semiconductor elements are electrically connected to each other.

  Next, the semiconductor device having the above-described structure is formed on the substrate by repeatedly performing the above-described stacking of further semiconductor elements with respect to the semiconductor elements and electrical connection between the electrode pads by forming through electrodes. Manufactured.

  And, with the substrate side of this semiconductor device as the upper side (face-down state), by electrically connecting the terminals provided in the wiring board and the electrode pads provided in the semiconductor element located on the opposite side of the substrate of the semiconductor device, A semiconductor device is mounted on the wiring board.

  Although the semiconductor device can be manufactured as described above, such a manufacturing method has a problem that the substrate remains in the semiconductor device, and the semiconductor device cannot be reduced in weight and thickness.

JP 2013-179135 A

  Therefore, development of an adhesive tape capable of forming an easily peelable adhesive layer between the substrate and the semiconductor device is required so that the semiconductor device formed on the substrate can be easily peeled from the substrate. It has been.

  Accordingly, an object of the present invention is to provide a pressure-sensitive adhesive tape that can easily peel off a semiconductor device formed on a substrate from the substrate and realize reduction in weight and thickness of the semiconductor device.

Such an object is achieved by the present invention described in the following (1) to (9).
(1) When obtaining a semiconductor device in which a plurality of semiconductor elements are stacked in the thickness direction and the semiconductor elements are electrically connected via a through electrode penetrating in the thickness direction, An adhesive tape that is temporarily fixed and used.
An adhesive tape characterized by satisfying both the following requirement A and the following requirement B.
Requirement A: For the adhesive tape, the adhesive tape is pasted on transparent glass, and then a 10 × 10 mm silicon chip is fixed to the transparent glass via the adhesive tape, and then 600 μm / s at 25 ° C. The die shear strength measured when the silicon chip is pushed from the side surface and a breakage occurs between the transparent glass and the silicon chip is 20 N or more.
Requirement B: In accordance with JIS G 3469, the adhesive tape is affixed with a 25 mm wide adhesive tape on a plate-shaped silicon chip, then heated at 200 ° C. for 2 hours and cooled. The peel strength measured when holding one end of the adhesive tape and peeling it off at 25 ° C. in the direction of 90 ° at a speed of 300 mm / min is 0.4 N / mm or less.

  (2) The said adhesive tape is an adhesive tape as described in said (1) whose hot melt viscosity measured by a rheometer at 150 degreeC is 500 Pa.s or more and 3500 Pa.s or less.

  (3) The said adhesive tape is an adhesive tape as described in said (1) or (2) whose breaking strength in 20 degreeC is 10 Mpa or more and 100 Mpa or less.

  (4) The said adhesive tape is an adhesive tape in any one of said (1) thru | or (3) whose breaking elongation in 20 degreeC is 10% or more and 2000% or less.

  (5) The said adhesive tape is an adhesive tape in any one of said (1) thru | or (4) whose weight decreasing rate in 340 degreeC is 0.001% or less.

  (6) The said adhesive tape is an adhesive tape in any one of said (1) thru | or (5) which contains a styrene block copolymer as a main material.

  (7) The styrenic block copolymer is a block copolymer comprising a first block obtained by polymerizing styrene and a second block obtained by polymerizing at least one of ethylene, propylene and butylene. The adhesive tape as described in (6).

  (8) In the styrenic block copolymer, the second block includes a polymer of ethylene and propylene, and includes a first block, the second block, and the first block in this order. The pressure-sensitive adhesive tape according to (7), which is a block copolymer.

  (9) The said adhesive tape is an adhesive tape in any one of said (1) thru | or (8) whose thickness is 10 micrometers or more and 300 micrometers or less.

  According to the pressure-sensitive adhesive tape of the present invention, the semiconductor device is formed on the substrate with the pressure-sensitive adhesive layer derived from the pressure-sensitive adhesive tape interposed therebetween, whereby the semiconductor device can be easily removed from the substrate after the semiconductor device is formed. Therefore, the formed semiconductor device can be reduced in weight and thickness.

It is a longitudinal cross-sectional view which shows an example of the semiconductor device manufactured using the adhesive tape of this invention. It is a longitudinal cross-sectional view for demonstrating the manufacturing method of the semiconductor device which manufactures multiple semiconductor devices collectively using the adhesive tape of this invention. It is a longitudinal cross-sectional view for demonstrating the manufacturing method of the semiconductor device which manufactures multiple semiconductor devices collectively using the adhesive tape of this invention. It is a longitudinal cross-sectional view for demonstrating the manufacturing method of the semiconductor device which manufactures multiple semiconductor devices collectively using the adhesive tape of this invention.

Hereinafter, the adhesive tape of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
First, prior to describing the adhesive tape of the present invention, a semiconductor device manufactured using the adhesive tape of the present invention will be described.

<Semiconductor device>
FIG. 1 is a longitudinal sectional view showing an example of a semiconductor device manufactured using the adhesive tape of the present invention. In the following description, the upper side in FIG. 1 is referred to as “upper” and the lower side is referred to as “lower”.

  The semiconductor device 20 is a Through Silicon Via (TSV) type semiconductor device, which is a kind of Cip on Cip (COC) type semiconductor device. As shown in FIG. 1, a plurality of stacked (four in this embodiment) are stacked. ) Semiconductor element 26, a bonding layer 27 that bonds semiconductor elements 26 adjacent in the thickness direction, and a through electrode 23 that electrically connects these semiconductor elements 26 to each other. The plurality of semiconductor elements 26 are stacked via the bonding layer 27 with the main surface including the semiconductor integrated circuit facing upward (in the same direction), and the electrode pads 25 provided on the main surfaces of the semiconductor elements 26 adjacent in the thickness direction. Are electrically connected through the through electrode 23.

  In the semiconductor device 20, the semiconductor element 26 has a semiconductor integrated circuit (not shown) on the upper surface side which is the main surface, and further has electrode pads 25 electrically connected to the semiconductor integrated circuit on the upper surface. doing.

  The electrode pad 25 is formed on the upper surface of the semiconductor integrated circuit via an insulating layer (not shown), and is electrically connected to wiring provided in the semiconductor integrated circuit.

  The semiconductor elements 26 adjacent in the thickness direction (vertical direction) are bonded to each other through a bonding layer 27 having an insulating property, and the electrode pads 25 included in each semiconductor element 26 are connected to each other. It is electrically connected through a through electrode 23 provided so as to penetrate.

  The semiconductor device 20 configured as described above can be manufactured by using the adhesive tape of the present invention.

<Method for Manufacturing Semiconductor Device>
Hereafter, the manufacturing method of the semiconductor device 20 using the adhesive tape of this invention is explained in full detail.

  In the method for manufacturing the semiconductor device 20, a preparation step for preparing (preparing) the semiconductor wafer 200, a pasting step for pasting the adhesive tape 102 to the semiconductor wafer 200, and a semi-curing process on the opposite side of the adhesive tape 102 of the semiconductor wafer 200. A bonding layer forming step for forming the bonding layer 27 in a state, a bonding step for bonding the semiconductor wafers 200 through the cured bonding layer 27, an electrode pad 25 provided in the semiconductor wafer 200 located on the lower side, A through electrode forming step of electrically connecting the electrode pad 25 included in the semiconductor wafer 200 positioned on the upper side through the through electrode 23, and further bonding the semiconductor wafer 200 on the semiconductor wafer 200 through the bonding layer 27. And a dicing tape through an adhesive tape 102 to a laminate in which a plurality of semiconductor wafers 200 are laminated Bonding step for bonding 01, separation step for separating the laminated semiconductor wafers 200 at positions corresponding to each semiconductor element 26, and separation step for peeling (removing) the semiconductor device 20 from the adhesive tape 102 And have.

  2 to 4 are vertical cross-sectional views for explaining a method of manufacturing a semiconductor device in which a plurality of semiconductor devices are manufactured at once using the adhesive tape of the present invention. In the following description, the upper side in FIGS. 2 to 4 is referred to as “upper” and the lower side is referred to as “lower”.

  [1] First, a semiconductor wafer 200 (semiconductor substrate) having a plurality of semiconductor elements 26 (semiconductor chips) formed with semiconductor integrated circuits on the upper surface is prepared (prepared) (see FIG. 2A).

  [2] Next, as shown in FIG. 2B, an adhesive tape 102 (adhesive tape of the present invention) is prepared, and the semiconductor wafer 200 has this adhesive tape 102 on a semiconductor wafer 200 (semiconductor substrate). Arrangement (sticking) is performed so that the electrode pad 25 is opposite to the adhesive tape 102 (sticking step).

  The adhesive tape 102 alone supports the semiconductor wafer 200 in the present step [2] to the subsequent step [6], and the semiconductor wafer 200 (semiconductor element 26) in the subsequent step [7] to the subsequent step [8]. In the subsequent step [9], the semiconductor element 26 is bonded to the semiconductor element 26 with such a strength that the separated semiconductor element 26 can be peeled off.

  The pressure-sensitive adhesive tape 102 is composed of the pressure-sensitive adhesive tape of the present invention, and satisfies both the following requirement A and the following requirement B.

  Requirement A: Adhesive tape is affixed on transparent glass, then a 10 × 10 mm silicon chip is fixed to the transparent glass via the adhesive tape, and then the side of the silicon chip is 600 μm / s at 25 ° C. And the die shear strength (shear strength) measured when a breakage occurs between the transparent glass and the silicon chip is 20 N or more.

  Requirement B: In accordance with JIS G 3469, the pressure-sensitive adhesive tape is affixed with a 25 mm wide adhesive tape on a plate-shaped silicon chip, then heated at 200 ° C. for 2 hours and cooled, The peel strength measured when the adhesive tape is held at one end and peeled off at 25 ° C. in the direction of 90 ° at a speed of 300 mm / min is 0.4 N / mm or less.

  Here, when the surface direction of the adhesive tape 102 is the X, Y direction and the thickness direction of the adhesive tape 102 is the Z direction, satisfying the requirement A, that is, the die shear strength is 20 N or more, It can be said that the shearing force in the X and Y directions and the adhesive force are excellent. Therefore, when the semiconductor wafer 200 is further stacked on the semiconductor wafer 200 in the post-process [4], when the through electrode 23 is formed on the semiconductor wafer 200 in the post-process [5], and in the post-process [8]. In the formation of the semiconductor element 26 by dividing the semiconductor wafer 200 into pieces, the semiconductor wafer 200 (semiconductor element 26) is accurately suppressed or prevented from being displaced from the adhesive tape 102 and further separated. Therefore, the semiconductor wafer 200 (semiconductor element 26) can be reliably held on the adhesive tape 102.

  In addition, the heat treatment was performed by satisfying the requirement B, that is, when the peel strength with respect to the silicon chip after heating and cooling at 200 ° C. for 2 hours was 0.4 N / mm or less. Even after this, the adhesive force of the adhesive tape 102 to the semiconductor element 26 in the Z direction is low. Therefore, when the adhesive tape 102 is peeled from the semiconductor element 26 in the post-process [9], the adhesive tape 102 can be reliably peeled from the semiconductor element 26 without leaving the adhesive tape 102 on the semiconductor element 26. .

  The die shear strength of the requirement A can be measured using, for example, a universal bond tester (manufactured by DAGE, “Series 4000”), and the peel strength of the requirement B is, for example, a tensile tester. (A & D, “TENSILON RTG-1310”) can be used.

  The pressure-sensitive adhesive tape 102 having the above-described function, that is, the pressure-sensitive adhesive tape 102 satisfying the requirement A and the requirement B is composed mainly of a styrene block copolymer that is a rubber-based pressure-sensitive adhesive.

  The styrene block copolymer is not particularly limited. For example, styrene / butadiene rubber (SB), styrene / isoprene rubber (SI), propylene / butylene / styrene block copolymer (PBS), styrene / isoprene / Styrene block copolymer (SIS), styrene / butadiene / styrene block copolymer (SBS), styrene / ethylene / butylene / styrene block copolymer (SEBS), styrene / ethylene / propylene / styrene block copolymer (SEPS) ), Styrene / ethylene / ethylene / propylene / styrene block copolymer (SEEPS), styrene / ethylene / propylene block copolymer (SEP), styrene / ethylene / propylene block copolymer (SEP), and the like. of It can be used in combination of at least Chino one or.

  The styrenic block copolymer preferably includes a first block obtained by polymerizing styrene and a second block obtained by polymerizing at least one of ethylene, propylene and butylene. The second block may be a block formed by polymerizing at least one hydrogenated product of ethylene, propylene, and butylene. Moreover, the 1st block should just be a block which used styrene as the main structural component, and may contain other components, such as ethylene.

  Further, the second block preferably has a block containing a polymer of ethylene and propylene. Thereby, the adhesive tape can surely satisfy the requirement A and the requirement B. The second block may be composed of a block copolymer including an ethylene block (subblock) and a butylene block (subblock), or a random copolymer of ethylene and butylene. May be.

  Furthermore, the styrenic block copolymer is preferably a triblock copolymer comprising a first block, a second block, and a first block in this order. Thereby, the adhesive tape can surely satisfy the requirement A and the requirement B. The second block may be composed of two or more random copolymers of ethylene, propylene and butylene, or may be composed of two or more block copolymers of ethylene, propylene and butylene. Good. Even in the case where the second block has such a configuration, in the present specification, the styrenic block copolymer is the triblock copolymer.

  Specifically, as the styrenic block copolymer having the first block and the second block, for example, a styrene-hydrogenated isoprene diblock copolymer (SEP) represented by the following general formula (A): Styrene-hydrogenated isoprene-styrene triblock copolymer (SEPS) represented by the following general formula (B), styrene- (ethylene / butylene) -styrene triblock represented by the following general formula (C) Copolymer (SEBS), styrene- (hydrogenated isoprene / ethylene) -styrene triblock copolymer (SEEPS-OH) represented by the following general formula (D), and the like are considered. Thus, it is preferable to contain SEPS represented by the following general formula (B).

［式中、ｍ、ｐは、１以上の整数を表し、その大きさは、スチレン系ブロック共重合体の分子量およびスチレンの含有率により決定される。］

[Wherein, m and p represent an integer of 1 or more, and the size is determined by the molecular weight of the styrenic block copolymer and the content of styrene. ]

［式中、ｍ、ｐ、ｑは、１以上の整数を表し、その大きさは、スチレン系ブロック共重合体の分子量およびスチレンの含有率により決定される。］

[Wherein, m, p, q represent an integer of 1 or more, and the size thereof is determined by the molecular weight of the styrenic block copolymer and the content of styrene. ]

［式中、ｍ、ｎ、ｐ、ｑは、１以上の整数を表し、その大きさは、スチレン系ブロック共重合体の分子量およびスチレンの含有率により決定される。］

[Wherein, m, n, p, q represent an integer of 1 or more, and the size thereof is determined by the molecular weight of the styrenic block copolymer and the content of styrene. ]

［式中、ｍ、ｎ、ｐ、ｑは、１以上の整数を表し、その大きさは、スチレン系ブロック共重合体の分子量およびスチレンの含有率により決定される。］

[Wherein, m, n, p, q represent an integer of 1 or more, and the size thereof is determined by the molecular weight of the styrenic block copolymer and the content of styrene. ]

  Moreover, when the styrene block copolymer having the first block and the second block contains SEPS represented by the general formula (B), as the styrene block copolymer, It is preferable to contain SEP represented by the said general formula (A). Thus, the adhesive tape can satisfy the requirement A and the requirement B more reliably by containing both the SEP and SEPS in the styrenic block copolymer.

  Further, the weight average molecular weight (Mw) of the styrenic block copolymer is preferably 5000 or more and 1500,000 or less, and more preferably 40000 or more and 700,000 or less. In addition, a weight average molecular weight (Mw) can be obtained by preparing a calibration curve regarding a polystyrene standard substance using a gel permeation chromatography (GPC) measurement method, and calculating using this calibration curve.

  Furthermore, the content of styrene in the styrenic block copolymer is preferably 20% by mass or more and 80% by mass or less, and preferably 30% by mass or more and 70% by mass or less with respect to the total amount of the styrenic block copolymer. More preferably.

  By setting the weight average molecular weight (Mw) of the styrenic block copolymer and the content of the styrene within the above ranges, the pressure-sensitive adhesive tape more reliably satisfies the requirements A and B. it can.

  Furthermore, the adhesive tape 102 may contain an arbitrary additive as required in addition to the styrene block copolymer.

  Examples of the additive include a crosslinking agent, a rosin tackifier, a terpene tackifier, a tackifier such as a hydrocarbon tackifier, a trimellitic ester plasticizer, and a pyromellitic ester plastic. Plasticizers such as agents, pigments, dyes, fillers, anti-aging agents, conductive materials, antistatic agents, UV absorbers, light stabilizers, release modifiers, softeners, surfactants, flame retardants, antioxidants These can be used, and one or more of these can be used in combination.

  Examples of the crosslinking agent include isocyanate crosslinking agents, epoxy crosslinking agents, melamine crosslinking agents, peroxide crosslinking agents, urea crosslinking agents, metal alkoxide crosslinking agents, metal chelate crosslinking agents, metal salts. Examples thereof include a system crosslinking agent, a carbodiimide crosslinking agent, an oxazoline crosslinking agent, an aziridine crosslinking agent, and an amine crosslinking agent.

  The surfactant is not particularly limited, and examples thereof include nonionic (nonionic) surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants.

  Nonionic (nonionic) surfactants include, for example, silicones such as polyether-modified silicone, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, fatty acid monoglycerides, polyoxyalkylene fatty acid esters, and the like. Can be mentioned. Examples of the anionic surfactant include higher fatty acid salts, higher alcohol sulfate esters, alkylbenzene sulfonates, alkyl naphthalene sulfonates, and the like. Furthermore, examples of the cationic surfactant include aliphatic amine salts, quaternary ammonium salts, alkylpyridinium salts, and the like. Examples of amphoteric surfactants include various betaines such as carboxybetaine and sulfobetaine, various aminocarboxylic acids, and various phosphate esters.

  Among these, the surfactant is preferably a nonionic (nonionic) surfactant, particularly a polyether-modified silicone. Thus, by containing a surfactant (particularly, polyether-modified silicone), the pressure-sensitive adhesive tape more reliably satisfies the requirement B, that is, the peel strength is within a more preferable range. Can be set to

  Further, the content of the surfactant in the adhesive tape is preferably 0.1% by mass or more and 2.0% by mass or less, and more preferably 0.5% by mass or more and 1.0% by mass or less. . Thereby, the effect acquired by adding surfactant can be exhibited reliably.

  The adhesive tape 102 may have a die shear strength of the requirement A of 20N or more, preferably 30N or more and 300N or less, more preferably 100N or more and 250N or less, and further, the requirement B of the requirement B The peel strength may be 0.4 N / mm or less, preferably 0.001 N / mm or more and 0.04 N / mm or less, and more preferably 0.001 N / mm or more and 0.01 N / mm or less. More preferred. Thereby, in the post-process [4], the post-process [5], and the post-process [8], the function as the adhesive tape 102 that supports the semiconductor wafer 200 (semiconductor element 26) can be more reliably exhibited. In the post-process [9], the adhesive tape 102 can be more reliably peeled from the semiconductor element 26.

Furthermore, when the die shear strength of the requirement A is a [N] and the peel strength of the requirement B is b [N / mm], b / a [/ mm] is 0.02 × 10 ³ or more. It is preferably 0 × 10 ³ or less, and more preferably 0.02 × 10 ³ or more and 0.1 × 10 ³ or less. Thereby, the effect acquired by satisfying the requirements A and B can be exhibited more notably.

  The adhesive tape 102 preferably has a hot melt viscosity (ηPa · s) measured by a rheometer at 150 ° C. of 500 Pa · s to 3500 Pa · s, preferably 1500 Pa · s to 3000 Pa · s. It is more preferable. The hot melt viscosity can be measured using, for example, a rotary viscometer (manufactured by Thermo Fisher Scientific, “HAAKE MARSIII”).

  Furthermore, the adhesive tape preferably has a breaking strength at 20 ° C. of 10 MPa to 100 MPa, and more preferably 30 MPa to 50 MPa. The adhesive tape preferably has a breaking elongation at 20 ° C. of 10% or more and 2000% or less, and more preferably 500% or more and 900% or less. The breaking strength and breaking elongation can be measured using, for example, a tensile tester (manufactured by A & D, “TENSILON RTG-1310”).

  When the viscosity, breaking strength and breaking elongation of the adhesive tape 102 are within the above ranges, the semiconductor wafer 200 (semiconductor element 26) is supported in the post-process [4], post-process [5] and post-process [8]. It is possible to accurately suppress or prevent occurrence of thickness unevenness or breakage in the adhesive tape 102. Therefore, the semiconductor wafer 200 (semiconductor element 26) can be stably bonded by the adhesive tape 102.

  Furthermore, the pressure-sensitive adhesive tape preferably has a weight reduction rate at 340 ° C. of 0.001% or less. Accordingly, even when the semiconductor wafers 200 are bonded to each other via the bonding layer 27 in the post-process [4], even if the bonding layer 27 is heated to be cured, the adhesive tape 102 is deteriorated and deteriorated by this heating. Can be accurately suppressed or prevented. Therefore, even after the post-process [4], the pressure-sensitive adhesive tape 102 that satisfies the requirements A and B can be obtained, and the function as the pressure-sensitive adhesive tape 102 can be reliably exhibited. Furthermore, since the outgas generation due to the pressure-sensitive adhesive tape 102 is accurately suppressed during this heating, it is possible to accurately suppress the adhesion of the residue derived from the pressure-sensitive adhesive tape 102 to the manufactured semiconductor device 20. it can.

  The weight loss rate of the adhesive tape at 340 ° C. was measured using a TG / DTA measuring device (“TG / DTA220” manufactured by Seiko Instruments Inc.) under a nitrogen gas flow of 200 mL / min and a heating rate of 10 ° C./min. The temperature was raised to 340 ° C. depending on the conditions, and the weight of the adhesive tape at this time was measured to calculate based on the weight of the adhesive tape before and after heating.

  Moreover, the thickness of the adhesive tape 102 is not particularly limited, but is preferably, for example, 10 μm or more and 300 μm or less, more preferably 30 μm or more and 200 μm or less, and further preferably 40 μm or more and 150 μm or less. By setting the thickness of the pressure-sensitive adhesive tape 102 within such a range, the pressure-sensitive adhesive tape 102 exhibits good adhesive force in the post-process [4], the post-process [5], and the post-process [8], and the post-process. In [9], good peelability is exhibited between the adhesive tape 102 and the semiconductor device 20.

  The adhesive tape 102 as described above is affixed to the semiconductor wafer 200. When the adhesive tape 102 prior to application is stored and transported, it is preferable that separators are laminated on both surfaces (surfaces). Thereby, it is possible to accurately prevent the surface of the adhesive tape 102 from being contaminated when the adhesive tape 102 (the adhesive tape of the present invention) is stored and transported.

  In addition, although it does not specifically limit as a separator, A polypropylene film, a polyethylene film, a polyethylene terephthalate film etc. are mentioned.

  When the separators are stacked, the adhesive tape 102 is attached to the semiconductor wafer 200 by attaching the adhesive tape 102 to the semiconductor wafer 200 with one separator removed, and then removing the other separator. Through the process, the adhesive tape 102 can be uniformly attached to the semiconductor wafer 200 without interposing bubbles between the adhesive tape 102 and the semiconductor wafer 200.

  [3] Next, as shown in FIG. 2C, a semi-cured bonding layer 27 is formed on the opposite side of the semiconductor wafer 200 from the adhesive tape 102, that is, on the surface side where the electrode pads 25 are formed. Form (bonding layer forming step).

  That is, with the semiconductor wafer 200 fixed on the adhesive tape 102, the semi-cured bonding layer 27 is formed on the surface of the semiconductor wafer 200 where the electrode pads 25 are formed.

  For example, the bonding layer 27 is supplied onto the semiconductor wafer 200 by using a liquid phase film formation method such as a spin coating method, and then, for example, at a temperature lower than that at 200 ° C. for 2 hours and under a short time condition. By heating, a semi-cured state is formed. The bonding layer 27 may be in a semi-cured state, may be formed using a vapor phase film forming method instead of the liquid phase film forming method, or may be a semi-cured film. The bonding layer 27 in a state may be formed by directly attaching to the semiconductor wafer 200.

  The constituent material of the bonding layer 27 is not particularly limited as long as it is a thermosetting resin material, and examples thereof include epoxy resins, acrylic resins, and polyimide resins.

  [4] Next, as shown in FIG. 2 (d), the process is performed on the semiconductor wafer 200 fixed in the adhesive tape 102 obtained in the process [3] and having the bonding layer 27 formed thereon. The same semiconductor wafer 200 as prepared in [1] is placed (placed) so that the electrode pads 25 of the newly prepared semiconductor wafer 200 are on the upper side.

  Thereafter, in a state where the semiconductor wafers 200 are pressed so as to approach each other, for example, by performing a heat treatment that is heated at 200 ° C. for 2 hours, the semi-cured bonding layer 27 is cured to be cured. The semiconductor wafers 200 are bonded to each other through the bonded layer 27 (bonding step).

  Here, in this invention, the adhesive tape 102 satisfies the requirement A mentioned above. That is, the die shear strength measured when the silicon chip is pushed from the side surface at 25 ° C. at 600 μm / s and breakage occurs between the transparent glass and the silicon chip is 20 N or more. Therefore, in this step [4], the semiconductor wafers 200 can be bonded to each other with the semiconductor wafers 200 securely held on the adhesive tape 102 without being displaced in the adhesive tape 102.

  [5] Next, as shown in FIG. 3A, in the stacked body in which the semiconductor wafers 200 are bonded to each other via the bonding layer 27, the semiconductor wafer 200 is positioned on the lower side, which is disposed at an overlapping position in the thickness direction. The electrode pad 25 included in the semiconductor wafer 200 and the electrode pad 25 included in the semiconductor wafer 200 located on the upper side are electrically connected via the through electrode 23 (through electrode forming step).

  Thereby, the laminated body of the semiconductor wafer 200, the bonding layer 27, and the semiconductor wafer 200 in which the electrode pads arranged at the overlapping positions in the thickness direction are electrically connected via the through electrode 23 is formed on the adhesive tape 102. Obtained on the upper side.

  The through electrode 23 is formed, for example, in a photolithography method in a region where the electrode pad 25 included in the lower semiconductor wafer 200 and the electrode pad 25 included in the upper semiconductor wafer 200 overlap in the thickness direction. In addition, by combining various etching methods and the like, a part of the electrode pad 25 included in the semiconductor wafer 200 located on the upper side and a part of the semiconductor wafer 200 located on the lower side of the electrode pad 25 are removed to form a via hole. Thereafter, the through electrode 23 can be formed in the via hole by using various plating methods such as an electroless plating method and an electrolytic plating method.

  Also in this step [5], since the adhesive tape 102 satisfies the requirement A described above, the semiconductor wafers 200 are securely held on the adhesive tape 102 without being displaced in the adhesive tape 102. Thus, the electrode pads 25 included in the upper and lower semiconductor wafers 200 can be electrically joined via the through electrode 23.

  [6] Next, with respect to the laminated body of the semiconductor wafer 200, the bonding layer 27, and the semiconductor wafer 200 provided on the adhesive tape 102 and including the through electrode 23 obtained in the step [5], By repeating step [3] to step [5], the semiconductor wafer 200 is further bonded onto the semiconductor wafer 200 via the bonding layer 27 (repeating step).

  In the present embodiment, the steps [3] to [5] are repeated twice in total. Thereby, as shown in FIG. 3B, two semiconductor wafers 200 are further formed in the thickness direction via the bonding layer 27 with respect to the stacked body of the semiconductor wafer 200, the bonding layer 27, and the semiconductor wafer 200. Laminated.

  As a result, three semiconductor wafers 200 are further stacked in the thickness direction via the bonding layer 27 on the semiconductor wafer 200, and the electrode pads 25 corresponding to the overlapping positions in the thickness direction form the through electrodes 23. A laminated body electrically connected through the adhesive tape 102 is obtained on the upper side of the adhesive tape 102.

  [7] Next, as shown in FIG. 3 (c), a dicing tape 101 is prepared, and the adhesive tape 102 is applied to the laminated body in which the plurality of semiconductor wafers 200 obtained in the step [6] are laminated. Then, the dicing tape 101 is bonded (bonding process).

  The dicing tape 101 includes a base material layer and an adhesive layer laminated on the base material layer and bonded to the adhesive tape 102. In the next step [8], a laminated body in which a plurality of semiconductor wafers 200 are laminated. When this is separated into pieces using a dicing saw, it has a function of supporting the laminated body via the adhesive tape 102.

  As the base material layer, a material composed mainly of a resin material is preferably used. Examples of the resin material include polyolefin resins such as polyvinyl chloride, polyethylene, polypropylene, polybutene, polybutadiene, and polymethylpentene, ethylene / vinyl acetate copolymer, ionomer, and ethylene / (meth) acrylic acid copolymer. , Olefin copolymers such as ethylene / (meth) acrylic acid ester copolymers, polyalkylene terephthalate resins such as polyethylene terephthalate and polybutylene terephthalate, styrene thermoplastic elastomers, olefin thermoplastic elastomers, polyvinyl isoprene, polycarbonate These can be used, and one or more of these can be used in combination.

  As the adhesive layer, acrylic resin (adhesive), silicone resin (adhesive), polyester resin (adhesive), polyvinyl acetate resin (adhesive), polyvinyl ether resin (adhesive), Those composed mainly of an adhesive layer component such as a styrene elastomer resin (adhesive), polyisoprene resin (adhesive), polyisobutylene resin (adhesive) or urethane resin (adhesive) are preferred. Used.

  [8] Next, as shown in FIG. 4A, each semiconductor element 26 is handled in a state in which a laminated body in which a plurality of semiconductor wafers 200 are laminated is supported by a dicing tape 101 via an adhesive tape 102. The stacked semiconductor wafers 200 are separated into individual pieces at a position where they are to be separated (separation step).

  As a result, a plurality of semiconductor devices 20 can be collectively obtained on the upper side of the dicing tape 101 via the adhesive tape 102.

  For example, the semiconductor wafer 200 is separated into individual pieces at a position corresponding to each semiconductor element 26 of the semiconductor wafer 200 using a dicing saw in the thickness direction of the stacked body in which a plurality of semiconductor wafers 200 are stacked. This can be done by cutting the semiconductor wafer 200 to a position reaching the tape 102.

  Also in this step [8], since the pressure-sensitive adhesive tape 102 satisfies the requirement A described above, the laminated body in which the semiconductor wafers 200 are laminated is not displaced on the pressure-sensitive adhesive tape 102 and the adhesive tape 102 is not displaced. The semiconductor wafer 200 can be separated into pieces while being securely held, and a plurality of semiconductor devices 20 can be formed on the adhesive tape 102.

  [9] Next, the semiconductor device 20 adhered to the adhesive tape 102 on the dicing tape 101 is pushed up using a needle or the like, and in this state, by suction using a vacuum collet or air tweezers, FIG. ) And FIG. 4C, the semiconductor device 20 is peeled off (removed) from the adhesive tape 102 by sequentially picking up (peeling step).

  As a result, a plurality of semiconductor devices 20 can be obtained collectively from a stacked body in which a plurality of semiconductor wafers 200 are stacked. Furthermore, the semiconductor device 20 can be obtained in a state where the substrate such as the dicing tape 101 is peeled off without remaining. For this reason, the obtained semiconductor device 20 can be reduced in weight and thickness.

  Moreover, in this invention, the adhesive tape 102 satisfies the requirement B mentioned above. That is, after heating at 200 ° C. for 2 hours and cooling, the peel strength measured when holding one end of the adhesive tape and peeling at 25 ° C. in the direction of 90 ° at a speed of 300 mm / min is 0. 4 N / mm or less. Therefore, even if the adhesive tape 102 has undergone a thermal history due to the heat treatment in the step [4], the adhesive tape 102 can be easily peeled from the semiconductor device 20 in the present step [9].

  Through the above-described steps, a semiconductor in which a plurality of semiconductor elements 26 are stacked in the thickness direction and the semiconductor elements 26 are electrically connected via a through electrode 23 penetrating in the thickness direction. A plurality of devices 20 are manufactured.

  According to such a manufacturing method of the semiconductor device 20, the plurality of semiconductor elements 26 are stacked in the thickness direction, and the semiconductor elements 26 are electrically connected to each other through the through electrode 23 that penetrates in the thickness direction. By using the adhesive tape 102 (the adhesive tape of the present invention), the semiconductor device 20 can be manufactured in a lump. In addition, since the semiconductor device 20 is temporarily fixed to the pressure-sensitive adhesive tape 102 (the pressure-sensitive adhesive tape of the present invention) and the semiconductor device 20 can be formed without being fixed to the substrate, the weight of the semiconductor device 20 can be reduced. Further, the thickness may be reduced.

  The semiconductor device 20 manufactured using the adhesive tape of the present invention includes, for example, a mobile phone, a digital camera, a video camera, a car navigation system, a personal computer, a game machine, a liquid crystal television, a liquid crystal display, an organic electroluminescence display, and a printer. Can be used widely.

  The adhesive tape of the present invention has been described above, but the present invention is not limited to these.

  For example, the pressure-sensitive adhesive tape of the present invention may be added with any component that can exhibit the same function, or may be a laminate of two or more layers in addition to the one constituted of the single layer described above. It may be configured.

Next, specific examples of the present invention will be described.
In addition, this invention is not limited to description of these Examples at all.

1. Preparation of raw materials First, the raw materials used for the production of the adhesive tapes of Examples and Comparative Examples are as follows.

<Styrenic block copolymer>
SEP represented by the above general formula (A) (Kuraray, “Septon 2002”)
SEPS represented by the above general formula (B) (Kuraray Co., Ltd., “Septon 2004”)
SEBS represented by the above general formula (C) (Kuraray, "Septon 8007")
SEEPS-OH represented by the above general formula (D) (Kuraray, “Septon 8004”)
SIS ("JSR SIS5250" manufactured by JSR Corporation)

<Other polymers>
Polypropylene (PP; manufactured by Sumitomo Chemical Co., Ltd., “FS2011DG3”)

<Surfactant>
Polyether-modified polydimethylsiloxane (Bick Chemie, “BKY-333”)

2. Preparation of adhesive tape forming material (Sample No. 1)
The SEP represented by the general formula (A) is 64.8% by mass, the SEEPS-OH represented by the general formula (D) is 2.0% by mass, and the SEBS represented by the general formula (C) is After weighing each so as to be 33.2% by mass, the sample is dissolved in methylene so that the content of these constituent materials is 25% by mass. 1 adhesive tape forming material was prepared.

(Sample No. 2)
As constituent materials, SEP represented by the general formula (A) is 64.4% by mass, SEEPS-OH represented by the general formula (D) is 2.0% by mass, and represented by the general formula (C). The sample No. 1 was measured except that the SEBS was 33.0% by mass and the surfactant was 0.6% by mass. In the same manner as in sample 1, sample no. 2 adhesive tape forming materials were prepared.

(Sample No. 3)
As constituent materials, SEP represented by the general formula (A) is 64.3% by mass, SEEPS-OH represented by the general formula (D) is 2.0% by mass, and represented by the general formula (C). The sample No. 1 was measured except that the SEBS was 32.9 mass% and the surfactant was 0.8 mass%. In the same manner as in sample 1, sample no. 3 adhesive tape forming material was prepared.

(Sample No. 4)
Except that the SEP represented by the general formula (A) was 36.0% by mass and the SEPS represented by the general formula (B) was weighed so that the constituent materials were 64.0% by mass, respectively. Sample No. In the same manner as in sample 1, sample no. 4 adhesive tape forming material was prepared.

(Sample No. 5)
As a constituent material, SEP represented by the general formula (A) is 35.7% by mass, SEPS represented by the general formula (B) is 63.5% by mass, and the surfactant is 0.8% by mass. Except for being weighed in each case, the sample no. In the same manner as in sample 1, sample no. 5 adhesive tape forming material was prepared.

(Sample No. 6)
Except that the SIS was 40.0% by mass and the PP was 60.0% by mass, respectively, as the constituent materials, the sample no. In the same manner as in sample 1, sample no. 6 adhesive tape forming material was prepared.

3. Evaluation <Production of adhesive tape>
Each sample No. About the adhesive tape forming material, after being supplied onto a polyimide film (manufactured by Upilex, thickness 50 μm) using a spin coating method (rotation speed 250 to 300 rpm, time 10 sec), the pot plate is used at 60 ° C./30 min. By heating and drying under the conditions, each sample No. An adhesive tape was prepared.

  Each sample No. obtained as described above was obtained. Each of the adhesive tapes was measured for its film thickness using a constant pressure thickness measuring instrument (manufactured by Technoc) in accordance with JIS K 6783. The film thickness was measured using each sample No. Each of the adhesive tapes was carried out at 15 locations. The measurement results are shown in Table 1.

<Die shear strength>
Each sample No. About the adhesive tape forming material, after being supplied onto a polyimide film (manufactured by Upilex, thickness 50 μm) using a spin coating method (rotation speed 250 to 300 rpm, time 10 sec), the pot plate is used at 60 ° C./30 min. By heating and drying under the conditions, each sample No. An adhesive tape was prepared.

  And each sample No. Are attached (transferred) onto transparent glass (non-alkali glass, Corning, “EAGLE XG”), and then a 10 × 10 mm silicon chip is fixed to the transparent glass via the adhesive tape, The die shear strength measured when a silicon chip was pushed from the side surface at 25 ° C. at 600 μm / s and a break occurred between the transparent glass and the silicon chip was measured using a universal bond tester (manufactured by DAGE, “Series 4000”). ). The measurement results are shown in Table 1.

<Peel strength>
Each sample No. About the adhesive tape forming material, after being supplied onto a polyimide film (manufactured by Upilex, thickness 50 μm) using a spin coating method (rotation speed 250 to 300 rpm, time 10 sec), the pot plate is used at 60 ° C./30 min. By heating and drying under the conditions, each sample No. An adhesive tape was prepared.

  And each sample No. Each of the adhesive tapes having a width of 25 mm was pasted (transferred) onto a silicon chip (pseudo semiconductor element) molded into a plate shape, then heated at 200 ° C. for 2 hours, cooled, In accordance with JIS G 3469, the peel strength measured when the tape is peeled off at a speed of 300 mm / min in the direction of 90 ° at 25 ° C. is measured with a tensile tester (A & D). The measurement was performed using “TENSILON RTG-1310” manufactured by the company. The measurement results are shown in Table 1.

<Viscosity>
Each sample No. The adhesive tape forming material was supplied on a release PET film (manufactured by Teijin DuPont, thickness 38 μm) using a spin coating method (rotation speed 250 to 300 rpm, time 10 sec), and then 60 ° C. by a pot plate. Each sample No. on the release PET film by heating and drying under the condition of / 30 min. An adhesive tape was prepared.

  And each sample No. After peeling the adhesive tape from the release PET film, the hot melt viscosity measured by a rheometer at 150 ° C. was measured using a rotary viscometer (manufactured by Thermo Fisher Scientific, “HAAKE MARSIII”). It was measured. The measurement results are shown in Table 1.

<Breaking strength, breaking elongation>
Each sample No. The adhesive tape forming material was supplied on a release PET film (manufactured by Teijin DuPont, thickness 38 μm) using a spin coating method (rotation speed 250 to 300 rpm, time 10 sec), and then 60 ° C. by a pot plate. Each sample No. on the release PET film by heating and drying under the condition of / 30 min. An adhesive tape was prepared.

  And each sample No. The breaking strength and breaking elongation at 20 ° C. of this adhesive tape were measured using a tensile tester (manufactured by A & D, “TENSILON RTG-1310”). The measurement results are shown in Table 1.

<Weight reduction rate>
Each sample No. The adhesive tape forming material was supplied on a release PET film (manufactured by Teijin DuPont, thickness 38 μm) using a spin coating method (rotation speed 250 to 300 rpm, time 10 sec), and then 60 ° C. by a pot plate. Each sample No. on the release PET film by heating and drying under the condition of / 30 min. An adhesive tape was prepared.

  And each sample No. After peeling the adhesive tape from the release PET film, using a TG / DTA measuring device (“TG / DTA220” manufactured by Seiko Instruments Inc.), the weight reduction rate of the adhesive tape at 340 ° C. is as follows. Asked. That is, under a nitrogen gas flow of 200 mL / min, the temperature was increased to 340 ° C. under the condition of a heating rate of 10 ° C./min, the weight of the adhesive tape at this time was measured, and then the adhesion before and after the measured heating was measured. Based on the weight of the tape, the weight reduction rate of the adhesive tape at 340 ° C. was calculated. The measurement results are shown in Table 1.

<Peelability of adhesive tape from semiconductor elements>
The peelability of the adhesive tape from the semiconductor element was evaluated as follows.

  That is, first, each sample No. About the adhesive tape forming material, after being supplied onto a polyimide film (manufactured by Upilex, thickness 50 μm) using a spin coating method (rotation speed 250 to 300 rpm, time 10 sec), the pot plate is used at 60 ° C./30 min. By heating and drying under the conditions, each sample No. An adhesive tape was prepared.

  Next, each sample No. After removing the adhesive tape from the polyimide film, a flip chip bonder (manufactured by Panasonic Corporation) is used to mount a Si substrate (pseudo semiconductor element) 10 mm long × 10 mm wide × 0.7 mm thick on the adhesive tape. Thereafter, heating / compression treatment was performed under the conditions of 170 ° C./150 N / 20 sec.

  And after heating and cooling at 200 ° C. for 2 hours, the adhesive tape is peeled off from the semiconductor element, and the state of the bonding surface to which the adhesive tape of the semiconductor element was bonded at this time is confirmed. Based on the evaluation criteria shown, the peelability of the adhesive tape from the semiconductor element was evaluated. The evaluation results are shown in Table 1.

[Evaluation criteria]
The adhesive tape is completely peeled off from the bonding surface of the semiconductor element:
Peeled with some adhesive tape remaining on the bonding surface of the semiconductor element: ○
Peeled with more than half of the adhesive tape remaining on the bonding surface of the semiconductor element:
Unable to peel adhesive tape from semiconductor element: ×

<Semiconductor element misalignment in the laminate>
The deviation of the semiconductor element in the stacked body (pseudo semiconductor device) was evaluated as follows.

  <1> First, each sample No. For the adhesive tape forming material, a spin coat method (rotation speed 250 to 300 rpm, time 10 sec) is used on an FR4 substrate (a substrate formed by sealing a glass fiber cloth with a cured epoxy resin). After the supply, each sample No. was placed on the FR4 substrate by heating and drying with a pot plate at 60 ° C./30 min. An adhesive tape was prepared.

  <2> Next, each sample No. Each of the sample Nos. Formed on the adhesive tape was peeled off from the FR4 substrate. A semiconductor wafer was placed on the adhesive tape, and then heated and compressed under the conditions of 170 ° C./150 N / 20 sec.

  <3> Next, an epoxy adhesive was supplied to the upper surface of the semiconductor wafer fixed on the adhesive tape, and then a heat treatment was performed to form a semi-cured bonding layer.

  <4> Next, the semiconductor wafer fixed on the adhesive tape and having the semi-cured bonding layer formed thereon is further heated after being placed on the semiconductor wafer at 170 ° C./150 N / 20 sec.・ Compressed. Then, the laminated body in which two semiconductor wafers were laminated | stacked through the joining layer was formed on the adhesive tape by performing heat processing on 200 degreeC and 2 hours conditions, and hardening a joining layer.

  <5> Next, the step <3> and the step <4> were repeated a total of two times to form a laminate on which four semiconductor wafers were laminated on an adhesive tape.

  And the shift | offset | difference with respect to the adhesive tape of the semiconductor wafer in a laminated body was confirmed using the X-ray observation apparatus (made by an Ibit company), and it evaluated based on the evaluation criteria shown below. The evaluation results are shown in Table 1.

[Evaluation criteria]
Before and after forming the laminate
Misalignment of the semiconductor wafer is not recognized:
A slight misalignment of the semiconductor wafer is observed before and after the formation of the laminate: ○
Before and after forming the laminate
The semiconductor wafer misalignment is clearly recognized: ×

  As shown in Table 1, in each example, by satisfying both the requirements A and B, the semiconductor wafer was bonded to the adhesive tape at the time of manufacturing the laminated body (pseudo semiconductor device). The results showed that the laminate can be produced without causing the semiconductor wafer to be displaced, and the adhesive tape can be peeled from the laminate after the production of the laminate.

  On the other hand, in the comparative example, although the requirement A is satisfied but the requirement B is not satisfied, the laminated body is manufactured in the same manner as in each example without causing a semiconductor wafer shift in the laminated body. However, the adhesive tape could not be peeled from the laminate after the production of the laminate.

DESCRIPTION OF SYMBOLS 20 Semiconductor device 23 Through-electrode 25 Electrode pad 26 Semiconductor element 27 Bonding layer 101 Dicing tape 102 Adhesive tape 200 Semiconductor wafer

Claims (9)

When obtaining a semiconductor device in which a plurality of semiconductor elements are stacked in the thickness direction and the semiconductor elements are electrically connected via a through electrode penetrating in the thickness direction, the semiconductor element is temporarily fixed to the semiconductor device. Adhesive tape used,
An adhesive tape characterized by satisfying both the following requirement A and the following requirement B.
Requirement A: For the adhesive tape, the adhesive tape is pasted on transparent glass, and then a 10 × 10 mm silicon chip is fixed to the transparent glass via the adhesive tape, and then 600 μm / s at 25 ° C. The die shear strength measured when the silicon chip is pushed from the side surface and a breakage occurs between the transparent glass and the silicon chip is 20 N or more.
Requirement B: In accordance with JIS G 3469, the adhesive tape is affixed with a 25 mm wide adhesive tape on a plate-shaped silicon chip, then heated at 200 ° C. for 2 hours and cooled. The peel strength measured when holding one end of the adhesive tape and peeling it off at 25 ° C. in the direction of 90 ° at a speed of 300 mm / min is 0.4 N / mm or less.   The pressure-sensitive adhesive tape according to claim 1, wherein the pressure-sensitive adhesive tape has a hot melt viscosity of 500 Pa · s or more and 3500 Pa · s or less as measured by a rheometer at 150 ° C.   The adhesive tape according to claim 1, wherein the adhesive tape has a breaking strength at 20 ° C. of 10 MPa or more and 100 MPa or less.   The pressure-sensitive adhesive tape according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive tape has a breaking elongation at 20 ° C of 10% or more and 2000% or less.   The pressure-sensitive adhesive tape according to any one of claims 1 to 4, wherein the pressure-sensitive adhesive tape has a weight reduction rate at 340 ° C of 0.001% or less.   The said adhesive tape is an adhesive tape of any one of Claim 1 thru | or 5 which contains a styrene-type block copolymer as a main material.   7. The block copolymer comprising the first block obtained by polymerizing styrene and the second block obtained by polymerizing at least one of ethylene, propylene, and butylene. The adhesive tape as described.   In the styrenic block copolymer, the second block includes a polymer of ethylene and propylene, and the triblock copolymer includes the first block, the second block, and the first block in this order. The pressure-sensitive adhesive tape according to claim 7, which is a coalescence.   The pressure-sensitive adhesive tape according to any one of claims 1 to 8, wherein the pressure-sensitive adhesive tape has a thickness of 10 µm or more and 300 µm or less.

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