Adhesive tape

Abstract

To provide an adhesive tape capable of picking up a substrate or a component by precisely preventing or suppressing generation of static electricity in the substrate or the component when the substrate or the component is picked up in a state where the substrate or the component is stuck to the adhesive tape and then pushed up from the adhesive tape side after the adhesive tape is stretched radially. [Solution] The adhesive tape 100 comprises a base material 4 and an adhesive layer 2, and is used by temporarily fixing at least one of a substrate and a component. The base material 4 includes a resin material and a conductive material. Under conditions of 23°C and 50% RH, the adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction. When the time it takes for the charged voltage to decay to 5 [V] is X [seconds], and the adhesive tape 100 is stretched 50% in the TD direction and then forcibly charged to 5000 [V] in the TD direction, the time it takes for the charged voltage to decay to 5 [V] is Y [seconds], the adhesive tape 100 satisfies YX<1.0 second.

Description

[Technical field]

[0001] The present invention relates to an adhesive tape used for temporarily fixing at least one of a substrate and a component. [Background technology]

[0002] In response to the recent trend toward more sophisticated electronic devices and the expansion into mobile applications, there is an increasing demand for higher density and integration of semiconductor devices, and IC packages are becoming larger in capacity and higher in density.

[0003] As a method for manufacturing these semiconductor devices, for example, first, an adhesive tape is attached to a semiconductor substrate (semiconductor wafer) as a substrate, and while the periphery of the semiconductor substrate is fixed with a wafer ring, the semiconductor substrate is cut in the thickness direction in a dicing process using a dicing saw, thereby cutting and separating (dividing) the semiconductor substrate into individual semiconductor elements (semiconductor chips). Next, after an expanding process in which the adhesive tape is stretched radially using a wafer ring to form gaps between adjacent semiconductor elements, a pick-up process is performed in which the individual semiconductor elements are picked up in a state in which they are pushed up using a needle. Next, the picked-up semiconductor elements are transferred to a mounting process for mounting them on a metal lead frame or a substrate (e.g., a tape substrate, an organic hard substrate, etc.). In the mounting process, the picked-up semiconductor elements are bonded to a lead frame or a substrate via, for example, an underfill material, and then the semiconductor elements are sealed on the lead frame or substrate with a sealing part to manufacture a semiconductor device.

[0004] In recent years, various studies have been conducted on adhesive tapes (dicing tapes) used in the manufacture of such semiconductor devices (see, for example, Patent Document 1).

[0005] This adhesive tape generally has a base material (film base material) and an adhesive layer formed on the base material, and the semiconductor substrate is fixed by the adhesive layer. In the adhesive tape having such a configuration, as in the manufacturing method of the semiconductor device described above, after the dicing process of dicing the semiconductor substrate, the adhesive tape is expanded radially, and a pick-up process is performed to pick up the semiconductor elements in a state in which a gap is formed between adjacent semiconductor elements. That is, in the pick-up process after the dicing process and the expanding process, the semiconductor elements are pushed up using a needle while forming a gap between adjacent semiconductor elements, and the semiconductor elements are picked up by adsorption using a vacuum collet or air tweezers while maintaining this state.

[0006] Here, there is a problem that when adhesive tape is applied to the semiconductor wafer in the above-mentioned dicing process, when the semiconductor wafer is cut using a dicing saw, and when the semiconductor elements are picked up in the pick-up process, static electricity is generated in the semiconductor elements, and the semiconductor elements are damaged and their characteristics deteriorated due to the discharge of this static electricity in the semiconductor elements.

[0007] In order to solve such problems, i.e., to prevent the generation of static electricity in semiconductor elements, an adhesive tape has been proposed that has an antistatic film provided on a substrate (see, for example, Patent Document 2).

[0008] However, in this case, there is a problem that the antistatic function is impaired due to breakage of the antistatic film when the adhesive tape is radially stretched in the expanding step, and there is a concern that this problem may impair the effect of preventing or suppressing the generation of static electricity in semiconductor elements.

[0009] Furthermore, such problems are not limited to cases where semiconductor elements as components are obtained by cutting a semiconductor substrate (semiconductor wafer) as a substrate in the thickness direction, but also occur in cases where various substrates such as glass substrates, ceramic substrates, resin material substrates, and metal material substrates are cut (diced) in the thickness direction, and then the diced components are obtained by picking up the diced components while the adhesive tape is stretched radially. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] JP 2009-245989 A [Patent Document 2] JP 2012-248607 A Summary of the Invention [Problem to be solved by the invention]

[0011] The present invention aims to provide an adhesive tape that can accurately prevent or suppress the generation of static electricity on a substrate or component when the substrate or component is picked up in a state in which the substrate or component is stuck to the adhesive tape and then pushed up from the adhesive tape side, thereby enabling pick-up. [Means for solving the problem]

[0012] Such objectives are as follows: (11) This is achieved by the present invention described in. (1) An adhesive tape comprising a substrate and an adhesive layer laminated on one side of the substrate, the adhesive layer comprising a base resin having adhesive properties as a main material, the adhesive tape being used for temporarily fixing at least one of a substrate and a component, The substrate is It is a mixture of polypropylene and hydrogenated styrenic thermoplastic elastomer (SEBS). Resin material and 、 Permanently antistatic polymer Conductive materials and 、 Including, Under the conditions of 23°C and 50% RH, the adhesive tape is forcibly charged to 5000 [V] in the TD direction, and the time it takes for the charged voltage to decay to 5 [V] is defined as X [seconds]. When the adhesive tape is stretched 50% in the TD direction, the adhesive tape is forcibly charged to 5000 [V] in the TD direction, and the time it takes for the charged voltage to decay to 5 [V] is defined as Y [seconds]. An adhesive tape characterized in that YX < 1.0 sec. is satisfied. (2) The pressure-sensitive adhesive tape according to the above (1), wherein the time period X [seconds] is 1.0 second or less.

[0013] (3) The adhesive tape according to (1) or (2) above, in which when the adhesive tape is stretched 100% in the TD direction, the adhesive tape is forcibly charged to 5,000 [V] in the TD direction, and the time taken for the charged voltage to decay to 5 [V] is defined as Z1 [seconds], the time Z1 [seconds] is 5.0 seconds or less.

[0014] (4) An adhesive tape according to any one of (1) to (3) above, in which when the adhesive tape is stretched by 250% in the TD direction, the adhesive tape is forcibly charged to 5,000 [V] in the TD direction, and the time taken for the charged voltage to decay to 5 [V] is defined as Z2 [seconds], the time Z2 [seconds] is 5.0 seconds or less.

[0015] (5) The permanently antistatic polymer is a polyolefin / polyether copolymer. An adhesive tape according to any one of (1) to (4) above.

[0017] (6) The base resin is an acrylic resin. (5) 2. The pressure-sensitive adhesive tape according to claim 1 .

[0018] (7) The content of the conductive material in the base material is 5.0% by weight or more and 45.0% by weight or less. (6) 2. The pressure-sensitive adhesive tape according to claim 1 .

[0019] (8) The adhesive tape according to any one of (1) to (7) above, wherein the adhesive layer further contains a curable resin that is cured by the application of energy, and the application of energy reduces the adhesive strength of the adhesive layer to at least one of the substrate and the component temporarily fixed on the adhesive layer.

[0020] (9) The substrate has a thickness of 30 μm or more and 200 μm or less. (8) 2. The pressure-sensitive adhesive tape according to claim 1 .

[0021] (10) The adhesive layer has a thickness of 5 μm or more and 100 μm or less. (9) 2. The pressure-sensitive adhesive tape according to claim 1 .

[0022] (11) The adhesive tape is used in a step of cutting the substrate, with the substrate fixed on the adhesive layer, from the substrate to a position halfway along the thickness direction of the base material to separate the substrate into individual pieces to form a plurality of components, and then, while stretching the adhesive tape in the planar direction, the components are pushed up from the base material side and pulled out from the opposite side of the base material to separate the components from the adhesive layer. (10) 2. The pressure-sensitive adhesive tape according to claim 1 . Effect of the Invention

[0023] According to the present invention, in an adhesive tape comprising a substrate and an adhesive layer laminated on one side of the substrate, the substrate of the adhesive tape contains a resin material and a conductive material, and satisfies the relationship YX < 1.0 seconds when, under conditions of 23°C and 50% RH, the adhesive tape is forcibly charged to 5000 [V] in the TD direction, the time it takes for the charged voltage to decay to 5 [V] is X [seconds], and further, when the adhesive tape is stretched 50% in the TD direction, the adhesive tape is forcibly charged to 5000 [V] in the TD direction, and the time it takes for the charged voltage to decay to 5 [V] is Y [seconds]. Therefore, when the adhesive tape to which a substrate or component is attached is stretched radially and then the substrate or component is picked up in a state where it is pushed up from the adhesive tape side, the pick-up can be performed by accurately preventing or suppressing the generation of static electricity in the substrate or component. Therefore, when picking up a semiconductor element as a component, it is possible to appropriately suppress or prevent damage to the semiconductor element caused by static electricity being discharged in the semiconductor element, which would result in a deterioration in the characteristics of the semiconductor element. [Brief description of the drawings]

[0024] [Figure 1] 1 is a vertical cross-sectional view showing an example of a semiconductor device manufactured using the pressure-sensitive adhesive tape of the present invention. [Diagram 2] FIG. 2 is a vertical cross-sectional view illustrating a method for producing the semiconductor device shown in FIG. 1 using the pressure-sensitive adhesive tape of the present invention. [Diagram 3] FIG. 2 is a vertical cross-sectional view illustrating a method for producing the semiconductor device shown in FIG. 1 using the pressure-sensitive adhesive tape of the present invention. [Figure 4] 3 is an enlarged cross-sectional view of the needle and its periphery located in the area [A] surrounded by a dotted line in FIG. 2. FIG. [Diagram 5] FIG. 1 is a longitudinal sectional view showing an embodiment of a pressure-sensitive adhesive tape. [Figure 6] 6 is a vertical cross-sectional view illustrating a method for producing the pressure-sensitive adhesive tape shown in FIG. 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The pressure-sensitive adhesive tape of the present invention will be described in detail below. First, prior to describing the pressure-sensitive adhesive tape of the present invention, a semiconductor device manufactured using the pressure-sensitive adhesive tape of the present invention will be described.

[0026] <Semiconductor device> Fig. 1 is a longitudinal sectional view showing an example of a semiconductor device manufactured using the pressure-sensitive 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". In addition, in each drawing referred to in this specification, the dimensions in the left-right direction and / or thickness direction are exaggerated and significantly different from the actual dimensions.

[0027] The semiconductor device 10 shown in FIG. 1 includes a semiconductor chip (semiconductor element) 20, an interposer (substrate) 30 that supports the semiconductor chip 20, a plurality of conductive bumps (terminals) 70, and a molded portion (sealing portion) 17 that seals the semiconductor chip 20.

[0028] The interposer 30 is an insulating substrate, and is made of various resin materials, such as polyimide, epoxy, cyanate, bismaleimide triazine (BT resin), etc. The shape of the interposer 30 in a plan view is usually a quadrangle such as a square or a rectangle.

[0029] On the upper surface (one surface) of the interposer 30, terminals 41 made of a conductive metal material such as copper are provided in a predetermined shape.

[0030] Furthermore, the interposer 30 has a plurality of vias (through holes) (not shown) formed therein, penetrating the interposer 30 in its thickness direction.

[0031] Each bump 70 has one end (upper end) electrically connected to a part of the terminal 41 through a respective via, and the other end (lower end) protrudes from the lower surface (the other surface) of the interposer 30.

[0032] The portion of the bump 70 protruding from the interposer 30 has a substantially spherical shape (ball shape).

[0033] The bumps 70 are mainly made of a brazing material such as solder, silver brazing, copper brazing, or phosphorus copper brazing.

[0034] Furthermore, terminals 41 are formed on the interposer 30. Terminals 21 of the semiconductor chip 20 are electrically connected to the terminals 41 via connecting portions 81.

[0035] In this embodiment, as shown in FIG. 1, the terminals 21 are configured to protrude from the surface side on which the semiconductor chip 20 is formed, and the terminals 41 are also configured to protrude from the interposer 30.

[0036] In addition, the gap between the semiconductor chip 20 and the interposer 30 is filled with an underfill material made of various resin materials, and the hardened underfill material forms a sealing layer 80. This sealing layer 80 has the function of improving the bonding strength between the semiconductor chip 20 and the interposer 30 and the function of preventing the intrusion of foreign matter, moisture, and the like into the gap.

[0037] Furthermore, on the upper side of the interposer 30, a molded portion 17 formed to cover the semiconductor chip 20 and the interposer 30 is made of a hardened semiconductor sealing material (sealant), thereby sealing the semiconductor chip 20 within the semiconductor device 10 and preventing the intrusion of foreign matter, moisture, etc. into the semiconductor chip 20.

[0038] 1, the semiconductor chip 20 (semiconductor element) has a semiconductor chip body 23 (semiconductor element body) and terminals 21 protruding from the lower surface side of the semiconductor chip body 23. The semiconductor chip body 23 has a circuit (not shown) built into its upper surface side, and is mainly made of a semiconductor material such as Si, SiC, GaN, or Ga2O3.

[0039] The semiconductor device 10 and the semiconductor chip 20 having such a configuration are manufactured as follows, for example, by a method for manufacturing a semiconductor device using an adhesive tape.

[0040] <Method of Manufacturing Semiconductor Device> 2 and 3 are longitudinal sectional views for explaining a method for manufacturing the semiconductor device shown in FIG. 1 using the adhesive tape of the present invention, and FIG. 4 is an enlarged sectional view of the periphery of a needle located in the area [A] surrounded by a dotted line in FIG. 2. In the following description, the upper side in FIG. 2 to FIG. 4 is referred to as "upper" and the lower side is referred to as "lower". In addition, in each drawing referred to in this specification, the dimensions in the left-right direction and / or thickness direction are exaggerated and greatly differ from the actual dimensions.

[0041] [1A] First, prepare an adhesive tape 100 composed of a laminate having a base material 4 and an adhesive layer 2 laminated on the upper surface of the base material 4. As shown in FIG. 2(a), place a semiconductor substrate 7 (semiconductor wafer) on the adhesive layer 2 in the center 122 of the tape, and lightly press the tape to laminate (temporarily fix) the semiconductor substrate 7 (attachment process).

[0042] A plurality of circuit groups are formed on the upper surface of the semiconductor substrate 7, and terminals 21 are formed on the lower surface. When the semiconductor substrate 7 is divided into individual pieces, the circuit groups and terminals 21 are also divided to obtain a plurality of semiconductor chips 20 (semiconductor chip main body portions 23). The semiconductor substrate 7 is placed on the adhesive layer 2 so that the upper surface on which the circuits are formed, i.e., the uneven surface on which the unevenness is formed, is in contact with the adhesive layer 2.

[0043] [2A] Next, as shown in FIG. 2(b), the adhesive tape 100 on which the semiconductor substrate 7 is laminated is placed on a dicer table 200.

[0044] [3A] Next, the outer periphery 121 of the adhesive layer 2 is fixed with a wafer ring 9, and then a dicing saw (blade) (not shown) is used to cut (diced) the semiconductor substrate 7 as a substrate into individual pieces. This results in semiconductor chips 20 as components on the adhesive tape 100 (singulating step; see FIG. 2(c)).

[0045] At this time, the adhesive tape 100 has a cushioning effect and prevents cracks, chips, etc., from occurring when the semiconductor substrate 7 is cut.

[0046] 2(c), the cutting of the semiconductor substrate 7 with the blade is performed so as to reach halfway in the thickness direction of the base material 4. This ensures that the semiconductor substrate 7 is divided into individual pieces, and the obtained semiconductor chips 20 (components) are temporarily fixed.

[0047] At this time, in order to prevent the scattering of dust generated when the semiconductor substrate 7 is cut and to suppress the semiconductor substrate 7 from being unnecessarily heated, cutting water is supplied to the semiconductor substrate 7 while the semiconductor substrate 7 is cut.

[0048] [4A] Next, the adhesive tape 100 with the semiconductor substrate 7 attached thereto is transferred from a dicing device (not shown) to a pick-up device (not shown). Then, with the outer periphery 121 of the adhesive layer 2 fixed to the wafer ring 9, the center portion 310 of the table 300 is pushed upward toward the outer periphery 320. This causes the adhesive tape 100 to be stretched radially, forming gaps between the semiconductor chips 20 (components) (expanding step; see FIG. 2(d)).

[0049] In the expanding step, an adhesive tape 100 is used. The adhesive tape 100 includes a base material 4 including a resin material and a conductive material, and an adhesive layer 2 including a base resin having adhesiveness as a main material. The adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction under conditions of 23°C and 50% RH, and the time required for the charged voltage to decay to 5 [V] is X [seconds]. Furthermore, the adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction under conditions of 23°C and 50% RH in a state where the adhesive tape 100 is stretched 50% in the TD direction, and the time required for the charged voltage to decay to 5 [V] is Y [seconds]. The base material 4 satisfies the relationship YX < 1.0 second.

[0050] By using such an adhesive tape 100, when the adhesive tape 100 to which the individual semiconductor chips 20 are attached is radially stretched in the expanding step, and then the individual semiconductor chips 20 are pushed up and picked up by the needles 430 in the picking up step, the generation of static electricity in the semiconductor chips 20 can be appropriately prevented or suppressed. This makes it possible to appropriately suppress or prevent the characteristics of the semiconductor chips 20 from deteriorating.

[0051] Thereafter, energy is applied to the adhesive layer 2 to reduce the adhesive strength to the semiconductor chip 20. The application of energy to the adhesive layer 2 may be performed before the expanding step. In addition, when individualization is not performed, energy may be applied before the dicing step to reduce the adhesive strength of the adhesive layer 2 to the semiconductor substrate 7.

[0052] [5A] Next, the semiconductor chip 20 is picked up on the stage 400 by a vacuum collet or air tweezers (pick-up step; see FIG. 2(e)).

[0053] In the pick-up process, for example, needle 430 (not shown in FIG. 2) is moved from a state in which it is stored in ejector head 410 as shown in FIG. 4(a) to a state in which it is protruded from ejector head 410 as shown in FIG. 4(b). That is, needle 430 is protruded in the thickness direction. As a result, semiconductor chip 20 attached to adhesive tape 100 is pushed up. This causes semiconductor chip 20 to be peeled off from adhesive tape 100. Thereafter, semiconductor chip 20 is picked up by suction using a vacuum collet or air tweezers, or the like, as shown in FIG. 4(c).

[0054] Through the above steps [1A] to [5A], the semiconductor chip 20 is obtained. That is, with the semiconductor substrate 7 fixed on the adhesive layer 2 of the adhesive tape 100, the adhesive tape 100 is cut so as to reach the middle of the thickness direction of the base material 4 from the semiconductor substrate 7, and the semiconductor substrate 7 is divided into individual pieces to form a plurality of semiconductor chips 20. Thereafter, after forming gaps between the semiconductor chips 20, the adhesive tape 100 is further stretched in the planar direction while pushing up the semiconductor chip 20 from the base material 4 side, and then pulled out from the opposite side of the base material 4, whereby the semiconductor chip 20 is separated from the adhesive layer 2.

[0055] [6A] Next, the picked-up semiconductor chip 20 is transferred from the vacuum collet or air tweezers to a mounting probe or the like and turned upside down. After that, as shown in Fig. 3(a), the semiconductor chip 20 is placed on the interposer 30. At this time, the terminals 21 of the semiconductor chip 20 and the terminals 41 of the interposer 30 are opposed to each other via the solder bumps 85.

[0056] [7A] Next, heating is performed as shown in FIG. 3(b). This melts the solder bumps 85. As a result, connection parts 81 that connect the terminals 21 and 41 are obtained. Then, the terminals 21 and 41 are electrically connected via the connection parts 81 (mounting process; see FIG. 3(c)).

[0057] [8A] Next, an underfill material (sealing material) made of various resin materials is filled into the gap formed between the semiconductor chip 20 and the interposer 30. Thereafter, the underfill material is cured to form a sealing layer 80 made of the cured underfill material (sealing layer forming process; see FIG. 3(d)).

[0058] [9A] Next, a molded portion 17 (sealing portion) that covers the semiconductor chip 20 is formed on the upper side of the interposer 30. In addition, bumps 70 that are electrically connected to the terminals 41 through vias (not shown) that penetrate the interposer 30 are disposed on the lower side of the interposer 30 (see FIG. 3(e)).

[0059] For sealing with the molded part 17, for example, a mold having an internal space corresponding to the shape of the molded part 17 to be formed is prepared, and a powdered semiconductor sealing material is filled into the internal space. In this state, the semiconductor sealing material is heated to harden, thereby obtaining the molded part 17. The semiconductor device 10 is obtained by the method for manufacturing a semiconductor device having the steps described above.

[0060] An adhesive tape 100 used in the method for manufacturing such a semiconductor device 10 will be described below.

[0061] <Adhesive tape> Fig. 5 is a longitudinal sectional view showing an embodiment of a pressure-sensitive adhesive tape of the present invention. In the following description, the upper side in Fig. 5 will be referred to as "upper" and the lower side as "lower".

[0062] The adhesive tape 100 is constituted by a laminate including a base material 4 containing a resin material and a conductive material, and an adhesive layer 2 laminated on one surface of the base material 4. The adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction under conditions of 23°C and 50% RH, and the time taken for the charged voltage to decay to 5 [V] is defined as X [seconds]. Furthermore, the adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction under conditions of 23°C and 50% RH in a state where the adhesive tape 100 is stretched 50% in the TD direction, and the time taken for the charged voltage to decay to 5 [V] is defined as Y [seconds]. The adhesive tape 100 satisfies the relationship YX < 1.0 second.

[0063] Here, in the pick-up process, when the individual semiconductor chips 20 are pushed up and picked up by the needles 430, it is required to accurately prevent or suppress the generation of static electricity in the semiconductor chips 20.

[0064] With respect to the required characteristics of the adhesive tape 100, the inventors have studied the above and determined that the base material 4 of the adhesive tape 100 contains a resin material and a conductive material, as described above. The adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction under conditions of 23°C and 50% RH, and the time it takes for the charged voltage to decay to 5 [V] is X [seconds]. Furthermore, the adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction under conditions of 23°C and 50% RH in a state where the adhesive tape 100 is stretched 50% in the TD direction under conditions of 23°C and 50% RH, and the time it takes for the charged voltage to decay to 5 [V] is Y [seconds]. The adhesive tape 100 satisfies the relationship YX < 1.0 second.

[0065] The forced charging of the adhesive tape 100 in the TD direction and the subsequent charging voltage are measured using a charge decay data analyzer ("STATIC DECAY METER MODEL 406C" manufactured by electro-tech systems, inc.) under conditions of 23°C and 50% RH. More specifically, the charge decay data analyzer is set so that a voltage is applied in the TD direction to the surface of the substrate 4 of the adhesive tape 100 opposite the adhesive layer 2, and then the adhesive tape 100 is forcedly charged to 5000 [V], and the time it takes for the charging voltage to decay to 5 [V] is measured.

[0066] After such forced electrification in the TD direction, the decay time for the charged voltage to decay to 5 [V] is compared between the adhesive tape 100 in an unstretched state (stretch rate 0%) and the adhesive tape 100 in a state stretched 50% in the TD direction (stretch rate 50%). When the decay time measured for the former is X [seconds] and the decay time measured for the latter is Y [seconds], the adhesive tape 100 satisfies the relational expression (YX) of the difference between them being less than 1.0 second.

[0067] What this relational expression means is that even if the adhesive tape 100 to which the individual semiconductor chips 20 are attached is stretched radially in the expanding process, the amount of change in the susceptibility of the adhesive tape 100 to charging is small.

[0068] Therefore, even if static electricity is unintentionally generated in the semiconductor chip 20 when the individual semiconductor chip 20 is picked up by pushing up the needle 430 in the pick-up process, the static electricity can be quickly dissipated. This makes it possible to suppress damage to the semiconductor chip 20 caused by the discharge of static electricity, and to appropriately suppress or prevent the characteristics of the semiconductor chip 20 from deteriorating.

[0069] By repeating the steps [5A] to [9A], a plurality of semiconductor devices 10 can be obtained from one semiconductor substrate 7. At this time, the repetition of the steps [5A] to [9A] may be stopped once while several semiconductor chips 20 remain on the adhesive tape 100, and then the steps [5A] to [9A] may be started again. At this time, if the stop time is long, the adhesive tape 100 to which the semiconductor chips 20 are attached may be removed (peeled off) from the dicer table. Even in such a case, the generation of static electricity on the semiconductor chips 20 can be appropriately suppressed or prevented.

[0070] A stretch rate of 50% refers to a state in which the pressure-sensitive adhesive tape 100 is stretched to 1.5 times its initial length, and a stretch rate of 100%, which will be described later, refers to a state in which the pressure-sensitive adhesive tape 100 is stretched to twice its initial length.

[0071] The stretch ratios of 50% and 100% are set as values ​​that can sufficiently cover the range in which the stretch ratio is increased from the perspective of pick-up efficiency or other points of view when the adhesive tape 100 is stretched in the expanding process. Specifically, when the semiconductor chips 20 are miniaturized, the number of cut lines increases, so that a larger stretch ratio is required to maintain the chip spacing. In light of this background, the adhesive tape 100 is likely to maintain its antistatic performance even when subjected to an expanding process with a large stretch ratio, and can suppress the occurrence of problems caused by static electricity.

[0072] The substrate 4 and adhesive layer 2 of this adhesive tape 100 (dicing tape) will be described in detail below.

[0073] <Base material 4> The base material 4 contains a resin material and a conductive material as main materials, and has a function of supporting the adhesive layer 2 provided on the base material 4. Moreover, in the adhesive tape 100 including the base material 4, the types of the resin material and the conductive material are selected and their contents, etc. are set so as to satisfy the relationship YX < 1.0 second, as described above.

[0074] The resin material is not particularly limited, but examples thereof include polyethylenes such as low-density polyethylene, linear polyethylene, medium-density polyethylene, high-density polyethylene, and very low-density polyethylene; polypropylenes such as random copolymer polypropylene, block copolymer polypropylene, and homopolypropylene; polyolefin resins (olefin polymers) such as polyvinyl chloride, polybutene, polybutadiene, and polymethylpentene; ionomers such as ethylene-vinyl acetate copolymers, zinc ion crosslinkers, and sodium ion crosslinkers; olefins such as ethylene-(meth)acrylic acid copolymers, ethylene-(meth)acrylic acid ester (random, alternating) copolymers, ethylene-propylene copolymers, ethylene-butene copolymers, and ethylene-hexene copolymers. Thermoplastic resins such as olefin copolymers, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, and polyester resins (ester polymers) such as polybutylene naphthalate, polyurethane, polyimide, polyamide, polyether ketone such as polyether ether ketone, polyether sulfone, polystyrene, fluororesin, silicone resin, cellulose resin, styrene thermoplastic elastomer (styrene polymer), olefin thermoplastic elastomer (olefin polymer) such as polypropylene thermoplastic elastomer, acrylic resin, polyester thermoplastic elastomer, polyvinyl isoprene, and polycarbonate (carbonate polymer), or mixtures of these thermoplastic resins are used. Among these, ester polymers, styrene polymers, olefin polymers, carbonate polymers, or copolymers containing at least one of these polymers are preferred.

[0075] These resin materials can transmit energy rays such as light (visible light, near infrared light, ultraviolet light), X-rays, and electron beams, and therefore can be preferably used in the expanding process when energy rays are irradiated onto the adhesive layer 2 from the substrate 4 side by passing through the substrate 4.

[0076] In particular, it is preferable to use, as the resin material, an elastomer alone, a mixture of polypropylene and an elastomer, or a mixture of polyethylene and an elastomer, which can relatively easily satisfy the relationship YX < 1.0 second.

[0077] Among the above-mentioned styrene-based thermoplastic elastomers, olefin-based thermoplastic elastomers, and polyester-based thermoplastic elastomers, the styrene-based thermoplastic elastomers, which are block copolymers consisting of polystyrene segments and vinyl polyisoprene segments, are particularly preferred as the elastomer, as this makes it easier to satisfy the relationship YX < 1.0 seconds.

[0078] The base material 4 also contains a conductive material dispersed in the resin material contained as the main material. This allows the conductive material to function as an antistatic agent. As a result, an adhesive tape 100 that satisfies the relationship YX < 1.0 sec is obtained.

[0079] The conductive material is not particularly limited, but examples thereof include conductive polymers, surfactants, permanently antistatic polymers (IDPs), metal materials, metal oxide materials, and carbon-based materials (carbon materials), and one or a combination of two or more of these may be used.

[0080] Examples of conductive polymers include polythiophene, polyaniline, polypyrrole, polyacetylene, PEDOT (poly-ethylenedioxythiophene), PEDOT / PSS, poly(p-phenylene), polyfluorene, polycarbazole, polysilane, or derivatives thereof, and one or more of these can be used in combination.

[0081] Examples of polythiophenes or derivatives thereof include polythiophene, poly(3,4)-ethylenedioxythiophene, and poly(3-thiophene-β-ethanesulfonic acid).

[0082] Examples of polyaniline or its derivatives include polyaniline, polymethylaniline, and polymethoxyaniline.

[0083] Examples of polypyrrole or its derivatives include polypyrrole, poly 3-methylpyrrole, poly 3-octylpyrrole, and the like.

[0084] Examples of the surfactant include anionic surfactants, cationic surfactants, nonionic surfactants, and amphoteric surfactants.

[0085] Examples of the permanently antistatic polymer (IDP) include various IDPs such as polyesteramide-based, polyetherester polyolefin-based, polyetherester amide-based, and polyurethane-based IDPs.

[0086] Examples of the metal material include gold, silver, copper or silver-coated copper, nickel, etc. Powders of these metal materials (metal powders) are preferably used.

[0087] Examples of metal oxide materials include indium tin oxide (ITO), indium oxide (IO), antimony tin oxide (ATO), indium zinc oxide (IZO), tin oxide (SnO2), etc. Powders of these metal oxide materials (metal oxide powders) are preferably used.

[0088] Examples of carbon-based materials (carbon materials) include carbon black, carbon nanotubes such as single-walled carbon nanotubes and multi-walled carbon nanotubes, carbon nanofibers, CN nanotubes, CN nanofibers, BCN nanotubes, BCN nanofibers, graphene, and the like.

[0089] Among these, the conductive material is preferably at least one of conductive polymers, permanently antistatic polymers (IDPs), metal oxide materials, and carbon-based materials. These materials have small temperature dependency of resistivity, so that even if the substrate 4 is heated, for example, the amount of change in resistance value can be small.

[0090] The content of the conductive material in the substrate 4 varies slightly depending on the type of conductive material, but is preferably 5.0% by weight to 45.0% by weight, more preferably 5.0% by weight to 30% by weight, and even more preferably 10% by weight to 20% by weight. This makes it easy to realize an adhesive tape 100 that satisfies the relationship YX<1.0 second.

[0091] The substrate 4 may contain softeners such as mineral oil, fillers such as calcium carbonate, silica, talc, mica, and clay, antioxidants, light stabilizers, lubricants, dispersants, neutralizing agents, colorants, and the like.

[0092] The content of the resin material in the substrate 4 is preferably 50% by weight or more and 95% by weight or less, and more preferably 65% ​​by weight or more and 90% by weight or less, which makes it easy to realize an adhesive tape 100 that satisfies the relationship YX<1.0 second.

[0093] The thickness of the base material 4 is not particularly limited, but is preferably 30 μm or more and 200 μm or less, and more preferably 40 μm or more and 150 μm or less. When the thickness of the base material 4 is within this range, the workability of dicing the semiconductor substrate 7 in the dicing process can be improved. In addition, the adhesive tape 100 that satisfies the relationship YX < 1.0 second can be easily realized. Furthermore, the occurrence of breakage in the base material 4 can be more reliably prevented when the semiconductor chip 20 is expanded and picked up.

[0094] The surface roughness Ra of the substrate 4 is, for example, preferably 0.2 μm or more and 2.0 μm or less, more preferably 0.5 μm or more and 1.5 μm or less. When the surface roughness Ra of the substrate 4 is within this range, the adhesion between the substrate 4 and the adhesive layer 2 is improved. When the adhesive tape 100 to which the individualized semiconductor chips 20 are attached is radially stretched in the expanding step, and when the semiconductor chips 20 are picked up in a state in which they are pushed up by the needles 430 in the picking up step, peeling between the substrate 4 and the adhesive layer 2 can be appropriately suppressed or prevented. The surface roughness Ra is the arithmetic mean roughness Ra specified in JIS B 0601:2013. For the arithmetic mean roughness Ra, a stylus-type surface roughness measuring instrument specified in JIS B 0633:2001 is used.

[0095] In addition, it is preferable that the substrate 4 has exposed on its surface a functional group, such as a hydroxyl group or an amino group, that is reactive with the constituent material contained in the adhesive layer 2. This makes it possible to more appropriately suppress or prevent the peeling between the substrate 4 and the adhesive layer 2.

[0096] Furthermore, the base material 4 is preferably one in which the conductive material is uniformly dispersed, but the conductive material may be unevenly distributed on the adhesive layer 2 side or the opposite side of the base material 4. When the conductive material is unevenly distributed in the base material 4, the base material 4 may be a single layer body in which the content of the conductive material varies in the thickness direction, or a laminate body formed by laminating a plurality of layers with different contents of the conductive material. Furthermore, when the base material 4 is constituted by a laminate body (multilayer body), at least one of the type of resin material and the type of conductive material may be different for each layer.

[0097] <Adhesive layer 2> The adhesive layer 2 adheres to and supports the semiconductor substrate 7 in the dicing step, and when energy is applied and hardened, has enough adhesion to pick up the semiconductor chip 20 in the pick-up step.

[0098] The adhesive layer 2 is made of a resin composition containing, as main materials, (1) a base resin having adhesive properties and (2) a curable resin that cures the adhesive layer 2.

[0099] Each component contained in this resin composition will be described in detail below. (1) Base resin The base resin has adhesiveness, and provides the adhesive layer 2 with adhesiveness to the semiconductor substrate 7 .

[0100] Examples of the base resin include known resins used as adhesive layer components, such as acrylic resins (adhesives), silicone resins (adhesives), polyester resins (adhesives), polyvinyl acetate resins (adhesives), polyvinyl ether resins (adhesives), styrene elastomer resins (adhesives), polyisoprene resins (adhesives), polyisobutylene resins (adhesives), and urethane resins (adhesives). Of these, it is preferable to use acrylic resins. Acrylic resins are preferably used as base resins because they have excellent heat resistance and are relatively easy and inexpensive to obtain.

[0101] The acrylic resin refers to a resin having a polymer (homopolymer or copolymer) whose main monomer component is a (meth)acrylic acid ester as a base polymer.

[0102] The (meth)acrylic acid ester is not particularly limited, but examples thereof include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, and decyl (meth)acrylate. Examples of the acrylate include (meth)acrylic acid alkyl esters such as (meth)acrylic acid isodecyl, (meth)acrylic acid undecyl, (meth)acrylic acid dodecyl, (meth)acrylic acid tridecyl, (meth)acrylic acid tetradecyl, (meth)acrylic acid pentadecyl, (meth)acrylic acid hexadecyl, (meth)acrylic acid heptadecyl, and (meth)acrylic acid octadecyl, (meth)acrylic acid cycloalkyl esters such as (meth)acrylic acid cyclohexyl, and (meth)acrylic acid aryl esters such as (meth)acrylic acid phenyl, and one or more of these can be used in combination. Among these, (meth)acrylic acid alkyl esters such as (meth)acrylic acid methyl, (meth)acrylic acid ethyl, (meth)acrylic acid butyl, (meth)acrylic acid 2-ethylhexyl, and (meth)acrylic acid octyl are preferred. (Meth)acrylic acid alkyl esters are particularly excellent in heat resistance and can be obtained relatively easily and inexpensively.

[0103] In this specification, the term "(meth)acrylic acid ester" is used to include both acrylic acid ester and methacrylic acid ester.

[0104] The acrylic resin may contain a copolymerizable monomer as a monomer component constituting the polymer, if necessary, for the purpose of modifying the cohesive strength, heat resistance, and the like.

[0105] The copolymerizable monomer is not particularly limited, and examples thereof include hydroxyl group-containing monomers such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate; epoxy group-containing monomers such as glycidyl (meth)acrylate; carboxyl group-containing monomers such as (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, and isocrotonic acid; acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; amide monomers such as (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-butyl(meth)acrylamide, N-methylol(meth)acrylamide, N-methylolpropane(meth)acrylamide, N-methoxymethyl(meth)acrylamide, and N-butoxymethyl(meth)acrylamide; amino group-containing monomers such as aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, and t-butylaminoethyl (meth)acrylate; p) Cyano group-containing monomers such as acrylonitrile; olefin monomers such as ethylene, propylene, isoprene, butadiene, and isobutylene; styrene monomers such as styrene, α-methylstyrene, and vinyl toluene; vinyl ester monomers such as vinyl acetate and vinyl propionate; vinyl ether monomers such as methyl vinyl ether and ethyl vinyl ether; halogen atom-containing monomers such as vinyl chloride and vinylidene chloride; alkoxy group-containing monomers such as methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate; and monomers having a nitrogen atom-containing ring such as N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N-vinylmorpholine, N-vinylcaprolactam, and N-(meth)acryloylmorpholine. These may be used alone or in combination of two or more.

[0106] The content of the copolymerizable monomer is preferably 40% by weight or less, and more preferably 10% by weight or less, of all monomer components constituting the acrylic resin.

[0107] The structure derived from the copolymerizable monomer may be contained at a terminal of the main chain of the polymer constituting the acrylic resin, may be contained in the main chain, or may be contained both at a terminal of the main chain and in the main chain.

[0108] The copolymerizable monomer may be a polyfunctional monomer for the purpose of crosslinking between polymers.

[0109] Examples of polyfunctional monomers include 1,6-hexanediol (meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, glycerin di(meth)acrylate, epoxy (meth)acrylate, polyester (meth)acrylate, urethane (meth)acrylate, divinylbenzene, butyl di(meth)acrylate, hexyl di(meth)acrylate, and the like. One or a combination of two or more of these can be used.

[0110] Also usable as the copolymerizable monomer are ethylene-vinyl acetate copolymers and vinyl acetate polymers.

[0111] Such acrylic resins (polymers) are produced by polymerizing a single monomer component or a mixture of two or more monomer components. For the polymerization of these monomer components, a polymerization method such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization, etc. is used.

[0112] From the viewpoint of preventing contamination of the semiconductor substrate 7 and the like in the dicing process, it is preferable that the acrylic resin contains a small amount of low molecular weight substances. Specifically, the weight average molecular weight of the acrylic resin is preferably set to 300,000 to 5,000,000, more preferably 400,000 to 4,000,000, and even more preferably 500,000 to 1,500,000. If the weight average molecular weight of the acrylic resin is less than the lower limit, depending on the type of monomer component, the contamination prevention property for the semiconductor substrate 7 may decrease, and adhesive residue may be generated when the semiconductor chip 20 is peeled off. The weight average molecular weight is calculated as standard polystyrene by gel permeation chromatography (GPC).

[0113] The acrylic resin preferably has a functional group (reactive functional group) that is reactive to a crosslinking agent or a photopolymerization initiator, such as a hydroxyl group or a carboxyl group (particularly a hydroxyl group). This allows the crosslinking agent or the photopolymerization initiator to be linked to the acrylic resin, which is a polymer component. This makes it possible to appropriately suppress or prevent the crosslinking agent or the photopolymerization initiator from leaking out of the adhesive layer 2. As a result, the adhesive strength of the adhesive layer 2 can be reliably reduced by applying energy to the adhesive layer 2.

[0114] (2) Curing resin The curable resin has a curing property such that it is cured by, for example, irradiation with energy rays. When the base resin is incorporated into the crosslinked structure of the curable resin by this curing, the adhesive strength of the adhesive layer 2 decreases.

[0115] As the curable resin, for example, a low molecular weight compound having at least two or more polymerizable carbon-carbon double bonds as functional groups in the molecule, which are capable of three-dimensional crosslinking by irradiation with energy rays such as ultraviolet rays and electron beams, is used. Specific examples of the curable resin include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, tetraethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, and the like. acrylate, 1,4-butylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, esterification products of (meth)acrylic acid and polyhydric alcohol such as glycerin di(meth)acrylate, ester acrylate oligomers, cyanurate compounds having a carbon-carbon double bond-containing group such as 2-propenyl-di-3-butenyl cyanurate, tris(2-acryloxyethyl)isocyanurate, tris(2-methacryloxyethyl)isocyanurate, 2-hydroxyethyl Examples of the isocyanurate-based compound having a carbon-carbon double bond-containing group such as bis(2-acryloxyethyl)isocyanurate, bis(2-acryloxyethyl)2-[(5-acryloxyhexyl)-oxy]ethyl isocyanurate, tris(1,3-diacryloxy-2-propyl-oxycarbonylamino-n-hexyl)isocyanurate, tris(1-acryloxyethyl-3-methacryloxy-2-propyl-oxycarbonylamino-n-hexyl)isocyanurate, tris(4-acryloxy-n-butyl)isocyanurate, commercially available oligoester acrylates, aromatic and aliphatic urethane acrylates, bisphenol A epoxy acrylates, etc., can be used alone or in combination of two or more of these. Among these, it is preferable to include at least one of the esters of (meth)acrylic acid and polyhydric alcohol, urethane acrylates, and bisphenol A epoxy acrylates.This makes it possible to more reliably cure the curable resin by application of energy, i.e., by irradiation with energy rays.

[0116] The resin composition may contain two or more types of curable resins having different weight average molecular weights. By using two or more types of curable resins in combination, the degree of crosslinking of the resin by energy ray irradiation can be easily controlled.

[0117] When the resin composition contains a first curable resin and a second curable resin having a higher weight-average molecular weight, the weight-average molecular weight of the first curable resin is preferably about 100 to 1000, more preferably about 200 to 500. The weight-average molecular weight of the second curable resin is preferably about 1000 to 30000, more preferably about 1000 to 10000, and even more preferably about 2000 to 5000. Furthermore, the number of functional groups of the first curable resin is preferably 1 to 5, and the number of functional groups of the second curable resin is preferably 6 or more. By satisfying such a relationship, the above-mentioned effect can be more significantly exhibited.

[0118] The curable resin is preferably mixed in an amount of 30 parts by weight to 200 parts by weight, more preferably 50 parts by weight to 140 parts by weight, per 100 parts by weight of the base resin, to obtain an adhesive layer 2 that can reliably exhibit the functions of the curable resin and the base resin.

[0119] In addition, when a double bond-introduced acrylic resin, i.e., an acrylic resin having a carbon-carbon double bond in a side chain, in a main chain, or at an end of the main chain, is used as the acrylic resin described above, the addition of a curable resin to the resin composition may be omitted. The double bond-introduced acrylic resin can impart curability to the adhesive layer 2 without a curable resin due to the function of the carbon-carbon double bond.

[0120] (3) Photopolymerization initiator The resin composition may contain a photoinitiator to facilitate initiation of polymerization of the curable resin.

[0121] Examples of photopolymerization initiators include 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, benzyl diphenyl sulfide, tetramethylthiuram monosulfide, 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'- Dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, 1-hydroxycyclohexyl phenyl ketone, Michler's ketone, acetophenone, methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinopropane-1, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl, benzoin, Dibenzyl, α-hydroxycyclohexyl phenyl ketone, benzil dimethyl ketal, 2-hydroxymethylphenylpropane, 2-naphthalenesulfonyl chloride, 1-phenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime, benzophenone, benzoylbenzoic acid, 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-4-methoxybenzophenone, o-acryloxybenzophenone, p-acryloxybenzophenone Benzophenone-4-carboxylate esters of acrylates such as benzophenone, o-methacryloxybenzophenone, p-methacryloxybenzophenone, p-(meth)acryloxyethoxybenzophenone, 1,4-butanediol mono(meth)acrylate, 1,2-ethanediol mono(meth)acrylate, 1,8-octanediol mono(meth)acrylate, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,Examples of the thiol-substituted thiol include 4-diethylthioxanthone, 2,4-diisopropylthioxanthone, azobisisobutyronitrile, β-chloroanthraquinone, camphorquinone, halogenated ketones, acylphosphinoxides, acylphosphonates, polyvinylbenzophenone, chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, 2-ethylanthraquinone, t-butylanthraquinone, and 2,4,5-triarylimidazole dimers. These can be used alone or in combination of two or more.

[0122] The photopolymerization initiator is preferably mixed in a ratio of 0.1 to 50 parts by weight, more preferably 0.5 to 10 parts by weight, relative to 100 parts by weight of the base resin, to obtain an adhesive layer 2 that can reliably exhibit the functions of the photopolymerization initiator.

[0123] (4) Crosslinking agent The resin composition may contain a crosslinking agent. By including a crosslinking agent, the adhesive layer 2 can be imparted with an appropriate hardness.

[0124] The crosslinking agent is not particularly limited, but examples thereof include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, urea resin-based crosslinking agents, methylol-based crosslinking agents, chelate-based crosslinking agents, aziridine-based crosslinking agents, melamine-based crosslinking agents, polyvalent metal chelate-based crosslinking agents, acid anhydride-based crosslinking agents, polyamine-based crosslinking agents, carboxyl group-containing polymer-based crosslinking agents, etc. Among these, isocyanate-based crosslinking agents are preferred.

[0125] The isocyanate-based crosslinking agent is not particularly limited, but examples thereof include polyisocyanate compounds of polyisocyanates and trimers of polyisocyanate compounds, trimers of terminal isocyanate compounds obtained by reacting a polyisocyanate compound with a polyol compound, and blocked polyisocyanate compounds in which a terminal isocyanate urethane prepolymer is blocked with phenol, oximes, or the like.

[0126] Examples of polyisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, 4,4'-diphenylether diisocyanate, 4,4'-[2,2-bis(4-phenoxyphenyl)propane]diisocyanate, and 2,2,4-trimethyl-hexamethylene diisocyanate. These can be used alone or in combination of two or more. Among these, at least one polyisocyanate selected from the group consisting of 2,4-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, and hexamethylene diisocyanate is preferred.

[0127] The crosslinking agent is preferably mixed in a ratio of 0.01 to 30 parts by weight, more preferably 0.1 to 20 parts by weight, relative to 100 parts by weight of the base resin, to obtain an adhesive layer 2 that can reliably exert the function of the crosslinking agent.

[0128] (5) Plasticizers The resin composition may contain a plasticizer, which can improve the flexibility of the adhesive layer 2 when the adhesive strength of the adhesive layer 2 is reduced by the application of energy.

[0129] The plasticizer is not particularly limited, but examples thereof include phthalate ester plasticizers such as DOP (dioctyl phthalate), DBP (dibutyl phthalate), DIBP (diisobutyl phthalate), and DHP (diheptyl phthalate); aliphatic dibasic acid ester plasticizers such as DOA (di-2-ethylhexyl adipate), DIDA (diisodecyl adipate), and DOS (di-2-ethylhexyl sebacate); aromatic carboxylate ester plasticizers such as ethylene glycol benzoates; trimellitate ester plasticizers such as TOTM (trioctyl trimellitate); and adipate ester plasticizers. These may be used alone or in combination of two or more.

[0130] The plasticizer is preferably mixed in a ratio of 0.1 to 5.0 parts by weight, more preferably 0.5 to 3.0 parts by weight, relative to 100 parts by weight of the base resin, which can reliably improve the flexibility of the adhesive layer 2.

[0131] (6) Other ingredients The resin composition constituting the adhesive layer 2 may contain at least one of the following other components: conductive materials, tackifiers, antioxidants, adhesion adjusters, fillers, colorants, flame retardants, softeners, antioxidants, surfactants, etc.

[0132] The conductive material is not particularly limited as long as it has conductivity, but the same conductive materials as those described above as the conductive material contained in the base material 4 can be used.

[0133] By adding a conductive material to the adhesive layer 2, an antistatic function can be imparted to the adhesive layer 2. This appropriately suppresses or prevents the generation of static electricity in the semiconductor chip 20 during the dicing process and the pick-up process.

[0134] The tackifier is not particularly limited, but examples thereof include rosin resins, terpene resins, coumarone resins, phenolic resins, aliphatic petroleum resins, aromatic petroleum resins, and aliphatic-aromatic copolymer petroleum resins. One or a combination of two or more of these may be used.

[0135] By appropriately selecting the type and content of each of the above components, an adhesive layer 2 is obtained that adheres to and supports the semiconductor substrate 7 during the dicing process, and when energy is applied and hardens, has enough adhesion to pick up the semiconductor chip 20 during the pick-up process.

[0136] The thickness of the adhesive layer 2 is not particularly limited, but is preferably 5 μm to 100 μm, more preferably 5 μm to 50 μm. By setting the thickness of the adhesive layer 2 within this range, an adhesive layer 2 having a degree of adhesion that exhibits good adhesive strength to the semiconductor substrate 7 in the dicing process and good peelability in the pick-up process can be obtained.

[0137] The adhesive layer 2 may be a laminate (multilayer body) formed by laminating a plurality of layers made of different resin compositions.

[0138] The resin composition may be one in which the addition of a curable resin is omitted. That is, the adhesive layer 2 may be one whose adhesive strength does not decrease even when energy is applied thereto.

[0139] As described above, the adhesive tape 100 (dicing tape) having the above-mentioned substrate 4 and adhesive layer 2 is forcibly charged to 5000 [V] in the TD direction under conditions of 23°C and 50% RH, and the time required for the charged voltage to decay to 5 [V] is defined as X [seconds]. Furthermore, when the adhesive tape 100 is stretched 50% in the TD direction under conditions of 23°C and 50% RH, the adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction, and the time required for the charged voltage to decay to 5 [V] is defined as Y [seconds]. It is sufficient for the adhesive tape 100 to satisfy the relationship YX < 1.0 second, but it is preferable for it to satisfy the relationship YX < 0.5 second, and it is more preferable for it to satisfy the relationship 0.05 second < YX < 0.3 second. It can be said that this makes it possible to set a smaller amount of change in the tendency of the adhesive tape 100 to become charged when the adhesive tape 100 to which the individual semiconductor chips 20 are attached is radially stretched in the expanding step. Therefore, after the expanding step, when the individual semiconductor chips 20 are picked up in a state where they are pushed up by the needles 430 in the pick-up step, the generation of static electricity in the semiconductor chips 20 can be more accurately prevented or suppressed, and the semiconductor chips 20 can be picked up.

[0140] In addition, the time X is preferably 1.0 second or less, and more preferably 0.1 second or more and 0.5 second or less. This means that the adhesive tape 100 is set to be small in its tendency to become charged before the adhesive tape 100 to which the individual semiconductor chips 20 are attached is radially stretched in the expanding step. This makes it possible to appropriately suppress or prevent static electricity from being generated in the semiconductor chips 20 when the semiconductor substrate 7 is cut in the dicing step.

[0141] Furthermore, the time Y is preferably 2.0 seconds or less, and more preferably 0.1 seconds or more and 0.8 seconds or less. This means that the adhesive tape 100 is set to be small in its tendency to become charged after the adhesive tape 100 to which the individual semiconductor chips 20 are attached is radially stretched in the expanding step. This makes it possible to appropriately suppress or prevent static electricity from being generated in the semiconductor chips 20 when the semiconductor chips 20 are picked up in the pick-up step.

[0142] In addition, under conditions of 23°C and 50% RH, when the adhesive tape 100 is stretched 100% in the TD direction, the adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction, and the time for the charged voltage to decay to 5 [V] is defined as Z1 [seconds]. This time Z1 [seconds] is preferably 5.0 seconds or less, and more preferably 3.0 seconds or less. Furthermore, under conditions of 23°C and 50% RH, when the adhesive tape 100 is stretched 250% in the TD direction, the adhesive tape 100 is forcibly charged to 5000 [V] in the TD direction, and the time for the charged voltage to decay to 5 [V] is defined as Z2 [seconds]. This time Z2 [seconds] is preferably 5.0 seconds or less, and more preferably 4.0 seconds or less. As a result, when the adhesive tape 100 to which the individual semiconductor chips 20 are attached is radially stretched in the expanding step, it can be said that the degree of the tendency of the adhesive tape 100 to become charged due to the stretching of the adhesive tape 100 is reliably set small without changing with the degree of stretching. Therefore, after the expanding step, when the individual semiconductor chips 20 are picked up in a state where they are pushed up by the needles 430 in the pick-up step, the generation of static electricity in the semiconductor chips 20 can be more reliably prevented or suppressed, and the semiconductor chips 20 can be picked up.

[0143] Such an adhesive tape 100 satisfies the requirement that the relational expression (YX) is less than 0.5 seconds, and thus, in a state where a slice of a silicon wafer having a thickness of 0.2 mm and a length of 4 to 6 inches is fixed on the adhesive layer 2 of the adhesive tape 100, the slice is cut so as to reach the middle of the thickness direction of the base material 4, and the slice is divided into individual pieces to form a plurality of individual pieces having a length and width of 6 mm, and then, the adhesive layer 2 is subjected to ultraviolet irradiance of 55 W / cm 2 , UV irradiation amount: 200mj / cm 2 After irradiating ultraviolet light under the above conditions, the adhesive tape 100 is stretched 8 mm in the surface direction, and the individualized objects are pushed up 0.4 mm from the substrate 4 side by four pins arranged with a tip curvature radius of 100 μm and an interval of 4 mm, and then pulled out from the opposite side of the substrate 4. Of the 50 individualized objects, the number of those with discharge marks is preferably 3 or less, more preferably 1 or less. In addition, these series of evaluations are performed without using an ionizer in order to perform them under harsher conditions. As a result, it can be said that the individualized objects can be picked up in a state in which the generation of static electricity in the individualized objects, i.e., the semiconductor chips 20, is more accurately prevented or suppressed.

[0144] Next, the adhesive tape 100 having the above-mentioned configuration can be manufactured, for example, as follows.

[0145] <Method of manufacturing adhesive tape> Fig. 6 is a vertical cross-sectional view for explaining a method for producing the adhesive tape shown in Fig. 5. In the following explanation, the upper side in Fig. 6 is referred to as "upper" and the lower side is referred to as "lower".

[0146] [1B] First, a substrate 4 is prepared (see FIG. 6(a)). The method for producing the substrate 4 is not particularly limited, and examples of the method include general molding methods such as extrusion molding methods such as a calendar method, an inflation extrusion method, and a T-die extrusion method, and a wet casting method. When the substrate 4 is formed of a laminate, examples of the method for producing the substrate 4 having such a configuration include molding methods such as a co-extrusion method and a dry lamination method.

[0147] The base material 4 may be used without stretching, or may be subjected to uniaxial or biaxial stretching treatment as necessary.

[0148] Before forming the base material 4 into a sheet, the raw materials are kneaded with various kneading machines or the like. In this case, the kneading temperature is preferably higher than 200°C, more preferably 210°C or higher, and even more preferably 220°C or higher. This allows the raw materials to be kneaded more uniformly, and the uniform dispersion of the antistatic agent in the base material 4 can be further improved. As a result, the pressure-sensitive adhesive tape 100 that satisfies the above-mentioned relational expression can be easily manufactured.

[0149] The upper limit of the kneading temperature is appropriately set depending on the raw materials, but is preferably 350° C. or less, and more preferably 300° C. or less, which can suppress denaturation of the raw materials due to heat.

[0150] Furthermore, the kneading time at the above kneading temperature is preferably 3 minutes or more, and more preferably 4 minutes or more. This allows the raw materials to be kneaded more uniformly, and the antistatic agent to be more uniformly dispersed in the base material 4, although this depends on the kneading temperature. As a result, the adhesive tape 100 that satisfies the above-mentioned relational expression can be easily manufactured.

[0151] The upper limit of the kneading time is preferably 20 minutes or less, and more preferably 10 minutes or less, which can suppress denaturation of the raw materials due to heat, although this depends on the kneading temperature.

[0152] As the kneading machine, for example, a screw type kneading extruder or the like is preferably used, and a twin screw type kneading extruder is more preferably used, which allows the raw materials to be kneaded more uniformly.

[0153] The rotation speed of the screw in the screw-type kneading extruder is not particularly limited, but is preferably 5 rpm or more and 100 rpm or less, more preferably 10 rpm or more and 90 rpm or less, and even more preferably 20 rpm or more and 80 rpm or less. This optimizes the shear speed of the raw materials by the screw, and allows the raw materials to be particularly uniformly kneaded. As a result, the uniform dispersion of the antistatic agent in the base material 4 can be particularly improved, and even when the stretching rate is as high as 50% or more, the adhesive tape 100 that satisfies the above-mentioned relational expression can be easily manufactured.

[0154] [2B] Next, an adhesive layer 2 is formed on the upper surface of the base material 4 (see FIG. 6(b)). The surface (upper surface) of the substrate 4 may be subjected to a surface treatment such as corona treatment, chromate treatment, matte treatment, ozone exposure treatment, flame exposure treatment, high-voltage shock exposure treatment, ionizing radiation treatment, primer treatment, or anchor coat treatment in order to improve adhesion between the substrate 4 and the adhesive layer 2.

[0155] In addition, the adhesive layer 2 can be obtained by applying or spraying a liquid material, which is a varnish-like material made by dissolving the resin composition that is the constituent material of the adhesive layer 2 in a solvent, onto the substrate 4, and then evaporating the solvent.

[0156] The solvent is not particularly limited, but examples thereof include methyl ethyl ketone, acetone, toluene, ethyl acetate, dimethylformaldehyde, etc., and one or more of these can be used in combination.

[0157] Furthermore, the liquid material can be applied or sprayed onto the substrate 4 by using methods such as die coating, curtain die coating, gravure coating, comma coating, bar coating, and lip coating.

[0158] [3B] Next, a portion of the adhesive layer 2 formed on the base material 4 is removed so that the center side and the outer periphery side of the adhesive layer 2 are separated. Specifically, a portion of the adhesive layer 2 is removed in an annular shape so that the base material 4 remains. This separates the adhesive layer 2 into a central portion 122 and an outer periphery portion 121 (see FIG. 6(c)).

[0159] An example of a method for removing a portion of the adhesive layer 2 in a circular shape is to punch out a portion surrounding the area to be removed, and then remove the adhesive layer 2 located in the punched out area.

[0160] The region to be removed can be punched out using, for example, a method using a roll-shaped die or a method using a press die. Among these, the method using a roll-shaped die that can continuously produce the pressure-sensitive adhesive tape 100 is preferred.

[0161] The shape of the punched-out portion of the adhesive layer 2 may be any shape as long as the outer circumferential portion 121 of the adhesive layer 2 can be fixed to the wafer ring. Specifically, in addition to a circular shape, it may be an elliptical shape, an oval shape such as a bale shape, a rectangular shape, a polygonal shape such as a pentagon, or the like.

[0162] [4B] Next, the separator 1 is laminated onto the adhesive layer 2 formed on the substrate 4. This results in an adhesive tape 100 in which the adhesive layer 2 is covered with the separator 1 (see FIG. 6(d)).

[0163] The method for laminating the separator 1 on the adhesive layer 2 is not particularly limited, and examples thereof include a lamination method using a roll and a lamination method using a press. Among these, the lamination method using a roll is preferred from the viewpoint of productivity, which allows continuous production.

[0164] The separator 1 is not particularly limited, but examples thereof include a polypropylene film, a polyethylene film, and a polyethylene terephthalate film.

[0165] The surface of the separator 1 may be subjected to a release treatment. Examples of the release treatment include a treatment for coating a release agent, a treatment for providing fine irregularities, etc. Examples of the release agent include silicone-based, alkyd-based, and fluorine-based agents.

[0166] In the method for manufacturing a semiconductor device using the above-mentioned adhesive tape 100, the adhesive tape 100 from which the separator 1 has been peeled off is used.

[0167] Furthermore, when peeling off the separator 1 from the adhesive layer 2 covered with the separator 1, it is preferable to peel off the separator 1 at an angle of 90° or more and 180° or less with respect to the surface of the adhesive layer 2. This can prevent peeling from occurring at any place other than the interface between the adhesive layer 2 and the separator 1.

[0168] Although the pressure-sensitive adhesive tape of the present invention has been described above, the present invention is not limited thereto.

[0169] For example, any component capable of exerting the same function may be added to each layer of the pressure-sensitive adhesive tape of the present invention. In addition, the substrate may have an antistatic layer provided on the surface opposite to the pressure-sensitive adhesive layer.

[0170] Furthermore, the configuration of each layer of the adhesive tape may be replaced with any other layer capable of exerting a similar function, or any other layer may be added thereto.

[0171] Furthermore, in a semiconductor device formed using an adhesive tape, the molded portion may be omitted.

[0172] The adhesive tape may also be used for processing substrates other than semiconductor substrates, such as glass substrates such as soda-lime glass, borosilicate glass, and quartz glass, ceramic substrates such as alumina, silicon nitride, and titanium oxide, resin substrates such as acrylic, polycarbonate, and rubber, and metal substrates. EXAMPLES

[0173] Next, specific examples of the present invention will be described. However, the present invention is not limited to the descriptions in these examples.

[0174] 1. Preparation of raw materials First, the raw materials used in the production of the pressure-sensitive adhesive tapes of each of the Examples and Comparative Examples are shown below.

[0175] (Polyolefin Resin 1) As the polyolefin resin 1, polypropylene (homo PP, manufactured by Sumitomo Chemical Co., Ltd., "FS2011DG-2", MFR2.0) was prepared.

[0176] (Elastomer 1) As elastomer 1, a hydrogenated styrene-based thermoplastic elastomer (SEBS, manufactured by Asahi Kasei Chemicals Corporation, "H1062", styrene content 18% by weight) was prepared.

[0177] (Conductive Materials 1) A polyether-based antistatic agent ("Pelectron PVL" manufactured by Sanyo Chemical Industries, Ltd.) was prepared as the conductive material 1. The conductive material 1 is a material containing a polyolefin / polyether copolymer as a main component.

[0178] (Conductive Materials 2) As the conductive material 2, a polyether-based antistatic agent (manufactured by Sanyo Chemical Industries, Ltd., "Pelectron AS") was prepared. The conductive material 2 is a material whose main component is a polyamide / polyether copolymer.

[0179] (Conductive Material 3) Polythiophene (Arakawa Chemical Industries, Ltd., "Aracoat AS625") was prepared as the conductive material 3. In addition to the conductive material, AS625 contains an acrylic resin as a polymer binder.

[0180] (Base Resin 1) As the base resin 1, an acrylic copolymer was prepared by mixing at least two of butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, acrylic acid, 2-hydroxyethyl acrylate, N,N-dimethylacrylamide, and vinyl acetate, and subjecting the mixture to solution polymerization in a toluene solvent by a conventional method.

[0181] The glass transition point and weight average molecular weight of base resin (acrylic copolymer) 1 were as shown below. Base resin 1 (glass transition temperature: -14°C, weight average molecular weight: 500,000)

[0182] (curable resin 1) As the curable resin 1, dipentaerythritol hexaacrylate (manufactured by Daicel-Allnex Corporation, product number: DPHA), which is an esterification product of (meth)acrylic acid and polyhydric alcohol, was prepared.

[0183] (Crosslinker 1) As the crosslinking agent 1, polyisocyanate (manufactured by Tosoh Corporation, product number: Coronate L) was prepared.

[0184] (Photopolymerization initiator 1) As the photopolymerization initiator 1, benzyl dimethyl ketal (manufactured by Tokyo Chemical Industry Co., Ltd.) was prepared.

[0185] 2. Preparation of Adhesive Tape [Example 1] A resin composition containing polyolefin resin 1 (50.0% by weight), elastomer 1 (30.0% by weight), and antistatic agent 1 (20.0% by weight) was extruded by an extruder to prepare a substrate 4 having a thickness of 150.0 μm. The kneading temperature of substrate 4 was 230° C., the kneading time was 5 minutes, and the screw rotation speed of the kneader was 50 rpm.

[0186] Next, a liquid material containing a resin composition containing base resin 1 (100.0 parts by weight), curable resin 1 (100.0 parts by weight), crosslinking agent 1 (5.0 parts by weight), and photopolymerization initiator 1 (5.0 parts by weight) was prepared. This liquid material was bar-coated on substrate 4 so that the thickness of adhesive layer 2 after drying was 10.0 μm, and then dried at 80° C. for 1 minute to form adhesive layer 2 on the upper surface (one side) of substrate 4, thereby obtaining adhesive tape 100 of Example 1.

[0187] [Examples 2 to 6, Comparative Examples 1 to 4] The adhesive tapes of Examples 2 to 6 and Comparative Examples 1 to 4 were produced in the same manner as in Example 1, except that the constituent materials contained in the resin composition used to form the base material 4 and the constituent materials contained in the resin composition used to form the adhesive layer 2 were those shown in Table 1, and the contents of the constituent materials were changed as shown in Table 1 to form the base material 4 and the adhesive layer 2 with the thicknesses shown in Table 1. The kneading temperature, kneading time, and screw rotation speed for the base material 4 are also shown in Table 1.

[0188] In addition, for the conductive material 3 of Comparative Example 1, the material was bar-coated on the surface of the substrate 4 opposite the adhesive layer 2 so that the thickness of the antistatic layer after drying would be 0.3 μm, and then dried at 80° C. for 10 minutes to form an antistatic layer on the other surface of the substrate 4.

[0189] Furthermore, for the conductive material 3 of Comparative Example 2, the conductive material was bar-coated on the surface of the substrate 4 opposite the adhesive layer 2 so that the thickness of the antistatic layer after drying would be 0.5 μm, and then dried at 80° C. for 10 minutes to form an antistatic layer on the other surface of the substrate 4.

[0190] [Example 7] The adhesive tape of Example 7 was produced in the same manner as in Example 1, except that the substrate 4 was formed as described below.

[0191] That is, polyolefin resin 1 (60.0 wt%) and elastomer 1 (40.0 wt%) were kneaded in a twin-screw kneader to prepare kneaded product 1, and polyolefin resin 1 (50.0 wt%), elastomer 1 (30.0 wt%) and antistatic agent 1 (20.0 wt%) were kneaded in a twin-screw kneader to prepare kneaded product 2. Then, these kneaded products 1 and 2 were extruded into a film shape by a co-extruder to prepare a substrate 4 composed of a laminate in which a first layer having a thickness of 50.0 μm derived from kneaded product 1 and a second layer having a thickness of 50.0 μm derived from kneaded product 2 were laminated. At this time, the kneading temperature, kneading time, and screw rotation speed were adjusted as shown in Table 1 for both kneaded product 1 and kneaded product 2. In addition, the formation of adhesive layer 2 on substrate 4 in the next step was performed on the first layer side of the first layer and the second layer.

[0192] [Example 8] The pressure-sensitive adhesive tape of Example 8 was produced in the same manner as in Example 7, except that the second layer of the substrate 4 was formed to have the thickness shown in Table 1.

[0193] 3. Evaluation The resulting pressure-sensitive adhesive tapes of each of the Examples and Comparative Examples were evaluated by the following methods.

[0194] 3-1. Measurement of the decay time of the charged voltage after the substrate 4 is forcibly charged <1A> First, for each of the adhesive tapes 100 of the Examples and Comparative Examples, test pieces measuring 60 mm in width and 150 mm in length were prepared. Under conditions of 23°C and 50% RH, a charge decay data analyzer ("STATIC DECAY METER MODEL 406C" manufactured by electro-tech systems, inc.) was set so that a voltage was applied in the TD direction to the surface of the substrate 4 of each of the test pieces opposite the adhesive layer 2. The adhesive tape 100 was then forcibly charged to 5000 [V], and the time it took for the charged voltage to decay to 5 [V] was measured as the decay time X [seconds] in an unstretched state (stretch rate 0%).

[0195] <2A> Next, for each of the adhesive tapes 100 of the Examples and Comparative Examples, a test piece measuring 60 mm in width and 150 mm in length was prepared, and the initial adhesive tape 100 (test piece) was stretched 50% from its initial length along the TD at a stretching speed of 50 mm / min under conditions of 23°C and 50% RH with a chuck distance of 100 mm. In this state, the adhesive tape 100 was forcibly charged to 5,000 [V] using the same charge decay data analyzer as above, and the time it took for the charged voltage to decay to 5 [V] was measured as the decay time Y [seconds] when the tape was stretched 50% (stretch rate 50%).

[0196] <3A> Next, for each of the adhesive tapes 100 of the Examples and Comparative Examples, a test piece measuring 60 mm in width and 150 mm in length was prepared, and the chuck distance was set to 100 mm. Under conditions of 23°C and 50% RH, the initial adhesive tape 100 (test piece) was stretched 100% from its initial length along the TD at a stretching speed of 50 mm / min. In this state, the adhesive tape 100 was forcibly charged to 5,000 [V] using the same charge decay data analyzer as above. Thereafter, the time it took for the charged voltage to decay to 5 [V] was measured as the decay time Z1 [seconds] when the tape was stretched 100% (stretch rate 100%).

[0197] <4A> Next, for each of the adhesive tapes 100 of the Examples and Comparative Examples, a test piece measuring 60 mm in width and 150 mm in length was prepared, and the chuck distance was set to 100 mm. Under conditions of 23°C and 50% RH, the initial adhesive tape 100 (test piece) was stretched 250% from its initial length along the TD at a stretching speed of 50 mm / min. In this state, the adhesive tape 100 was forcibly charged to 5,000 [V] using the same charge decay data analyzer as above. Thereafter, the time for the charged voltage to decay to 5 [V] was measured as the decay time Z2 [seconds] when the tape was stretched 250% (stretch rate 250%).

[0198] <5A> In addition, the magnitude of the relation (YX) was calculated based on the measured decay time X and decay time Y.

[0199] 3-2. Evaluation of discharge marks observed on individual pieces <1B> A piece of silicon wafer (manufactured by SUMCO) with a thickness of 0.2 mm and a length of 4 inches was fixed on the adhesive layer 2 of the adhesive tape 100, and the piece was cut so as to reach the middle of the thickness direction of the substrate 4 from the piece, and the piece was divided into individual pieces, thereby forming a plurality of silicon chips (individual pieces) with a length and width of 6 mm. Then, the adhesive layer 2 was exposed to ultraviolet ray illuminance of 55 W / cm. 2 , UV irradiation amount: 200mj / cm 2 The adhesive layer 2 was cured by applying energy through irradiation with ultraviolet light under the conditions above.

[0200] <2B> Next, while the adhesive tape 100 was stretched 8 mm in the planar direction, the individual pieces were pushed up 0.4 mm from the substrate 4 side by four pins each having a tip curvature radius of 100 μm and spaced 4 mm apart, and the silicon chips were picked up by suction with a vacuum collet.

[0201] By going through the above-described steps <1B> and <2B>, picking up of 50 silicon chips was repeatedly carried out for each of the pressure-sensitive adhesive tapes 100 of the Examples and Comparative Examples.

[0202] Then, for each of the adhesive tapes 100 of the Examples and Comparative Examples, the silicon chips obtained were visually inspected for the presence or absence of discharge marks on the silicon chips, and were evaluated according to the following criteria.

[0203] (Evaluation Criteria) ◎: No discharge traces were observed for 50 or 49 silicon chips. ○: No discharge traces were observed for 48 or 47 silicon chips. △: No discharge traces were observed for 40 to less than 47 silicon chips ×: No discharge traces were observed for less than 40 silicon chips The evaluation results thus obtained are shown in Table 1.

[0204] [Table 1]

[0205] As shown in Table 1, the adhesive tape 100 of each embodiment satisfies the relationship YX < 1.0 seconds, and as a result, the amount of change in the tendency of the adhesive tape 100 to become charged due to stretching the adhesive tape 100 is set to be small. As a result, when picking up a silicon chip, the generation of static electricity in the silicon chip is suppressed, and the formation of discharge marks on the silicon chip is suppressed.

[0206] In contrast, the adhesive tapes of each comparative example did not satisfy the relationship YX < 1.0 second. As a result, the amount of change in the tendency of the adhesive tape 100 to become charged due to the stretching of the adhesive tape 100 increased, so that when the silicon chip was picked up, static electricity was generated in the silicon chip, and as a result, discharge marks were observed on the silicon chip. [Explanation of symbols]

[0207] 1 Separator 2 Adhesive layer 4 Base material 7. Semiconductor Substrates 9 Wafer ring 10 Semiconductor device 17 Molded part 20. Semiconductor Chips 21 Terminal 23 Semiconductor chip body 30 Interposer 41 Terminal 70 Bump 80 Sealing layer 81 Connection 85 Solder Bumps 100 Adhesive Tape 121 Outer periphery 122 Center 200 Dicer Table 300 Tables 310 Center 320 Outer periphery 400 Stages 410 Ejector Head 430 Needle

Claims

1. An adhesive tape comprising a substrate and an adhesive layer laminated on one surface of the substrate, the adhesive layer comprising a base resin having adhesive properties as a main material, the adhesive tape being used for temporarily fixing at least one of a substrate and a component, The substrate is a resin material which is a mixture of polypropylene and hydrogenated styrenic thermoplastic elastomer (SEBS); a conductive material which is a permanently antistatic polymer; Including, Under conditions of 23° C. and 50% RH, the adhesive tape is forcibly charged to 5000 [V] in the TD direction, and the time it takes for the charged voltage to decay to 5 [V] is defined as X [seconds]. In a state where the adhesive tape is stretched by 50% in the TD direction, the adhesive tape is forcibly charged to 5,000 [V] in the TD direction, and the time it takes for the charged voltage to decay to 5 [V] is defined as Y [seconds]. An adhesive tape which satisfies Y-X < 1.0 sec.

2. The adhesive tape according to claim 1 , wherein the time period X [seconds] is 1.0 second or less.

3. 3. The adhesive tape according to claim 2, wherein when the adhesive tape is stretched 100% in the TD direction, the adhesive tape is forcibly charged to 5,000 [V] in the TD direction, and the time it takes for the charged voltage to decay to 5 [V] is defined as Z1 [seconds], the time Z1 [seconds] is 5.0 seconds or less.

4. 4. The adhesive tape according to claim 3, wherein when the adhesive tape is stretched 250% in the TD direction, the adhesive tape is forcibly charged to 5,000 [V] in the TD direction, and the time it takes for the charged voltage to decay to 5 [V] is defined as Z2 [seconds], the time Z2 [seconds] is 5.0 seconds or less.

5. An adhesive tape as described in claim 1, wherein the permanent antistatic polymer is mainly composed of a polyolefin / polyether copolymer.

6. The pressure-sensitive adhesive tape according to claim 1 , wherein the base resin is an acrylic resin.

7. The pressure-sensitive adhesive tape according to claim 1 , wherein the content of the conductive material in the base material is 5.0% by weight or more and 45.0% by weight or less.

8. The adhesive tape according to claim 7, wherein the adhesive layer further contains a curable resin that is cured by the application of energy, and the application of energy reduces the adhesive strength of the adhesive layer to at least one of the substrate and the component temporarily fixed on the adhesive layer.

9. The pressure-sensitive adhesive tape according to claim 1 , wherein the substrate has a thickness of 30 μm or more and 200 μm or less.

10. The adhesive tape according to claim 9 , wherein the adhesive layer has a thickness of 5 μm or more and 100 μm or less.

11. 2. The adhesive tape according to claim 1, which is used when, with the substrate fixed on the adhesive layer, the adhesive tape is cut from the substrate to reach partway in the thickness direction of the base material to individualize the substrate to form a plurality of the components, and then, while stretching the adhesive tape in a planar direction, the components are pushed up from the base material side and pulled out from the opposite side of the base material, thereby detaching the components from the adhesive layer.

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