JP5583724B2 - Laser dicing sheet-peeling sheet laminate, laser dicing sheet and chip body manufacturing method - Google Patents

Description

  The present invention relates to a laser dicing sheet that is a dicing sheet used when a laser beam is used in a dicing process for dicing a plate-like member such as a semiconductor wafer, and a laser dicing sheet that is a laminate of the laser dicing sheet and a release sheet. -It is related with the manufacturing method of the chip body obtained by separating a plate-shaped member into pieces using a peeling sheet laminated body and its laser dicing sheet.

  After a circuit is formed on the surface of the semiconductor wafer, a grinding process is performed on the back side of the wafer, and a back grinding process for adjusting the thickness of the wafer and a dicing process for dividing the wafer into a predetermined chip size are performed.

  Along with the recent downsizing of electronic equipment casings and an increase in demand for semiconductor devices using multi-layered chips, semiconductor chips that are constituent members thereof are being made thinner. For this reason, it has been required to reduce the thickness of a conventional wafer having a thickness of about 350 μm to 50 to 100 μm or less.

  As the wafer that is a brittle member becomes thinner, the risk of breakage increases during processing and transportation. When such an ultra-thin wafer is cut by a dicing blade that rotates at high speed, chipping or the like occurs particularly on the back side of the semiconductor wafer, and the die strength of the chip is significantly reduced.

  For this reason, a so-called stealth dicing method is proposed in which a dicing line is formed while a modified portion is selectively formed by irradiating the inside of a semiconductor wafer with a laser beam, and the semiconductor wafer is cut starting from the modified portion. (Patent Document 1). According to the stealth dicing method, a laser beam is irradiated on the inside of a semiconductor wafer to form a modified portion, and then an ultrathin semiconductor wafer is attached to an adhesive sheet composed of a base material and an adhesive layer, and the adhesive sheet is expanded. Thus, the semiconductor wafer can be divided (diced) along the dicing line, and semiconductor chips can be produced with a high yield.

  A laser may be used as a processing means in the dicing process as described above, and a laser may be used as a tool for accurately aligning a plate-like member such as a semiconductor wafer during the dicing process. In these cases, a dicing sheet (also referred to as “laser dicing sheet” in the present specification) used when laser light is used in the dicing process allows the laser to pass through the laser dicing sheet. Therefore, it must have excellent transparency to the laser.

  In order to meet such a demand, for example, Patent Document 2 discloses a base resin film and a pressure-sensitive adhesive sheet in which a pressure-sensitive adhesive layer is formed on the base resin film, and parallel rays in a wavelength region of 400 to 1100 nm. A wafer sticking pressure-sensitive adhesive sheet having a transmittance of 80% or more is disclosed, and in a preferred embodiment of the sheet, the arithmetic average roughness Ra of the surface opposite to the surface on which the pressure-sensitive adhesive layer of the base resin film is formed is 0.1 to 0.3 μm.

Japanese Patent No. 3762409 JP 2012-15236 A

  As disclosed in Patent Document 2, making the surface opposite to the surface on which the adhesive layer of the base resin film is formed as a smooth surface has advantages such as improving dicing workability for the laser dicing sheet. . However, when the surface opposite to the side facing the pressure-sensitive adhesive layer of the base material of the laser dicing sheet (also referred to as “back surface of the base material” in this specification) is a smooth surface, the following problems may occur. It was revealed.

  That is, generally, the pressure-sensitive adhesive layer of the laser dicing sheet is on the surface opposite to the side facing the base material (the surface on which the plate-like member is pasted during use) until it is used in the dicing process. The release surface of the release sheet is affixed so that the adhesive layer is not contaminated or deteriorated. The laser dicing sheet-release sheet laminate (also referred to as “DR laminate” in this specification), which is a laminate of the laser dicing sheet and the release sheet thus obtained, is stored in various forms. For example, in some cases, a plurality of laser dicing sheets may be stored in the form of an elongated body that is laminated on the release surface of a long release sheet in a direction parallel to the longitudinal direction of the release sheet. In some cases, the long body is wound in the longitudinal direction and stored in the form of a wound body. In some cases, for example, a single laser dicing sheet may be stored in the form of a stack obtained by stacking a number of layers of a DR laminate formed by attaching a single release sheet.

  When the DR laminate is stored in the form of a wound body or a stack, the back surface of the substrate of the laser dicing sheet of the DR laminate, and the release sheet peeling surface of another DR laminate closest to the DR laminate, Is in contact with the opposite surface (also referred to as “releasable sheet back surface” in this specification). Depending on the storage state (specifically, when the winding force of the winding body is strong or when the stack body is pressed in the stacking direction, etc.) In some cases, the adhesion between the back surface of the release sheet of another DR laminate that is in contact with the back surface may be increased.

  As a specific example, a problem when the adhesion is increased will be described by taking a wound body in which a DR laminated body having a long shape is wound so that the laser dicing sheet is on the inner side. When the DR laminate is unwound from the winding body, the release sheet in the outermost layer is pulled, and the laser dicing sheet that is attached to the release surface located on the inner peripheral side (core side) of the release sheet is also the outermost periphery. The unwinding operation is normally performed by being unwound from the winding body together with the release sheet. However, when the adhesion between the back surface of the base material and the back surface of the release sheet of the DR laminate located on the inner circumference side in the winding body is high, the laser dicing sheet that should be fed out originally is that of the laser dicing sheet. Peeling occurs at the interface between the pressure-sensitive adhesive side surface and the release surface of the outermost release sheet. As a result, the laser dicing sheet is not fed out together with the outermost release sheet, but remains on the back surface of the release sheet of the DR laminate located on the inner peripheral side.

  When such a situation occurs, since the laser dicing sheet is peeled off from the DR laminated body that has been fed out, it is not possible to carry out the pasting operation between the laser dicing sheet and the plate-like member. Furthermore, the laser dicing sheet attached to the back surface of the release sheet of the DR laminate may significantly reduce the workability of the subsequent release sheet winding operation. Specifically, it is exemplified that the sheet is wound around a pinch roller for winding the release sheet. In such a case, the feeding operation of the DR laminated body in the form of a wound body must be stopped. Hereinafter, such a problem is also referred to as “DR laminate supply failure”.

  The same DR laminate supply failure may occur in a DR laminate in the form of a stack. In the case of a DR laminate having a laser dicing sheet attached to the lower layer side of the release sheet, the DR laminate is obtained by holding the release sheet in the same manner as the DR laminate in the form of the winding body. When turning off, only the release sheet is turned off, and the laser dicing sheet may remain in the stack. In the case of a stack of DR laminates in which a laser dicing sheet is attached to the upper layer side of the release sheet, when the DR laminate is turned over by grasping the release sheet, the laser dicing of the lower DR laminate is performed. There may be a problem that the sheet is also flipped together.

  The present invention relates to a laser dicing sheet capable of reducing the possibility of a DR laminate supply failure occurring in a DR laminate in the form of such a wound body or stack, and lamination of the laser dicing sheet and a release sheet. It is an object to provide a chip body manufacturing method for manufacturing a chip body by dividing a plate-like member into pieces using a laser dicing sheet-peeling sheet stack body (DR stack body), and the laser dicing sheet. To do.

  In order to achieve the above object, the findings obtained by the present inventors are as follows. The laser dicing sheet provided in the DR laminate is pasted up to the time when the release sheet is pasted with the peeled surface facing, and the pressure-sensitive adhesive layer having the surface to which the plate-like member is stuck at the time of use, and the above-mentioned pressure-sensitive adhesive layer A part of the surface opposite to the side facing the pressure-sensitive adhesive layer (in this specification, part of the surface is also referred to as “region”) is a laser when in use. The first sheet serving as the incident surface of the first sheet, and the second sheet laminated in a region where the laser is not irradiated when used on the surface opposite to the side facing the adhesive layer of the first sheet. . Accordingly, the release sheet of the release sheet included in the DR laminate on the surface opposite to the first sheet in the second sheet (corresponding to a part of the back surface of the base material of the laser dicing sheet). Adhesion to the back surface can be appropriately controlled. Specifically, by making the peeling force of the surface of the second sheet opposite to the side facing the first sheet to the surface opposite to the peeling surface of the release sheet be 50 mN / 50 mm or less. The present inventors have found that the above-mentioned DR laminate supply failure is less likely to occur.

  The present invention completed on the basis of such knowledge is firstly laminated on the first sheet, the second sheet laminated on one side of the first sheet, and the other side of the first sheet. Laser dicing sheet-release sheet laminate provided with a laser dicing sheet provided with the adhesive layer and a release sheet laminated so that the release surface faces the adhesive layer side surface of the laser dicing sheet The first sheet has a Young's modulus at 23 ° C. of not less than 30 MPa and not more than 600 MPa, and the arithmetic average roughness Ra of one surface of the first sheet is less than 0.1 μm, The second sheet has an annular shape in plan view, and the in-ring exposed area where the second sheet is not stacked is surrounded by the second sheet in plan view on one surface of the first sheet. The laser dicing sheet includes a region that is irradiated with a laser, and the release surface of the release sheet has a region where the laser dicing sheet is not laminated, on the one surface of the second sheet For the stack obtained by placing the surface opposite to the release surface of the release sheet, a load of 19.6 N was applied from the release surface side of the test release sheet in an environment of 40 ° C. and a relative humidity of 80%. When applied for 1 hour, further left standing for 1 hour under no load in an environment of 23 ° C. and 50% relative humidity, and peeled off the test release sheet of the stack after standing 180 ° The laser dicing sheet-peeling sheet laminate is provided in which the peeling force measured in (1) is 50 mN / 50 mm or less (Invention 1).

  The base of the laser dicing sheet is composed of two types of sheets, one having a small arithmetic average roughness Ra and one adjusted so as to reduce the adhesion to the back of the release sheet. It is realized that the adhesiveness between the back surface of the material and the back surface of the release sheet is excessively increased and the problem that they are difficult to peel off is less likely to occur.

  In the above invention (Invention 1), the first sheet has a linear transmittance of 80% or more at a wavelength of 1064 nm and a phase difference at a wavelength of 1064 nm at least in a portion irradiated with a laser when using a laser dicing sheet. Is preferably 100 nm or less (Invention 2). In such a case, when the laser beam that has passed through the first sheet at the time of use is condensed in the plate-like member, as in stealth dicing, the energy of the irradiated laser is efficiently contained in the plate-like member. Therefore, dicing can be performed more appropriately.

  In the said invention (invention 1 and 2), it is preferable that the surface on the opposite side to the side which opposes the said 1st sheet | seat in the said 2nd sheet | seat has arithmetic mean roughness Ra of 0.3 micrometer or more (invention 3). ). Thus, it becomes easy to make said peeling force into 50 mN / 50 mm or less by making the area | region comprised from a 2nd sheet | seat into the rough surface among the base-material back surfaces of a laser dicing sheet.

  In the said invention (invention 1 to 3), it is preferable that the surface on the opposite side to the side which opposes the said 1st sheet | seat in the said 2nd sheet | seat consists of the surface of a polyester-type film (invention 4). By making the area | region comprised from a 2nd sheet | seat into the surface which consists of a polyester-type film among the base-material back surfaces of a laser dicing sheet, it becomes easy to make said peeling force into 50 mN / 50mm or less. Since the polyester film contains a resin material containing an aromatic compound and is relatively rigid, the adhesion to the back surface of the release sheet is difficult to increase, but such a material is used during laser light, particularly stealth dicing. In order to absorb the light of 1064 nm used, it was difficult to use as a base-material constituent material in the laser dicing sheet whose base material is a single layer.

  In the said invention (invention 1 to 4), it is preferable that the said peeling sheet is a polyester film which apply | coated the release agent (invention 5). Polyester film is a relatively rigid material, so it is also a preferred material for the release sheet substrate. However, it does not have releasability for adhesive, so it can be peeled off by applying a release agent to one side of the polyester film. It is preferable to form a layer and to use the surface of the release layer as the release surface of the release sheet.

  In the above inventions (Inventions 1 to 5), the release sheet is a long body, and a plurality of the laser dicing sheets are arranged apart from each other in the longitudinal direction of the release sheet and wound in the longitudinal direction. It is preferable to have the form of the wound body (Invention 6). In such a form, it is excellent in handling at the time of storage, and it is easy to automate the peeling operation at the time of use.

  A second aspect of the present invention is a laser dicing sheet obtained by peeling the release sheet from the laser dicing sheet-release sheet laminate according to any one of the above inventions (Inventions 1 to 6), wherein the pressure-sensitive adhesive A region overlapping the exposed region in the ring of the first sheet on the surface opposite to the side facing the first sheet of the layer in a plan view is pasted with a plate-like member when the laser dicing sheet is used. A laser dicing sheet characterized in that it includes a region (Invention 7).

  When such a laser dicing sheet is irradiated with a laser so as to pass through the laser dicing sheet to a plate-like member attached at the time of use, the laser is scattered or the uniformity of the phase is lowered. The problem is less likely to occur.

  In the above invention (Invention 7), the radius of the inscribed circle in plan view of the in-ring exposed region of the first sheet is greater than the radius of the circumscribed circle in plan view of the region to which the plate member is attached. Is preferably 2 mm or more (Invention 8). By having the relationship between the in-ring exposed region and the plate-like member, workability when attaching the plate-like member to the laser dicing sheet is improved, and the region not included in the in-ring exposed region is seen in plan view. The possibility that the plate-like member is stuck is further reduced.

  The present invention thirdly, in a predetermined region of the surface opposite to the side facing the first sheet in the pressure-sensitive adhesive layer of the laser dicing sheet according to any of the above inventions (Inventions 7 and 8), The plate-like member is affixed so that the first sheet and the pressure-sensitive adhesive layer are transmitted to the plate-like member with the exposed area in the ring of the first sheet of the laser dicing sheet as an incident surface. The plate member is separated into individual pieces by extending the laser dicing sheet, which is attached to the plate member after the laser irradiation, and extending in the main surface direction. A chip body manufacturing method is provided (Invention 9).

  According to such a manufacturing method, since the modified portion is appropriately formed inside the plate-like member by the laser beam that has passed through the laser dicing sheet and entered, the modified portion is expanded by the expanding process of extending the laser dicing sheet. It is more stable that the plate member is broken at the portion. Therefore, according to the manufacturing method of the present invention, the chip body can be manufactured with a high yield.

  In the laser dicing sheet provided in the DR laminate according to the present invention, the region irradiated with the laser during use is composed of a surface opposite to the side facing the pressure-sensitive adhesive layer of the first sheet. For this reason, the problem that the laser beam is scattered when the laser is irradiated in the dicing process hardly occurs. On the other hand, the laser dicing sheet provided in the DR laminate according to the present invention is a state in which the DR laminate before use is laminated (specifically, in the form of a winding body or in the form of a stack body). The surface of the DR laminate that is in contact with the back surface of the release sheet is mainly the side of the second sheet that faces the first sheet of the second sheet that is set to have low adhesion to the back surface of the release sheet. This is the opposite surface (the back surface of the second sheet). For this reason, when a certain DR laminate is peeled off from the release sheet arranged so that the back side of the release sheet is in contact with the back side of the second sheet, the DR laminate becomes the back side of the second sheet and the release sheet. The possibility of peeling between the pressure-sensitive adhesive layer of the laser dicing sheet and the peeling surface of the peeling sheet is reduced without peeling between the back surface and the back surface. Therefore, even if the DR laminated body according to the present invention is in the form of a wound body or a stacked body, defective supply of the DR laminated body is unlikely to occur.

It is a schematic sectional drawing of the laser dicing sheet-release sheet laminated body (DR laminated body) which concerns on one Embodiment of this invention. The laser dicing sheet-release sheet laminate (DR laminate) according to an embodiment of the present invention is in the form of a wound body, and a perspective view conceptually showing a state in which the DR laminate is drawn out from the wound body. FIG. It is sectional drawing which shows notionally the state in which the laser dicing sheet-release sheet laminated body (DR laminated body) which concerns on one Embodiment of this invention has comprised the form of the stack body. The partial cross section which shows notionally the state just before taking out one piece of the laser dicing sheet which the DR laminated body is drawn | fed out from the winding body which concerns on one Embodiment of this invention, and is sticking to the elongate peeling sheet FIG. It is sectional drawing which shows notionally the method of evaluating the adhesiveness with respect to the peeling sheet back surface of the peeling sheet of the surface on the opposite side to the 1st sheet | seat in the 2nd sheet | seat of the laser dicing sheet concerning this embodiment. (A) is sectional drawing which shows notionally the stacked body by which the 2nd sheet | seat is laminated | stacked on the flat plate made from SUS, and the peeling sheet is piled up on the 2nd sheet | seat, (b) is this weighting. It is sectional drawing which shows notionally the state which is applying the load to a stack. It is sectional drawing which shows notionally the state by which the plate-shaped member and the ring frame were affixed on the adhesive layer of the laser dicing sheet which concerns on this embodiment.

  Hereinafter, embodiments of the present invention will be described.

1. Laser dicing sheet-release sheet laminate As shown in FIG. 1, a laser dicing sheet-release sheet laminate (DR laminate) 100 according to an embodiment of the present invention includes a first sheet 1 and a first sheet. A laser dicing sheet 10 including a second sheet 2 laminated on one side of the first layer, and an adhesive layer 3 laminated on the other side of the first sheet, and the pressure-sensitive adhesive layer 3 side of the laser dicing sheet 10 And a release sheet 11 laminated so that the release surface faces the surface. In the following description, the first sheet 1 and the second sheet 2 may be collectively referred to as a base material.

(1) 1st sheet The 1st sheet | seat 1 of the dicing sheet 10 with which the DR laminated body 100 which concerns on this embodiment is provided has the function to permeate | transmit a laser in a dicing process, the expansion process performed after a dicing process, etc. The material is not particularly limited as long as it does not break. Usually, it is composed of a film mainly composed of a resin-based material. Specific examples of the film include: a polyvinyl chloride film, a vinyl chloride copolymer film, a polyethylene film such as a high density polyethylene (HDPE) film, a stretched or unstretched polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, A polyurethane film, an ethylene vinyl acetate copolymer film, and a film made of a water additive or a modified product thereof are used. In addition, these crosslinked films and copolymer films are also used, and among them, a polyvinyl chloride film is preferable in consideration of expandability. The above substrate may be a single type, or may be a laminated film in which two or more types are combined.

  The first sheet 1 may contain various additives such as pigments, flame retardants, plasticizers, antistatic agents, lubricants, fillers, etc., in a film mainly composed of the above-mentioned resin material. The content of such additives is not particularly limited, but should be limited to a range where the first sheet 1 exhibits a desired function and does not lose smoothness and flexibility. As described above, one part of the first sheet 1 is partly a laser incident surface when in use, so a material (pigment, filler, etc.) that reduces the linear transmittance of the incident laser is used. It is preferable not to contain.

  In the case where the pressure-sensitive adhesive layer 3 contains a material that is polymerized by irradiation with energy rays, and ultraviolet rays are used as the energy rays to be polymerized, the first sheet 1 has transparency to the ultraviolet rays. It is preferable. In addition, when using an electron beam as said energy beam, it is preferable that the 1st sheet | seat 1 has the transmittance | permeability with respect to an electron beam.

  Moreover, in order to improve adhesiveness with the adhesive which comprises the adhesive layer 3, in the surface by which the adhesive layer 3 in the 1st sheet | seat 1 is laminated | stacked, a corona treatment is given or a primer layer is provided. It may be provided.

  The Young's modulus at 23 ° C. of the first sheet 1 is 30 MPa to 600 MPa, preferably 50 MPa to 500 MPa, and more preferably 100 MPa to 400 MPa. Since the first sheet 1 having a Young's modulus at 23 ° C. of 30 MPa or more and 600 MPa or less is easily stretched uniformly during the expanding process, the plate shape on the laser dicing sheet 10 is adopted when the stealth dicing method is adopted. Inconveniences such as variations in the alignment direction of the chip bodies formed by cutting the members appropriately or by cutting the plate-like member are unlikely to occur.

  Further, the breaking elongation of the first sheet 1 is preferably 50% or more as a value measured by stretching at 200 mm / min at 23 ° C. and a relative humidity of 50%, and is 70% or more. Is more preferable, and 100% or more is particularly preferable. Here, the breaking elongation is an elongation ratio of the length of the test piece at the time of breaking the test piece to the original length in a tensile test based on JIS K7161: 1994 (ISO 527-1: 1993). Since the first sheet 1 having a breaking elongation of 50% or more is not easily broken during the expanding process, the plate-like member on the laser dicing sheet 10 is not properly cut or the plate-like member is divided. It is difficult for the chip body to fall off.

  The planar view shape of the first sheet 1 (the shape viewed from the direction parallel to the normal to the main surface) is a plate-like member such as a semiconductor wafer that is a workpiece on the pressure-sensitive adhesive layer 3 side of the laser dicing sheet 10. When affixed to the area including the center of the surface, a sufficient area is secured around the ring frame used for transportation around the area, and the area affixed to these semiconductor wafers and the ring frame are secured. A plurality of chips obtained by securing a suitable area between the pasted area and attaching a jig as a fulcrum when pulling down the ring frame in the expanding process, and separating the jig and the semiconductor wafer. The shape is not particularly limited as long as a certain gap (several millimeters to several centimeters) is set in a plan view even after being stretched between the body and the body. Usually, the plan view shape of the first seat 1 is a shape close to a circle corresponding to the shape created by the inner periphery of the ring frame.

  Of the main surface of the first sheet 1, the surface roughness of the side irradiated with laser during use (hereinafter also referred to as “back surface”) is at least a laser during use from the viewpoint of enhancing the laser transmittance. As for the region irradiated with (hereinafter also referred to as “laser irradiation region”), the arithmetic average roughness Ra is 0.1 μm or less. Here, the arithmetic average roughness Ra is a characteristic based on JIS B0601: 2001, measured by a contact-type surface roughness meter, and the same applies hereinafter. When satisfying the condition of such surface roughness, the laser is hardly scattered in the first sheet 1 and the linear transmittance of the first sheet 1 is not easily lowered. The first sheet 1 preferably has a linear transmittance of 80% or more at a wavelength of 1064 nm of a light source used for stealth dicing from the viewpoint of improving the processing quality and processing accuracy of the dicing process, and is preferably 90% or more. More preferred. By setting the arithmetic average roughness Ra in the laser irradiation region on the back surface of the first sheet 1 to a value within the above-described range, the linear transmittance can be easily adjusted to such a range, and is preferably 0.08 μm or less. . Since the laser transmittance increases as the arithmetic average roughness Ra decreases, the arithmetic average roughness Ra in the laser irradiation region on the back surface of the first sheet 1 is preferably as small as possible, and the lower limit thereof is not particularly limited. This arithmetic average roughness Ra usually has a lower limit of about 0.01 μm due to manufacturing limitations of the members constituting the back surface of the first sheet 1. The arithmetic mean roughness Ra of the back surface of the first sheet 1 can be adjusted by a known method. For example, when producing a film that gives the first sheet 1 by extrusion molding, the surface shape of the cooling roll is transferred. In the production of the film that gives the first sheet 1 that is a stretched film, it can be performed by changing the amount and size of the filler added to the material of the film, casting the liquid, In the case of obtaining a film by curing, it can be carried out by adjusting the roughness of the process film used for casting.

  The thickness of the 1st sheet | seat 1 is not limited as long as the laser dicing sheet 10 can function appropriately in the above-mentioned dicing process and an expanding process. If it is excessively thin, there is a concern that it may be easily broken during the manufacturing process or use. On the other hand, it is preferable that the first sheet 1 has a phase difference at a wavelength of 1064 nm of a light source used for stealth dicing of 100 nm or less from the viewpoint of improving the processing quality and processing accuracy of the dicing process. If it is excessively thick, there is a concern that it will be difficult to set the above phase difference to 100 nm or less even if the material of the first sheet 1 is adjusted. Therefore, the thickness of the first sheet 1 is preferably 20 μm or more and 150 μm or less, more preferably 40 μm or more and 100 μm or less, and particularly preferably 50 μm or more and 90 μm or less.

(2) Pressure-sensitive adhesive layer The pressure-sensitive adhesive layer 3 can be formed of various conventionally known pressure-sensitive adhesives. Such an adhesive is not limited at all, but, for example, an adhesive such as rubber-based, acrylic-based, silicone-based, or polyvinyl ether is used. Moreover, an energy ray polymerization type, a heat foaming type, or a water swelling type pressure sensitive adhesive can also be used. As the energy ray (ultraviolet ray, electron beam, etc.) polymerizable adhesive, it is particularly preferable to use an ultraviolet polymerizable adhesive.

Hereinafter, the energy ray polymerization type pressure-sensitive adhesive will be specifically described with an acrylic pressure-sensitive adhesive as an example.
The acrylic pressure-sensitive adhesive contains an acrylic polymer (A) in order to give sufficient pressure-sensitive adhesiveness and film-forming property (sheet processability) to the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition, and energy rays. Contains a polymerizable compound (B). The energy ray polymerizable compound (B) also contains an energy ray polymerizable group and polymerizes when irradiated with energy rays such as ultraviolet rays and electron beams, and has a function of reducing the adhesive strength of the pressure sensitive adhesive composition. Moreover, as what combines the property of said component (A) and (B), it replaces with these, and energy-beam polymerization type polymer (henceforth, component (A AB) may be used. Such an energy beam polymerization type pressure-sensitive adhesive polymer (AB) has a property that has both the function of imparting adhesiveness and film-forming property and energy beam polymerizability.

  A conventionally well-known acrylic polymer can be used as an acrylic polymer (A). The weight average molecular weight (Mw) of the acrylic polymer (A) is preferably 100,000 to 2,000,000, and more preferably 300,000 to 1,500,000. Moreover, it is preferable that molecular weight distribution (Mw / Mn, Mn is a number average molecular weight) is 1.0-10, and it is more preferable that it is 1.0-3.0. The glass transition temperature (Tg) of the acrylic polymer (A) is preferably in the range of −70 to 30 ° C., more preferably in the range of −60 to 20 ° C.

  As specific examples of (meth) acrylic acid ester that is a monomer for forming the acrylic polymer (A), as specific examples of (meth) acrylic acid ester, methyl (meth) acrylate, ethyl (meth) acrylate, Alkyl (meth) acrylates having 1 to 18 carbon atoms in the alkyl group such as propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate; cycloalkyl (meth) acrylate, benzyl (meth) acrylate (Meth) acrylates having a cyclic skeleton such as isobornyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, imide acrylate; 2-hydroxyethyl (meth) acrylate, 2- Having a hydroxyl group such as mud hydroxypropyl (meth) acrylate (meth) acrylate; glycidyl methacrylate, (meth) acrylate having an epoxy group such as glycidyl acrylate. In addition, examples of the monomer for forming the acrylic polymer (A) include acrylic acid, methacrylic acid, itaconic acid, and acrylonitrile. The acrylic polymer (A) may be copolymerized with vinyl acetate, styrene, vinyl acetate or the like.

  The energy beam polymerizable compound (B) is a compound that polymerizes when irradiated with energy rays such as ultraviolet rays and electron beams. Examples of the energy beam polymerizable compound include low molecular weight compounds (monofunctional and polyfunctional monomers and oligomers) having an energy beam polymerizable group, and specifically include trimethylolpropane triacrylate and tetramethylolmethane. Tetraacrylate, pentaerythritol triacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate or 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, dicyclopentadiene dimethoxydiacrylate, isobornyl Cyclic aliphatic skeleton-containing acrylate such as acrylate, polyethylene glycol diacrylate, oligoester acrylate, urethane acrylate oligomer, Carboxy-modified acrylates, polyether acrylates, acrylate compounds such as itaconic acid oligomer is used. Such a compound has at least one polymerizable double bond in the molecule, and usually has a molecular weight of about 100 to 30,000, preferably about 300 to 10,000.

  Generally, the component (B) is used in a proportion of 10 to 400 parts by weight, preferably about 30 to 350 parts by weight, relative to 100 parts by weight of the component (A).

  The energy beam polymerization type pressure-sensitive adhesive polymer (AB) having the properties of the components (A) and (B) is formed by bonding an energy beam polymerizable group to a main chain or a side chain.

  The main skeleton of the energy beam polymerization type polymer (AB) is not particularly limited, and can be the same as the above-mentioned acrylic polymer (A).

  The energy beam polymerizable group bonded to the main chain or side chain of the energy beam polymerization type polymer (AB) is, for example, a group containing an energy beam polymerizable carbon-carbon double bond, specifically, (meth). An acryloyl group etc. can be illustrated. The energy beam polymerizable group may be bonded to the energy beam polymerization type pressure-sensitive adhesive polymer via an alkylene group, an alkyleneoxy group, or a polyalkyleneoxy group.

  The weight average molecular weight (Mw) of the energy beam polymerization type polymer (AB) is preferably 100,000 to 2,000,000, and more preferably 300,000 to 1,500,000. Moreover, it is preferable that molecular weight distribution (Mw / Mn, Mn is a number average molecular weight) is 1.0-10, and it is more preferable that it is 1.0-3.0. The glass transition temperature (Tg) of the energy beam polymerization type polymer (AB) is preferably in the range of −70 to 30 ° C., more preferably in the range of −60 to 20 ° C.

  The energy ray polymerization type polymer (AB) includes, for example, an acrylic polymer containing a functional group such as a hydroxyl group, a carboxyl group, an amino group, a substituted amino group, and an epoxy group, a substituent that reacts with the functional group, and It is obtained by reacting a polymerizable group-containing compound having 1 to 5 energy beam polymerizable carbon-carbon double bonds per molecule. Such an acrylic polymer includes a (meth) acrylic acid ester monomer having a functional group such as a hydroxyl group, a carboxyl group, an amino group, a substituted amino group, and an epoxy group or a derivative thereof, and a monomer constituting the component (A) described above. And obtained by copolymerization. The polymerizable group-containing compound includes (meth) acryloyloxyethyl isocyanate, meta-isopropenyl-α, α-dimethylbenzyl isocyanate, (meth) acryloyl isocyanate, allyl isocyanate, glycidyl (meth) acrylate; Acrylic acid etc. are mentioned. In the energy ray polymerization type polymer (AB) obtained by such a production method, the weight average molecular weight (Mw), molecular weight distribution (Mw / Mn), glass transition temperature (Tg) of the above-mentioned energy ray polymerization type polymer (AB). ) Refers to that of an acrylic polymer before being reacted with the polymerizable group-containing compound.

  It is preferable to use a photopolymerization initiator in combination with the energy beam polymerizable compound (B) or the energy beam polymerization type polymer (AB). Examples of photopolymerization initiators include photoinitiators such as benzoin compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, thioxanthone compounds, and peroxide compounds, and photosensitizers such as amines and quinones. 1-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyl diphenyl sulfide, tetramethyl thiuram monosulfide, azobisisobutyronitrile, dibenzyl, diacetyl, β-chloranthraquinone Examples include 2,4,6-trimethylbenzoyldiphenylphosphine oxide. By using the photopolymerization initiator in combination, when ultraviolet rays are used as energy rays, the irradiation time and the irradiation amount can be reduced by blending the photopolymerization initiator. Although the compounding quantity of this photoinitiator is not specifically limited, With respect to a total of 100 parts by mass (solid content, the same shall apply hereinafter) of the energy beam polymerizable compound (B) and the energy beam polymerizable adhesive polymer (AB), It is preferable to set it as 0.5 to 10 mass parts.

  Furthermore, in order to improve various physical properties, the pressure-sensitive adhesive composition may contain other components (such as a crosslinking agent) as necessary. Examples of the crosslinking agent include organic polyvalent isocyanate compounds, organic polyvalent epoxy compounds, and organic polyvalent imine compounds. Although the compounding quantity of this crosslinking agent is not specifically limited, It shall be 0.2 mass part or more and 10 mass parts or less with respect to a total of 100 mass parts of an acryl-type polymer (A) and an energy beam polymerization type polymer (AB). It is preferable.

  The acrylic pressure-sensitive adhesive containing the acrylic polymer (A) and the energy beam polymerizable compound (B) as described above or the acrylic pressure-sensitive adhesive containing the energy beam polymerization-type pressure-sensitive polymer (AB) is irradiated with energy rays. To polymerize. Examples of energy rays include ionizing radiation, that is, X-rays, ultraviolet rays, electron beams, and the like. Among these, ultraviolet rays that are relatively easy to introduce irradiation equipment are preferable.

When ultraviolet rays are used as the ionizing radiation, near ultraviolet rays including ultraviolet rays having a wavelength of about 200 to 380 nm may be used for ease of handling. What is necessary is just to select suitably according to the kind of energy-beam polymeric compound (B) and the thickness of the adhesive layer 3, and it is about 50-500 mJ / cm < ² > normally, and the amount of ultraviolet rays is 100-450 mJ / cm < ² >. 200 to 400 mJ / cm ² is more preferable. Moreover, ultraviolet illuminance is about 50-500 mW / cm < ² > normally, 100-450 mW / cm < ² > is preferable and 200-400 mW / cm < ² > is more preferable. There is no restriction | limiting in particular as an ultraviolet-ray source, For example, a high pressure mercury lamp, a metal halide lamp, UV-LED etc. are used.

  When an electron beam is used as the ionizing radiation, the acceleration voltage may be appropriately selected according to the type of the energy beam polymerizable compound (B) and the thickness of the pressure-sensitive adhesive layer 3, and usually an acceleration voltage of 10 to 1000 kV. It is preferable that it is a grade. Moreover, what is necessary is just to set an irradiation dose to the range which an energy-beam polymeric compound (B) superposes | polymerizes appropriately, and is normally selected in the range of 10-1000 krad. The electron beam source is not particularly limited, and for example, various electron beam accelerators such as a Cockloft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type are used. be able to.

  The thickness of the pressure-sensitive adhesive layer 3 is preferably in the range of 1 μm to 15 μm, more preferably 2 μm to 10 μm, and particularly preferably 3 μm to 8 μm. When the pressure-sensitive adhesive layer 3 is excessively thick, even if the material and thickness of the first sheet 1 are controlled, it is transmitted through the laminate of the first sheet 1 and the pressure-sensitive adhesive layer 3 during use. It may be difficult to make the intensity and phase uniformity of the laser reaching the member within a desired range. In addition, when the laser dicing sheet-release sheet laminate according to the present invention is used for the stealth dicing method, if the pressure-sensitive adhesive layer 3 is thick, the deformation of the base material at the time of expansion does not easily propagate to the semiconductor wafer. There is a concern that this may cause a problem in the division. If the pressure-sensitive adhesive layer 3 is excessively thin, the pressure-sensitive adhesive layer may not be able to properly fix the plate-like member during use.

(3) Release Sheet The DR laminate 100 according to the present embodiment has a surface opposite to the side facing the first sheet 1 of the pressure-sensitive adhesive layer 3 of the laser dicing sheet 10 (a plate-like member is pasted during use). The release sheet 11 is laminated on the surface) in order to protect the adhesive layer until it is used.

  As long as the above object can be achieved, the material constituting the release sheet 11 is arbitrary, and examples include a support film made of a plastic film and a release agent applied thereto. Specific examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, and polyolefin films such as polypropylene and polyethylene. Among these, a polyester film having low stretchability and excellent dimensional stability and smoothness is preferable. As the release agent, silicone-based, fluorine-based, long-chain alkyl-based, and the like can be used, and among these, a silicone-based material that is inexpensive and provides stable performance is preferable. The plastic film that forms the support film for the release sheet 11 may function alone as a release sheet. That is, the peeling surface may be comprised from the surface of this support film. When the support film is a polyester film, it usually does not have releasability with respect to the pressure-sensitive adhesive as it is, so that it is preferable to apply a release agent to form a release surface. Alternatively, instead of the support film made of the plastic film of the release sheet 11 described above, a paper base such as glassine paper, coated paper, or high-quality paper or a laminated paper obtained by laminating a thermoplastic resin such as polyethylene on a paper base is used. Also good. Although there is no restriction | limiting in particular about the thickness of the peeling sheet 11, Usually, it is about 20 micrometers or more and 250 micrometers or less.

  The shape of the release sheet 11 is not particularly limited, but the pressure-sensitive adhesive layer 3 of the laser dicing sheet 10 is usually provided on the release surface of the release sheet 11 so that the laser dicing sheet 10 can be easily peeled from the release sheet 11. An area where the side surface is not attached is provided.

  An example of a specific shape of the release sheet 11 is a long shape. A specific example of the form of the DR laminate 100 in this case is a form in which a plurality of laser dicing sheets 10 are attached to the release surface of the release sheet 11 while being separated from each other in the longitudinal direction of the release sheet 11. At this time, the DR laminate 100 may be stored as a long body. However, as shown in FIG. 2, one end of the DR laminate 100 in the longitudinal direction is fixed to the core material C and wound. And may be stored in the form of a wound body 100A. FIG. 2 is a perspective view conceptually showing a state in which the DR laminated body 100 in the form of such a wound body 100A is drawn out.

  Another example of the specific shape of the release sheet 11 is a non-long shape. A specific example of the form of the DR laminate 100 in this case is a form in which one laser dicing sheet 10 is attached to the release sheet 11. At this time, as shown in FIG. 3, the DR laminate 100 may be stored in the form of a stack 100 </ b> B in which a plurality of DR laminates 100 are laminated in the thickness direction of the DR laminate 100. A cross-sectional view conceptually showing the DR laminate 100 in the form of such a stack 100B is shown in FIG.

(4) Second Sheet The second sheet 2 of the laser dicing sheet 10 included in the DR laminate 100 according to the present embodiment is one surface of the first sheet 1, specifically, the first sheet 1. It is laminated | stacked on the surface (back surface) on the opposite side to the side which opposes the adhesive layer 3 of this.
The second sheet 2 has an annular shape in plan view. When the planar view shape of the second sheet 2 is annular, the thick portion of the laser dicing sheet 10 is less likely to be unevenly distributed in the planar view. As a result, it is easy to avoid a situation in which tilting occurs when the DR laminate 100 is stacked due to uneven distribution of thick portions, or traces of uneven thick portions remain in the DR stack 100. It becomes. Here, the term “annular” refers to a shape that is not completely annular but partially discontinuous (for example, a C-shape) in a plan view (the viewpoint direction is a direction parallel to the normal of the main surface). Shape). The rear surface of the first sheet 1 is exposed in an annular inner region in plan view, that is, in a region surrounded by the second sheet 2 in plan view and in which the second sheet 2 does not exist. In this specification, this region on the back surface of the first sheet 1 is also referred to as an “in-ring exposed region”. The in-ring exposed region includes a region (laser irradiation region) irradiated with a laser when the laser dicing sheet 10 is used.

  The method for fixing the second sheet 2 to the first sheet 1 is not particularly limited. As shown in FIG. 1, the second sheet 2 has a structure including a base film 21 and an adhesive layer 22, and the second sheet 2 and the first sheet 1 are fixed by the adhesive layer 21. May be. Alternatively, these sheets may be fixed so as to directly contact each other by a method such as heat fusion.

  Since the second sheet 2 has an annular shape in plan view, as described above, even when the DR laminated body 100 is in the form of the wound body 100A or the stacked body 100B, the wound body 100A. When the DR laminated body 100 (a part of the DR laminated body 100 in the case of the winding body 100A, one DR laminated body 100 in the case of the stack body 100B) is taken out from the stack body 100B, It is difficult for the laser dicing sheet 10 in the DR laminate 100 to peel off from the release sheet 11 (DR laminate supply failure).

This point will be described in detail using a specific example in which the DR laminate 100 is in the form of a wound body 100A.
FIG. 4 conceptually shows a state immediately before the DR laminate 100 is unwound from the winding body 100A and one of the laser dicing sheets 10 attached to the long release sheet 11 is made peelable. It is a fragmentary sectional view shown. Note that the wound body 100A shown in FIG. 4 has a DR laminate 100 in the form of a long body, and laser dicing is performed on the side closer to the rotation center of the winding core C of the wound body 100A (inner circumferential side). Winding is performed such that the sheet 10 is disposed and the release sheet 11 is disposed on the side (outer peripheral side) that is distal to the rotation center of the core C of the winding body 100A.

  In the DR laminated body 100 according to the present embodiment, when the DR laminated body 100 is fed from the winding body 100A, the pressure-sensitive adhesive layer 3 is formed on the outermost release sheet 11a and the release surface of the outermost release sheet 11a. The laser dicing sheet 10 to which the side surface is affixed, and the release sheet 11b that is one inner circumference side than the outermost release sheet 11a (the opposite side of the release surface (the release sheet back surface) are the laser dicing sheet 10 Of the second sheet 2 side (the back surface of the base material))), and peeling occurs at the interface between the laser dicing sheet 10 and the release sheet 11b. The laser dicing sheet 10 can be brought into a peelable state.

  As will be described below, this is also referred to as a surface of the second sheet 2 of the laser dicing sheet 10 opposite to the side facing the first sheet 1 (hereinafter referred to as “back surface of the second sheet 2”). This is because the adhesion of the release sheet 11b to the back surface of the release sheet is appropriately controlled. Specifically, the stack obtained by placing the surface opposite to the release surface of the release sheet 11b on one surface of the second sheet 2 is in an environment of 40 ° C. and a relative humidity of 80%. Then, a load of 19.6 N was applied for 1 hour from the release surface side of the release sheet 11b, and then left to stand for 1 hour in an environment of 23 ° C. and a relative humidity of 50% with no load. The peel force measured when the stack release sheet 11b is peeled 180 ° is 50 mN / 50 mm or less.

  Details of the test for measuring the peeling force will be described. Note that the second sheet 2 and the release sheet 11b of the laser dicing sheet 10 are not substantially different in peeling force even when a test sheet made of the same material is used instead. The test method will be described. First, a test second sheet made of the same material as the second sheet 2 and a test release sheet made of the same material as the release sheet 11 are prepared. Next, as shown in FIG. 5A, a second test sheet corresponding to the surface of the second sheet 2 opposite to the side facing the first sheet 1 (the back surface of the second sheet 2). The second test sheet 51 is fixed so that one surface of the sheet 51, specifically, the surface 51a made of the base film 511 is exposed. In FIG. 5A, the second test sheet 51 is fixed to the SUS flat plate 50 by the adhesive layer 512 of the second test sheet 51. Subsequently, a surface 52 a opposite to the release surface of the test release sheet 52 is placed on one surface 51 a of the second test sheet 51 to obtain the stack 53.

  For this stack 53, as shown in FIG. 5 (b), a load of 19.6 N was applied from the release surface side of the test release sheet 52 in an environment of 40 ° C. and a relative humidity of 80%. Let sit for 1 hour. Thereafter, the load is removed, and the sample is further left to stand for 1 hour under no load in an environment of 23 ° C. and a relative humidity of 50%. Then, the peeling force is measured while peeling off the test release sheet 52 of the stacked body 53 after standing still by 180 °, and the adhesion is evaluated by the measured peeling force. Hereinafter, this peeling force is also referred to as “peeling force A”.

  Test corresponding to the second sheet 51 for testing corresponding to the second sheet 2 of the laser dicing sheet 10 included in the DR laminate 100 according to the present embodiment and the release sheet 11 included in the DR laminate 100 according to the present embodiment. When the release sheet 52 is used, the peeling force A is 50 mN / 50 mm or less. When the peeling force A is 50 mN / 50 mm or less, peeling may occur at the interface between the laser dicing sheet 10 and the inner circumferential peeling sheet 11b when the DR laminate 100 is unwound from the winding body 100A. Realized stably.

  When the peeling force A exceeds 50 mN / 50 mm, the peeling at the interface between the laser dicing sheet 10 and the outer circumferential release sheet 11 a is greater than the peeling at the interface between the laser dicing sheet 10 and the inner circumferential peeling sheet 11 b. The possibility of delamination increases. When such peeling occurs, the DR laminated body 100 is not properly fed out, and the laser dicing sheet 10 remains on the outer peripheral surface (back surface of the release sheet) of the inner peripheral release sheet 11b. When this DR laminate supply failure occurs, the long DR laminate 100 is present in a state where the laser dicing sheet 10 exposes the pressure-sensitive adhesive layer 3 on the surface on the release sheet 11 side, There is an increased risk of serious problems such as adhesion of the pressure-sensitive adhesive layer 3 to parts in equipment for feeding such as a roller (for example, a pinch roller) that passes when the release sheet 11 is wound.

  From the viewpoint of more stably reducing the possibility of such a DR laminate supply failure, the peeling force A is preferably 45 mN / 50 mm or less, and more preferably 40 mN / 50 mm or less. The lower limit of the peeling force A is not set from the viewpoint of reducing the possibility of a DR laminate supply failure.

The method for making said peeling force A 50 mN / 50 mm or less is not specifically limited. Specific examples are as follows.
(First example)
As a first example, controlling the surface roughness of the surface of the second sheet 2 opposite to the side facing the first sheet 1 (the back surface of the second sheet 2) can be mentioned. By increasing the surface roughness of the back surface of the second sheet 2, that is, by making it a rough surface, the true contact area between the back surface of the second sheet 2 and the back surface of the release sheet 11 can be reduced. At this time, the peeling force A decreases.

  How much the surface roughness of the back surface of the second sheet 2 is set to control the peeling force A to 50 mN / 50 mm or less depends on the material of the base film constituting the back surface of the second sheet 2 Since it varies depending on the material of the support film of the release sheet 11 constituting the release sheet back surface, the surface roughness of the release sheet back surface, the pressure applied between the DR laminates 100 that overlap in the storage state, etc., it cannot be defined definitely. . However, if the arithmetic average roughness Ra of the back surface of the second sheet 2 is 0.3 μm or more, it is more stably realized that the peeling force A is 50 mN / 50 mm or less. In particular, even when the base film constituting the back surface of the second sheet 2 is made of a material having relatively poor rigidity such as polyolefin, the arithmetic average roughness Ra of the back surface is 0.3 μm or more. By using the second sheet 2, it is more stably realized that the peeling force A is controlled to 50 mN / 50 mm or less. The adjustment of the arithmetic average roughness Ra of the back surface of the second sheet 2 can be performed by the same method as the adjustment of the arithmetic average roughness Ra of the back surface of the first sheet 1, and a rough surface such as a sandblast treatment It may be adjusted by the conversion process.

  As seen from the arithmetic surface roughness Ra on the back surface of the first sheet, it is difficult to use a material having a large arithmetic surface roughness Ra as a material constituting the laser irradiation region of the laser dicing sheet. It is also possible to adjust the arithmetic surface roughness Ra of the surface irradiated with the laser at the time of use so as not to be too small and not too small so as to achieve both laser transparency and prevention of DR laminate supply failure. However, in the end, both performances can be inadequate. However, the laser dicing sheet 10 according to the present embodiment includes the second sheet 2, so that the arithmetic surface of the surface irradiated with the laser when used as a material constituting the laser irradiation region as in this example. Without using a material having a large roughness Ra, it is possible to provide a surface having a large arithmetic surface roughness Ra on the same side as the surface including the laser irradiation region in the laser dicing sheet 10, and as a result, a DR laminate It is realized that supply failure is less likely to occur.

(Second example)
As a second example, the material constituting the surface of the second sheet 2 opposite to the side facing the first sheet 1 (the back surface of the second sheet 2), specifically, shown in FIG. In the 2nd sheet | seat 2, selecting the kind of material which comprises the base film 21 is mentioned. As a general trend, the material is preferably a rigid material. Examples of materials having such characteristics that are easily available from the market and inexpensive are polyester materials such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN). Among these, polyethylene terephthalate (PET) is preferable because of its excellent balance of properties, availability, and cost.

  Generally, a resin material can have a rigid characteristic by including the structural unit derived from an aromatic compound in the polymer contained in this. However, such an aromatic compound-containing resin material has a high laser absorptivity, particularly a laser absorptivity at 1064 nm. For this reason, it is difficult to use an aromatic compound-containing resin-based material as a material constituting the laser irradiation region of the laser dicing sheet. However, the laser dicing sheet 10 according to the present embodiment is provided with the second sheet 2, so that, as in this example, the laser dicing sheet 10 can be used without using an aromatic compound-containing resin-based material as a material constituting the laser irradiation region. Realizing that the surface of the dicing sheet 10 on the same side as the surface including the laser irradiation region is provided with a material surface made of an aromatic compound-containing resin-based material, and as a result, it is difficult to cause a defective supply of the DR laminate. doing.

  In both the first example and the second example, by appropriately selecting the material constituting the release sheet 11, it is possible to more stably realize the control of the peeling force A to 50 mN / 50 mm or less.

  The thickness of the second sheet 2 is not particularly limited, but if it is excessively thin, there is a concern that the second sheet 2 may break in the expanding process, and if it is excessively thick, the ring frame may be pulled down in the expanding process. There is concern that it will not be performed properly. Therefore, the thickness of the second sheet 2 is preferably 10 μm or more and 100 μm or less, more preferably 15 μm or more and 60 μm or less, and particularly preferably 20 μm or more and 40 μm or less.

  The positional relationship between the outer peripheral side edge in the plan view of the second sheet 2 and the outer peripheral side edge in the plan view of the first sheet 1 is not particularly limited. The outer surface of the first sheet 1 and the outer surface of the second sheet 2 may be substantially continuous to form one surface, or the second sheet 2 may be more than the outer surface of the first sheet 1. The outer surface of the second sheet may protrude outward in the main surface direction of the second sheet, or vice versa. However, the outer side surface of the first sheet 1 protrudes excessively in plan view rather than the outer side surface of the second sheet 2, and as a result, the DR laminated body 100 is in the storage state before use in the first sheet 1 When the surface (back surface) opposite to the side facing the pressure-sensitive adhesive layer 3 in the protruding portion of the sheet is in contact with the back surface of the release sheet 11 of the other DR laminate 100, the first sheet is formed in this portion. There is a concern that the back surface of 1 and the release sheet back surface of the release sheet 11 are in close contact with each other, causing a defective supply of the DR laminate. Therefore, when the outer surface of the first sheet 1 protrudes in a plan view rather than the outer surface of the second sheet 2, such a problem should not occur. Specifically, the protrusion width in this case is preferably within a few mm.

2. Laser Dicing Sheet A laser dicing sheet 10 according to an embodiment of the present invention is obtained by peeling the release sheet 11 from the DR laminate 100 according to the present embodiment.
The first sheet 1 of the laser dicing sheet 10 according to the present embodiment is such that the second sheet 2 is annular in plan view, so that the surface on the side where the second sheet 2 is laminated is the second sheet 2. It has a ring-exposed region that is a region surrounded by the sheet 2 and where the second sheet is not laminated. And the area | region which overlaps with the ring exposure area | region of the 1st sheet | seat 1 in the surface of the adhesive layer 3 in planar view contains the area | region where plate-shaped members, such as a semiconductor wafer, are stuck.

  When the region where the plate member is affixed has a portion located outside the exposed region in the ring in plan view, depending on the material constituting the second sheet 2 (specifically, the base film 21 is PET). And a problem that a laser beam is not irradiated on the plate-shaped member may occur. Therefore, it is preferable that the region where the plate-like member is affixed is located entirely within the ring-exposed region in plan view. From the viewpoint of realizing such a relationship more stably, the diameter of the inscribed circle in the plan view of the in-ring exposed region is larger than the diameter of the circumscribed circle in the plan view of the region to which the plate member is attached. Is preferably 2 mm or more.

3. Manufacturing method of DR laminated body The manufacturing method of DR laminated body 100 which concerns on this embodiment is not specifically limited. What is necessary is just to manufacture combining a well-known coating method, the sticking method, the cutting method (a half cut is included), the peeling method, etc. suitably. Below, an example of the manufacturing method in case the 2nd sheet | seat 2 has a structure as shown in FIG. 1 is shown.

  The pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 3 is applied on the release surface of the release sheet 11, and the obtained coating film is dried to obtain the pressure-sensitive adhesive layer 3. The coating method is arbitrary, and examples include a die coater, a curtain coater, a spray coater, a slit coater, and a knife coater. The drying method is also arbitrary. For example, it may be performed by heating at about 80 to 120 ° C. for several minutes, or may be air drying that is left in the atmosphere. A resin film that gives the first sheet 1 is pasted on the surface of the pressure-sensitive adhesive layer 3 thus obtained opposite to the side facing the release sheet 11, and the release sheet 11, the pressure-sensitive adhesive layer 3, and the first The 1st laminated body by which the resin-type film which gives the sheet | seat 1 was laminated | stacked in this order is obtained. On the other hand, an adhesive composition for preparing a resin film (hereinafter also referred to as “base film”) and a process film for providing the base film 21 of the second sheet 2 and forming the adhesive layer 22 on the process film. Apply the object. In addition, this application | coating method is not specifically limited like the case where said adhesive composition is apply | coated. The obtained coating film is dried (this drying method is not particularly limited as in the case of drying the coating film of the pressure-sensitive adhesive composition). Next, the adhesive layer 22 formed on the process film is bonded to the surface on the side facing the first sheet 1 when it becomes a part of the second sheet 2 in the base film, and the base film is used. An adhesive sheet on which the film, the coating film for providing the adhesive layer 22 and the process film are laminated is obtained. From the surface of the adhesive sheet on the base film side, the coating film that gives the base film and the adhesive layer 22 is cut into half the same shape as the in-ring exposed region to be formed on the first sheet, and the ring is cut. A portion having the same shape as the inner exposed region is removed. And a process film is removed from an adhesive sheet, the surface by the side of the resin film which gives the 1st sheet | seat 1 of a 1st laminated body, and the surface by the side of the adhesive bond layer 22 of an adhesive sheet are bonded, DR The raw material of the laminated body 100 is obtained.

  Next, the base film, the adhesive layer 22 and the resin film that gives the first sheet 1 are cut by half-cut from the surface of the DR laminate 100 on the base film side, and unnecessary portions are removed. Then, the external shape of the laser dicing sheet 10 is cut out. Thus, the DR laminate 100 in which the laser dicing sheet 10 is laminated on the release sheet 11 is obtained. In addition, you may further perform processes, such as a heating and curing, so that the adhesive bond layer 22 and the adhesive layer 3 may have appropriate adhesiveness as needed.

4). Hereinafter, an example of a method for manufacturing a chip body using the laser dicing sheet 10 obtained by peeling the release sheet 11 from the DR laminate 100 according to the present embodiment will be described.

  First, a plate-like member is affixed to a predetermined region on the surface opposite to the side facing the first sheet 1 in the pressure-sensitive adhesive layer 3 of the laser dicing sheet 10. As described above, the predetermined region is a portion that overlaps with the in-ring exposed region in plan view. Examples of the plate-like member include a semiconductor wafer, a glass substrate, a ceramic substrate, an organic material substrate such as an FPC, and a member made of a metal material such as a precision component. Further, when the plate-shaped member is a semiconductor wafer or the like and the circuit is already formed, the surface on which the circuit is formed may be attached so as to face the adhesive layer 3, or the circuit is formed. It may be affixed so that the back surface which is not facing the adhesive layer 3. In addition, what is necessary is just to stick a ring frame to the adhesive layer 3 of the laser dicing sheet 10 according to sticking of this plate-shaped member, when using a ring frame. FIG. 6 is a cross-sectional view conceptually showing the state in which the plate-like member 61 and the ring frame 62 are attached to the pressure-sensitive adhesive layer 3 of the laser dicing sheet 10 in this way.

  Next, the laser is irradiated so that the first sheet 1 and the pressure-sensitive adhesive layer 3 are transmitted through the first sheet 1 and the pressure-sensitive adhesive layer 3 to the plate-like member 61 with the exposed region in the ring of the first sheet 1 of the laser dicing sheet 10 as the incident surface. . At this time, it is preferable to irradiate the laser beam so that the laser beam is condensed inside the plate-like member 61 because damage to the first sheet 1 and the pressure-sensitive adhesive layer 3 is small. The laser light source is a device that generates light having a uniform wavelength and phase, and the types of laser light include Nd-YAG laser, Nd-YVO laser, Nd-YLF laser, and titanium sapphire laser that generate pulsed laser light. The thing which causes multiphoton absorption can be mentioned. The wavelength of the laser light is preferably 800 to 1100 nm, and more preferably 1064 nm.

  The modified portion is formed inside the plate-like member 61 along the planned cutting line by the laser light applied to the inside of the plate-like member 61 to form a dicing line. The number of times the laser beam scans one scheduled cutting line may be one time or multiple times. Preferably, the irradiation position of the laser beam and the position of the planned cutting line between the circuits are monitored, and the laser beam is irradiated while aligning the laser beam. You may irradiate a laser beam separately for the alignment at this time.

  When the laser irradiation is thus completed, the laser dicing sheet 10 to which the plate member after laser irradiation is attached is extended outward in the main surface direction of the sheet using an expanding device or the like. A tensile force is applied to the plate member in accordance with the extension of the laser dicing sheet 10, and the modified portion in the plate member is brittlely broken by this tensile force. As a result, the plate-like member 61 is cut along the dicing line into individual pieces, and a chip body is obtained as each of the divided pieces.

  The method for extending the laser dicing sheet 10 may be appropriately set according to the type of the plate-like member 61 to be singulated, the structure / composition of the modified portion formed in the plate-like member 61, etc. In many cases, the film is stretched by about 5 to 50 mm at a speed of 5 to 600 mm / min. The obtained chip body 71 on the laser dicing sheet 10 may be individually taken out by performing a pick-up process, or a cleaning process for removing crushed powder or the like may be performed before that.

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further more concretely, the scope of the present invention is not limited to these Examples etc.

[Example 1]
(1) Preparation of coating composition for forming pressure-sensitive adhesive layer Acrylic copolymer (2-ethylhexyl acrylate / vinyl acetate / acrylic acid / methyl methacrylate / 2-hydroxyethyl methacrylate = 23.5 / 70 / Polypropylene glycol (Mw = 700) as an energy ray polymerizable compound with respect to 100 parts by weight of 1/5 / 0.5 (mass ratio), Mw = 600,000, Mw / Mn = 6.0, Tg = 3 ° C. , 80 parts by weight of a bifunctional urethane acrylate oligomer (Mw = 4000) composed of a copolymer of isophorone diisocyanate and 2-hydroxypropyl acrylate, 3 parts by weight of a photopolymerization initiator (“Irgacure 184” manufactured by BASF) and an isocyanate-based crosslinking agent (Nippon Polyurethane “Coronate L”) 2 parts by weight (all solid And a coating composition for forming an adhesive layer.

(2) Preparation of Resin Film for Giving First Sheet A long polyvinyl chloride film having the following characteristics and a thickness of 80 μm was prepared as a resin film for giving the first sheet.
Arithmetic average roughness Ra of surface: 0.03 μm
Linear transmittance at a wavelength of 1064 nm: 92%
Phase difference at a wavelength of 1064 nm: 32 nm
Young's modulus: 280 MPa

(3) Production of first laminate Adhesive prepared as described above on the release surface of a long release sheet ("SP-PET3811" manufactured by Lintec) having a thickness of 38 µm and a polyethylene terephthalate film as a support film The coating composition for forming the agent layer was applied so that the thickness after drying was 5 μm. The obtained coating film was dried at 100 ° C. for 1 minute to obtain a laminate of a release sheet and an adhesive layer. Affixing one surface of the resin-based film that gives the first sheet (the surface opposite to the surface having the arithmetic average roughness Ra) on the surface of the laminate on the pressure-sensitive adhesive layer side, 1 laminate was obtained.

(4) Preparation of adhesive sheet 100 parts by mass of an acrylic copolymer (butyl acrylate / acrylic acid = 90/10 (mass ratio), Mw = 800,000) and an isocyanate-based crosslinking agent (“Coronate L” manufactured by Nippon Polyurethane Co., Ltd.) ) (All blending ratios in terms of solid content) to form a coating composition for forming an adhesive layer.
A long polyethylene terephthalate film (surface arithmetic average roughness Ra: 0.02 μm) having a thickness of 38 μm was prepared as a resin-based film (base film) for providing the base film of the second sheet. Moreover, a polyethylene terephthalate film ("SP-PET 381031" manufactured by Lintec Co., Ltd.) subjected to release treatment is prepared as a process film, and a coating composition for forming the above adhesive layer on the release surface of the process film is prepared. The dried coating was dried at 100 ° C. for 1 minute to form an adhesive layer. One surface of the base film (the surface opposite to the surface having the arithmetic average roughness of the above surface) is formed on the surface on the adhesive layer side of the laminate comprising the process film and the adhesive layer thus obtained. Affixed to obtain an adhesive sheet. Next, a half cut is performed on the adhesive sheet from the surface on the base film side to cut the base film and the coating film (this half cut is also referred to as “first half cut”), and the diameter is viewed in plan view. 100 cutting lines (closed curves) having a circular shape of 210 mm were produced in the longitudinal direction of the original fabric. A line connecting the centers of 100 circles formed by these cutting lines was made parallel to the longitudinal direction of the original fabric, and the distance between the centers of the two circles arranged at the closest positions was 278 mm. The base film and the coating film inside these cutting lines were removed to obtain an adhesive sheet in which the process film was exposed in the portion corresponding to the exposed area in the ring.

(5) Production of DR laminate The above-mentioned first laminate is obtained by removing the process film from the adhesive sheet on which the process film is exposed at the portion corresponding to the exposed region in the ring, and exposing the surface on the adhesive layer side. The surface on the resin-based film side that gives the first sheet and the surface on the adhesive layer side of the adhesive sheet from which the first half-cut and unnecessary portions have been removed are bonded, and the DR laminate I got the original fabric.
Next, a first laminate other than the base film, the adhesive layer, and the release sheet (that is, a resin system that provides the first sheet) from the base film side surface with respect to the raw material of the DR laminate The film and pressure-sensitive adhesive layer) were cut into half, and 100 cutting lines (closed curves) forming a circle having a diameter of 270 mm in plan view were produced. The centers of the circles formed by these cutting lines were made to coincide with the centers of the circles having a diameter of 210 mm in plan view previously formed by the first half cut. Then, the first laminate other than the base film and the adhesive layer and the release sheet, which were outside the cutting line forming a circle having a diameter of 270 mm in plan view, were removed.

In this way, a DR laminate was obtained in which 100 pieces of laser dicing sheets having the following shape and arrangement were arranged side by side in the longitudinal direction on the release surface of the long release sheet.
Planar shape of the exposed portion in the ring: a circle having a diameter of 210 mm Planar shape of the second sheet: an annular shape having an inner diameter of 210 mm and a width of 30 mm Laser planing shape of the laser dicing sheet: a circle having a diameter of 270 mm Of laser dicing sheets in the longitudinal direction: 8mm
This DR laminate was wound in the longitudinal direction to form a wound body.

[Example 2]
The resin-based film that gives the base film of the second sheet in Example 1 was changed to polybutylene terephthalate (surface arithmetic average roughness Ra: 0.02 μm) with a thickness of 25 μm, and a plan view of the exposed portion in the ring The manufacturing method of Example 1 except that the first half-cutting method was changed so that the shape of the second sheet was a circle with a diameter of 205 mm and the second sheet had a circular shape with an inner diameter of 205 mm and a width of 37.5 mm. A similar manufacturing method was carried out to produce a wound body of the DR laminate.

Example 3
While changing the resin film which gives the base film of the 2nd sheet | seat in Example 1 to the low density polyethylene (surface arithmetic average roughness Ra: 0.7 micrometer) of thickness 25 micrometers, planar view of the exposed part in a ring Except for changing the first half-cut method so that the shape of the second sheet is a circle with a diameter of 202 mm and the second sheet has a circular shape with an inner diameter of 202 mm and a width of 39 mm, it is the same as the manufacturing method of Example 1. The manufacturing method was implemented and the wound body of DR laminated body was produced.

Example 4
The manufacturing method of Example 1 is the same as that of Example 1 except that the resin film that gives the base film of the second sheet in Example 1 is changed to polypropylene having a thickness of 25 μm (arithmetic surface roughness Ra: 0.5 μm). The manufacturing method of (1) was implemented, and the wound body of DR laminated body was produced.

Example 5
In order to produce a resin film that gives the first sheet in Example 1, first, a urethane acrylate oligomer as one of the materials was synthesized. Polypropylene glycol (PPG, Mw = 400), isophorone diisocyanate (IPDI), and hydroxyethyl methacrylate (HEMA) were prepared at a weight ratio of 4: 5: 2, and PPG and IPDI were reacted in the presence of a catalyst. HEMA was bonded to the residual isocyanate group of the obtained urethane oligomer to obtain a urethane acrylate oligomer having Mw = 8000. Using this, a resin composition having the following composition was obtained.
100 parts by mass of urethane acrylate oligomer,
110 parts by mass of a monofunctional monomer (isobornyl acrylate), and 2.2 parts by weight of a photopolymerization initiator (“Irgacure 184” manufactured by BASF)

A polyethylene terephthalate film is used as a support film, and the above prepared resin composition has a thickness of 100 μm on the release surface of a long release sheet (“SP-PET3811” manufactured by Lintec Corporation) having a thickness of 38 μm. Applied. The obtained coating film was irradiated with ultraviolet rays (1500 mJ / cm ² ) and polymerized to obtain a laminate comprising a release sheet and a polyurethane acrylate film laminated on the release surface. Prepare another release sheet that is the same as the above release sheet, and attach the release surface of the release sheet to the surface of the laminate on the polyurethane acrylate film side, and then laminate the release sheet, polyurethane acrylate film, and release sheet Got the body. Hereinafter, this laminate is also referred to as an intermediate laminate.

  While releasing one release sheet in this intermediate laminate, the surface of the exposed polyurethane acrylate film was applied to the adhesive layer side surface of the laminate of the release sheet prepared in Example 1 and the adhesive layer. did. The release sheet affixed to the resin film made of the polyurethane acrylate film in the laminate thus obtained was peeled off to obtain a first laminate.

Hereinafter, the first half-cut method is changed except that the exposed portion in the ring has a circular shape with a diameter of 205 mm and the second sheet has a circular shape with an inner diameter of 205 mm and a width of 37.5 mm. Implemented the manufacturing method similar to the manufacturing method of Example 1, and obtained the wound body of DR laminated body.
In addition, the characteristics of the polyurethane acrylate film having a thickness of 100 μm obtained by separately preparing the intermediate laminate and peeling off both release sheets in the laminate were as follows.
Arithmetic mean surface roughness Ra: 0.09 μm
Linear transmittance at a wavelength of 1064 nm: 92.5%
Phase difference at a wavelength of 1064 nm: 0.8 nm
Young's modulus: 380 MPa

[Comparative Example 1]
Except for changing the resin-based film that gives the first sheet in Example 1 to a low-density polyethylene film having a thickness of 80 μm and having the following characteristics, a manufacturing method similar to the manufacturing method of Example 1 was carried out, A wound body of the DR laminate was produced.
Arithmetic mean surface roughness Ra: 0.5 μm
Linear transmittance at a wavelength of 1064 nm: 87%
Phase difference at a wavelength of 1064 nm: 425 nm
Young's modulus: 100 MPa

[Comparative Example 2]
The resin-based film that gives the base film of the second sheet in Example 1 was changed to a polyvinyl chloride film having a thickness of 25 μm (the surface arithmetic average roughness Ra: 0.05 μm). A manufacturing method similar to the manufacturing method was performed to produce a wound body of the DR laminate.

[Comparative Example 3]
Except for changing the resin-based film that gives the first sheet in Example 1 to a polyvinyl chloride film having a thickness of 80 μm and having the following characteristics, a manufacturing method similar to the manufacturing method of Example 1 was carried out, A wound body of the DR laminate was produced.
Arithmetic average roughness Ra of surface: 0.6 μm
Linear transmittance at a wavelength of 1064 nm: 35.2%
Phase difference at a wavelength of 1064 nm: 48 nm
Young's modulus: 260 MPa

[Comparative Example 4]
In Example 1, the resin-based film and the pressure-sensitive adhesive layer that give the first sheet from the resin-based film side that gives the first sheet to the first laminate without producing the second laminate. A half cut for cutting was performed, and a cutting line forming a circle having a diameter of 270 mm in plan view was produced. The first laminated body outside the cutting line was removed.
Thus, the laser dicing sheet having a circular shape of 270 mm in plan view and not having the second sheet was laminated on the release surface of the release sheet so that the pressure-sensitive adhesive layer forms a contact surface with the release sheet. A wound body of the DR laminate was obtained.

[Test Example 1] Measurement of Young's modulus For the resin-based film that gives the first sheet used in Examples and Comparative Examples, JIS K7161 was used using a universal tensile testing machine (Tensilon RTA-T-2M manufactured by Orientec Co., Ltd.). : Based on 1994, Young's modulus was measured under conditions of a tensile speed of 200 mm / min in an environment of 23 ° C. and a relative humidity of 50%. The result is as described above.

[Test Example 2] Measurement of linear transmittance For the resin-based film that gives the first sheet used in the examples and comparative examples, an ultraviolet / visible / near-infrared spectrophotometer (“UV-3101PC” manufactured by Shimadzu Corporation) was used. Used, the linear transmittance in the wavelength range of 200 to 1200 nm was measured, and the value of 1064 nm was read. The result is as described above.

[Test Example 3] Retardation measurement Retardation film inspection apparatus ("RETS-100" manufactured by Otsuka Electronics Co., Ltd. (detector "MCPD-7700") was used for the resin-based film giving the first sheet used in the examples and comparative examples. ))), The phase difference was measured in the range of 800 to 1100 nm, and the value of the phase difference at a wavelength of 1064 nm was read. The result is as described above.

[Test Example 4] Measurement of Arithmetic Average Roughness Ra Surface used as the first sheet in the resin-based film that gives the first sheet used in the examples and comparative examples, and the surface serving as the back surface of the first sheet, and A contact-type surface roughness meter ("SURFTEST SV-3000 manufactured by Mitsutoyo Co., Ltd.) is used for the surface that becomes the back surface of the second sheet when it is a part of the second sheet in the resin film that provides the base film of the second sheet. )), The arithmetic average roughness Ra was measured in 10 planes in accordance with JIS B0601-2001, and the average value was calculated. The measurement conditions were as follows.
(When Ra ≦ 1.0)
Cut-off value λc: 0.25 mm, evaluation length Ln: 1.25 mm
(When Ra> 1.0)
Cut-off value λc: 0.8 mm, evaluation length Ln: 4 mm
The measurement results are as described above, and are also shown in Table 1.

[Test Example 5] Measurement of peel force Separately prepared second laminates prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were cut into a size of 50 mm x 150 mm to obtain a test laminate. For the DR laminate in Comparative Example 4, the adhesive of the second sheet on the surface facing the pressure-sensitive adhesive layer in the resin-based film that gives the first sheet when it becomes the first sheet. An adhesive layer having the same composition as the layer was laminated, and the obtained laminate was also one of the test laminates, which was used as a reference value. The surface on the adhesive layer side of each of these test laminates is attached to one surface of a SUS flat plate to obtain a laminate in which the resin film, the adhesive layer, and the SUS flat plate are laminated in this order. It was.

This laminate is placed on a test bench, and the release surface of a test release sheet ("SP-PET3811" manufactured by Lintec) made of the same material as the release sheet of the DR laminate is placed on the surface of the resin film. The opposite surface (release sheet back surface) was overlapped, and a 2 kg weight was placed on the release surface side of the release sheet in the resulting stack. This state was maintained for 1 hour in an environment of 40 ° C. and a relative humidity of 80%. Further, the weight was removed, and the mixture was allowed to stand for 1 hour under no load in an environment of 23 ° C. and 50% relative humidity.
The test release sheet for the stack after standing was 300 mm / mm at an angle of 180 ° with a universal tensile tester (Tensilon RTA-T-2M manufactured by Orientec Co., Ltd.) in an environment of 23 ° C. and 50% relative humidity. The film was peeled off at a rate of minutes to obtain a peeling force. The measurement results are shown in Table 1.

[Test Example 6] Evaluation of DR laminated body supply property The DR laminated body wound body according to each of Examples and Comparative Examples was set in a wafer bonding apparatus ("RAD-2500m / 12" manufactured by Lintec Corporation). Using the apparatus, the laser dicing sheet was peeled from the release sheet in the DR laminate, and a silicon wafer having a diameter of 200 mm and a thickness of 100 μm and an 8-inch wafer ring frame were attached to each of the peeled laser dicing sheets.
As a result, if the number of laser dicing sheets that were properly peeled off from the release sheet and were not bonded to the silicon wafer was 4 or less, it was determined as “good”, and the laser dicing that resulted in inappropriate bonding The case where there were 5 or more sheets was defined as “bad”. The evaluation results are shown in Table 2.

[Test Example 7] Evaluation of expandability and dicing property The release sheet was peeled from the DR laminates in the examples and comparative examples, and the obtained laser dicing sheet was subjected to the same method as in Test Example 6 and the same silicon wafer as in Test Example 6 And affixed to the ring frame. The silicon wafers affixed to the laser dicing sheets according to Examples 1 to 4 and Comparative Examples 1 to 3 were entirely located in the in-ring exposed region of the first sheet in plan view.

  Using a laser irradiation device (“DFL7360” manufactured by DISCO, wavelength: 1064 nm), a laser that focuses light inside the wafer through the laser dicing sheet from the side facing the adhesive layer of the silicon wafer is 2 mm × Irradiation was performed while scanning along a planned cutting line set to form a 2 mm chip body. After irradiating all the planned cutting lines with laser, using an expander (“DDS2010” manufactured by DISCO), the laser dicing sheet is pulled down at a speed of 300 mm / min, and the silicon wafer on the adhesive layer side surface of the laser dicing sheet The region to which is attached was extended 15 mm in the main surface inward and outward directions.

  As a result, when the laser dicing sheet is stretched without problems, it is determined that the expandability is “good”, and the chip body is formed by dividing the wafer along all the planned cutting lines of the silicon wafer. When the ratio of the number of chips actually divided into individual chips (chip yield) to the number of chips obtained was 90% or more, the dicing property was determined to be “good”. On the other hand, when the laser dicing sheet fell off from the ring frame or the laser dicing sheet was torn, it was determined that the expandability was “impossible”. Further, when the yield of chips in the division of the silicon wafer was less than 90%, the dicing property was determined as “impossible”. The evaluation results are shown in Table 2.

  As is clear from Tables 1 and 2, the DR laminated body of the example satisfying the conditions of the present invention was excellent in pre-cut property, and the DR laminated body supply failure was difficult to occur. Moreover, it was excellent in dicing properties and expanding properties.

  The laser dicing sheet-release sheet laminate according to the present invention is suitable as a laminate of a laser dicing sheet and a release sheet used in a dicing process including an operation of irradiating a laser so as to transmit the dicing sheet, such as stealth dicing. Used for.

DESCRIPTION OF SYMBOLS 100 ... DR laminated body 10 ... Laser dicing sheet 1 ... 1st sheet 2 ... 2nd sheet 21 ... Base film 22 ... Adhesive layer 3 ... Adhesive layer 11 ... Release sheet 100A ... Winding body 11a ... Outermost circumference Peeling sheet 11b ... Peeling sheet further on the inner circumference side than the outermost peeling sheet C ... Core material 100B ... Stack body 50 ... SUS flat plate 51 ... Second sheet for testing 511 ... Base film for second sheet for testing 512 ... Adhesive layer of second test sheet 51a ... One surface 52 of second test sheet 52 ... Release sheet for test 52a ... Surface opposite to the release surface of the test release sheet 53 ... Stack 61 ... Plate-like member 62 ... Ring frame

Claims (9)

A laser dicing sheet comprising a first sheet, a second sheet laminated on one side of the first sheet, and an adhesive layer laminated on the other side of the first sheet; and the laser A laser dicing sheet-release sheet laminate comprising a release sheet laminated so that the release surface faces the surface on the pressure-sensitive adhesive layer side of the dicing sheet,
The first sheet has a Young's modulus at 23 ° C. of 30 MPa or more and 600 MPa or less, and the arithmetic average roughness Ra of one surface of the first sheet is less than 0.1 μm,
The second sheet has an annular shape in plan view, and the in-ring exposed region in which the second sheet is not stacked is surrounded by the second sheet in plan view on one surface of the first sheet. , Including a region irradiated with laser when using the laser dicing sheet,
The release surface of the release sheet has a region where the laser dicing sheet is not laminated,
For the stack obtained by placing a surface opposite to the release surface of the release sheet on one surface of the second sheet, the test release in an environment of 40 ° C. and a relative humidity of 80%. Apply 19.6N load from the peel side of the sheet for 1 hour,
Further, peeling is measured when the test release sheet of the stack after standing is left for 1 hour under no load in an environment of 23 ° C. and relative humidity of 50%, and then peeled off by 180 °. A laser dicing sheet-release sheet laminate, wherein the force is 50 mN / 50 mm or less.   The first sheet has a linear transmittance of 80% or more at the wavelength of 1064 nm and a phase difference of 100 nm or less at a wavelength of 1064 nm for at least a portion irradiated with a laser when using a laser dicing sheet. The laser dicing sheet-peeling sheet laminate according to 1.   3. The laser dicing sheet-peeling sheet laminate according to claim 1, wherein the surface of the second sheet opposite to the side facing the first sheet has an arithmetic average roughness Ra of 0.3 μm or more. body.   4. The laser dicing sheet-peeling sheet laminate according to claim 1, wherein a surface of the second sheet that is opposite to the side facing the first sheet is a surface of a polyester film. 5. body.   The laser dicing sheet-release sheet laminate according to any one of claims 1 to 4, wherein the release sheet is a polyester film coated with a release agent.   The release sheet is composed of a long body, and the laser dicing sheet has a form of a wound body in which a plurality of the sheets are spaced apart from each other in the longitudinal direction of the release sheet and wound in the longitudinal direction. The laser dicing sheet-release sheet laminate according to any one of claims 1 to 5. A laser dicing sheet obtained by peeling the release sheet from the laser dicing sheet-release sheet laminate according to any one of claims 1 to 6,
The area overlapping the exposed area in the ring of the first sheet on the surface opposite to the side facing the first sheet of the pressure-sensitive adhesive layer is a plate-like member when the laser dicing sheet is used. A laser dicing sheet comprising a region to which is attached.   The radius of the inscribed circle in plan view of the in-ring exposed region of the first sheet is 2 mm or more larger than the radius of the circumscribed circle in plan view of the region to which the plate-like member is attached. The laser dicing sheet described in 1. The plate-like member is affixed to a predetermined region on the surface opposite to the side facing the first sheet in the pressure-sensitive adhesive layer of the laser dicing sheet according to claim 7 or 8,
The laser dicing sheet is irradiated with a laser so as to reach the plate-shaped member through the first sheet and the pressure-sensitive adhesive layer with the exposed area in the ring of the first sheet as the incident surface,
The chip member is obtained by separating the plate member into individual pieces by extending the laser dicing sheet to which the plate member after the laser irradiation is attached in the main surface direction. Chip body manufacturing method.

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