JP5771969B2 - Adhesive film for semiconductor wafer processing - Google Patents

Description

  The present invention relates to an adhesive film for processing semiconductor wafers.

  As a method for manufacturing a semiconductor device, flip chip mounting in which a semiconductor element is mounted on a circuit board by a face-down bonding method is performed. In general flip chip mounting, a bump electrode is formed on a semiconductor wafer, and then the back surface of the semiconductor wafer is ground to a predetermined thickness. During back grinding of the semiconductor wafer, a semiconductor wafer processing tape is used to fix and protect the semiconductor wafer. For example, in Patent Document 1 below, a wafer processing tape having a pressure-sensitive adhesive layer and an adhesive layer on a base film is prepared, and the processing tape is applied to the surface on which the protruding electrode of the semiconductor wafer is formed. A method for performing a back grinding process on a semiconductor wafer by bonding is described.

  In flip chip mounting, a film-like adhesive may be used for bonding a semiconductor chip and a circuit board. For example, in Patent Document 2 below, a semiconductor chip bonding sheet having a thermosetting resin layer provided on a synthetic resin film is manufactured, the thermosetting resin layer is pressure-bonded to the bump electrode surface of the semiconductor chip, and then synthesized. A method for peeling a resin film and connecting a semiconductor chip to a circuit board is described.

JP 2006-49482 A JP 2004-186204 A

  In the back grinding process of a semiconductor wafer, a wafer processing tape is supplied by a roll-to-roll method using a tape laminator or the like and is attached to the wafer by a pressure roller. Thereafter, the wafer processing tape is cut into a wafer shape by inserting and moving a cutter knife along the outer periphery of the wafer. At the time of cutting, it is common to cut and cut all the components constituting the wafer processing tape.

  A laminated semiconductor wafer processing adhesive film in which a pressure-sensitive adhesive layer and an adhesive layer are laminated on a base film can be used as a semiconductor wafer processing tape and a semiconductor chip bonding sheet. However, such an adhesive film for processing a semiconductor wafer has different characteristics such as a function as a protective film on the electrode surface side in a back grinding process of a semiconductor wafer and a function as an adhesive for flip chip mounting. The physical properties of each layer may differ greatly. In particular, in order for the adhesive layer to exhibit a function as an adhesive for flip chip mounting, it is necessary to satisfy the solder reflow resistance and the durability against a thermal shock test required for a semiconductor device after mounting. For this reason, the adhesive layer has a higher hardness than the base film and the pressure-sensitive adhesive layer, and may have fragile physical properties. When a wafer processing tape including such an adhesive layer is cut out with a cutter knife, there is a problem that burrs are formed or cutting wastes are easily generated. When the back grinding operation of the wafer is performed with these remaining on the wafer, there arises a problem that the uniform and flat thinning process of the wafer is impaired, and in some cases, the wafer is damaged.

  Further, the cutting ability of the cutter knife is deteriorated due to wear. The adhesive film for processing a semiconductor wafer having a function as a mounting material has a problem that the life of the cutter knife is further shortened because it has an adhesive layer with high hardness.

  Furthermore, when cutting out an adhesive film for processing semiconductor wafers after lamination, the conventional processing film is cut out approximately the same as the wafer along the outer periphery of the wafer by a cutter knife. At that time, the wafer and the cutter knife come into contact with each other. Since defects such as chipping and cracking of the wafer, wear and breakage of the cutter knife occur, the cutting size may be larger than the wafer size so that the wafer and the cutter knife do not directly contact each other. However, when the dicing tape is attached to the back surface of the wafer in the subsequent dicing step, there is a problem that the portion of the cut out processing film that sticks out from the wafer surface sticks to the dicing tape and prevents the back grind tape from being peeled off.

  Further, in the back grinding process of the semiconductor wafer, it is necessary that the load is evenly applied to the entire surface of the wafer. For this reason, the wafer processing tape is required to be attached to the wafer without biting air voids or the like. However, in order to attach to a semiconductor wafer on which convex electrodes are formed without air voids, the convex shape is applied by mechanical pressure such as a pressure roller or pressurization by air pressure in a state where the viscosity of the tape is lowered by heating. It is necessary to attach the air void around the electrodes so that no air void bites occur. However, when the wafer processing tape on which the pressure-sensitive adhesive layer and the adhesive layer are formed is heated and pressurized, component diffusion of the pressure-sensitive adhesive layer and the adhesive layer may occur and fusion may occur. For this reason, there is a problem that it becomes difficult to peel off the base film and the pressure-sensitive adhesive layer from the adhesive layer after the back grinding treatment. Furthermore, since the component transfer between the pressure-sensitive adhesive layer and the adhesive layer occurs even during long-term storage, peeling becomes more difficult. Even when peeled off, there is a problem that the properties as an adhesive are hindered by the component transfer of the adhesive component into the adhesive.

  Generally, the adhesive film is formed by applying the film adhesive composition to a base film for coating such as a synthetic resin film, but the base film needs to be peeled off later, A release treatment layer is provided on the coated surface of the base film with a silicone release agent. However, when applied to a base film with a silicone release agent, if the release agent has a high release ability, separation between the adhesive layer and the base film occurs during the back grinding process. On the other hand, there is a problem that back grinding cannot be performed. On the other hand, if the releasing force of the silicone treatment agent is weak, there is a problem that the silicone treatment agent is transferred and the adhesive properties of the adhesive layer are deteriorated. In addition, if the adhesive composition is applied to a base film that is not subjected to a mold release treatment, it may be difficult to peel off the base film, or even if part of the adhesive layer is peeled off. The problem of peeling off occurs.

  Therefore, the present invention can solve the problems in the back grinding process, and can easily peel off the base film from the adhesive layer, and an adhesive film for semiconductor processing in which the performance of the adhesive layer is hardly deteriorated. The purpose is to provide.

  The present invention is an adhesive film used for processing a semiconductor wafer, comprising a release layer, an adhesive layer, a separation layer, and a base film in this order on a carrier tape, the adhesive layer, the separation layer And an adhesive film for semiconductor processing, characterized in that the base film is formed in a wafer shape having substantially the same size as the semiconductor wafer to be processed.

  In the adhesive film for processing a semiconductor wafer of the present invention, the adhesive layer, the separation layer, and the base film are formed in a wafer shape with substantially the same size as the semiconductor wafer. After pasting, cutting into a semiconductor wafer shape with a cutter knife or the like is no longer necessary, and the cutting process is omitted, and burrs and cutting debris are not generated, so uniform and flat processing can be performed in thinning grinding of the backside of a semiconductor wafer. There is an effect. Further, by providing a separation layer between the adhesive layer and the base film, both the retention during back grinding and the peelability of the base film can be achieved.

  In the adhesive film for processing a semiconductor wafer of the present invention, the cohesive force of the separating layer is smaller than the cohesive force of the adhesive layer, that is, the cohesive force of the separating layer and the cohesive force of the adhesive layer are less than the cohesive force of the separating layer <adhesion The relationship between the cohesive strength of the agent layer is preferable. In this case, when the adhesive layer is attached to the adherend and the base film is peeled off, the interface between the separation layer and the adhesive layer is peeled off and / or the separation layer is cohesive and / or the separation layer. Can be separated by peeling off the interface between the substrate film and the substrate film, so that the effect of easily peeling the substrate film can be obtained more effectively, and the adhesive layer as designed on the adherend can be more reliably secured. The effect that it can be left in is obtained.

  In the adhesive film for semiconductor wafer processing of the present invention, the adhesive layer comprises a resin composition comprising at least a thermosetting resin, a high molecular weight component, and a compound for initiating a crosslinking reaction of the thermosetting resin, and It is preferable to contain a filler. In this case, a sufficiently reliable cured product can be obtained after heat curing, and the durability to solder reflow resistance and thermal shock test required for a semiconductor device after flip chip mounting can be satisfied. The effect can be obtained more effectively.

  Furthermore, the separation layer preferably contains a resin composition comprising at least a thermosetting resin, a high molecular weight component, and a compound for promoting a crosslinking reaction of the thermosetting resin. In this case, compatibility with the composition of the adhesive resin layer can be improved, and even when the separation layer cohesively breaks and remains on the adhesive layer, the effect of not hindering the adhesive ability of the adhesive layer can be obtained. it can.

  In the adhesive film for processing a semiconductor wafer of the present invention, the adhesive layer is an adhesive for an adhesive film for processing a semiconductor wafer in which the carrier tape and the release layer are removed on the protruding electrode side of the semiconductor wafer provided with the protruding electrode. The thickness of the adhesive layer when the layers are laminated is formed so as to be larger than the height of the protruding electrode, and the height of the circuit electrode on the circuit board to which the semiconductor chip obtained from the semiconductor wafer is flip-chip connected and the protruding It is preferably formed with a thickness that is greater than the sum of the height of the electrodes. In this case, when the adhesive film for processing a semiconductor wafer is attached to the convex electrode forming surface of the semiconductor wafer, the convex electrode can be embedded to obtain a flat state. The effect of preventing the occurrence of unevenness is obtained, and further, the effect that the circuit of the target semiconductor device can be sufficiently filled when the base film is peeled off to perform the flip chip connection is obtained.

  In the adhesive film for processing a semiconductor wafer of the present invention, the separation layer and the adhesive layer have thermosetting properties, and the viscosity at 20 ° C. or more and less than 40 ° C. before heat curing is 150000 Pa · s or less. preferable. In this case, when the base film is peeled off from the processing adhesive film affixed to the semiconductor chip and temporarily fixed to the circuit board or the like, the adhesive layer or a part of the adhesive layer and the separation layer on the circuit board mounting surface Alternatively, the separation layer can be sufficiently brought into contact with the substrate surface for good adhesion, and the semiconductor chip can be stably fixed temporarily.

  ADVANTAGE OF THE INVENTION According to this invention, while solving the problem in the back grinding process mentioned above, the base film can be easily peeled off from an adhesive layer, and the adhesive film for semiconductor processing which does not generate | occur | produce the performance deterioration of an adhesive layer easily Can be provided. The adhesive film for semiconductor processing of the present invention enables uniform and flat back grinding of a semiconductor wafer, and is suitable for a semiconductor wafer back grinding process, a semiconductor wafer dicing process, and a semiconductor chip flip chip mounting.

(A) is a schematic cross section which shows suitable one Embodiment of the adhesive film for semiconductor wafer processing of this invention, (b) is the top view which looked at the film from the base film side, (c) ) Is a schematic cross-sectional view for explaining semiconductor wafer processing according to the present invention. It is a schematic cross section which shows the laminated body which laminated the adhesive bond layer of the adhesive film for semiconductor wafer processing of this embodiment from which the carrier tape and the release layer were removed on the circuit surface of a semiconductor wafer. (A) is explanatory drawing which shows the back grinding process of the laminated body of FIG. 2, (b) is a schematic cross section which shows the laminated body by which the back surface of the semiconductor wafer was ground. It is a schematic cross section which shows the state which set the laminated body shown to (b) of FIG. 3 to the dicing frame. It is a schematic cross section which shows the dicing process of dicing the laminated body shown to (b) of FIG. It is a schematic cross section for demonstrating the process of removing a base film and a part of separated layer from the diced laminated body. It is a schematic cross section for demonstrating the process of removing a base film and a part of separated layer from the diced laminated body. It is a schematic cross section which shows the process of picking up the semiconductor chip obtained by dicing. It is a schematic cross section which shows the process of flip-chip mounting the picked-up semiconductor chip on a circuit board. It is a schematic cross section showing one embodiment of a semiconductor device obtained by flip chip mounting a semiconductor chip concerning an embodiment on a circuit board. It is a schematic cross section which shows the other example of the dicing process in the semiconductor wafer processing which concerns on this invention.

  Hereinafter, with reference to the drawings, an adhesive film for processing a semiconductor wafer according to the present invention, semiconductor wafer processing (a semiconductor wafer back grinding method, a semiconductor wafer dicing method) and a semiconductor chip according to the present invention which are performed using the same Preferred embodiments of the mounting method and the semiconductor device manufacturing method will be described in detail.

  (A) of FIG. 1 is a schematic cross-sectional view showing a preferred embodiment of an adhesive film for processing a semiconductor wafer of the present invention, and (b) is a top view of the film as viewed from the base film side. (C) is a schematic cross section for demonstrating the semiconductor wafer processing which concerns on this invention.

  An adhesive film F1 for processing a semiconductor wafer shown in FIG. 1A includes an adhesive layer 3, a separation layer 2, and a base material on a release layer 4 of a carrier film 5 having a release layer 4 formed on one side. The film 1 is formed in this order. FIG. 1B is a top view of the film F1 viewed from the base film 1 side. As shown in FIG. 1B, the adhesive layer 3, the separation layer 2, and the base film 1 are formed. The wafer is formed in the shape of a wafer substantially the same size as the semiconductor wafer to be processed. In addition, the adhesive bond layer 3, the separation layer 2, and the base film 1 may be formed on the carrier film in a state in which a portion other than the portion used for wafer pasting is removed.

  First, semiconductor wafer processing according to the present invention will be described. A semiconductor wafer 10 as shown in FIG. 1C is prepared. The semiconductor wafer 10 has a circuit surface (main surface) S1 on which a circuit is formed by a semiconductor process, and a back surface S2 that is a surface opposite to the circuit surface S1. A plurality of protruding electrodes 10 a protruding from the circuit surface S 1 are formed on the circuit surface S 1 of the semiconductor wafer 10. In addition, the thickness of the semiconductor wafer 10 at this time is in a state before back grinding, and is usually about 550 μm to 750 μm.

  Subsequently, an adhesive film F1 for processing a semiconductor wafer shown in FIG. 1 (a) is prepared, and the carrier film 5 is peeled from the film with a release layer 4 to expose the adhesive layer 3. The tape F1a is attached to the circuit surface S1 of the semiconductor wafer 10 with the adhesive layer 3 side facing the circuit surface S1 of the semiconductor wafer 10. The processing tape F1a can be attached to the semiconductor wafer 10 using, for example, a laminator in which a heating mechanism is applied to a stage and a pressure roll, or a laminator having a heating mechanism, a suction mechanism, and a pressure roll mechanism. .

  At this time, the base material film 1 is pressurized at a predetermined pressure, so that the adhesive layer 3 is filled so as to fill the space between the protruding electrodes 10a. Thus, an adhesive layer that embeds the protruding electrode on the circuit surface S1 of the semiconductor wafer 10 is formed (adhesive layer forming step). And, as shown in FIG. 2, the adhesive layer 3 after sticking embeds the protruding electrode 10a, and is further attached with the adhesive layer remaining on the protruding electrode. A laminated body formed flat is obtained. The base film 1 is a soft base material that can be deformed.

  In the adhesive layer forming step, when the adhesive film is attached, it is preferable to perform embedding by heating and pressurization so that air voids do not occur at the interface between the semiconductor wafer and the adhesive layer. In the present embodiment, since the grinding process can be performed without attaching the back grind tape after the adhesive layer forming process, the back grind process can be shortened.

  Furthermore, since the base film, the separation layer, and the adhesive layer are formed substantially the same as the outer shape and size of the semiconductor wafer, the adhesive film of the present embodiment is cut out substantially the same as the semiconductor wafer after the adhesive film is attached. Therefore, the thinning grinding of the backside of the semiconductor wafer can be processed uniformly and flatly without generating burrs or cutting waste.

  Subsequently, as shown in FIG. 3, the semiconductor wafer is ground from the back surface S2 side by the back surface grinding device 12 (back grinder) while applying pressure to the base film, thereby reducing the thickness of the semiconductor wafer. The back grinding is performed using a general back grinding apparatus. Specifically, the semiconductor wafer is ground so that the thickness of the semiconductor wafer is about 50 μm to 550 μm (grinding step). Here, since the said processing tape F1a is affixed on the circuit surface S1 side of a semiconductor wafer, a pressure can be applied uniformly. As a result, the back surface S2 of the semiconductor wafer can be planarized by grinding. Moreover, damage to the semiconductor wafer during back grinding can be suppressed by the processing tape F1a. In this manner, a laminated body R1 including the thinned semiconductor wafer and the processing tape F1a attached to the circuit surface S1 is manufactured.

  Subsequently, as shown in FIG. 4, with the processing tape F1a still attached to the circuit surface S1 side of the semiconductor wafer, dicing is performed on the back surface S2 side of the laminate R1 and the lower edge 14a of the dicing frame 14. A tape 16 is applied. Fixing to the dicing tape 16 is performed by a general dicing tape sticking device, and the dicing frame 14 is an annular metal member, and is used as a semiconductor wafer fixing jig when dicing the semiconductor wafer. The inner diameter of the dicing frame 14 is larger than the outer shape of the semiconductor wafer, and is arranged on the dicing tape so as to surround the semiconductor wafer. Moreover, the dicing tape 16 has the base film 16a and the adhesion layer 16b formed in the surface of the base film 16a. As the dicing tape 16, a commercially available dicing tape is used.

  Although not shown, a positioning pattern for positioning the dicing position by the dicing blade DB is formed on the circuit surface S1 of the semiconductor wafer. During dicing, the semiconductor wafer is cut through the processing tape F1a. Since the position is confirmed, the adhesive film according to the present invention preferably has a transmittance that allows the positioning pattern to be visually recognized (for example, the visible light transmittance of the entire adhesive film F1 is 20% or more).

  Subsequently, as shown in FIG. 5, the semiconductor wafer is diced from the adhesive film side together with the processing tape F1a by the dicing blade DB with the circuit surface S1 of the semiconductor wafer facing upward (so-called face-up dicing). And a plurality of semiconductor chips 30 (dicing step). Here, by employing face-up dicing, the dicing position can be positioned relatively easily using the positioning pattern.

  In the dicing step, dicing is performed without removing the base film from the laminate R1, so that the semiconductor wafer can be prevented from being contaminated by chips generated by dicing. Dicing is performed using a general dicing apparatus.

  Subsequently, as shown in FIG. 6, a peeling adhesive tape 26 for peeling the substrate film is attached to the entire surface of the singulated substrate film. FIG. 7 shows that when the peeling adhesive tape 26 is pulled and the base film 1 is peeled off, the separation layer 2 is coherently broken, partly remains on the surface of the adhesive layer 3a, and partly on the base film 1 It shows the state of being peeled off. The base film shown in FIGS. 6 and 7 is peeled off using a peeling device for peeling back grind tape.

  Thereafter, although details are omitted, after the adhesive force of the adhesive layer 16b of the dicing tape 16 is reduced by irradiation with ultraviolet rays or the like, the adhesive layer 3a and the separation layer 2 are formed on the circuit surface S1, as shown in FIG. Each of the semiconductor chips 30 having a part thereof is picked up one by one.

  Next, the semiconductor chip 30 having a part of the adhesive layer 3a and the separation layer 2 is connected on the circuit board. FIG. 9 shows a state in which a circuit board 40 having a semiconductor chip 30 separated from a semiconductor wafer and a circuit 42 opposite to the semiconductor chip 30 is prepared. Here, the adhesive layer 3 a on the semiconductor chip has a sufficient height with respect to the gap between the semiconductor devices formed by the protruding electrodes 10 a and the circuit electrodes 42. Furthermore, alignment with the circuit substrate 40 having the circuit electrodes 42 facing the separated semiconductor chip 30 is also performed by recognizing the alignment mark on the semiconductor chip via the adhesive layer. Further, since the separation layer 2 remaining when the base film is peeled off adheres to the adhesive layer 3a, the semiconductor chip 30 can be easily temporarily fixed to the circuit board 40.

  Thus, the semiconductor device 50 in which the semiconductor chip 30 and the circuit board 40 are connected via the adhesive layer as shown in FIG. 10 is obtained. This connection is performed by heating and pressurizing using a flip chip connection device, and a semiconductor device including the semiconductor chip can be obtained.

  In addition, although the suppression effect with respect to the contamination by the above chips cannot be obtained, as shown in FIG. 11, the base film and a part of the separation layer are removed from the laminated semiconductor wafer to which the dicing tape is attached. Dicing may be performed after the removal.

  The thickness of the adhesive layer is maintained as originally designed by the cohesive failure of the separation layer in the peeling process of the base film, and the adhesive layer and the separation layer partially remaining on the surface of the adhesive layer are composed. In particular, the compatibility is good, and the adhesive property of the adhesive layer is not hindered, and a highly reliable semiconductor device can be obtained.

  The adhesive film for semiconductor wafer processing of this embodiment will be further described. The adhesive film F1 for processing a semiconductor wafer includes, for example, a carrier film 5 having a release layer 4 formed on one surface and an adhesive layer 3 formed on a carrier film 5 and a base film 1 having a separation layer 2 formed thereon. The adhesive layer 3 and the separation layer 2 can be formed by laminating at room temperature or warming so as to bond them together. Moreover, the adhesive film F1 for semiconductor wafer processing is separated on the adhesive layer 3 formed by, for example, applying an adhesive composition to the carrier film 5 having the release layer 4 formed on one side and then drying. The separation layer 2 can be formed by applying the layer composition and then drying, and the substrate film 1 can be formed on the separation layer 2 by laminating at room temperature or warming. Furthermore, the adhesive film F1 for semiconductor wafer processing is dried after applying the adhesive composition on the separation layer 2 formed by applying the separation layer composition to the base film 1 and drying it, for example. The adhesive layer 3 is formed by the above process, and the carrier film 5 having the release layer 4 formed on one side is laminated on the adhesive layer 3 by room temperature heating or lamination.

  The adhesive film F1 for processing a semiconductor wafer is formed on a carrier film 5 having a release layer 4 in a state in which an adhesive layer, a separation layer, and a base film are punched into a wafer shape with approximately the same size as a semiconductor wafer. Has been. The adhesive layer, the separation layer, and the base film may be formed on the carrier film in a state in which a portion other than the portion used for wafer pasting is removed.

  The adhesive layer is solid at room temperature because it is necessary to maintain the flatness of the wafer in the back grinding process. The adhesive layer is bonded to the surface of the wafer where the protruding electrodes are formed by pressing, holding the wafer during the back grinding process, protecting the circuit surface during the dicing process, and bonding and connecting the circuit chip and circuit board in flip chip bonding I do. At the time of bonding to the wafer, it is necessary to follow the unevenness of the wafer circuit surface and to bring the adhesive layer and the wafer interface into close contact with each other without biting in the air voids. For this reason, at the time of bonding, a viscosity falls and the followability to a shape must be improved. The bonding temperature is preferably lower than the temperature at which the reaction of the thermosetting resin in the adhesive layer does not start, and preferably higher than room temperature. In addition, it is desirable to apply at a low temperature from the viewpoint of preventing the wafer from warping due to heat shrinkage of the adhesive layer. A desirable pasting temperature is 30 ° C to 90 ° C, more desirably 40 ° C to 80 ° C, and more desirably 50 ° C to 70 ° C. The viscosity of the adhesive layer decreases at the application temperature, and the viscosity is desirably 1000 Pa · s or more and 10,000 Pa · s or less. When the viscosity exceeds 10,000 Pa · s, it is not preferable because pressurization or the like must be performed in order to follow the unevenness of the wafer and bring the interface into close contact with each other. When the viscosity is less than 1000 P · s, the protrusion from the side surface of the wafer occurs at the time of bonding, and it is not preferable because the amount of adhesive cannot be controlled.

  The adhesive layer needs to be highly elastic in order to hold the wafer during the back grinding process. The adhesive layer preferably has an elastic modulus of 1 GPa or more at room temperature. When the elastic modulus at room temperature is less than 1 GPa, it is not preferable because the flatness of the wafer cannot be maintained due to the occurrence of elongation or deformation.

  Furthermore, in the dicing process, the adhesive layer needs to be in close contact without being peeled off from the wafer surface when divided by a blade or divided after stealth dicing. In addition, since the film must be divided by following the wafer at the time of division, it is necessary to have high elasticity. Also from this viewpoint, the elastic modulus at room temperature is preferably 1 GPa or more. Moreover, it is desirable that the adhesive layer contains a filler in order to increase the elasticity, suppress burrs, and improve the separation property. It is necessary to be able to observe the alignment pattern formed on the chip circuit surface in the chip circuit surface during the recognition of the scribe line of the semiconductor wafer during the dicing process or through the flip chip connection process. The transmittance according to the turbidity measurement of the layer is preferably 10% or more. The refractive indexes of the filler and the adhesive layer are preferably approximate values so as not to hinder the transmittance of the adhesive layer. From the viewpoint of preventing the transmittance from being hindered, the filler preferably has a difference between the refractive index of the adhesive layer and the refractive index of the filler in a range of ± 0.06.

  The adhesive layer has a resin composition comprising at least a thermosetting resin, a high molecular weight component, and a compound for initiating a crosslinking reaction of the thermosetting resin, and a refractive index difference between the resin composition is ± Those comprising a filler in the range of 0.06 are preferred.

  As the thermosetting resin, those that are cured by three-dimensional crosslinking with heat are preferably used. A high molecular weight component that is solid at room temperature and improves the film-forming property of the adhesive layer and is softened by heating is preferably used. The initiator for initiating the crosslinking reaction is solid or liquid, and promotes the reaction between the thermosetting resin and the thermosetting resin during heating to cause the crosslinking reaction, while working from room temperature to the application temperature. Those that do not react at temperature, or that have a slow reaction rate and can maintain the state of reactivity until the adhesiveness at the time of flip-chip connection is sufficiently developed are preferably used. As the filler, those that increase the cohesive force when the resin composition is uncured and reduce the linear expansion coefficient after curing are preferably used.

  The thickness of the adhesive layer is preferably such that the adhesive layer can sufficiently fill the space between the semiconductor chip and the circuit board. The adhesive layer preferably has a thickness larger than the height of the protruding electrode even when the protruding electrode of the semiconductor wafer is embedded. Usually, if the thickness of the adhesive layer is equivalent to the sum of the height of the protruding electrode and the height of the wiring of the circuit board, the space between the semiconductor chip and the circuit board can be sufficiently filled. More preferably, the thickness of the adhesive layer is larger than the sum of the height of the circuit electrode of the circuit board and the height of the protruding electrode.

  Examples of the separation layer that is solid at room temperature include those containing a resin composition comprising at least a thermosetting resin, a high molecular weight component, and a compound for initiating a crosslinking reaction of the thermosetting resin.

  As the thermosetting resin, those that are cured by three-dimensional crosslinking with heat are preferably used. A high molecular weight component that is solid at room temperature and improves the film-forming property of the adhesive layer and is softened by heating is preferably used. The initiator for initiating the crosslinking reaction is solid or liquid, and promotes the reaction between the thermosetting resin and the thermosetting resin during heating to cause the crosslinking reaction, while working from room temperature to the application temperature. Those that do not react at temperature, or that have a slow reaction rate and can maintain the state of reactivity until the adhesiveness at the time of flip-chip connection is sufficiently developed are preferably used.

  Since the separation layer is provided, the separation of the separation layer and the substrate, the cohesive failure of the separation layer, and the separation of the separation layer and the adhesive layer can be performed in the step of peeling the substrate film after the back grinding process. Alternatively, the substrate film can be peeled off in a single or mixed failure mode, whereby the substrate film can be peeled off without peeling off the adhesive layer from the wafer. After being peeled off from the adhesive layer with breakage of the separation layer, it is necessary to permeate the adhesive layer and recognize the scribe lines or alignment marks on the wafer circuit surface. Since the unevenness of the layer causes irregular reflection and the recognizability is lowered, it is not preferable. On the other hand, although there is no problem when the separation layer is too thin, it is difficult to ensure a uniform coating state. From these viewpoints, the thickness of the separation layer is preferably 1 micron or more and 5 microns or less, and more preferably 1 micron or more and 3 microns or less.

  In the present embodiment, the relationship between the cohesion force of the separation layer and the adhesive layer is preferably the cohesion force of the separation layer <the cohesion force of the adhesive layer. When the cohesive force of the separation layer is larger than the cohesive force of the adhesive layer, there is a risk of cohesive failure of the adhesive layer when the base film is peeled off, which is not preferable. The relationship between the cohesive force of the separating layer and the adhesive layer can be set such that the cohesive force of the separating layer <the cohesive force of the adhesive layer by changing the amount and type of the compounding components. For example, by setting the molecular weight of the high molecular weight component as a separation layer <adhesive layer, setting the amount of the liquid component contained in the resin composition as the separation layer> adhesive layer, and adding a filler to the adhesive layer Can be achieved. When the cohesive force of the separation layer and the adhesive layer is the separation layer = the adhesive layer and the separation layer> the adhesive layer, a part of the adhesive layer from the separation layer side when the substrate film is peeled off Or the whole thickness direction is extracted, resin filling at the time of flip chip connection becomes insufficient, and the reliability of the semiconductor device is impaired, which is not preferable.

  The following methods can be cited as a method for comparing the cohesive forces of the separation layer and the adhesive layer at the time of designing for providing a difference in cohesive force between the separation layer and the adhesive layer. For example, after applying the separation layer forming composition for forming the separation layer and the adhesive layer forming composition for forming the adhesive layer to the coating film substrate subjected to the release treatment, respectively. Dry to produce films each formed of a single layer. Then, by performing a tensile measurement with a tensile tester such as Tensilon, the cohesive forces of the separation layer and the adhesive layer can be compared. As another method, a coating film base in which a release treatment is applied to a separation layer forming composition for forming a separation layer and an adhesive layer forming composition for forming an adhesive layer, respectively. Examples of the method of measuring the elastic modulus at room temperature by applying a frequency in a tensile mode using a viscoelasticity measuring apparatus for a film prepared by drying after coating on a material. Since the frequency is a relative evaluation, it is sufficient that the comparison target is the same, and an arbitrary frequency can be selected. As another method, comparison can be made by measuring the elastic modulus at room temperature by applying a frequency in the shear mode to the film produced above using a shear viscoelasticity measuring device. Since the frequency is a relative evaluation, it is sufficient that the comparison target is the same, and an arbitrary frequency can be selected.

  Furthermore, as another method, after producing the laminated body which laminated | stacked the separation layer and the adhesive layer in order on the base film, the adhesive layer of this laminated body is affixed on a semiconductor wafer, and a base film is peeled off or adhere | attached After fixing the agent layer to the appropriate base material surface with double-sided tape, the base film is peeled off, and the method by measuring the thickness of the resin remaining on the base film with a device such as a micrometer is measured. Can be mentioned. If the thickness of the remaining resin is equal to or less than the thickness of the separation layer when applied to the substrate film, the cohesive force relationship is separation layer <adhesive layer, and the resin remaining on the substrate film Can be determined that the cohesive force relationship is separation layer = adhesive layer or separation layer> adhesive layer.

  Examples of polymers that can be selected as the base film 1 include polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, poly-4-methylpentene-1, ethylene-vinyl acetate copolymer, and ethylene-acrylic acid. Homopolymers or copolymers of α-olefins such as ethyl copolymer, ethylene-methyl acrylate copolymer, ethylene-acrylic acid copolymer, ionomer, or mixtures thereof, polyethylene terephthalate, polycarbonate, polymethyl methacrylate, etc. Engineering plastics, polyurethanes, thermoplastic elastomers such as styrene-ethylene-butene or pentene copolymers, polyamide-polyol copolymers, and mixtures thereof.

  Examples of polymers that can be selected as the carrier film 5 include polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, poly-4-methylpentene-1, ethylene-vinyl acetate copolymer, and ethylene-ethyl acrylate. Engineering such as copolymers, ethylene-methyl acrylate copolymers, ethylene-acrylic acid copolymers, α-olefin homopolymers or copolymers such as ionomers or mixtures thereof, PET, polycarbonate, polymethyl methacrylate, etc. Listed are plastic elastomers, thermoplastic elastomers such as polyurethane, styrene-ethylene-butene or pentene copolymers, polyamide-polyol copolymers, and mixtures thereof. Specifically, for example, a PET base material in which the release layer 4 is formed on the surface with a silicone-based release treatment agent can be mentioned. In addition, when the adhesive resin composition is applied to a carrier film on which a release layer is not formed, it is difficult to peel off the carrier film, or even if part of the adhesive resin composition is peeled off, The problem of peeling off also occurs. On the other hand, when the release layer is formed on the carrier film, the carrier film can be easily peeled from the adhesive layer.

  Although the thickness of the mold release layer 4 is not specifically limited, It is preferable that it is 50 micrometers or less, and it is more preferable that it is 0.5-5 micrometers. When the thickness is smaller than 0.5 μm, the uniform distribution of the release layer is impaired and the releasability is lowered, which is not preferable. When the thickness is larger than 5 μm, there is no particular problem. However, the thickness is still more preferably 3 μm or less from the viewpoint of preventing the release treatment agent from transferring and deteriorating the adhesive properties of the adhesive layer.

  Examples of thermosetting resins used for the separation layer 2 and the adhesive layer 3 include epoxy resins, bismaleimide resins, triazine resins, polyimide resins, polyamide resins, cyanoacrylate resins, phenol resins, unsaturated polyester resins, and melamine resins. , Urea resin, polyurethane resin, polyisocyanate resin, furan resin, resorcinol resin, xylene resin, benzoguanamine resin, diallyl phthalate resin, silicone resin, polyvinyl butyral resin, siloxane modified epoxy resin, siloxane modified polyamideimide resin, acrylate resin, etc. It is done. These can be used alone or as a mixture of two or more. The thermosetting resin used for the separation layer 2 and the adhesive layer 3 may be the same type or different types, but is preferably a thermosetting resin having the same reaction mechanism, storage stability, and reaction temperature. Preferably there is.

  The high molecular weight component is preferably a polymer that becomes a solid state at room temperature and softens by heating, and has a weight average molecular weight of 10,000 or more. Examples of such a high molecular weight component include polyester resin, polyether resin, polyamide resin, polyamideimide resin, polyimide resin, polyarylate resin, polyvinyl butyral resin, polyurethane resin, phenoxy resin, polyacrylate resin, polybutadiene, and acrylonitrile butadiene. Examples thereof include a polymer (NBR), an acrylonitrile butadiene rubber styrene resin (ABS), a styrene butadiene copolymer (SBR), and an acrylic acid copolymer. These can be used alone or in combination of two or more. In addition, these high molecular weight components may have a functional group that reacts with a thermosetting resin at a side chain or at a terminal. Examples of such functional groups include epoxy groups, phenolic hydroxyl groups, alcoholic hydroxyl groups, carboxyl groups, and amines. These functional groups may be capped with their reactivity suppressed by a protective group that cleaves during the reaction or steric hindrance.

  The compound for initiating the crosslinking reaction is preferably a compound having the potential to achieve both high reactivity and storage stability of the thermosetting resin. The potential is, for example, protection by microcapsules, widening the difference between decomposition temperature and storage temperature, and having a melting point and solidity during storage and melting during reaction, so that the reactivity is expressed. Storage temperature and melting temperature It can be expressed by a method such as widening the difference between them, or introducing a protecting group that cleaves at the reaction temperature to make it stable during storage. The microcapsule type hardener is made of, for example, a polymer material such as polyurethane, polystyrene, gelatin and polyisocyanate with a hardener as a core, inorganic materials such as calcium silicate and zeolite, and a metal thin film such as nickel and copper. It is substantially covered and has an average particle size of 10 μm or less, preferably 5 μm or less.

  As the compound for initiating the crosslinking reaction, a compound optimal for the reaction mechanism of the thermosetting resin can be selected. For example, when the thermosetting resin is an epoxy resin, an imidazole or amine compound can be selected for promoting the polymerization. When crosslinking proceeds by an addition reaction, a polymerization catalyst such as triphenylphosphine or DBU can be used. In addition to this, the resin composition includes phenolic, imidazole, hydrazide, thiol, benzoxazine, boron trifluoride-amine complex, sulfonium salt, amineimide, polyamine as a component that reacts with the three-dimensional crosslinkable resin. A salt, dicyandiamide, or an organic peroxide compound may be included. These curing agents may be microencapsulated by coating with a polyurethane-based or polyester-based polymer substance in order to increase the pot life.

  The filler may be crystalline or non-crystalline. Since the cohesive force can be improved by adding a filler to the adhesive layer, it is easy to provide a cohesive force difference from the separation layer. Moreover, the linear expansion coefficient after hardening of an adhesive bond layer can be made small by a filler. When the linear expansion coefficient is small, thermal deformation is suppressed. Therefore, even after the semiconductor chip manufactured from the semiconductor wafer 10 is mounted on the circuit board, the electrical connection between the protruding electrode and the wiring of the circuit board can be maintained, so that the semiconductor chip and the circuit board are connected. By doing so, the reliability of the manufactured semiconductor device can be improved.

The filler described above may be a filler having a chemical composition expressed as a single compound or a filler having a plurality of compositions. Examples of fillers expressed as a single compound include oxide fillers such as silica, alumina, titania and magnesia, hydroxide fillers such as aluminum hydroxide and magnesium hydroxide, and sulfates such as barium sulfate and sodium sulfate. A filler etc. are mentioned. Examples of fillers expressed as a compound having a plurality of compositions include zinc, aluminum, antimony, ytterbium, yttrium, indium, erbium, osmium, cadmium, calcium, potassium, silver, chromium, cobalt, samarium, dysprosium, zirconium, Tin, cerium, tungsten, strontium, tantalum, titanium, iron, copper, sodium, niobium, nickel, vanadium, hafnium, palladium, barium, bismuth, praseodymium, beryllium, magnesium, manganese, molybdenum, europium, lanthanum, phosphorus, lutetium, Examples thereof include oxides containing metal elements such as ruthenium, rhodium and boron. These can also be mixed and used. The composite oxide preferably contains two or more kinds of metals as raw materials, and is a compound having a structure different from the structure when the raw metal becomes an oxide alone. Particularly preferred are composite oxide particles comprising an oxide compound containing at least one metal element selected from aluminum, magnesium or titanium and two or more other elements as raw materials. Examples of such complex oxides include aluminum borate, cordierite, false light, and mullite. The linear expansion coefficient of the composite oxide particles is preferably 7 × 10 ⁻⁶ / ° C. or less, more preferably 3 × 10 ⁻⁶ / ° C. or less, in the temperature range of 0 ° C. to 700 ° C. or less. A large thermal expansion coefficient is not preferable because a large amount of composite oxide particles need to be added to lower the thermal expansion coefficient of the adhesive layer.

  The separation layer and the adhesive layer may contain an additive such as a coupling agent. Thereby, the adhesiveness of a semiconductor chip and a wiring board can be improved.

  Conductive particles may be dispersed in the adhesive layer. In this case, it is possible to reduce an adverse effect due to variations in the height of the protruding electrode. Further, the connection can be maintained even when the wiring board is not easily deformed due to compression, such as a glass substrate. Furthermore, the adhesive layer can be an anisotropic conductive adhesive layer.

  The semiconductor wafer to which the adhesive film for processing a semiconductor wafer of the present invention is applied can obtain a semiconductor chip after the dicing process. The semiconductor chip has a protruding connection terminal. The protruding connection terminal of the semiconductor chip is formed by a gold stud bump formed using a gold wire, a metal ball fixed to the electrode of the semiconductor chip by a thermocompression bonding or ultrasonic thermocompression bonding machine, or plating or vapor deposition. May be good. The protruding connection terminal does not need to be made of a single metal, and may contain a plurality of metal components such as gold, silver, copper, nickel, indium, palladium, tin, and bismuth. May be laminated. Further, the semiconductor chip having the protruding connection terminal may be in the state of a semiconductor wafer having the protruding connection terminal.

  The semiconductor chip and the circuit board are aligned in order to dispose the protruding connection terminals of the semiconductor chip and the substrate on which the wiring pattern is formed. For alignment, the semiconductor chip may have an alignment mark on the same surface as the protruding connection terminal.

  The circuit board on which the wiring pattern is formed may be a normal circuit board or a semiconductor chip. In the case of circuit boards, the wiring pattern is formed on the surface of an insulating substrate such as a substrate formed by impregnating glass cloth or nonwoven fabric with an epoxy resin or a resin having a benzotriazine skeleton, a substrate having a build-up layer, polyimide, glass, ceramics, etc. An unnecessary portion of a metal layer such as copper formed can be removed by etching, can be formed on the surface of the insulating substrate by plating, or can be formed by vapor deposition. Moreover, the wiring pattern does not need to be formed of a single metal, and may contain a plurality of metal components such as gold, silver, copper, nickel, indium, palladium, tin, and bismuth. May be laminated. When the substrate is a semiconductor chip, the wiring pattern is usually made of aluminum, but a metal layer such as gold, silver, copper, nickel, indium, palladium, tin, or bismuth may be formed on the surface thereof. .

  Back grinding of a semiconductor wafer is performed using a commercially available back grinding apparatus after the adhesive film for processing a semiconductor wafer of the present invention is attached to the circuit surface of the semiconductor wafer. The dicing of the semiconductor wafer is performed with a commercially available dicing apparatus. This may be cutting with a blade or division by laser processing. The dicing tape has a base film and an adhesive layer formed on the surface of the base film. A commercially available dicing tape can be applied to the dicing tape in which the adhesive layer is applied to the base film.

  The alignment between the semiconductor chip and the circuit board is preferably such that the alignment mark formed on the circuit surface of the chip can be identified through the adhesive layer of the adhesive film for processing a semiconductor wafer attached to the circuit surface of the semiconductor chip. The alignment mark can be identified by a chip recognition device mounted on a normal flip chip bonder. This recognition device is usually composed of a halogen light source having a halogen lamp, a light guide, an irradiation device, and a CCD camera. The image captured by the CCD camera is checked for consistency with the image pattern for registration registered in advance by the image processing apparatus, and the alignment operation is performed.

  When a part of the adhesive layer and separation layer of the adhesive film for semiconductor wafer processing of the present invention is used and the semiconductor chip and the circuit board are connected, the adhesive layer and part of the separation layer are cured by heating and pressing. To do. If the curing reaction rate at this time is low, the connection after heating is not maintained, which is not preferable. The curing reaction rate is desirably 80% or more. If the adhesive is such that the curing reaction rate becomes 80% or more when heated at 180 ° C. for 20 seconds, the cured state can maintain the electrical connection after connection in the range of connection conditions by normal heating and pressing. Therefore, the reactivity of the material can be determined using the reaction rate at 180 ° C. for 20 seconds as an index. In the present invention, it is more preferable to perform heat treatment so that the curing reaction rate is 90% or more.

  The viscosity of the separation layer and the adhesive layer in the adhesive film for semiconductor wafer processing of the present invention at 20 ° C. or more and less than 40 ° C. before heating and curing is preferably 150,000 Pa · s or less. More preferably, the viscosity is in the range of 500 Pa · s to 150,000 Pa · s. When the viscosity is greater than 150,000 Pa · s, the semiconductor chip is temporarily fixed to the mounting position on the circuit board after the semiconductor chip and the circuit board are aligned, and the semiconductor chip is unstablely fixed. This is not preferable because parallelism with the pressing tool is lost and uniform application of the applied pressure is not possible. A viscosity of less than 500 Pa · s is not preferable because the resin flows when the semiconductor chip is temporarily fixed, and the target thickness cannot be maintained.

  It is preferable that the viscosity at 30 ° C. before heat curing of the adhesive layer is larger than the viscosity at 30 ° C. before heat curing of the separation layer.

The viscosity of the separation layer and the adhesive layer before heat curing can be measured using a commercially available dynamic viscoelasticity measuring apparatus, and the measurement can be performed fully automatically. Specifically, when a sample is sandwiched between two parallel plates in a thermostat heated to a predetermined temperature and a minute sinusoidal twist distortion is applied to one plate, the stress generated on the other plate The elastic modulus and viscosity are calculated from the strain. Generally, the measurement frequency is 0.5 to 10 Hz, and the polymer material behaves as a viscoelastic body, so that a storage elastic modulus G ′ derived from an elastic component and a loss elastic modulus G ″ derived from a viscous component are obtained. From the two values, the complex elastic modulus G ^* is given by the equation shown in the following formula 1. Further, when the viscosity is η (Pa · s), the measurement frequency is f (Hz), and the complex elastic modulus G ^* (Pa), The viscosity is given by the formula shown in the following formula 2.

  Hereinafter, the present invention will be described in detail by way of examples.

Example 1
Liquid epoxy resin containing 30 parts by weight of phenoxy resin (InChem, PKHC), 20 parts by weight of epoxy resin (DIC-made, N-672-EXP) as a three-dimensional crosslinkable resin, and microcapsule type latent curing agent Using 50 parts by weight (manufactured by Asahi Kasei Co., Ltd., HX-3941HP) and a silane coupling agent (manufactured by Dow Corning Toray, SH6040), it was dissolved in a mixed solvent of toluene and ethyl acetate to obtain a varnish. Furthermore, this varnish was pulverized and subjected to a 5 μm classification treatment to remove large particle diameters. Cordierite particles having an average particle diameter of 1 μm (2MgO · 2Al ₂ O ₃ · 5SiO ₂ , specific gravity 2.4, linear expansion coefficient) 1.5 × 10 ⁻⁶ / ° C., refractive index 1.57) 100 parts by weight were mixed, stirred and dispersed to obtain an adhesive layer forming resin composition varnish. After applying this varnish on a separator film (PET film) whose surface was subjected to a release treatment using a roll coater, the varnish was dried in an oven at 70 ° C. for 10 minutes to form an adhesive layer having a thickness of 50 μm on the separator. Formed.

  The viscosity of the obtained adhesive layer film was measured by the following method. First, the adhesive layer film was laminated to prepare a sample having a thickness of 500 μm. Using a viscoelasticity measuring device ARES manufactured by Rheometrics Scientific F.E. Co., Ltd., this was sandwiched between 8 mm diameter parallel plates at a frequency of 10 Hz in the process of raising the temperature from 25 ° C. to 250 ° C. at 10 ° C./min. The viscosity behavior of was measured. As a result, the viscosity at 30 ° C. was 120,000 Pa · s.

  On the other hand, it contains 30 parts by weight of phenoxy resin (manufactured by InChem, PKHC), 20 parts by weight of epoxy resin (manufactured by DIC Corporation, N-672-EXP) as a three-dimensional crosslinkable resin, and contains a microcapsule type latent curing agent. Liquid epoxy resin (Asahi Kasei Co., Ltd., HX-3941HP) 50 parts by weight and silane coupling agent (Toray Dow Corning, SH6040) are dissolved in a mixed solvent of toluene and ethyl acetate to form a separation layer resin. A varnish of the composition was obtained. After applying this varnish on a base film (PET film) using a roll coater, it was dried in an oven at 70 ° C. for 10 minutes to form a separation layer having a thickness of 3 μm on the separator. As a result of measuring the viscosity of the obtained separation layer film using a viscoelasticity measuring apparatus in the same manner as the adhesive layer, the viscosity at 30 ° C. was 22000 Pa · s.

  Next, the adhesive layer and the separation layer are bonded together through a laminator and cut out to approximately the same outer shape and size as the semiconductor wafer (8 inches), and then the release-treated PET on the adhesive layer side is peeled off and separated onto one side. The adhesive layer side was bonded on the carrier tape on which the mold layer was formed, and an adhesive film for processing a semiconductor wafer having a laminated structure of carrier tape / release layer / adhesive layer / separation layer / base film was obtained.

  Using a tape laminator, the adhesive layer after peeling the carrier tape from the obtained adhesive film for processing semiconductor wafers is laminated on a semiconductor wafer with an oxide film at 80 ° C. A semiconductor wafer with an adhesive film for processing was obtained.

  Furthermore, when the base film was peeled off from the semiconductor wafer, the separating layer could be peeled off by cohesive failure. As a result of measuring the thickness of the resin remaining on the base film with a micrometer, the thickness was a maximum of 3 μm.

(Example 2)
15 parts by weight of epoxy resin (manufactured by DIC Corporation, N-672-EXP) as a three-dimensional crosslinkable resin, and phenol aralkyl resin (manufactured by Mitsui Chemicals, XLC-LL) as a curing agent that reacts with the three-dimensional crosslinkable resin Parts by weight, acrylic rubber (butyl acrylate 40 parts ethyl acrylate 30 parts acrylonitrile 30 parts glycidyl methacrylate 3 parts copolymer, molecular weight: 850,000) liquid epoxy resin containing a microcapsule type latent curing agent (Asahi Kasei) 50 parts by weight of HX-3941HP (manufactured by Co., Ltd.) and a silane coupling agent (manufactured by Dow Corning Toray, SH6040) were dissolved in a mixed solvent of toluene and ethyl acetate to obtain a varnish. Furthermore, this varnish was pulverized and subjected to a 5 μm classification treatment to remove large particle diameters. Cordierite particles having an average particle diameter of 1 μm (2MgO · 2Al ₂ O ₃ · 5SiO ₂ , specific gravity 2.4, linear expansion coefficient) 1.5 × 10 ⁻⁶ / ° C., refractive index 1.57) 100 parts by weight were mixed, stirred and dispersed to obtain a varnish of the resin composition for forming an adhesive layer. After applying this varnish on a separator film (PET film) whose surface was subjected to a release treatment using a roll coater, the varnish was dried in an oven at 70 ° C. for 10 minutes to form an adhesive layer having a thickness of 50 μm on the separator. Formed.

  When the viscosity behavior of the adhesive layer was measured in the same manner as in Example 1, the viscosity at 30 ° C. was 95,000 Pa · s.

  On the other hand, 15 parts by weight of an epoxy resin (manufactured by DIC Corporation, N-672-EXP) as a three-dimensional crosslinkable resin, and a phenol aralkyl resin (manufactured by Mitsui Chemicals, XLC-) as a curing agent that reacts with the three-dimensional crosslinkable resin. LL) 15 parts by weight, acrylic rubber (butyl acrylate 40 parts ethyl acrylate 30 parts acrylonitrile 30 parts glycidyl methacrylate 3 parts copolymer, molecular weight: 850,000) 20 parts by weight, liquid epoxy containing microcapsule type latent curing agent 50 parts by weight of resin (manufactured by Asahi Kasei Co., Ltd., HX-3941HP) and a silane coupling agent (manufactured by Dow Corning Toray, SH6040) are dissolved in a mixed solvent of toluene and ethyl acetate, and a resin composition for forming a separation layer The varnish was obtained. After applying this varnish on a base film (PET film) using a roll coater, it was dried in an oven at 70 ° C. for 10 minutes to form a separation layer having a thickness of 3 μm on the separator. As a result of measuring the viscosity of the obtained separation layer film using a viscoelasticity measuring apparatus in the same manner as the adhesive layer, the viscosity at 30 ° C. was 18000 Pa · s.

  Next, the adhesive layer and the separation layer are bonded together through a laminator, cut out to approximately the same outer shape and size as the semiconductor wafer (8 inches), and then the release-treated PET on the adhesive layer side is peeled off and separated onto one side. The adhesive layer side was bonded onto the carrier tape on which the shape layer was formed, and an adhesive film for processing a semiconductor wafer having a laminated structure of carrier tape / release layer / adhesive layer / separation layer / base film was obtained.

  Using a tape laminator, the adhesive layer after peeling the carrier tape from the obtained adhesive film for processing semiconductor wafers is laminated on a semiconductor wafer with an oxide film at 80 ° C. A semiconductor wafer with an adhesive film for processing was obtained.

  Furthermore, when the base film was peeled off from the semiconductor wafer, the separating layer could be peeled off by cohesive failure. As a result of measuring the thickness of the resin remaining on the base film with a micrometer, the thickness was a maximum of 3 μm.

(Comparative Example 1)
In the same manner as in Example 1, a varnish of a resin composition for forming an adhesive layer was obtained. After applying this varnish on a separator film (PET film) having a release treatment applied to the surface using a roll coater, the varnish was dried in an oven at 70 ° C. for 10 minutes to form an adhesive layer having a thickness of 50 μm on the separator. Formed.

  Next, the same varnish as described above was applied on a base film (PET film) using a roll coater, and then dried in an oven at 70 ° C. for 10 minutes to form a separation layer having a thickness of 3 μm.

  Next, the adhesive layer and the separation layer are bonded together using a laminator, the separator on the adhesive layer side is peeled off, and the adhesive layer is bonded onto the carrier tape having a release layer formed on one side. An adhesive film for processing a semiconductor wafer having a laminated structure of / release layer / adhesive layer / separation layer / base film was obtained.

  After laminating the adhesive layer after peeling the carrier tape from the obtained adhesive film for semiconductor wafer processing using a tape laminator, the surface of the wafer was laminated to an oxide film semiconductor wafer at 80 ° C., and then the outer periphery of the wafer using a cutter knife When cut out almost identically, burrs and cutting chips were generated. Subsequently, when the base film was peeled off from the semiconductor wafer, a part was cohesive failure and a part was peeled off at the wafer interface. The maximum thickness of the resin remaining on the base film was 53 μm.

(Comparative Example 2)
In the same manner as in Example 2, a varnish of a resin composition for forming an adhesive layer was obtained. After applying this varnish on a separator film (PET film) whose surface was subjected to a release treatment using a roll coater, the varnish was dried in an oven at 70 ° C. for 10 minutes to form an adhesive layer having a thickness of 50 μm on the separator. Formed.

  Next, the same varnish as described above was applied on a base film (PET film) using a roll coater, and then dried in an oven at 70 ° C. for 10 minutes to form a separation layer having a thickness of 3 μm.

  Next, the adhesive layer and the separation layer are bonded together using a laminator, the separator on the adhesive layer side is peeled off, and the adhesive layer is bonded onto the carrier tape having a release layer formed on one side. An adhesive film for processing a semiconductor wafer having a laminated structure of / release layer / adhesive layer / separation layer / base film was obtained.

  After laminating the adhesive layer after peeling the carrier tape from the obtained adhesive film for semiconductor wafer processing using a tape laminator, the surface of the wafer was laminated to an oxide film semiconductor wafer at 80 ° C., and then the outer periphery of the wafer using a cutter knife Accordingly, the remaining adhesive film for processing was stuck to the periphery of the sticking table and could not be recovered. Subsequently, when the base film was peeled off from the semiconductor wafer, a part was cohesive failure and a part was peeled off at the wafer interface. The maximum thickness of the resin remaining on the base film was 53 μm.

  According to the adhesive film for processing a semiconductor wafer of Examples 1 and 2, the thickness of the resin on the base film that has been peeled off can be secured without sticking burrs or cutting chips after being attached to the semiconductor wafer. Is equivalent to the thickness of the separation layer, it was confirmed that an adhesive layer sufficient for flip chip connection could be left on the semiconductor wafer. Therefore, the adhesive film for processing a semiconductor wafer of Examples 1 and 2 is useful as an adhesive film for processing a semiconductor wafer that enables uniform and flat back grind processing in a state of being attached to the semiconductor wafer, and can perform flip chip mounting. I understood that.

  On the other hand, the adhesive films for processing semiconductor wafers of Comparative Examples 1 and 2 cause burrs when they are cut into a semiconductor wafer shape, or adhere to the laminating apparatus, and peel off the base film. At this time, since the adhesive is peeled off from the surface of the semiconductor wafer, it is difficult to use it for semiconductor wafer processing and flip chip mounting.

  ADVANTAGE OF THE INVENTION According to this invention, while solving the problem in a back grinding process, the base film can be easily peeled off from an adhesive layer, and the adhesive film for semiconductor processing which does not generate | occur | produce the performance deterioration of an adhesive layer easily is provided. Can do. Such an adhesive film for processing a semiconductor wafer is applied to a semiconductor wafer before the back grinding process, back grinded, and even if the base film is peeled off after dicing, the adhesive is not peeled off from the surface of the semiconductor wafer. Since a semiconductor chip with an adhesive can be obtained later and can be used for flip chip connection, it is possible to reduce the substrate attaching step of the adhesive film for chip connection, which helps shorten the manufacturing process of the semiconductor device.

  DESCRIPTION OF SYMBOLS 10 ... Semiconductor wafer, 10a ... Projection electrode, 1 ... Base film, 2 ... Separation layer, 3 ... Adhesive layer, 3a ... Adhesive layer, 4 ... Release layer, 5 ... Carrier film, 12 ... Back grinder, 14 Dicing frame 14a Lower edge 16 Dicing tape 16a Base film 16b Adhesive layer 26 Adhesive tape 30 Semiconductor chip 40 Circuit board 42 Circuit electrode 50 Semiconductor device R1 ... Laminate, F1 ... Adhesive film for semiconductor wafer processing, F1a ... Tape for semiconductor wafer processing, S1 ... Main surface, S2 ... Back surface.

Claims (4)

An adhesive film used for processing a semiconductor wafer, having a release layer, an adhesive layer, a separation layer and a base film in this order on a carrier tape,
The adhesive layer, the separation layer, and the base film are formed in a wafer shape that is substantially the same size as the semiconductor wafer to be processed ,
The adhesive layer includes at least a thermosetting resin, a high molecular weight component, and a compound for starting a crosslinking reaction of the thermosetting resin, and a filler,
The separation layer comprises a resin composition comprising at least a thermosetting resin, a high molecular weight component, and a compound for promoting a crosslinking reaction of the thermosetting resin;
The cohesive force of the separation layer is smaller than the cohesive force of the adhesive layer;
An adhesive film for processing a semiconductor wafer, wherein a surface of the adhesive layer opposite to the separation layer is a surface attached to a semiconductor wafer. When the adhesive layer is laminated on the protruding electrode side of the semiconductor wafer provided with protruding electrodes, the adhesive layer of the adhesive film for processing a semiconductor wafer from which the carrier tape and the release layer are removed. The thickness of the adhesive layer is formed to be larger than the height of the protruding electrode, and the height of the circuit electrode of the circuit board to which the semiconductor chip obtained from the semiconductor wafer is flip-chip connected and the height of the protruding electrode The adhesive film for processing a semiconductor wafer according to claim 1, wherein the adhesive film is formed with a thickness larger than the total of the above. The said separation layer and the said adhesive bond layer have thermosetting, and the viscosity in 20 degreeC or more and less than 40 degreeC before heat-curing is 150,000 Pa.s or less, The Claim 1 or 2 characterized by the above-mentioned. The adhesive film for semiconductor wafer processing as described. Preparing a semiconductor wafer processing adhesive film according to any one of claims 1 to 3,
The adhesive layer having the surface opposite to the separation layer exposed by peeling off the carrier tape and the release layer of the adhesive film for processing a semiconductor wafer is attached to the circuit surface of the semiconductor wafer having a circuit surface. Process,
Grinding the opposite side of the semiconductor wafer from the circuit surface;
The ground semiconductor wafer is diced together with the adhesive layer, the separation layer, and the base film, and then a part of the separation layer and the base film are removed or the ground semiconductor wafer. After removing a part of the separation layer and the base film, the adhesive layer and a part of the separation layer are diced together to separate the adhesive layer and a part of the separation layer. Obtaining a semiconductor chip having
Connecting the semiconductor chip and the circuit board via the separated adhesive layer to obtain a semiconductor device;
A method for manufacturing a semiconductor device, comprising:

Images