JP2010278198A - Wafer processing sheet - Google Patents

Abstract

Provided is a wafer processing sheet in which an adhesive layer of an adhesive sheet does not adhere to the upper surface of a chip and does not contaminate the chip in an expanding process.
A wafer processing sheet 100 includes an adhesive sheet 106 in which an adhesive layer 104 is laminated on a base material 102, and a ring-shaped wafer contamination-preventing pressure-sensitive adhesive sheet 112. The adhesive for the adhesive sheet 106 is provided. A wafer processing sheet 100 in which the wafer contamination preventing adhesive sheet 112 is laminated on a layer 104, the wafer contamination preventing adhesive sheet 112 having a size that can be fixed to a ring frame 300, and the wafer contamination The prevention adhesive sheet 112 has an inner diameter 0 to 20 mm smaller than the diameter of the wafer 200.
[Selection] Figure 1

Description

  The present invention relates to a wafer processing sheet. More specifically, the present invention comprises an adhesive sheet in which an adhesive layer is laminated on a base material and a ring-shaped adhesive sheet for preventing contamination of a wafer, and for preventing contamination of the wafer on the adhesive layer of the adhesive sheet. The present invention relates to a wafer processing sheet on which an adhesive sheet is laminated.

  In the process of manufacturing a semiconductor device, a wafer on which a predetermined circuit is formed is cut and separated into a plurality of chips. Further, in the die bonding step subsequent to the cutting and separating step, the chip and the wiring substrate are die-bonded.

  In the cutting and separating step, conventionally, a semiconductor wafer has been cut by a rotating blade called a dicing blade that rotates at a high speed. As the wafer processing sheet used at this time, a circular dicing tape having a thermosetting adhesive layer on a substrate, and a ring-shaped adhesive sticking prevention adhesive tape having an adhesive layer on the substrate, There is known a wafer processing sheet in which a base material of the adhesive tape for preventing adhesion of adhesive is laminated on an adhesive layer of the dicing tape (see Patent Document 1, etc.). The adhesive layer of the dicing tape has the capability of fixing the wafer during dicing and capable of die-bonding the chip and the wiring board during die bonding.

  On the other hand, as an alternative to the above dicing method, a prior dicing method (abbreviated as “DBG”) and a stealth dicing method have been tried. In these methods, by expanding the wafer processing sheet, the adhesive layer of the adhesive sheet is cleaved according to the semiconductor chip to obtain a plurality of individual semiconductor chips with the adhesive layer (Patent Document 2, etc.) reference).

JP-A-8-213349 JP 2005-19962 A

  By the way, when the wafer processing sheet is used in the expanding process in the tip dicing method or the stealth dicing method, the adhesive layer exposed around the wafer is cracked, or pieces of the broken adhesive layer are scattered, There was a problem of adhering to the upper surface of the chip.

In particular, when the adhesive layer constituting the adhesive sheet of the wafer processing sheet is an inflexible adhesive so that it can be easily cleaved by the expand, the above problem is remarkable.
Accordingly, an object of the present invention is to provide a wafer processing sheet in which the adhesive layer of the adhesive sheet does not adhere to the upper surface of the chip and does not contaminate the chip in the expanding step.

The present inventors have found that the above problem can be solved by using a wafer contamination-preventing pressure-sensitive adhesive tape having a specific inner diameter.
That is, the wafer processing tape according to the present invention comprises an adhesive sheet in which an adhesive layer is laminated on a base material, and a ring-shaped wafer contamination-preventing pressure-sensitive adhesive sheet. A wafer processing sheet in which a wafer contamination prevention adhesive sheet is laminated, the wafer contamination prevention adhesive sheet having a size that can be fixed to a ring frame, and the inner diameter of the wafer contamination prevention adhesive sheet is a wafer It is characterized by being 0 to 20 mm smaller than the diameter.

The diameter of the wafer is preferably 100 to 450 mm.
The wafer-bonded wafer processing sheet according to the present invention comprises an adhesive sheet in which an adhesive layer is laminated on a substrate, and a ring-shaped wafer contamination-preventing pressure-sensitive adhesive sheet, on the adhesive layer of the adhesive sheet. A wafer processing sheet in which the entire back surface of the wafer is attached to the wafer processing sheet laminated with the wafer contamination prevention adhesive sheet, and the wafer contamination prevention adhesive sheet is attached to the ring frame. It has a size that can be fixed, and the inner diameter of the wafer contamination-preventing pressure-sensitive adhesive sheet is 0 to 20 mm smaller than the diameter of the wafer.

  A method for manufacturing a semiconductor device according to the present invention is a method for manufacturing a semiconductor device, comprising the steps of pasting a wafer on a wafer processing sheet, expanding the wafer processing sheet, and cleaving the adhesive layer. The processing sheet is composed of an adhesive sheet in which an adhesive layer is laminated on a base material and a ring-shaped wafer contamination-preventing adhesive sheet, and the wafer contamination-preventing adhesive sheet is formed on the adhesive layer of the adhesive sheet. A wafer processing sheet laminated, the wafer contamination preventing pressure-sensitive adhesive sheet having a size that can be fixed to a ring frame, and the wafer contamination preventing pressure-sensitive adhesive sheet having an inner diameter of 0 to 20 mm smaller than the diameter of the wafer. It is a sheet for wafer processing.

  According to the wafer processing sheet of the present invention, it is possible to prevent the adhesive layer of the adhesive sheet from adhering to the upper surface of the chip and contaminating the chip in the cutting process of the adhesive layer.

FIG. 1 is a view for explaining a wafer processing tape according to the present invention. FIG. 2 is a diagram showing a ring frame. FIG. 3 is a view for explaining a conventional wafer processing tape.

Hereinafter, the present invention will be specifically described.
FIG. 1 is a cross-sectional view of a wafer processing sheet according to the present invention. A wafer processing sheet 100 according to the present invention is a wafer processing sheet having a pre-cut configuration, a circular adhesive sheet 106 in which an adhesive layer 104 is laminated on a base material 102, and an adhesive layer on the base material 108. 110 is a ring-shaped adhesive sheet 112 for preventing contamination of a wafer. Further, the adhesive sheet 106 and the wafer contamination preventing adhesive sheet 112 are adhered to each other by the adhesive layer 104 of the adhesive sheet 106 and the base material 108 of the wafer contamination preventing adhesive sheet 112. The wafer processing sheet 100 has a function that can be used for wafer cleaving (when used in a stealth dicing method described later) and die bonding. In FIG. 1, “the manner in which the wafer 200 is affixed in the semiconductor wafer affixing step and the position where the ring frame 300 is affixed are shown by dotted lines, which will be described later.

  First, the adhesive sheet 106 constituting the wafer processing tape 100 according to the present invention will be described. The adhesive layer 104 of the adhesive sheet 106 is detachably laminated on the base material 102. Thereby, when the chip is picked up in the pick-up process, the separated adhesive layer 104 remains fixed on the back surface of the chip and functions as a die bond layer for an adherend such as a substrate. Further, the adhesive layer 104 can be cleaved in the expanding step. Specific examples of the dicing tape 106 include dicing tapes described in JP-A-60-35531 and JP-A-2-32181.

  A resin film is used for the base material 102, and a resin film excellent in expandability is preferably used. The surface tension of the substrate 102 is preferably 40 mN / m or less, more preferably 35 mN / m or less. When the surface tension is in the above range, the peelability from the adhesive layer is improved, and the chip can be easily picked up with the adhesive layer on the back surface. As such a base material, a material having a low surface tension may be used originally, or a material having a surface tension lowered by applying a release treatment by applying a silicone resin or the like to the surface may be used.

  The thickness of the base material 102 is usually in the range of 10 to 500 μm, preferably 15 to 300 μm, particularly preferably 20 to 250 μm. If the thickness is less than the above range, the substrate may tear during expansion. Moreover, when thickness exceeds the said range, it may be too hard to expand a base material.

  The adhesive layer 104 has adhesiveness at room temperature, or has adhesiveness by heating at about 40 ° C. Moreover, since it has thermosetting property, the chip and the wiring board can be firmly bonded and fixed by heat curing in the die bonding step. For the adhesive layer 104, an adhesive that is easy to cleave at a low temperature is suitably used when expanding at a low temperature (about 0 ° C.). Specifically, the components constituting the adhesive layer 104 are a thermosetting resin, a binder resin, a curing agent, and a curing accelerator added as necessary. Examples of the thermosetting resin include resins such as epoxy, phenoxy, phenol, resorcinol, urea, melamine, furan, unsaturated polyester, and silicone. Examples of the binder resin include acrylic, polyester, polyvinyl ether, urethane, and polyamide. And other resins.

The adhesive layer 104 may be made of a B-stage (semi-cured) thermosetting adhesive component.
As a component constituting the adhesive layer 104, an ultraviolet curable component may be further blended. When such an adhesive layer 104 is irradiated with ultraviolet rays, the peelability from the base material 102 is improved, so that a chip having an adhesive layer on the back surface can be easily picked up at the time of picking up.

The thickness of the adhesive layer 104 is usually 1 to 200 μm, preferably 2 to 100 μm, and particularly preferably 3 to 50 μm.
Next, the wafer contamination preventing pressure-sensitive adhesive sheet 112 constituting the wafer processing sheet 100 according to the present invention will be described. The wafer contamination-preventing pressure-sensitive adhesive sheet 112 is ring-shaped, has a cavity (internal opening), and has a size that can be fixed to the ring frame 300 as shown in FIG. Specifically, the outer diameter of the wafer contamination preventing adhesive sheet 112 is larger than the inner diameter R ₃₀₀ of the ring frame 300. In general, the inner diameter R ₁₁₂ of the wafer contamination preventing adhesive sheet 112 is smaller than R ₃₀₀ . The ring frame 300 is usually a molded body of metal or plastic. As shown in FIG. 1, the wafer contamination preventing adhesive tape 112 is composed of a base material 108 and an adhesive layer 110, and a ring frame 300 is adhered to the adhesive layer 110.

  Although it does not restrict | limit especially as the base material 108 which comprises the adhesive tape 112 for wafer contamination prevention, For example, a polyethylene film, a polypropylene film, an ethylene-vinyl acetate copolymer film, an ethylene- (meth) acrylic acid copolymer film, ethylene -Polyolefin films such as (meth) acrylic acid ester copolymer films and ionomer resin films, polyvinyl chloride films, polyethylene terephthalate films, and the like. Among these, a polyvinyl chloride film is preferable in consideration of expandability.

The thickness of the base material 108 is appropriately selected in consideration of the thickness of the wafer contamination preventing adhesive sheet 112 and the thickness of the adhesive layer 110.
Although it does not restrict | limit especially as an adhesive which forms the adhesive layer 110, For example, it is preferable to consist of an acrylic adhesive, a rubber-type adhesive, or a silicone adhesive. Among these, an acrylic pressure-sensitive adhesive is preferable in consideration of removability from the ring frame. Moreover, the adhesive which forms the adhesive layer 110 may be used independently, or 2 or more types may be mixed and used for it.

  The thickness of the pressure-sensitive adhesive layer 110 is preferably 2 to 20 μm, more preferably 3 to 15 μm, and still more preferably 4 to 10 μm. When it is less than 2 μm, sufficient adhesion may not be exhibited. When the thickness exceeds 20 μm, an adhesive residue may remain on the ring frame when it is peeled from the ring frame, which may contaminate the ring frame.

  The thickness of the wafer contamination preventing adhesive sheet 112 is preferably 7 to 220 μm, more preferably 13 to 180 μm, and still more preferably 24 to 120 μm. If it is less than 7 μm, it may be difficult to handle because it is thin. When it exceeds 220 μm, when the wafer 200 is affixed to the wafer processing sheet 100, there is a step corresponding to the thickness of the adhesive sheet 112 for preventing wafer contamination between the adhesive layer 104 of the adhesive sheet 106 and the wafer 200. The wafer may not be kept smooth.

The wafer processing sheet according to the present invention, the inside diameter R ₁₁₂ of the pressure-sensitive adhesive sheet for preventing wafer contamination is less 0~20mm than the diameter R ₂₀₀ of the wafer. That is, R ₁₁₂ is equal to R ₂₀₀ or R ₁₁₂ is smaller than R ₂₀₀ by a length of more than 0 mm and not more than 20 mm. R ₁₁₂ is preferably smaller than R _{200 by} less than 0 mm and not more than 20 mm, more preferably by 1 to 15 mm, and even more preferably by 2 to 10 mm. Thereby, according to the wafer processing sheet according to the present invention, in the cleaving step of the adhesive layer, since there is no portion where the adhesive layer of the adhesive sheet is exposed, small pieces of the adhesive layer of the adhesive sheet are scattered. Therefore, it is possible to suppress adhesion to the upper surface of the chip. In this way, contamination of the chip is suppressed.

The diameter R ₂₀₀ of the wafer is preferably 100 to 450 mm. More specifically, the diameter _{R 200, 100mm, 150mm, 200mm} , 300mm, 400mm, a wafer of 450mm is used.

For example, when processing a wafer having a diameter R ₂₀₀ of 200 mm, the inner diameter R ₁₁₂ of the wafer contamination preventing adhesive sheet 100 of the wafer processing sheet 100 according to the present invention is 180 to ₂₀₀ mm.

  A wafer processing sheet 100 according to the present invention shown in FIG. 1 is produced, for example, as follows. The adhesive sheet before the predetermined shape and the pressure-sensitive adhesive sheet for preventing contamination of the wafer are each produced based on a known coating method. A release film is laminated on the surface of the adhesive layer of the adhesive sheet and the surface of the adhesive layer of the pressure-sensitive adhesive sheet for preventing wafer contamination. First, the substrate and the pressure-sensitive adhesive layer are punched out while leaving the release film of the wafer contamination-preventing pressure-sensitive adhesive sheet to form an opening having a predetermined inner diameter. Next, the release film of the adhesive sheet is peeled off and attached so that the adhesive layer of the adhesive sheet and the base material surface of the pressure-sensitive adhesive sheet for preventing wafer contamination are combined. Further, the adhesive sheet and the wafer contamination preventing pressure-sensitive adhesive sheet are punched out while leaving the release film of the wafer contamination preventing pressure-sensitive adhesive sheet to form the outer edge of the wafer processing sheet. At this time, the wafer forming sheet is punched so that the circle forming the outer edge of the wafer processing sheet and the opening circle of the wafer contamination preventing pressure-sensitive adhesive sheet are concentric. Finally, it winds up with the some wafer processing sheet affixed on the peeling film, and stores and conveys. Further, in the production of the wafer processing sheet described above, the processing order and the like may be appropriately changed.

  The wafer processing sheet 100 of the present invention is used, for example, as follows in the process of manufacturing a semiconductor. In other words, the method for manufacturing a semiconductor device of the present invention includes the steps of attaching a wafer to the above-described wafer processing sheet, expanding the wafer processing sheet, and cleaving the adhesive layer. Specifically, the case where the tip dicing method is used and the case where the stealth dicing method is used will be described separately.

<Manufacturing Method of Semiconductor Device Using Stealth Dicing Method>
A manufacturing method of a semiconductor device using a stealth dicing method includes the following steps.
(1) A step of irradiating the wafer with a pulse laser having transparency with respect to the wafer along the division line to form a deteriorated layer along the division line inside the wafer;
(2) The process of sticking the semiconductor wafer in which the altered layer was formed on the adhesive bond layer of the adhesive sheet in the wafer processing sheet of the present invention,
(3) a step of expanding the adhesive sheet to which the wafer is affixed to divide the wafer and the adhesive layer; and (4) a state in which the divided adhesive layer is fixed and left on the back surface of the chip. , A step of peeling the chip from the base material of the adhesive sheet, and thermocompression bonding the chip to an adherend through the adhesive layer.

-(1) Altered layer formation step-
From the surface of the semiconductor wafer, a pulse laser having transparency to the wafer is irradiated to the wafer along the planned division line, and an altered layer is formed along the planned division line inside the wafer. This step is performed according to, for example, the descriptions in Japanese Patent Application Laid-Open Nos. 2003-338467 and 2005-223283.

-(2) Semiconductor wafer pasting process-
The wafer having the ring frame and the altered layer formed thereon is left standing on the laminating apparatus, and the adhesive layer of the wafer contamination preventing sheet in the wafer processing sheet of the present invention is in contact with the ring frame, and the wafer contamination preventing sheet is adhered. The sheet is stuck so that a part of the agent layer and the adhesive layer of the adhesive sheet are in contact with the back surface of the wafer. Next, the wafer is fixed by lightly pressing. It is preferable to attach the wafer processing sheet so that the circle formed by the inner diameter of the wafer contamination preventing sheet and the circle formed by the outer edge of the wafer are concentric. In this way, the wafer-bonded wafer processing sheet of the present invention in which the entire back surface of the wafer is bonded is obtained.
The (1) altered layer forming step and (2) the semiconductor wafer attaching step may be performed in the reverse order.

-(3) Expanding process-
The wafer processing sheet to which the wafer is attached is expanded using an expanding device. In this expanding step, the wafer and the adhesive layer are sufficiently separated into individual chips, and a chip in which the adhesive layer remains fixed is obtained. Here, in the wafer processing sheet of the present invention, the inner diameter R ₁₁₂ of the wafer contamination preventing adhesive sheet is 0 to ₂₀ mm smaller than the wafer diameter R ₂₀₀ . Thus, since the adhesive layer of the adhesive sheet is not exposed around the wafer, the adhesive layer hardly adheres to the upper surface of the chip when the adhesive layer is cleaved, and the contamination of the chip is suppressed.

  In the expanding step, the expansion rate of the adhesive sheet is usually 1 to 200 mm / second, preferably 10 to 150 mm / second, and the expansion amount (drawing amount) is usually 1 to 30 mm, preferably 2 to 20 mm. is there. If the expansion speed and the expansion amount are below the above ranges, it may be difficult to separate the wafer and the adhesive layer. Further, when the expansion speed and the expansion amount exceed the above ranges, the wafer processing sheet may come off the ring frame.

-(4) Pick-up mounting process-
In a state where the adhesive layer remains fixed on the back surface of the semiconductor chip, the chip is peeled off from the base material, and the chip is placed on the adherend via the adhesive layer. Here, the adherend is usually a die pad portion on an organic substrate or a lead frame, or another chip fixed in advance on a die pad portion on the organic substrate or the lead frame.

  The die pad portion or other chip is preferably heated before mounting the chip or immediately after mounting. The heating temperature is usually 80 to 200 ° C., preferably 100 to 180 ° C., the heating time is usually 0.1 seconds to 5 minutes, preferably 0.5 seconds to 3 minutes, and the chip mount pressure is Usually, it is 1 kPa to 600 MPa.

  In addition, after mounting a chip | tip on a die pad part or another chip | tip, you may heat further as needed. The heating conditions at this time are in the above heating temperature range, and the heating time is usually 1 to 180 minutes, preferably 10 to 120 minutes.

Alternatively, the chip may be temporarily bonded without performing the heat treatment after mounting, and the adhesive layer may be cured by utilizing heating in resin sealing that is normally performed in the manufacture of a semiconductor device.
By passing through such a process, an adhesive bond layer hardens | cures and a chip | tip and a die pad part or another chip | tip can be adhere | attached firmly. Further, since the adhesive layer is fluidized under die bonding conditions, the adhesive layer is sufficiently embedded in the unevenness of the die pad portion or other chips, and generation of voids can be prevented.

  After the chip is picked up, the wafer processing sheet is peeled off from the ring frame. However, the wafer processing sheet of the present invention is adhered to the ring frame via the wafer contamination prevention adhesive sheet, so that the adhesive is applied to the ring frame. Hard to remain.

<Method for Manufacturing Semiconductor Device Using First Dicing Method>
A method for manufacturing a semiconductor device using the prior dicing method includes the following steps.
(1) A groove having a depth smaller than the thickness of the wafer is formed from the surface of the semiconductor wafer (surface on which the circuit is formed on the semiconductor wafer), and the back surface of the wafer (surface on which the circuit is not formed on the semiconductor wafer) is ground. A step of dividing the wafer into semiconductor chips,
(2) A step of attaching the divided wafer composed of the chip group obtained in the step (2) on the adhesive layer of the adhesive sheet in the wafer processing sheet of the present invention,
(3) a step of dividing the adhesive layer by expanding the adhesive sheet to which the wafer is affixed; and (4) the chip in a state where the divided adhesive layer remains fixed on the back surface of the chip. Is peeled from the base material of the adhesive sheet, and the chip is thermocompression bonded to the adherend through the adhesive layer.

-(1) Dicing process-
Using a cutting means such as a dicing saw, a groove having a predetermined depth smaller than the wafer thickness is formed from the wafer surface along the cutting position of the semiconductor wafer forming a plurality of sections. Next, a conventionally known surface protection sheet is attached to the wafer surface, and the back surface of the wafer is ground and divided into semiconductor chips.

-(2) Bonding process of divided semiconductor wafers composed of semiconductor chip groups-
The wafer processing sheet of the present invention is fixed on a laminating apparatus by a ring frame, and the surface of the divided semiconductor wafer composed of the semiconductor chip group is not attached to the surface of the adhesive sheet in the wafer processing sheet. It is placed on the adhesive layer and lightly pressed to fix the wafer. It is preferable to attach the wafer processing sheet so that the circle formed by the inner diameter of the wafer contamination preventing sheet and the circle formed by the outer edge of the wafer are concentric. In this way, the wafer-bonded wafer processing sheet of the present invention in which the entire back surface of the wafer is bonded is obtained. Next, the surface protection sheet is peeled from the wafer.

-(3) Expanding process-
The wafer processing sheet to which the wafer is attached is expanded using an expanding device. In this expanding step, the wafer and the adhesive layer are sufficiently separated into individual chips, and a chip in which the adhesive layer remains fixed is obtained. Here, in the wafer processing sheet of the present invention, the inner diameter R ₁₁₂ of the wafer contamination preventing adhesive sheet is 0 to ₂₀ mm smaller than the wafer diameter R ₂₀₀ . Thus, since the adhesive layer of the adhesive sheet is not exposed around the wafer, the adhesive layer hardly adheres to the upper surface of the chip when the adhesive layer is cleaved, and the contamination of the chip is suppressed.

  In the expanding step, the expansion rate of the adhesive sheet is usually 1 to 200 mm / second, preferably 10 to 150 mm / second, and the expansion amount (drawing amount) is usually 1 to 30 mm, preferably 2 to 20 mm. is there. When the expansion speed and the expansion amount are below the above ranges, it may be difficult to separate the adhesive layer. Further, when the expansion speed and the expansion amount exceed the above ranges, the wafer processing sheet may come off the ring frame.

-(4) Pick-up mounting process-
In a state where the adhesive layer remains fixed on the back surface of the semiconductor chip, the chip is peeled off from the base material, and the chip is placed on the adherend via the adhesive layer. Here, the adherend is usually a die pad part on an organic substrate or a lead frame, or another chip fixed in advance on a die pad part on the organic substrate or the lead frame.

  The die pad portion or other chip is preferably heated before mounting the chip or immediately after mounting. The heating temperature is usually 80 to 200 ° C., preferably 100 to 180 ° C., the heating time is usually 0.1 seconds to 5 minutes, preferably 0.5 seconds to 3 minutes, and the chip mount pressure is Usually, it is 1 kPa to 600 MPa.

  In addition, after mounting a chip | tip on a die pad part or another chip | tip, you may heat further as needed. The heating conditions at this time are in the above heating temperature range, and the heating time is usually 1 to 180 minutes, preferably 10 to 120 minutes.

Alternatively, the chip may be temporarily bonded without performing the heat treatment after mounting, and the adhesive layer may be cured by utilizing heating in resin sealing that is normally performed in the manufacture of a semiconductor device.
By passing through such a process, an adhesive bond layer hardens | cures and a chip | tip and a die pad part or another chip | tip can be adhere | attached firmly. Further, since the adhesive layer is fluidized under die bonding conditions, the adhesive layer is sufficiently embedded in the unevenness of the die pad portion or other chips, and generation of voids can be prevented.

  After the chip is picked up, the wafer processing sheet is peeled off from the ring frame. However, the wafer processing sheet of the present invention is adhered to the ring frame via the wafer contamination prevention adhesive sheet, so that the adhesive is applied to the ring frame. Hard to remain.

  By the way, the wafer processing sheet according to the present invention may be composed of a circular adhesive sheet in which an adhesive layer is laminated on a base material and a wafer contamination-preventing adhesive sheet which is a ring-shaped double-sided adhesive sheet. . That is, the pressure-sensitive adhesive sheet for preventing wafer contamination is composed of a base material as a core, a laminating pressure-sensitive adhesive layer formed on one surface thereof, and a fixing pressure-sensitive adhesive layer formed on the other surface. It consists of a double-sided pressure-sensitive adhesive sheet. The adhesive layer for lamination is laminated with the adhesive layer of the adhesive sheet, and the adhesive layer for fixing is attached to the ring frame in the attaching process of the semiconductor wafer.

Examples of the core material of the double-sided pressure-sensitive adhesive sheet include the same materials as those of the base material 108. Among these, a polyvinyl chloride film is preferable in consideration of expandability.
The thickness of the core material is the same as the thickness of the base material 108.

  The pressure-sensitive adhesive layer for lamination and the pressure-sensitive adhesive layer for fixing of the double-sided pressure-sensitive adhesive sheet may be a layer made of the same pressure-sensitive adhesive or a layer made of different pressure-sensitive adhesives. The adhesive force between the fixing pressure-sensitive adhesive layer and the ring frame is appropriately selected so as to be smaller than the adhesive force between the adhesive layer and the laminating pressure-sensitive adhesive layer. Examples of such an adhesive include acrylic, rubber, and silicone adhesive. Among these, an acrylic pressure-sensitive adhesive is preferable in consideration of removability from the ring frame. The pressure-sensitive adhesive forming the fixing pressure-sensitive adhesive layer may be used alone or in combination of two or more. The same applies to the adhesive layer for lamination.

The thickness of the laminating pressure-sensitive adhesive layer and the fixing pressure-sensitive adhesive layer is the same as the thickness of the pressure-sensitive adhesive layer 110.
The thickness of the double-sided pressure-sensitive adhesive sheet is the same as the thickness of the wafer contamination-preventing pressure-sensitive adhesive sheet 112.

Even with a wafer processing sheet using a double-sided pressure-sensitive adhesive sheet as such a wafer-contamination-preventing pressure-sensitive adhesive sheet, the adhesive layer of the adhesive sheet does not adhere to the upper surface of the chip in the manufacturing process of the semiconductor device described above, and the chip is contaminated. It is hard to be done.
EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples.

[Example]
[Evaluation methods]
Using an expander (ME-300 series, manufactured by JCM Co., Ltd.), wafers (divided into chips) having a diameter of 150 mm, a diameter of 200 mm, and a diameter of 300 mm under the conditions of a temperature of 0 ° C., an expansion speed of 50 mm / second, and an expansion amount of 15 mm The wafer processing sheet with the attached wafer) was expanded and the adhesive layer was cleaved. After performing the expansion, it was visually confirmed whether or not the chip was contaminated by the scattering of the adhesive layer.

<Production of adhesive sheet>
Aromatic polyisocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd.) with respect to 100 parts by weight of acrylic pressure-sensitive adhesive (acrylic copolymer based on butyl acrylate, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., Coponil N-3327) 2 parts of Coronate L) and 50 parts of toluene were added to prepare an adhesive solution. The pressure-sensitive adhesive solution is applied onto a silicone-treated release film 1 (SP-PET3811 (S), manufactured by Lintec Corporation), dried in an oven at 100 ° C. for 1 minute, and a fixing pressure-sensitive adhesive having a thickness of 5 μm. A layer was obtained.

  Aromatic polyisocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd., Coronate L) is added to 100 parts of acrylic adhesive (acrylic copolymer based on butyl acrylate, manufactured by Soken Chemical Co., Ltd., SK Dyne 1811L). 3 parts and 50 parts of toluene were added to prepare an adhesive solution. The pressure-sensitive adhesive solution is applied onto a silicone-treated release film 2 (SP-PET3811 (S), manufactured by Lintec Corporation), dried in an oven at 100 ° C. for 1 minute, and a pressure-sensitive adhesive for lamination having a thickness of 5 μm. A layer was obtained.

The fixing pressure-sensitive adhesive layer was bonded to a base film (50 μm PVC, manufactured by Okamoto Co., Ltd., PVC50 OSGP42B) and transferred onto the base film. Subsequently, the pressure-sensitive adhesive layer for lamination was bonded and transferred to the other surface of the base film to obtain a double-sided pressure-sensitive adhesive sheet.
In addition, the said adhesive sheet comprises the adhesive sheet for wafer contamination prevention in the wafer processing sheet.

<Preparation of adhesive sheet>
First, an adhesive composition having the following composition was prepared. In addition, a numerical value shows the weight part of solid content conversion. The adhesive composition 1 was applied to a silicone-treated release film (SP-PET 381031 manufactured by Lintec Corporation) to a thickness of 30 μm and dried in an oven at 100 ° C. for 1 minute to obtain an adhesive layer It was. Next, the adhesive layer was bonded to a base material (polyethylene film, thickness 100 μm, surface tension 33 mN / m) and transferred onto the base material to obtain an adhesive sheet.

In addition, the said adhesive sheet comprises an adhesive sheet in the sheet | seat for wafer processing.
(A) Acrylic copolymer: Acrylic copolymer based on butyl acrylate (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., N-2359-6) 10 parts by weight (B) Epoxy resin: Acrylic rubber fine particle dispersed bisphenol A type 32 parts by weight of liquid epoxy resin (manufactured by Nippon Shokubai Co., Ltd., BPA328) (C) Thermosetting agent: novolac type phenolic resin (Showa High Polymer Co., Ltd., Shonor BRG556)
(D) Curing accelerator: Imidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., Curesol 2PHZ) 2 parts by weight (E-1) Coupling agent: Silane coupling agent (Mitsubishi Chemical Co., Ltd., MKC silicate MSEP2) 0.9 weight Part (E-2) Coupling agent: Silane coupling agent (manufactured by Toray Dow Corning Silicone Co., Ltd., SZ6083) 0.3 part by weight (F) Inorganic filler: Silica filler (manufactured by Admatechs Co., Ltd., Admafine SC2050) 20 Parts by weight (G) flexible component: polyester resin (Byron 220, manufactured by Toyobo Co., Ltd.) 30 parts by weight (H) energy ray curable component: dicyclopentadiene skeleton-containing acrylate (manufactured by Nippon Kayaku Co., Ltd., Kayrad R684) 9 parts by weight Part (I) Photoinitiator: Irgacure 184 (Ciba Specialty Chemicals Co., Ltd.) 0.5 parts by weight

[Example 1]
The pressure-sensitive adhesive sheet is die-cut to an inner diameter of 148 mm, and while peeling the release film 2 of the pressure-sensitive adhesive sheet and the release film of the adhesive sheet, the pressure-sensitive adhesive layer for laminating the pressure-sensitive adhesive sheet is in contact with the adhesive layer of the adhesive sheet. Laminated. The laminated sheets were punched to an outer diameter of 220 mm so as to be concentric with the punched circle. Before sticking on a wafer, the release film 1 of the adhesive sheet was peeled off. In this manner, a wafer processing sheet for use with a wafer having a diameter of 150 mm, which was precut as shown in FIG. 1, was prepared.

  A silicon wafer having a diameter of 150 mm and a thickness of 100 μm was irradiated with a pulse laser having a wavelength of 1064 nm, and a deteriorated layer was formed inside the wafer along a planned division line of 5 mm × 5 mm.

Using a tape mounter (RAD2500, manufactured by Lintec Co., Ltd.), the silicon wafer and the ring frame (inner diameter 195 mm) were attached to the wafer processing sheet prepared above so as to be concentric. Ultraviolet rays were irradiated (215 mW / cm ² , 170 mJ / cm ² ) from the base material surface of the adhesive sheet using an ultraviolet ray irradiation device (RAD2000, manufactured by Lintec Corporation).

  Thereafter, the wafer was divided and the adhesive layer was cleaved using an expanding apparatus. After performing the expansion, it was visually confirmed whether or not the chip was contaminated by the scattering of the adhesive layer.

[Example 2]
The pressure-sensitive adhesive sheet is die-cut to an inner diameter of 192 mm, and the pressure-sensitive adhesive layer for the pressure-sensitive adhesive sheet and the adhesive layer of the adhesive sheet are in contact with each other while peeling the release film 2 of the pressure-sensitive adhesive sheet and the release film of the adhesive sheet. Laminated. The laminated sheets were punched to an outer diameter of 290 mm so as to be concentric with the punched circle. Before sticking on a wafer, the release film 1 of the adhesive sheet was peeled off. In this manner, a wafer processing sheet for use with a wafer having a diameter of 200 mm, which was precut as shown in FIG. 1, was prepared.

  A silicon wafer having a diameter of 200 mm and a thickness of 100 μm was irradiated with a pulsed laser having a wavelength of 1064 nm, and an altered layer was formed inside the wafer along a planned division line of 5 mm × 5 mm.

Using a tape mounter (RAD2500, manufactured by Lintec Co., Ltd.), the silicon wafer and the ring frame (inner diameter: 250 mm) were attached to the wafer processing sheet prepared above so as to be concentric. Ultraviolet rays were irradiated (215 mW / cm ² , 170 mJ / cm ² ) from the base material surface of the adhesive sheet using an ultraviolet ray irradiation device (RAD2000, manufactured by Lintec Corporation).

  Thereafter, the wafer was divided and the adhesive layer was cleaved using an expanding apparatus. After the expansion, it was visually confirmed whether or not the chip was contaminated by the scattering of the adhesive layer.

[Example 3]
Using a dicing machine (DFD-6361, manufactured by Disco Corporation) on a silicon wafer having a diameter of 200 mm and a thickness of 720 μm, a groove having a depth of 130 μm and a chip size of 5 mm × 5 mm was formed by cutting into the wafer from the wafer surface. Next, a surface protective sheet (Adwill E-3124, manufactured by Lintec) is attached to the surface on which the groove of the wafer is formed, and a thickness of 100 μm is obtained using a back surface grinding device (DGP-8760, manufactured by Disco). The back surface of the wafer was ground and divided into chips. Thereafter, the surface protective sheet surface was irradiated with ultraviolet rays using an ultraviolet irradiation device (RAD-2000 m / 12, manufactured by Lintec Corporation) (illuminance 220 mW / cm ² , light amount 150 mJ / cm ² ).

Using a tape mounter (RAD2500, manufactured by Lintec Co., Ltd.), a silicon wafer and a ring frame (inner diameter 250 mm) divided into chips are attached to the wafer processing sheet produced in Example 2 so as to be concentric circles, The surface protection sheet was peeled off. Ultraviolet rays were irradiated (215 mW / cm ² , 170 mJ / cm ² ) from the base material surface of the adhesive sheet using an ultraviolet ray irradiation device (RAD2000, manufactured by Lintec Corporation).
Thereafter, the adhesive layer was cleaved using an expanding device. After performing the expansion, it was visually confirmed whether or not the chip was contaminated by the scattering of the adhesive layer.

[Example 4]
The pressure-sensitive adhesive sheet is die-cut to an inner diameter of 290 mm, and the pressure-sensitive adhesive layer for lamination of the pressure-sensitive adhesive sheet and the adhesive layer of the adhesive sheet are in contact with each other while peeling the release film 2 of the pressure-sensitive adhesive sheet and the release film of the adhesive sheet. Laminated. The laminated sheets were punched to an outer diameter of 380 mm so as to be concentric with the punched circle. Before sticking on a wafer, the release film 1 of the adhesive sheet was peeled off. In this manner, a wafer processing sheet for use with a wafer having a diameter of 300 mm, which was precut as shown in FIG. 1, was prepared.

Using a dicing machine (DFD-6361, manufactured by Disco Corporation) on a silicon wafer having a diameter of 300 mm and a thickness of 720 μm, grooves with a depth of 130 μm and a chip size of 5 mm × 5 mm were formed by cutting into the wafer from the wafer surface. Next, a surface protective sheet (Adwill E-3124, manufactured by Lintec) is attached to the surface on which the groove of the wafer is formed, and a thickness of 100 μm is obtained using a back surface grinding device (DGP-8760, manufactured by Disco). The back surface of the wafer was ground and divided into chips. Thereafter, the ultraviolet irradiation device for the surface protection sheet surface (RAD-2000m / 12, manufactured by Lintec Corporation) was irradiated with ultraviolet rays using a (illuminance 220 mW / cm ^2, light quantity 150 mJ / cm ^2).

Using a tape mounter (RAD2500, manufactured by Lintec Co., Ltd.), a silicon wafer and a ring frame (inner diameter 350 mm) divided into chips are affixed to the wafer processing sheet prepared in Example 2 so as to be concentric, The surface protection sheet was peeled off. Ultraviolet rays were irradiated (215 mW / cm ² , 170 mJ / cm ² ) from the base material surface of the adhesive sheet using an ultraviolet ray irradiation device (RAD2000, manufactured by Lintec Corporation).
Thereafter, the adhesive layer was cleaved using an expanding device. After performing the expansion, it was visually confirmed whether or not the chip was contaminated by the scattering of the adhesive layer.

[Comparative Example 1]
The pressure-sensitive adhesive sheet is die-cut to an inner diameter of 162 mm, and while the release film 2 of the pressure-sensitive adhesive sheet and the release film of the adhesive sheet are peeled off, the pressure-sensitive adhesive layer for stacking the pressure-sensitive adhesive sheet and the adhesive layer of the adhesive sheet are in contact with each other. Laminated. The laminated sheets were punched to an outer diameter of 220 mm so as to be concentric with the punched circle. Before sticking on the wafer, the release film of the adhesive sheet was peeled off. In this way, a wafer processing sheet was prepared that was pre-cut as shown in FIG. 3 and was used with a wafer having a diameter of 150 mm.

  The wafer was divided and the adhesive layer was cleaved in the same manner as in Example 1 except that the wafer processing sheet was used. After performing the expansion, it was visually confirmed whether or not the chip was contaminated by the scattering of the adhesive layer.

[Comparative Example 2]
The pressure-sensitive adhesive sheet is die-cut to an inner diameter of 215 mm, and the pressure-sensitive adhesive layer for the pressure-sensitive adhesive sheet and the adhesive layer of the adhesive sheet are in contact with each other while peeling the release film 2 of the pressure-sensitive adhesive sheet and the release film of the adhesive sheet. Laminated. The laminated sheets were punched to an outer diameter of 290 mm so as to be concentric with the punched circle. Before sticking on a wafer, the release film 1 of the adhesive sheet was peeled off. In this way, a wafer processing sheet for use with a wafer having a diameter of 200 mm, which was precut as shown in FIG. 3, was prepared.

  The wafer was divided and the adhesive layer was cleaved in the same manner as in Example 2 except that the wafer processing sheet was used. After performing the expansion, it was visually confirmed whether or not the chip was contaminated by the scattering of the adhesive layer.

[Comparative Example 3]
The wafer was divided into chips and the adhesive layer was cleaved in the same manner as in Example 3 except that the wafer processing sheet produced in Comparative Example 2 was used. After performing the expansion, it was visually confirmed whether or not the chip was contaminated by the scattering of the adhesive layer.
Table 1 shows the evaluation results of the above-described Examples and Comparative Examples.

[Comparative Example 4]
The pressure-sensitive adhesive sheet is die-cut to an inner diameter of 320 mm, and the pressure-sensitive adhesive layer for lamination of the pressure-sensitive adhesive sheet and the adhesive layer of the adhesive sheet are in contact with each other while peeling the release film 2 of the pressure-sensitive adhesive sheet and the release film of the adhesive sheet. Laminated. The laminated sheets were punched to an outer diameter of 380 mm so as to be concentric with the punched circle. Before sticking on a wafer, the release film 1 of the adhesive sheet was peeled off. In this way, a wafer processing sheet was prepared that was pre-cut as shown in FIG. 3 and was used with a wafer having a diameter of 300 mm.

  The wafer was divided into chips and the adhesive layer was cleaved in the same manner as in Example 4 except that the wafer processing sheet was used. After performing the expansion, it was visually confirmed whether or not the chip was contaminated by the scattering of the adhesive layer.

DESCRIPTION OF SYMBOLS 100: Sheet | seat for wafer processing concerning this invention 102: Base material 104: Adhesive layer 106: Adhesive sheet 108: Base material 110: Adhesive layer 112: Adhesive sheet for wafer contamination prevention 200: Wafer 300: Ring frame 400: Conventional Wafer processing sheet

Claims (4)

Wafer processing comprising an adhesive sheet having an adhesive layer laminated on a substrate and a ring-shaped adhesive sheet for preventing contamination of a wafer, wherein the adhesive layer for preventing wafer contamination is laminated on the adhesive layer of the adhesive sheet Seat for
The adhesive sheet for preventing wafer contamination has a size that can be fixed to a ring frame,
The wafer processing sheet, wherein an inner diameter of the wafer contamination preventing pressure-sensitive adhesive sheet is 0 to 20 mm smaller than a diameter of the wafer.   The wafer processing sheet according to claim 1, wherein the wafer has a diameter of 100 to 450 mm. Wafer processing comprising an adhesive sheet having an adhesive layer laminated on a substrate and a ring-shaped adhesive sheet for preventing contamination of a wafer, wherein the adhesive layer for preventing wafer contamination is laminated on the adhesive layer of the adhesive sheet The wafer processing sheet with the wafer attached to the entire back surface of the wafer,
The adhesive sheet for preventing wafer contamination has a size that can be fixed to a ring frame,
The wafer sticking wafer processing sheet, wherein an inner diameter of the wafer contamination preventing pressure-sensitive adhesive sheet is 0 to 20 mm smaller than a diameter of the wafer. A method for manufacturing a semiconductor device comprising a step of affixing a wafer to a wafer processing sheet, expanding the wafer processing sheet and cleaving the adhesive layer,
The wafer processing sheet comprises an adhesive sheet in which an adhesive layer is laminated on a base material and a ring-shaped wafer contamination prevention adhesive sheet, and the wafer contamination prevention adhesive on the adhesive layer of the adhesive sheet. A wafer processing sheet in which sheets are stacked, the wafer contamination preventing pressure-sensitive adhesive sheet has a size that can be fixed to a ring frame, and the wafer contamination preventing pressure-sensitive adhesive sheet has an inner diameter of 0 to 0 than the wafer diameter. A method for manufacturing a semiconductor device, wherein the wafer processing sheet is 20 mm smaller.

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