JP2012084760A - Dicing/die-bonding tape - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a dicing/die-bonding tape capable of surely splitting a die-bonding layer in an X-direction and a Y-direction even when stress expanding outward in a radial direction is applied to a dicing tape.SOLUTION: There is provided a dicing/die-bonding tape 1 in which a dicing tape 5 having a circular shape in a plan view is directly or indirectly stacked on a die-bonding layer 3 formed from a viscous adhesive layer and a plurality of notches 5c or cuttings are formed on an outer peripheral edge of the dicing tape 5. Each of the notches 5c or the cuttings includes portions 5c1 and 5c2 extending in a direction parallel to a first straight line and in a direction parallel to a second straight line respectively so as to facilitate extension of the dicing tape, when tensile stress expanding outward in a radial direction is applied to the dicing tape in a direction parallel to the first straight line passing through the center of the circular dicing tape and when tensile stress expanding outward in a radial direction is applied to the dicing tape in a direction parallel to the second straight line orthogonal to the first straight line.

Description

  The present invention relates to a dicing die bonding tape used for dicing a semiconductor wafer after dicing and dividing into individual semiconductor chips, and more particularly, a die made of an adhesive. The present invention relates to a dicing die bonding tape in which a dicing tape is laminated on a bonding film layer directly or via another layer.

  As a method for cutting a semiconductor chip from a semiconductor wafer, a dicing method called a first dicing method is used. For example, Patent Document 1 below discloses an example of a prior dicing method.

  In the tip dicing method described in Patent Document 1, first, a cut is formed from one surface of a circular semiconductor wafer. This cut is formed so as to extend in the X direction, which is an arbitrary direction in the plane of the semiconductor wafer, and in the Y direction, which is a direction orthogonal to the X direction. Next, a protective sheet is affixed on the semiconductor wafer surface on which the cuts are formed. After that, grinding is performed from the surface opposite to the surface on which the protective sheet of the semiconductor wafer is pasted to the portion where the cut is formed. In this way, the semiconductor wafer is divided into individual semiconductor chips. Thereby, a large number of thin semiconductor chips can be formed.

  On the other hand, as described in Patent Document 2 below, there is also known a method of irradiating a pulse laser while focusing on a region of a semiconductor wafer to be diced. In this case, the laser beam is applied to the dividing lines extending in the X direction and the Y direction for modification. Since the strength of the modified region decreases, the semiconductor wafer can be divided into individual semiconductor chips by applying an external force in the surface direction.

  By the way, as described in Patent Document 2, in order to mount individual semiconductor chips on a substrate from a semiconductor wafer that has been diced in advance or a semiconductor wafer in which a divided region has been modified by irradiation with the laser beam, Conventionally, an adhesive film called a bonding film has been used.

  That is, a die bonding film is laminated on the back surface of a semiconductor wafer that has been diced in advance or a semiconductor wafer on which the altered region is formed, and an expandable dicing tape is laminated on the opposite surface of the die bonding film. Next, an annular dicing ring is attached to the dicing tape. Then, the dicing tape is pushed up by a cylindrical split jig to expand the dicing tape. Thereby, the semiconductor wafer is divided into individual semiconductor chips by expanding the space between the semiconductor chips of the semiconductor wafer previously diced or by applying an external force to the semiconductor wafer having the altered layer provided on the dividing line. Due to this external force, the die bonding film is also divided together with the semiconductor chip. Thereby, the die bonding film is also singulated. Therefore, the semiconductor chip can be taken out together with the individual die bonding film on the lower surface of the semiconductor chip, and can be mounted on the substrate.

  Patent Document 2 discloses a method of irradiating an electromagnetic wave such as infrared light to a die bonding film in order to facilitate the division of the die bonding film by the external force.

  Patent Document 3 below discloses a method of cooling the die bonding film below the glass transition temperature of the resin constituting the film in order to facilitate the splitting of the die bonding film. .

JP 2006-245467 A JP 2006-80142 A JP 2007-27250 A

  As described above, when picking up the semiconductor chip together with the die bonding film from the structure in which the die bonding film is laminated on the semiconductor wafer having been diced in advance or the semiconductor wafer on which the altered layer is formed, the dicing tape is expanded It was necessary to split the die bonding film. In this case, the cylindrical split jig is brought into pressure contact with the dicing tape, and the dicing tape is pulled radially outward. Thereby, the die bonding film is split along the dicing lines and splitting lines extending in the X direction and the Y direction.

  In this case, as shown in a schematic plan view in FIG. 9, in the structure in which the die bonding layer 102 is laminated on the lower surface of the dicing tape 101, a stress spreading radially outward is applied to the dicing tape 101. This stress is given by pressing the dicing tape 101 with a cylindrical split jig. Therefore, as indicated by the arrows in the figure, the tensile stress acts radially outward from the center of the circular dicing tape 101.

  On the other hand, the line to be split in the die bonding layer 102 extends in the X direction and the Y direction as described above. Therefore, the tensile stress applied to the dicing tape may not surely split the die bonding layer along the line to be split. That is, when the arrow X direction and the Y direction in FIG. 9 are the directions of the lines to be split in the die bonding layer 102, the portions on both sides of the line to be split extending in the Y direction are applied in the portion where the stress applied in the direction indicated by X1 acts. The die bonding layer is reliably split. On the other hand, as shown by an arrow A, for example, in a portion where stress is applied in a direction crossing the X direction or Y direction obliquely, die bonding on both sides of the cut extending in the X direction or Y direction by the tensile stress. The layer sometimes did not split well. For this reason, a pickup failure of the semiconductor chip may occur.

  An object of the present invention is to provide a dicing die bonding tape capable of reliably splitting a die bonding layer along a line to be split extending in the X direction and the Y direction when a tensile stress is applied to the dicing tape by a dicing ring. There is.

  The present invention is a dicing die bonding tape used for picking up a semiconductor chip together with a die bonding layer from a semiconductor wafer. The dicing die bonding tape according to the present invention includes a die bonding layer made of an adhesive and a dicing tape layer laminated on one surface side of the die bonding layer and having a circular planar shape. In the present invention, a plurality of notches or notches are formed in the outer peripheral edge of the dicing tape layer, and the plurality of notches or notches are parallel to a first straight line passing through the center of the circular dicing tape. The dicing tape when a radially outward tensile stress is applied in a direction and when a radially outward tensile stress is applied in a direction parallel to a second straight line orthogonal to the first straight line. In order to facilitate the extension of the first straight line, the first straight line has a portion extending in a direction parallel to the first straight line and a second parallel line.

  In a specific aspect of the dicing die-bonding tape according to the present invention, a base material layer laminated between the die bonding layer and the dicing tape layer is further provided, and the die of the base material layer is provided. The portion in contact with the bonding layer is made of a non-adhesive material. In this case, the semiconductor chip can be easily peeled from the base material layer together with the die bonding layer after splitting the die bonding layer. Therefore, pickup failure is less likely to occur.

  In another specific aspect of the dicing die bonding tape according to the present invention, the planar shape of the die bonding layer is circular. When the dicing tape and the die bonding layer are circular, the dicing ring can be easily brought into contact with the annular region outside the die bonding layer.

  In the dicing die bonding tape according to the present invention, the dicing tape layer has a plurality of notches or notches having portions extending in a direction parallel to the first straight line and a direction parallel to the second straight line. When a tensile stress outward in the radial direction is applied to the dicing tape, the stress surely acts in a direction parallel to the first and second straight lines. Therefore, when the tensile stress is applied to the dicing tape, the die bonding layer can be reliably split into the die bonding layer portions of individual semiconductor chips. Therefore, it becomes possible to remarkably reduce the pick-up failure of the semiconductor chip.

(A) is a top view of the dicing tape layer of the dicing die-bonding tape which concerns on one Embodiment of this invention, (b) is front sectional drawing of this dicing die-bonding tape. It is a top view which shows the dicing die-bonding tape row | line | column in which the dicing die-bonding tape of this invention is formed in multiple numbers. It is a schematic plan view for demonstrating the semiconductor wafer diced first. (A) is a top view which shows the state which laminated | stacked the dicing die-bonding tape on the semiconductor wafer, and affixed the dicing ring on the dicing tape, (b) is the front sectional drawing. It is front sectional drawing for demonstrating the process of picking up a semiconductor chip from a semiconductor wafer using the dicing die-bonding tape of one Embodiment of this invention. (A) And (b) is a figure for demonstrating the process which makes a split jig contact | abut to a dicing tape, (a) is corresponded to the direction in alignment with the A1-A1 line in Fig.4 (a). It is a partial notch front sectional drawing of a part, (b) is a partially notched front sectional view equivalent to the direction in alignment with the A2-A2 line in Fig.4 (a). It is front sectional drawing which shows the state which split the die-bonding layer in the case of picking up a semiconductor chip using the dicing die-bonding tape of one Embodiment of this invention. It is a schematic plan view for demonstrating the dicing die-bonding tape which concerns on other embodiment of this invention. It is a typical top view for demonstrating the problem of the conventional dicing die-bonding tape.

  Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention with reference to the drawings.

  FIG.1 (b) is front sectional drawing which shows the dicing die-bonding tape which concerns on one Embodiment of this invention. The dicing die bonding tape 1 has a long release layer 2. The release layer 2 is made of an appropriate synthetic resin such as polyethylene terephthalate. The surface of the release layer 2 may be subjected to a release treatment.

  A die bonding layer 3 is formed on the release layer 2. The die bonding layer 3 is a layer used as a die bonding agent for semiconductor chips. That is, the die bonding layer 3 is used for bonding a semiconductor chip to a substrate or another semiconductor chip.

  The die bonding layer 3 is made of an appropriate adhesive.

  As will be described later, the die bonding layer 3 is a portion to which a circular semiconductor wafer is attached. In this embodiment, the die bonding layer 3 has a circular planar shape. However, the die bonding layer 3 may have a shape other than a circle.

  A base material layer 4 is laminated so as to cover the die bonding layer 3. The base material layer 4 can be formed using, for example, an active energy ray-curable or thermosetting adhesive composition. In order for the base material layer 4 to have non-adhesiveness, the irradiation amount of the active energy rays may be increased. In order to make the base material layer 4 have adhesiveness, it is only necessary not to irradiate active energy rays or to reduce the irradiation amount of active energy rays.

  The base material layer 4 is preferably formed of a composition containing an acrylic polymer. The base material layer 4 is preferably formed of a crosslinked body obtained by crosslinking a composition containing an acrylic polymer. Further, the polarity, storage elastic modulus, or elongation at break of the base material layer 4 can be easily controlled and designed.

  The acrylic polymer is not particularly limited. The acrylic polymer is preferably a (meth) acrylic acid alkyl ester polymer. As the (meth) acrylic acid alkyl ester polymer, a (meth) acrylic acid alkyl ester polymer having an alkyl group having 1 to 18 carbon atoms is suitably used. By using the (meth) acrylic acid alkyl ester polymer having an alkyl group having 1 to 18 carbon atoms, the polarity of the base material layer 4 can be made sufficiently low, and the surface energy of the base material layer 4 can be made low. And the peelability from the base material layer 4 of the die-bonding layer 3 can be made high.

  The composition preferably contains at least one of an active energy ray reaction initiator and a thermal reaction initiator, and more preferably contains an active energy ray reaction initiator. The active energy ray reaction initiator is preferably a photoreaction initiator.

  The active energy rays include ultraviolet rays, electron rays, α rays, β rays, γ rays, X rays, infrared rays and visible rays. Among these active energy rays, ultraviolet rays or electron beams are preferable because they are excellent in curability and hardened products are hardly deteriorated.

  As the photoreaction initiator, for example, a photo radical generator or a photo cation generator can be used. Examples of the thermal reaction initiator include a thermal radical generator. An isocyanate-based crosslinking agent may be added to the composition in order to control the adhesive force.

  A dicing tape 5 is laminated so as to cover the base material layer 4. The dicing tape 5 has a tape body layer 5a and an adhesive layer 5b provided on the lower surface of the tape body layer 5a.

  The tape body layer 5a is made of an appropriate synthetic resin such as polyethylene or polypropylene. However, polyolefin such as polyethylene and polypropylene is suitable because it has excellent expandability during dicing, which will be described later, and has a low environmental load.

The dicing-die bonding tape 1 of the present embodiment is characterized in that the dicing tape 5 has a plurality of notches 5c shown in FIG.

  In the present embodiment, the notch 5c is formed by cutting the dicing tape 5 at the outer peripheral edge.

  The notch 5c has a portion 5c1 extending in the X direction which is the first direction in FIG. 1A and a portion 5c2 extending in the Y direction which is a second direction orthogonal to the X direction. The X direction and the Y direction are directions orthogonal to each other in the plane of the dicing tape 5. Further, as will be described later, the semiconductor wafer is laminated so that the portions 5c1 and 5c2 parallel to the cutting lines in the X direction and the Y direction formed on the semiconductor wafer for separating the semiconductor wafer into semiconductor chips are located. The die bonding layer is split. This point will be described in detail in a semiconductor chip pickup method described later.

  In FIG. 1A, four notches 5 c are arranged at equal intervals in the circumferential direction of the outer peripheral edge of the dicing tape 5. But the number of the some notches 5c is arbitrary if it is two or more, and each notch 5c should just have the said parts 5c1 and 5c2.

  The depth of the notch is preferably less than or equal to the dimension where the innermost part of the notch reaches the outer peripheral edge of the semiconductor wafer, and the dimension where the innermost part of the notch is located on the inner side than the inner edge of the dicing ring. The above is preferable. More preferably, it is desirable that the innermost part of the notch is equal to or smaller than a portion located 2 mm outside the outer peripheral edge of the semiconductor wafer in the radial direction, and the innermost part of the notch is diced from the inner edge of the dicing ring. It is desirable to be located on the inner side rather than the position 5 mm away from the inner side in the radial direction of the ring. When the outermost peripheral edge of the semiconductor wafer or the innermost part of the notch is located inside the outer peripheral edge, when the dicing tape is attached to the semiconductor wafer, a part of the notch may enter the semiconductor wafer surface. If the innermost part of the notch is positioned outside the inner edge of the dicing ring, the effect of providing the notch may be impaired.

  Since the notch 5c has the portions 5c1 and 5c2, when a tensile stress is applied to the outer side in the radial direction of the dicing tape 5, the stress sufficiently acts in the X direction and the Y direction. Therefore, as will be described later, the die bonding layer 3 stacked on the semiconductor wafer can be reliably split along the cutting lines along the X direction and the Y direction.

  In the actual product, a plurality of dicing-die bonding tape laminated structures shown in FIG. 1B are formed on a long release layer 2 as shown in FIG.

  A method of picking up a semiconductor chip using the dicing die bonding tape 1 will be described with reference to FIGS.

  FIG. 3 is a schematic plan view for explaining the pre-diced semiconductor wafer. A disk-shaped semiconductor wafer 7 is laminated on a protective sheet 8. The surface of the protective sheet 8 on which the semiconductor wafer 7 is bonded has adhesiveness. Due to this adhesiveness, the semiconductor wafer 7 is attached to the protective sheet 8.

  The material constituting the protective sheet 8 is not particularly limited, and an appropriate synthetic resin film such as polyethylene terephthalate provided with an adhesive layer on one side can be used. Further, the protective sheet 8 itself may be formed of an acrylic adhesive film.

  The disk-shaped semiconductor wafer 7 laminated on the protective sheet 8 is diced by a known tip dicing method. That is, the semiconductor wafer 7 is cut along a plurality of dicing lines X1 extending in the X direction and a plurality of dicing lines Y1 extending in the Y direction. As a result, the semiconductor wafer 7 is an aggregate of a plurality of individual semiconductor chips 7a.

  As shown in FIG. 4B, a stacked body in which a semiconductor wafer 7 that has been diced on the upper surface of the protective sheet 8 is stacked is disposed on the stage 10. A dicing ring 11 is arranged on the stage 10 so as to surround the semiconductor wafer 7.

  On the other hand, in the dicing die bonding tape 1 shown in FIG. 1B, the release layer 2 is peeled off, and the die bonding layer 3 is bonded to the semiconductor wafer 7 so that the dicing shown in FIG. -The die bonding tape 1 is laminated on the semiconductor wafer 7. Thereby, the die bonding layer 3 is bonded to the semiconductor wafer 7. In this case, the adhesive force between the die bonding layer 3 and the semiconductor wafer 7 is higher than the adhesive force between the die bonding layer 3 and the base material layer 4. The dicing tape 5 is attached to the dicing ring 11.

  Thereafter, the laminated body having the semiconductor wafer 7 and the dicing die bonding tape 1 is separated from the stage 10 together with the dicing ring 11. Then, the laminate is turned upside down and placed above the cylindrical split jig 13 as shown in FIG.

  Thereafter, the protective sheet 8 bonded to the semiconductor wafer 7 is peeled off. As a result, as shown in FIGS. 6A and 6B, the surface of the semiconductor wafer 7 is exposed. In this case, FIG. 6A shows a cross section corresponding to a portion along the line A1-A1 in FIG. 4A, and FIG. 6B corresponds to a portion along the line A2-A2. That is, FIG. 6A shows a cross section of a portion where the notch 5c is provided in the dicing tape 5, and FIG. 6B shows a cross section of a portion where the notch 5c is provided. It is shown.

  Next, the cylindrical split jig 13 is moved relatively upward as indicated by the arrows in FIGS. 6A and 6B, and the dicing tape 5 is pushed up. Accordingly, as shown in FIG. 7, tensile stress extending radially outward from the center of the dicing tape 5 is applied to the dicing tape 5. As a result, in the semiconductor wafer 7 stacked on the dicing tape 5 and the die bonding layer 3, the interval between the adjacent semiconductor chips 7a is widened. In other words, the semiconductor chips on both sides of the dicing line extending in the X direction and the Y direction are separated from each other. At the same time, the die bonding layer 3 located on the upper surface of the base material layer 4 is split into a plurality of die bonding layers 3a along the dicing lines extending in the X direction and the Y direction.

  In the present embodiment, the splitting in the die bonding layer 3 is reliably performed. As described above, in the conventional dicing die bonding tape shown in FIG. 9, the die bonding layer may not be reliably split depending on the direction of the stress applied to the outer side in the radial direction. On the other hand, in the dicing die bonding tape 1 of the present embodiment, the notch 5c has portions 5c1 and 5c2 extending in the X direction and the Y direction. Therefore, even if a tensile stress toward the radially outer side is generated in the dicing tape 5, the directions indicated by the arrows Xa, -Xa and Ya, -Ya in FIG. 1 are dominant. For example, in FIG. 1A, a portion 5d pulled by an arrow Ya has notches 5c and 5c on both sides having portions 5c2 and 5c2, and therefore the tensile stress in the portion 5d is dominant in the direction indicated by the arrow Ya. Become. Similarly, in the portion 5e in FIG. 1A, the notches 5c and 5c on both sides have the portions 5c1 and 5c1 extending in the Y direction, so that the direction in which the tensile stress is applied is dominant in the Xa direction.

  Therefore, even if the dicing tape 5 is pushed up by the split jig 13 and a tensile stress is applied, the tensile stress mainly acts radially outward in the X direction and the Y direction in the dicing tape 5.

  Therefore, the dicing line of the semiconductor wafer 7 and the splitting direction of the die bonding layer are the X direction and the Y direction, and are parallel to the extending direction of the portions 5c1 and 5c2 of the notch 5c. By stacking the semiconductor wafer 7 on the die bonding layer 3, the die bonding layer 3 can be reliably split along the X direction and the Y direction.

  Therefore, in the pickup method of the present embodiment, the semiconductor chip 7a can be reliably picked up together with the split die bonding layer 3a and bonded onto the substrate or another semiconductor chip. Therefore, pickup defects can be remarkably reduced.

  FIG. 8 is a schematic plan view for explaining a modification of the dicing die-bonding tape of the present invention. In FIG. 8, a structure in which the dicing die bonding tape 1 is laminated on the dicing ring 11 is schematically shown. That is, the state shown in FIG. 1A in the above-described embodiment is shown in FIG.

  In this modification, a plurality of cuts 5f are formed instead of the plurality of cutouts 5c. The cut 5f is provided by forming a cutting line so as to penetrate from the upper surface to the lower surface of the dicing tape 5 without completely cutting a part of the dicing tape 5. The notch 5f has portions 5f1 and 5f2 extending in the X direction and the Y direction, similarly to the notch 5c. As described above, even when the notch 5f having the portions 5f1 and 5f2 extending in the X direction and the Y direction is formed instead of the notch 5c, the dicing ring 11 makes it possible to remove the outer side in the radial direction. Even if a tensile stress applied to the dicing tape 5 is applied, the tensile stress can be applied to the dicing tape 5 predominantly in the X direction and the Y direction.

  In this modification, the cut 5f is provided so as to penetrate the dicing tape 5, but the cut 5f may be formed to a depth at which the dicing tape 5 is half-cut.

  The base material layer 4 is not necessarily provided, and the die bonding layer 3 may be directly attached to the dicing tape 5.

  In the above embodiment, the semiconductor wafer 7 that has been diced, that is, the semiconductor wafer 7 that is diced along dicing lines extending in the X direction and the Y direction is used. However, as described in Patent Document 2, the present invention may use a semiconductor wafer in which an altered layer extending in the X direction and the Y direction, that is, a splitting induction line is formed. Similar to the above embodiment, the dicing die bonding tape 1 is laminated on such a semiconductor wafer, the dicing tape 5 is pushed up by a cylindrical split jig, and the dicing tape 5 is pulled radially outward. The bonding layer 3 can be reliably split along the X direction and the Y direction. In this case, simultaneously with the splitting of the die bonding layer 3, the semiconductor wafer is also split along the splitting induction lines extending in the X direction and the Y direction.

DESCRIPTION OF SYMBOLS 1 ... Dicing-die bonding tape 2 ... Release layer 3, 3a ... Die bonding layer 4 ... Base material layer
DESCRIPTION OF SYMBOLS 5 ... Dicing tape 5a ... Tape main body layer 5b ... Adhesive layer 5c ... Notch 5c1, 5c2 ... Part 5d, 5e ... Part 5f ... Notch 5f1, 5f2 ... Part 7 ... Semiconductor wafer 7a ... Semiconductor chip 8 ... Protective sheet 10 ... Stage 11 ... Dicing ring 13 ... Split jig

Claims (3)

A semiconductor chip is taken out together with a die bonding layer from a semiconductor wafer or a semiconductor wafer in which a splitting induction line extending in the X direction and the Y direction is formed along a dicing line extending in the Y direction which is a direction orthogonal to the X direction and the X direction. Dicing-die bonding tape used for
A die bonding layer made of an adhesive; and
It is laminated on one surface side of the die bonding layer, and includes a dicing tape layer having a circular planar shape,
A plurality of notches or notches are formed in the outer peripheral edge of the dicing tape layer, and the plurality of notches or notches are radially in a direction parallel to a first straight line passing through the center of the circular dicing tape. Accelerates the dicing tape elongation when an outward tensile stress is applied and when a radially outward tensile stress is applied in a direction parallel to a second straight line orthogonal to the first straight line The dicing die bonding tape has a portion extending in a direction parallel to the first straight line and a direction parallel to the second straight line.   The base material layer laminated | stacked between the said die bonding layer and the said dicing tape layer is further provided, The part which contact | connects the said die bonding layer of this base material layer consists of non-adhesive material. The dicing-die bonding tape described. The dicing die bonding tape according to claim 1 or 2 whose plane shape of said die bonding layer is circular.

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