JP2023146686A - Method for manufacturing support piece - Google Patents

Abstract

To provide a method for manufacturing a support piece capable of suppressing generation of burrs on the support piece at the time of dicing.SOLUTION: A method for manufacturing a support piece includes: a fixing step of fixing a laminate L of a dicing film 13 and a support piece forming film 14 to a ring frame 18; a singulation step of singulating the support piece forming film 14 into a plurality of support pieces D by dicing with a blade B; and a pickup step of sequentially picking up the plurality of support pieces D from the dicing film 13. In the singulation step, an average particle diameter of abrasive grains 30 exposed on a surface Ba of the blade B is 3.0 μ m or more, and an area occupancy rate of the abrasive grains 30 on the surface Ba is 10% to 18%.SELECTED DRAWING: Figure 7

Description

The present disclosure relates to a method of manufacturing a support piece.

In recent years, in the field of semiconductor devices, there has been an increasing demand for higher integration, smaller size, and higher speed. One embodiment of a semiconductor device has a structure in which semiconductor chips are stacked on a controller chip arranged on a substrate. The semiconductor assembly described in Patent Document 1 has a structure called a so-called dolmen structure. This conventional semiconductor assembly includes a package substrate, a controller die disposed on the package substrate, and a memory die disposed above the controller die, with the memory die being supported by a support member such as a post.

Special table 2017-515306 publication

In the semiconductor assembly of Patent Document 1 mentioned above, a resin film with a silicon chip is used as a supporting member of a dolmen structure using the same process as in manufacturing a normal semiconductor chip. However, problems with this method include the use of relatively expensive silicon chips and the need for a wafer polishing process.

In order to solve this problem, a method of forming a support piece having a dolmen structure without using a silicon chip by dividing the film for forming the support piece into individual pieces is being considered. In this method, for example, a laminated film in which a dicing film and a supporting piece forming film are laminated on one surface of a base film can be used. However, when dicing the supporting piece forming film on the dicing film with a blade, burrs may adhere to the supporting pieces formed by dividing the supporting piece forming film into pieces. In a state where burrs are attached to the support piece, there is a possibility that a problem may occur in picking up the support piece from the dicing film. Furthermore, there is a risk that the reliability of a semiconductor device configured using the support piece may be reduced.

The present disclosure has been made to solve the above problems, and an object of the present disclosure is to provide a method for manufacturing a support piece that can suppress the attachment of burrs to the support piece during dicing.

A method for manufacturing a support piece according to one aspect of the present disclosure includes a fixing step of fixing a laminate of a dicing film and a support piece forming film provided on one side of the dicing film to a ring frame, and a fixing step for forming a support piece. The singulation process includes a singulation process of dicing a film for use with a blade into a plurality of support pieces, and a pickup process of sequentially picking up the plurality of support pieces from the dicing film. The average grain size of the abrasive grains exposed on the surface of the blade used for this purpose is 3.0 μm or more, and the area occupation rate of the abrasive grains on the surface is 10% to 18%.

In this support piece manufacturing method, in the singulation process, the average grain size of the abrasive grains exposed on the surface of the blade is 3.0 μm or more, and the area occupation rate of the abrasive grains on the surface is 10% to 18%. So-called coarse-grained blades are used. By using such a blade, the grains of the cutting pieces during dicing become relatively large, and the specific surface area of the grains of the cutting pieces becomes small. For this reason, the grains of the cutting pieces are less likely to aggregate with each other, and even if aggregation occurs, they are easy to separate again. By preventing the grains of the cut pieces from aggregating with each other, the grains of the cut pieces are easily scraped out of the grooves during dicing, and it is possible to suppress the attachment of burrs to the support pieces after singulation.

The average particle diameter of the abrasive grains may be 10 μm or less. In this case, the average grain size of the abrasive grains does not become excessive, and the flatness of the cut surface obtained by dicing can be maintained sufficiently.

The supporting piece forming film may include a thermosetting resin layer. In this case, a support piece that does not use silicon chips can be suitably produced.

The supporting piece forming film may further include a resin layer or a metal layer having higher rigidity than the thermosetting resin layer. When the support piece forming film includes a layer with high rigidity, the followability to a pickup tool such as a suction collet can be improved, although the followability to an uplifting jig is reduced. Therefore, even if the thermosetting resin layer is not subjected to thermosetting treatment, the pick-up performance of the support piece can be sufficiently ensured. When a metal layer is included, the optical contrast between the resin material and the metal material can improve the visibility of the support piece during pickup.

A plurality of thermosetting resin layers may be provided with a resin layer or a metal layer sandwiched therebetween. In this case, even if the thermosetting resin layer is not subjected to thermosetting treatment, the pick-up performance of the support piece can be more fully ensured.

According to the present disclosure, attachment of burrs to the support piece during dicing can be suppressed.

1 is a schematic cross-sectional view showing an example of a semiconductor device having a dolmen structure. 3 is a flowchart illustrating a method for manufacturing a support piece according to an embodiment of the present disclosure. (a) is a perspective view showing a fixing process, and (b) is a schematic cross-sectional view thereof. (a) is a perspective view showing the singulation process, and (b) is a schematic cross-sectional view thereof. (a) is a perspective view showing a pickup process, and (b) is a schematic cross-sectional view thereof. (a) is a schematic sectional view showing the state of burrs generated in the singulation process, and (b) and (c) are typical sectional views showing the state of the pickup process in that case. It is a figure which shows an example of the image of the surface of a blade. (a) is a schematic diagram showing the appearance of burrs in a comparative example, and (b) is a typical diagram showing the appearance of burrs in an example. (a) and (b) are typical sectional views showing a modified example of the support piece forming film. It is a figure which shows the evaluation result of the burr in an Example. It is a figure which shows the evaluation result of the burr in a comparative example.

Hereinafter, a preferred embodiment of a method for manufacturing a support piece according to one aspect of the present disclosure will be described in detail with reference to the drawings.

In the following description, the same elements will be denoted by the same reference numerals, and duplicate descriptions will be omitted. The dimensions and dimension ratios in the figures are for convenience and do not necessarily reflect actual dimensions. In this specification, numerical ranges indicated using "~" include the numerical values written before and after "~" as minimum and maximum values, respectively. The upper limit value or lower limit value of a numerical range described in stages in this specification may be replaced with the upper limit value or lower limit value of a numerical range in another stage.

In this specification, the term "layer" includes both an aspect in which the layer is formed on the entire surface of the object to be formed, and an aspect in which it is formed in a part of the object to be formed, when observed in a plan view. A "step" in this specification is not necessarily limited to an independent step, and may also include a step in which the intended effect of the step is achieved even if it cannot be clearly distinguished from other steps.

FIG. 1 is a schematic cross-sectional view showing an example of a semiconductor device having a dolmen structure. A semiconductor device 1 shown in the figure includes a substrate 2, a controller chip 3 disposed on one surface of the substrate 2, a plurality of memory chips 4, 5, and 6, and each of these chips is connected to an electrode (not shown) on the substrate 2. (shown in the figure) and a plurality of wires W that are electrically connected to each other. The controller chip 3, memory chips 4, 5, 6, and wires W are sealed with a sealing material 7.

The substrate 2 is, for example, an organic substrate. The substrate 2 may be a metal substrate such as a lead frame. A plurality of support pieces D are arranged around the controller chip 3. An adhesive layer 8 is provided on one side of the controller chip 3 and memory chips 4, 5, and 6, respectively. The controller chip 3 is fixed to the surface of the substrate 2 via an adhesive layer 8. The memory chips 4, 5, and 6 are stacked in a stepped manner with an adhesive layer 8 in between so that a connection space for the wire W is formed. The stack of memory chips 4, 5, and 6 is supported above the controller chip 3 (on the opposite side to the substrate 2) by a plurality of support pieces D via an adhesive layer 8 on one side of the bottom memory chip 4. .

Next, the manufacturing process of the support piece D mentioned above will be explained. FIG. 2 is a flowchart illustrating a method for manufacturing a support piece according to an embodiment of the present disclosure. As shown in FIG. 2, this method of manufacturing a support piece includes a fixing step (step S01), a singulation step (step S02), and a pick-up step (step S03).

In the fixing step, as shown in FIGS. 3(a) and 3(b), the laminate L of the dicing film 13 and the supporting piece forming film 14 provided on one side of the dicing film 13 is mounted on a ring frame 18. This is the process of fixing. In this embodiment, the fixing process can be carried out using a general laminating apparatus used for laminating a dicing film onto a semiconductor wafer, for example. After arranging the laminate L of the dicing film 13 and the supporting piece forming film 14 on the ring frame 18, pressure is applied by a roller to adhere the peripheral edge of the dicing film 13 to the ring frame 18. Thereby, the laminate L of the dicing film 13 and the supporting piece forming film 14 is fixed to the ring frame 18.

The dicing film 13 is a film for fixing the supporting piece forming film 14 to the ring frame 18. The dicing film 13 is formed into a circular shape having a diameter smaller than the width of the base film 12 by processing means such as punching. The dicing film 13 has a base material layer 19 and an adhesive layer 20, as shown in FIG. 3(b). The base material layer 19 is a layer that serves as the base of the dicing film 13. The base layer 19 is made of a material such as polyethylene terephthalate (PET) or polyolefin. The adhesive layer 20 is made of, for example, an ultraviolet curing adhesive. The adhesive layer 20 has a property that its adhesiveness decreases when irradiated with ultraviolet rays. The adhesive layer 20 may be a pressure-sensitive (non-UV curable) adhesive as well as an ultraviolet curable adhesive.

The support piece forming film 14 is a film for forming the support piece D (see FIG. 1) in the semiconductor device 1 described above. The supporting piece forming film 14 is formed into a circular shape having a diameter one size smaller than that of the dicing film 13 by processing means such as punching. The support piece forming film 14 is made of, for example, a thermosetting resin composition. That is, the support piece forming film 14 is constituted by the thermosetting resin layer 15.

The thermosetting resin composition constituting the support piece forming film 14 can go through a semi-cured (B stage) state and then become a completely cured product (C stage) state by a subsequent curing treatment. The thermosetting resin composition includes an epoxy resin, a curing agent, and an elastomer (eg, acrylic resin). The thermosetting resin composition further contains an inorganic filler, a curing accelerator, and the like, if necessary.

The singulation step is a step of singulating the support piece forming film 14 into a plurality of support pieces D by dicing it with a blade B, as shown in FIGS. 4(a) and 4(b). In the examples shown in FIGS. 4A and 4B, dicing is performed on the support piece forming film 14 using a grid-like cut pattern 16 when viewed from above. Here, by fully cutting the supporting piece forming film 14, a cut is made to reach from one side of the supporting piece forming film 14 to the other side. The cuts may reach the adhesive layer 20 of the dicing film 13. Due to the cut pattern 16, the support piece forming film 14 has rectangular support pieces D arranged in a matrix.

The pick-up process is a process of sequentially picking up a plurality of support pieces D from the dicing film 13, as shown in FIGS. 5(a) and 5(b). When the adhesive layer 20 is an ultraviolet curable adhesive, in the pickup step, the dicing film 13 is irradiated with ultraviolet rays to reduce the adhesive force between the dicing film 13 and the supporting piece forming film 14. When the adhesive layer 20 is a pressure-sensitive (non-ultraviolet curable) adhesive, the pick-up process can be performed without ultraviolet irradiation. Next, the support piece D is suctioned by the suction collet 25, and the support piece D is picked up. When suctioning the supporting piece D by the suction collet 25, the supporting piece D to be picked up may be pushed up from the dicing film 13 side using the lifting jig 26.

In the above-mentioned singulation process, when the supporting piece forming film 14 on the dicing film 13 is diced with the blade B, as shown in FIG. It is conceivable that burrs K may adhere to the supporting piece D. The burr K is formed by, for example, agglomeration of cut pieces of the resin material constituting the support piece forming film 14, cut pieces of the resin material constituting the adhesive layer 20 of the dicing film 13, etc. This may occur within the groove 27 formed between the holes D.

The burr K generated in the groove 27 adheres to the side surface of the support piece D, etc. When burrs are attached to the support piece D, as shown in FIG. 6(b), the force required to peel the support piece D from the dicing film 13 during pick-up increases, which may result in pick-up failure. . Further, as shown in FIG. 6(c), the support piece D is picked up with the burr K attached, and the burr K gets mixed into the semiconductor device 1 configured using the support piece D. It is conceivable that the reliability of

On the other hand, in the method for manufacturing a support piece according to the present embodiment, in the singulation process, the average grain size of the abrasive grains 30 exposed on the surface Ba of the blade B used for dicing is 3.0 μm or more. There is. Further, the area occupation rate of the abrasive grains 30 on the surface Ba of the blade B is 10% to 18%. The average particle diameter of the abrasive grains 30 may be 5.3 μm or more, or 7.5 μm or more. The area occupation rate of the abrasive grains 30 may be 12.5% to 17.5%, or may be 12.5% to 15%. The average particle size of the abrasive grains is 10 μm or less.

FIG. 7 is a diagram showing an example of an image of the surface of a blade that satisfies the average grain size and area occupation rate of abrasive grains. In the example shown in the figure, the average grain size of the abrasive grains 30 exposed on the surface Ba of the blade B is 5.3 μm, and the area occupation rate of the abrasive grains 30 on the surface Ba of the blade B is 12.5%. It becomes. The abrasive grains 30 are evenly dispersed on the surface Ba of the blade B.

Blade B as described above is a so-called coarse-grained blade in which the abrasive grains 30 in the portions that come into contact with the supporting piece forming film 14 and the dicing film 13 during dicing are coarse and are dispersed at a constant ratio on the surface. There is. When a so-called fine-grained blade that does not satisfy this condition is used, the grains P of the cutting pieces of the support piece forming film 14 and the dicing film 13 become relatively fine, as shown in FIG. Since the specific surface area of the grains P increases, the grains P of the cutting pieces tend to aggregate with each other. When the aggregated grains P of the cutting pieces enter the groove 27 between the support pieces D and D, they become difficult to be scraped out by the blade B, and the aggregates of the grains P of the cutting pieces remaining in the groove 27 are removed as burrs K from the support piece D. Attach to.

On the other hand, when a coarse-grained blade that satisfies the above conditions is used, as shown in FIG. Since the specific surface area of the grains P of the cut piece becomes small, the grains P of the cut piece become difficult to aggregate with each other. Furthermore, even if agglomeration occurs, the particles P of the cutting pieces are likely to separate again. Therefore, even if the grains P of the cut pieces enter the groove 27 between the support pieces D, they are easily scraped out by the blade B, and adhesion of burrs K to the support piece D can be suppressed.

The average grain size and area occupancy of the abrasive grains on the surface of the blade can be measured using a three-dimensional shape measuring device (for example, LEXT OLS4100 manufactured by Olympus Corporation). In this case, the image processing conditions are such that the measurement area is within 200 μm x 200 μm, and the image of the surface Ba of the blade B obtained in the particle analysis mode is subjected to binarization processing to extract the abrasive grain area in the image. The threshold value used for extracting the abrasive grains can be, for example, 0% or more and 99% or less.

Based on the area of the abrasive grains in the extracted image, the average particle diameter and area occupancy rate of the abrasive grains on the surface of the blade are calculated. When calculating the average particle size, if the particle size of abrasive grains is more than three times the manually measured average particle size (for example, assuming the number of samples is 20), it will be treated as a foreign substance and will not be calculated. May be excluded. The area occupancy rate can be calculated by summing the areas of the extracted abrasive grains and dividing the sum by the area of the blade surface.

As explained above, in this support piece manufacturing method, in the singulation step, the average grain size of the abrasive grains 30 exposed on the surface Ba of the blade B is 3.0 μm or more, and the abrasive grains 30 on the surface Ba So-called coarse-grained blades with an area occupation rate of 10% to 18% are used. By using such a blade B, the grains P of the cutting pieces become relatively large during dicing, and the specific surface area of the grains P of the cutting pieces becomes small. For this reason, the grains P of the cutting pieces are less likely to aggregate with each other, and even if aggregation occurs, they are easy to separate again. By preventing the grains P of the cut pieces from aggregating with each other, the grains P of the cut pieces are easily scraped out of the grooves 27 during dicing, and the adhesion of burrs K to the support pieces D after singulation is suppressed. can.

By suppressing the adhesion of the burr K to the support piece D, an increase in the force required to peel the support piece D from the dicing film 13 at the time of pickup can be suppressed, and pickup defects can be suppressed. Further, it is possible to suppress the burr K from being mixed into the semiconductor device 1 configured using the support piece D, and it is possible to suppress a decrease in the reliability of the semiconductor device 1.

In this embodiment, the average grain size of the abrasive grains 30 is 10 μm or less. According to this range, the average grain size of the abrasive grains 30 does not become excessive, and the flatness of the cut surface obtained by dicing can be sufficiently maintained. Therefore, the accuracy of the shape of the support pieces D can be ensured while suppressing the adhesion of burrs K to the support pieces D after singulation.

In this embodiment, the supporting piece forming film 14 includes a thermosetting resin layer. Thereby, the support piece D that does not use a silicon chip can be suitably produced.

The present disclosure is not limited to the above embodiments. For example, in the above embodiment, the supporting piece forming film 14 is constituted by the thermosetting resin layer 15, but as shown in FIG. The structure may further include a resin layer 31 or a metal layer 32 having higher rigidity. As the resin layer 31, for example, a polyimide layer is used. As the metal layer 32, for example, a copper layer, an aluminum layer, etc. are used.

In this case, since the support piece forming film 14 includes a highly rigid layer, the followability to the uplifting jig 26 is reduced, but the followability to the pickup tool such as the suction collet 25 can be improved. . Therefore, even if the thermosetting resin layer 15 is not subjected to thermosetting treatment, the pick-up performance of the supporting piece D can be sufficiently ensured. When the metal layer 32 is included, the optical contrast between the resin material and the metal material can improve the visibility of the support piece D during pickup.

As shown in FIG. 9(b), a plurality of thermosetting resin layers 15 may be provided so that the resin layer 31 or the metal layer 32 is sandwiched therebetween. Even in this case, even if the thermosetting resin layer 15 is not subjected to thermosetting treatment, the pick-up performance of the support piece D can be more fully ensured. In the example of FIG. 9(b), one thermosetting resin layer 15 is provided on one side and the other side of the resin layer 31 or the metal layer 32. A plurality of thermosetting resin layers 15 may be provided on the other side.

Hereinafter, an effect confirmation test of the method for manufacturing a support piece according to the present disclosure will be described. In this test, dicing of the support piece forming film was performed using the blade according to the example and the blade according to the comparative example. This is an evaluation of the quality.

FIG. 10 is a diagram showing the evaluation results of burrs according to the example. As shown in the figure, in Example 1, the thickness of the supporting piece forming film for dicing was 80 μm, and the width of the blade was 32.5 μm. The average grain size of the abrasive grains on the surface of the blade (hereinafter referred to as the "surface grain size") is an actual value of 5.3 μm, and the area occupation rate of the abrasive grains on the blade surface (hereinafter referred to as the "surface occupancy rate") is 5.3 μm. The value was 10.0%. In FIG. 10, literature values are added for the surface particle size and surface occupancy. Abrasive grains with an average particle diameter of 44 μm or less are not specified in the JIS standard, so the values in the literature are just reference values (https://www.toishi.info/spec/grit.html).

In Example 2, the same conditions as in Example 1 were used except that the thickness of the support piece forming film was 65 μm. In Example 3, the same conditions as in Example 1 were used except that the width of the blade was 22.5 μm. In Example 4, the same conditions as in Example 1 were used, except that the thickness of the supporting piece forming film was 65 μm and the width of the blade was 22.5 μm. In Example 5, the width of the blade was 22.5 μm, the surface grain size was 3.4 μm, and the surface occupation rate was 10.9%. In Example 6, the surface occupancy was 17.2%. In Example 7, the thickness of the supporting piece forming film was 65 μm, the surface grain size was 6.9 μm, and the surface occupancy was 15.5%.

Regarding the height of the burr, the maximum length of the burr generated in the groove between the support pieces in the height direction of the support piece (thickness direction of the film for forming the support piece) was taken as the measured value. A digital microscope (manufactured by Mitutoyo Co., Ltd.: MF-UD) was used to measure the height of the burr. As a result, the height of the burr was 7.97 μm in Example 1, 9.27 μm in Example 2, 16.37 μm in Example 3, 12.37 μm in Example 4, and 12.37 μm in Example 5. In Example 6, it was 8.60 μm, and in Example 7, it was 6.50 μm. Although the height of the burr varies depending on the thickness of the supporting piece forming film and the width of the blade, in all Examples 1 to 7, the height of the burr was suppressed to less than 20 μm. In Examples 1, 2, 6, and 7, the height of the burr was suppressed to less than 10 μm.

FIG. 11 is a diagram showing the evaluation results of burrs in a comparative example. As shown in the figure, in Comparative Example 1, the same conditions as in Example 1 were used except that the surface particle size was 1.8 μm. In Comparative Example 1, the surface occupancy was actually measured to be 9.7%. In Comparative Example 2, the same conditions as Comparative Example 1 were used except that the thickness of the support piece forming film was 65 μm.

In Comparative Example 3, the same conditions as Comparative Example 1 were used except that the width of the blade was 22.5 μm. In Comparative Example 4, the conditions were the same as in Comparative Example 1, except that the thickness of the supporting piece forming film was 65 μm and the width of the blade was 22.5 μm. In Comparative Example 5, the same conditions as in Example 1 were used, except that the surface occupancy was actually measured at 18.9%.

As a result, the height of the burrs was 23.13 μm in Comparative Example 1, 22.32 μm in Comparative Example 2, 34.17 μm in Comparative Example 3, 35.07 μm in Comparative Example 4, and 35.07 μm in Comparative Example 5. It was 24.18 μm. As in the Examples, the height of the burrs varied depending on the thickness of the supporting piece forming film and the width of the blade, but in Comparative Examples 1 to 5, the height of the burrs exceeded 20 μm in all cases. In Comparative Examples 3 and 4, the height of the burrs exceeded 30 μm.

From the above results, in the singulation process, the average grain size (surface grain size) of the abrasive grains exposed on the surface of the blade used for dicing is set to 3.0 μm or more, and the area occupation rate of the abrasive grains on the surface ( It was confirmed that setting the surface occupancy rate to 10% to 18% contributes to suppressing the adhesion of burrs to the support pieces during dicing.

13... Dicing film, 14... Support piece forming film, 15... Thermosetting resin layer, 18... Ring frame, 30... Abrasive grain, 31... Resin layer, 32... Metal layer, B... Blade, Ba... Surface, D ...Support piece, L...Laminated body.

Claims (5)

a fixing step of fixing a laminate of a dicing film and a supporting piece forming film provided on one side of the dicing film to a ring frame;
a singulating step of singulating the supporting piece forming film into a plurality of supporting pieces by dicing with a blade;
a pickup step of sequentially picking up the plurality of support pieces from the dicing film,
In the singulation step, the average grain size of the abrasive grains exposed on the surface of the blade used for dicing is 3.0 μm or more, and the area occupation rate of the abrasive grains on the surface is 10% to 18%. % manufacturing method of support piece. The method for manufacturing a support piece according to claim 1, wherein the abrasive grains have an average particle size of 10 μm or less. 3. The method for manufacturing a support piece according to claim 1, wherein the support piece forming film includes a thermosetting resin layer. 4. The method for manufacturing a support piece according to claim 3, wherein the support piece forming film further includes a resin layer or a metal layer having higher rigidity than the thermosetting resin layer. 5. The method of manufacturing a support piece according to claim 4, wherein a plurality of the thermosetting resin layers are provided so as to sandwich the resin layer or the metal layer.

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