JP7172022B2 - Semiconductor device manufacturing method - Google Patents

Description

The present invention relates to a method of manufacturing a semiconductor device mounted on various electronic equipment.

Semiconductor devices mounted on general electronic equipment have hitherto been mainly lead frame packages in which a semiconductor is mounted on a metal lead frame and sealed, and packages mounted on an organic substrate. On the other hand, along with the miniaturization and high performance of electronic equipment, the size of the package to be mounted is also progressing, and the wafer level package in which bumps to be connected to the substrate are directly formed on the bump surface of the semiconductor element is increasing. Furthermore, the number of bumps is increasing and wiring is becoming finer, and there is a growing demand for fan-out wafer-level packages in which wiring is drawn out to an insulating layer larger than the size of a semiconductor element.

There are various methods for manufacturing fan-out wafer level packages, but one method for forming multiple layers of fine wiring is to place the bump surface of the semiconductor element on top of the adhesive layer formed on the carrier. There is a chip-first/face-up process in which the semiconductor element is sealed after being mounted. The adhesive layer used here is used as a temporary fixing material and is generally peeled off after going through several processes such as encapsulation of the semiconductor element, grinding of the encapsulant, and formation of the wiring layer. In this case, the adhesive layer not only needs to have excellent heat resistance to withstand several high-temperature processes, but also the back surface of the semiconductor element is exposed after the temporary fixing material that becomes the adhesive layer is peeled off. It is necessary to form a back surface protective material for the purpose of chip protection and the like.

Several methods have been proposed for peeling off the adhesive layer on which the semiconductor element is mounted. As for the protection of the back surface of the semiconductor element, a method of preliminarily forming the semiconductor element on the back surface of the wafer described in Patent Document 2 and then singulating the semiconductor element is generally used.

Japanese Patent No. 3594853 Japanese Patent No. 5814487

In the case of manufacturing a fan-out wafer level package, semiconductor elements 104 that have already been separated into individual pieces are mounted on an adhesive layer 101 of a temporary fixing material in which an adhesive layer 103 is arranged on a substrate 102 ( 5A and 5B), and then the semiconductor element 104 is sealed with a sealing material 105 (see FIG. 5C). Therefore, after peeling the semiconductor element 104 from the adhesive layer 103, not only the back surface of the semiconductor element 104 but also the surface of the sealing material 105 are exposed at the same time (see FIG. 5D). Therefore, in order to protect those surfaces, it is necessary to further form a protective layer 106 after peeling the semiconductor element 104 from the adhesive layer 103, or to form a protective layer 106 for each individual package ( See FIG. 5(e)). After grinding the sealing material, a rewiring layer 107 is formed (see FIG. 5F).

However, separating from the adhesive layer and forming the protective layer separately is not preferable from the viewpoint of productivity, and it is necessary to further simplify the semiconductor device manufacturing process.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of manufacturing a semiconductor device that enables simplification of the semiconductor device manufacturing process.

As a result of intensive studies, the inventors of the present invention found a method of manufacturing a semiconductor device capable of solving the above problems, and completed the present invention. That is, the present invention is characterized by having the following aspects.

[Claim 1] A semiconductor element is mounted on the resin layer of a film in which a resin layer and a base material that can be peeled off from the resin layer are integrated so that the bump surface faces upward. A method of manufacturing a semiconductor device.

[Claim 2] The method of manufacturing a semiconductor device according to Claim 1, wherein the semiconductor elements separated into individual pieces are mounted on the resin layer.

[Claim 3] The method of manufacturing a semiconductor device according to claim 1 or 2, wherein the resin layer has adhesiveness.

[Claim 4] The method according to any one of claims 1 to 3, characterized in that after the semiconductor element mounted on the resin layer is sealed with a sealing material, the base material is peeled off from the resin layer. A method of manufacturing the semiconductor device described.

[Claim 5] The semiconductor device according to any one of Claims 1 to 4, wherein after the base material is separated from the resin layer, the semiconductor device is singulated into one or a plurality of semiconductor device units. manufacturing method.

[Claim 6] The base material is a laminate in which two or more peelable metal foils are arranged on one side or both sides, and the metal foil is arranged at least on the side of the base material that is in contact with the resin layer. 6. The method of manufacturing a semiconductor device according to claim 1.

[Claim 7] The method of manufacturing a semiconductor device according to Claim 6, wherein one sheet of the metal foil is left on the resin layer when the base material is peeled off from the resin layer.

[8] The method of manufacturing a semiconductor device according to [6] or [7], wherein the portion of the laminate other than the metal foil is made of an organic material.

[9] The method of manufacturing a semiconductor device according to any one of [6] to [8], wherein the laminated body has a glass cloth.

[10] The method of manufacturing a semiconductor device according to any one of [6] to [9], wherein the laminated body has a glass transition point of 120°C to 300°C.

[Claim 11] A claim characterized in that the coefficient of thermal expansion below the glass transition point of the portion other than the metal foil of the laminate is 1×10 ^-6 /°C to 20×10 ^-6 /°C. 11. The method of manufacturing a semiconductor device according to any one of 6 to 10.

[Claim 12] The semiconductor device according to any one of Claims 6 to 11, wherein the thickness of the portion of the laminate other than the metal foil is 0.015 mm to 2.00 mm. Production method.

[13] The method of manufacturing a semiconductor device according to any one of [6] to [12], wherein a circuit is formed in advance on the metal foil in contact with the resin layer.

[14] The method of manufacturing a semiconductor device according to any one of [1] to [13], wherein an acrylic polymer containing glycidyl acrylate is used as the resin layer.

[15] The method of manufacturing a semiconductor device according to any one of [1] to [14], wherein the resin layer contains an epoxy resin, a phenol resin, a curing accelerator, and an inorganic filler.

[16] The method of manufacturing a semiconductor device according to any one of [1] to [15], wherein the resin layer contains a glass cloth.

According to the method of manufacturing a semiconductor device of the present invention, the semiconductor element is mounted on the resin layer of the film in which the resin layer and the base material that can be separated from the resin layer are integrated with the bump surface facing upward. , In order to seal the semiconductor element, even if the resin layer is peeled off from the base material, the back surface of the semiconductor element is protected in advance. A package manufacturing process can be implemented.

According to the present invention, it is possible to provide a method of manufacturing a semiconductor device that enables simplification of the semiconductor packaging process.

A semiconductor device obtained by the present invention is suitable for electronic devices such as smartphones and tablet terminals that are becoming increasingly sophisticated and multi-functional.

FIG. 10 is a cross-sectional view for explaining a method of manufacturing a semiconductor device using a film in which a resin layer and a base material that can be separated from the resin layer are integrated; 1(a) is a cross-sectional view of the film, FIG. 1(b) is a cross-sectional view showing a state in which a semiconductor element is mounted on the film, and FIG. 1(c) is a cross-sectional view showing a state in which the semiconductor element is sealed with a sealing material. FIG. 1(d) is a cross-sectional view showing a state in which the peelable base material is peeled off; FIG. FIG. 4 is a cross-sectional view showing a state in which solder bumps are mounted and separated into individual semiconductor devices; FIG. 11 is a cross-sectional view for explaining a method of manufacturing a semiconductor device when the peelable base material is a laminate having two or more peelable metal foils arranged on one side thereof; 2(a) is a cross-sectional view of the film, FIG. 2(b) is a cross-sectional view showing a state in which a semiconductor element is mounted on the film, and FIG. 2(c) is a cross-sectional view showing a state in which the semiconductor element is sealed with a sealing material. FIG. 2(d) is a cross-sectional view showing the state in which the peelable base material is peeled off; FIG. FIG. 4 is a cross-sectional view showing a state in which solder bumps are mounted and separated into individual semiconductor devices; FIG. 10 is a cross-sectional view for explaining a method of manufacturing a semiconductor device when a circuit is formed in advance on the metal foil on the side contacting the resin layer; 3(a) is a cross-sectional view of the film, FIG. 3(b) is a cross-sectional view showing a state in which a semiconductor element is mounted on the film, and FIG. 3(c) is a cross-sectional view showing a state in which the semiconductor element is sealed with a sealing material. FIG. 3(d) is a cross-sectional view showing a state in which the peelable base material is peeled off; FIG. FIG. 4 is a cross-sectional view showing a state in which solder bumps are mounted and separated into individual semiconductor devices; FIG. 10 is a cross-sectional view for explaining a method of manufacturing a semiconductor device using a film in which a resin layer and a base material that can be separated from the resin layer are integrated; FIG. 4(a) is a cross-sectional view of the film, FIG. 4(b) is a cross-sectional view showing a state where the semiconductor element is mounted on the film, and FIG. 4(c) is a semiconductor element sealed with a sealing material. A cross-sectional view showing a state in which the material is ground, FIG. 4D is a cross-sectional view showing a state in which a rewiring layer is formed and solder bumps are mounted, and FIG. FIG. 4F is a cross-sectional view showing a state in which semiconductor devices are separated into individual pieces; FIG. 10 is a cross-sectional view for explaining a method of manufacturing a semiconductor device in which peeling from an adhesive layer and formation of a protective layer are performed separately; 5(a) is a cross-sectional view of the film, FIG. 5(b) is a cross-sectional view showing a state in which a semiconductor element is mounted on the film, and FIG. 5(c) is a cross-sectional view showing a state in which the semiconductor element is sealed with a sealing material. FIG. 5(d) is a cross-sectional view showing the state in which the base material is peeled off, FIG. 5(e) is a cross-sectional view showing the state in which the sealing material is being ground, and FIG. 5(f) is a rewiring layer formed FIG. 3 is a cross-sectional view showing a state in which

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated in detail, referring drawings as needed. However, the present invention is not limited to the following embodiments. Also, the dimensional ratios of the drawings are not limited to the illustrated ratios. Further, in this specification, a numerical range indicated using "to" indicates a range including the numerical values before and after "to" as the minimum and maximum values, respectively.

In the method of manufacturing a semiconductor device according to this embodiment, a film 3 is used in which a resin layer 1 and a substrate 2 that can be separated from the resin layer 1 are integrated (see FIG. 1A). The shape and size of the film 3 are not particularly limited, and may be, for example, a wafer shape with a diameter of 12 inches or a panel shape of 600 mm×600 mm.

The resin layer 1 is not particularly limited, and any resin can be applied. , a curing accelerator and an inorganic filler are preferably used. As the resin layer 1, it is preferable to use a resin containing glass cloth, for example, in order to impart rigidity and low thermal expansion.

As the acrylic polymer containing glycidyl acrylate, conventionally known ones can be used without particular limitation.

As the resin containing epoxy resin, phenol resin, curing accelerator and inorganic filler, conventionally known resins can be suitably used without particular limitation.

Further, as the glass cloth, conventionally known ones can be used without particular limitation. In addition, the resin in that case is not particularly limited.

The peelable substrate 2 is not particularly limited, and any substrate having a peelable layer 5 that can be peeled off by a method such as mechanical peeling, laser peeling, UV peeling, or thermal peeling can be used (Fig. 1(a)). From the viewpoint that the peeling process is simple and the metal foil layer can be provided on the resin layer 1, it is preferable that the peeling layer 5 is a laminate in which two or more peelable metal foils 51 and 52 are arranged on one side or both sides ( See FIG. 2(a)). In this case, it is preferable to arrange the metal foils 51 and 52 at least on the side of the substrate 2 that is in contact with the resin layer 1 .

The two or more peelable metal foils 51 and 52 are not particularly limited.

At this time, the portion 4 of the laminate having the metal foils 51 and 52 other than the metal foils 51 and 52 is not particularly limited, and any material such as organic material, glass, silicon wafer, metal plate, etc. can be applied. However, organic materials are preferable because they are easy to control physical properties, are not easily cracked during the wafer level package manufacturing process, and are easy to process into various shapes.
The organic material is not particularly limited.

Further, it is preferable that the laminate having the metal foils 51 and 52 has a glass cloth in order to impart rigidity and low thermal expansion.

The glass cloth is not particularly limited.

The method for producing the peelable base material 2 is not particularly limited, but when using the above organic material, glass cloth, and metal foil, the following steps can be performed. The conditions of each step can be arbitrarily set according to the resin to be applied.
(I) Impregnate a glass cloth with a varnish-like organic material using a coating machine, or laminate and impregnate a PET film with an organic material dam-coated from both sides of the glass cloth (II) Heat dry and B stage (half) (III) Two or more metal foils 51 and 52 that can be peeled off are placed on one or both sides of the material and pressed (IV) The organic material is cured.

Further, by setting the Tg (glass transition point) of the laminate having the metal foils 51 and 52 to 120° C. to 300° C., it is possible to ensure dimensional stability in the heating step during the wafer level package manufacturing process, which is preferable.

If the Tg is less than 120° C., it becomes a rubber region every time a drying step is performed during the wafer level package manufacturing process, which is not preferable because it tends to cause distortion inside the substrate. On the other hand, if the Tg exceeds 300° C., the temperature required for the curing reaction of the laminate itself tends to be high, and distortion tends to occur inside the substrate during curing of the laminate, which is not preferable.

Further, by setting the thermal expansion coefficient below Tg of the portion 4 other than the metal foils 51 and 52 of the laminate having the metal foils 51 and 52 to 1×10 ⁻⁶ /° C. to 20×10 ⁻⁶ /° C., This is preferable because warping when the semiconductor element 6 is mounted and sealed with the sealing material 8 can be easily suppressed. The sealing material 8 is not particularly limited, and any sealing resin suitable for the purpose of the semiconductor device can be applied. For example, an epoxy resin or the like containing silica having a diameter of about 5 to 20 μm in a range of 5 to 80 wt % can be applied. The thermal expansion coefficient of the semiconductor element 6 is around 3.5×10 ⁻⁶ /° C., and the sealing material 8 is around 5.0×10 ⁻⁶ /° C. to 25.0×10 ⁻⁶ /° C., When the coefficient of thermal expansion is within the above range, it is easy to optimize the size of the semiconductor element 6, the thickness of the encapsulant 8, and the like.

When the semiconductor element 6 is mounted and sealed with the sealing material 8, the thermal expansion coefficient below Tg of the portion other than the metal foils 51 and 52 of the laminate having the metal foils 51 and 52 is 1×10 ⁻⁶ / When the temperature is below 20×10 ⁻⁶ /° C., it tends to warp into a smile shape (a curved shape in which the sealing material 8 side is concave and the film 3 side is convex) with the sealing material 8 facing upward. It is preferable because it tends to warp into a cry shape (a curved shape in which the sealing material 8 side is convex and the film 3 side is concave) with the sealing material 8 facing upward, and it tends to interfere with the peeling process of the peelable base material 2. do not have.

In addition, by setting the thickness of the portion 4 other than the metal foils 51 and 52 of the laminate having the metal foils 51 and 52 to 0.015 mm to 2.00 mm, warping during the wafer level package manufacturing process and manufacturing It is preferable because it is compatible with ease of use.

If the thickness of the portion 4 other than the metal foils 51 and 52 of the laminate is less than 0.015 mm, the rigidity of the base material 2 that can be peeled off decreases, and it becomes difficult to keep the coefficient of thermal expansion low, which is not preferable. , 2.00 mm, it is not preferable because it becomes difficult for the conveying system of the apparatus and the sealing mold to cope with it, and the production cost of the peelable base material 2 increases.

In order to provide the resin layer 1 on the peelable base material 2, the resin layer 1 can be formed by any method such as lamination, spin coating, dam coating, die coating, pressing, etc., and the method is not particularly limited. .

For example, when an acrylic polymer containing glycidyl acrylate is used as the resin layer 1, the following steps can be taken. Conditions for each step can be arbitrarily set according to the resin to be applied.
(I) Dam-coating a varnish-like resin on a PET film (II) B-stage (semi-cured) by heating and drying (III) Laminating on a peelable substrate 2 (IV) Curing the resin

For example, when a resin containing glass cloth is used as the resin layer 1, the following steps can be performed. Conditions for each step can be arbitrarily set according to the resin to be applied.
(I) Impregnate a glass cloth with a varnish-like resin using a coating machine, or laminate and impregnate a PET film with a resin dam-coated from both sides of the glass cloth (II) B stage (semi-cured) by heating and drying (III) Pressing onto the peelable substrate 2 (IV) Curing the resin

The resin layer 1 may be maintained in a semi-cured state and have adhesiveness by adjusting heat drying, lamination, pressing, curing conditions, and the like in the above steps.

In addition, in the method of manufacturing a semiconductor device according to this embodiment, the semiconductor element 6 is mounted on the resin layer 1 (see FIGS. 1B and 2B). In this case, it is preferable to mount individualized semiconductor elements 6 on the resin layer 1 .

The number, size, thickness, material, attachments, functions, etc. of the semiconductor elements 6 are not particularly limited, and all kinds of semiconductor elements can be applied. Also, the method of mounting the semiconductor element 6 is not particularly limited, and any device and method such as a die bonder widely used in the post-process of semiconductors can be applied. The conditions for mounting the semiconductor element are not limited at all, and the temperature, pressure, application time thereof, and the like can be arbitrarily set.

Any type of adhesive, including a die bond film and an underfill material, can be used for bonding the semiconductor element 6. However, if the resin layer 1 has adhesiveness as described above, the supply of these adhesives will be difficult. This is preferable because it eliminates the need for a process and simplifies the process.

Further, in the method of manufacturing a semiconductor device according to the present embodiment, the semiconductor element 6 is mounted on the resin layer 1 so that the bump surface faces upward. The bump surface is the surface on which the bumps 7 of the semiconductor element 6 are formed. A sheet-like member may be applied to protect the bump surfaces of the semiconductor element during mounting, and a step of removing it later may be included.

Further, in the method for manufacturing a semiconductor device according to the present embodiment, after sealing the semiconductor element 6 mounted on the resin layer 1 with the sealing material 8 (see FIGS. 1(c) and 2(c)), the resin layer A peelable base material 2 is peeled off from 1 (see FIG. 1(d) and FIG. 2(d)). The sealing method is not particularly limited, and any method such as a compression mold method, a transfer mold method, a film lamination method, or a dispensing method can be applied under arbitrary sealing conditions.

In addition, in the method of manufacturing a semiconductor device according to the present embodiment, after peeling off the peelable base material 2, after passing through a desired assembly process if necessary, the semiconductor device is singulated into one or a plurality of semiconductor device units. (See FIG. 1(e) and FIG. 2(e)). The applicable assembly process is not particularly limited, but includes grinding of the sealing material 8, formation of the rewiring layer 9, mounting of the solder bumps 10, and formation of the conductive vias 11 in the sealing material 8 (FIG. 3 ( e) see) and the like. Dividing into semiconductor device units can be performed using various devices including a dicer (dicing machine), and is not particularly limited.

At this time, when a laminate having two or more peelable metal foils 51 and 52 is used as the peelable base material 2 , if one sheet of the metal foil 51 is left on the resin layer 1 , the semiconductor element 6 will be damaged. Since the metal foil 51 remains on the back surface through the resin layer 1, the heat generated by the semiconductor element 6 can easily escape to the outside of the package, which is preferable (see FIGS. 2(d) and 2(e)).

Furthermore, by forming a circuit 53 in advance on the metal foil 51 on the side that contacts the resin layer 1, the surface of the resin layer 1 can be applied as a circuit surface similar to the substrate, which is preferable (FIGS. 3A to 3D). e) see). A method of forming the circuit 53 is not particularly limited, and any method such as a subtractive method, a semi-additive method, or an additive method can be used. In FIG. 3(e), after peeling off the peelable base material 2, the sealing material 8 is ground, the conductive vias 11 are formed in the sealing material 8, the rewiring layer 9 is formed, the solder bumps 10 are mounted, A state in which singulation is performed is shown. By forming the circuit 53 on the metal foil 51 in advance, a semiconductor device with higher functionality can be manufactured.

The timing of peeling off the peelable material is not particularly limited. For example, as shown in FIGS. 4(a) to 4(f), the sealing material 8 is ground (see FIG. 4(c)), the rewiring layer 9 is formed, and the solder bumps 10 are mounted (see FIG. 4 ( d)) may be carried out, after which the peelable base material 2 may be peeled off (see FIG. 4(e)) and separated into individual semiconductor devices (see FIG. 4(f)).

As described above, according to the present invention, it is no longer necessary to separate the separation from the adhesive layer and the formation of the protective layer, thereby simplifying the semiconductor device manufacturing process. The semiconductor device is suitable for a thin and highly functional semiconductor device, and has a very large industrial utility value.

DESCRIPTION OF SYMBOLS 1... Resin layer, 2... Base material, 3... Film, 4... Part other than metal foil of laminated body, 5... Release layer, 6... Semiconductor element, 7... Bump, 8... Sealing material, 9... Rewiring layer , 10... Solder bump 11... Conductive via 51, 52... Metal foil 53... Circuit 101... Adhesive layer 102... Base material 103... Adhesive layer 104... Semiconductor element 105... Sealing material 106... Protective layer, 107... Rewiring layer.

Claims (14)

A semiconductor element is mounted on the resin layer of a film in which a resin layer and a base material that can be separated from the resin layer are integrated with the bump surface facing upward,
After sealing the semiconductor element mounted on the resin layer with a sealing material, the base material is peeled off from the resin layer, and then the sealing material is ground ,
A method of manufacturing a semiconductor device, wherein an acrylic polymer containing glycidyl acrylate is used as the resin layer . 2. The method of manufacturing a semiconductor device according to claim 1, wherein the semiconductor elements separated into individual pieces are mounted on the resin layer. 3. The method of manufacturing a semiconductor device according to claim 1, wherein said resin layer has adhesiveness. 4. The method of manufacturing a semiconductor device according to claim 1, wherein after the base material is separated from the resin layer, the substrate is separated into one or a plurality of semiconductor device units. The film has a laminate in which two or more peelable metal foils are arranged on one side or both sides of the base material,
5. The method of manufacturing a semiconductor device according to claim 1, wherein the metal foil is arranged at least on a side of the base material that is in contact with the resin layer. 6. The method of manufacturing a semiconductor device according to claim 5, wherein one sheet of the metal foil is left on the resin layer when the base material is peeled off from the resin layer. 7. The method of manufacturing a semiconductor device according to claim 5, wherein a portion of said laminate other than said metal foil is made of an organic material. 7. The method of manufacturing a semiconductor device according to claim 5, wherein said laminate comprises glass cloth. 9. The method of manufacturing a semiconductor device according to claim 5, wherein the laminated body has a glass transition point of 120.degree. C. to 300.degree. 10. The thermal expansion coefficient below the glass transition point of the portion other than the metal foil of the laminate is 1×10−6/° C. to 20×10−6/° C., according to any one of claims 5 to 9. 1. A method of manufacturing a semiconductor device according to claim 1. 11. The method of manufacturing a semiconductor device according to claim 5, wherein the thickness of the portion of the laminate other than the metal foil is 0.015 mm to 2.00 mm. 12. The method of manufacturing a semiconductor device according to claim 6, wherein a circuit is formed in advance on said metal foil in contact with said resin layer. 13. The method of manufacturing a semiconductor device according to claim 1 , wherein the resin layer contains an epoxy resin, a phenol resin, a curing accelerator and an inorganic filler. 14. The method of manufacturing a semiconductor device according to claim 1 , wherein the resin layer contains glass cloth.

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