JP2000260796A - Method for resin-coating semiconductor wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance productivity of a resin-coating wafer, when a mounting face of a bump of a semiconductor wafer is coated with a resin by the use of a resin-coating die (both upper and lower dies) for forming the resin coating wafer. SOLUTION: Semiconductor wafers 4 are supplied to a prescribed position in a lower die cavity 5 with setting a bump-mounting face as an upper face, and the required amount of a resin material 6 is supplied to the bump-mounting face, and also both dies 1, 2 are clamped, so that an open air intercepting range 34 containing at least the cavity 5 is evacuated to set at least the interior of the cavity 5 in a predetermined vacuum condition, and also the resin material is heated and fused. Next an upper die face stretching film 7 is abutted on the front end part of a bump 3, and also the bump-mounting face of the semiconductor wafer 4 in the cavity 5 is coated with resin, to form a resin-coating wafer 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a resin coating method for a semiconductor wafer in which a bump mounting surface of a semiconductor wafer on which, for example, solder bumps (protruding electrodes) are mounted is coated with resin.

[0002]

2. Description of the Related Art Conventionally, for example, it has been practiced to protect and reinforce soft and easily damaged bumps by coating a bump mounting surface of a semiconductor chip in a chip size package (CPS) or the like with a resin. The resin coating on the chip is performed at the semiconductor wafer stage (wafer level). For example, FIG.
First, using the resin-coated mold shown in (2), the bump mounting surface of the semiconductor wafer is resin-coated to form a resin-coated wafer, and then the resin-coated wafer is cut and separated into a large number of pieces. Forming a resin-coated chip has been performed.

That is, the mold shown in FIGS. 5A and 5B is provided with an upper die 81 and a lower die 82 opposed to each other. The lower die 82 includes a cavity 85 for supplying and setting a semiconductor wafer 84 on which the bumps 88 are mounted, and the cavity 85 for resin coating. A fitting hole 86 and a bottom member 87 including the bottom surface of the cavity 85 that slides up and down in the fitting hole 86 are provided. Therefore, FIG.
As shown in (1), first, the film 83 is stretched on the mold surface of the upper die 81, and the semiconductor wafer 84 is supplied and set in the cavity 85 with the bump mounting surface thereof facing upward. Then, a required amount of resin material 89 is supplied onto the bump mounting surface, and the upper and lower molds 81 and 82 are supplied.
And the resin material 89 in the cavity 85 is heated and melted. Next, as shown in FIG. 5B, in the cavity, the bottom member 87 is placed with the semiconductor wafer 84 placed on the bottom member 87.
Is moved upward so that the tip of the bump 88 abuts on the film 83. At this time, since at least the bump mounting surface of the wafer 84 is covered with the resin, the resin-coated surface (bump mounting surface) of the resin-coated wafer 90 formed in the cavity 85 has The portion (the tip of the bump) in contact with the film 83 is exposed on the resin surface.

[0004]

However, when the molten resin material penetrates into the gap (sliding portion) between the fitting hole and the bottom member and is hardened, the resin flash (cured material) enters the gap. This is likely to cause poor sliding on the bottom member. Therefore, it is necessary to frequently remove resin burrs generated in the gaps, and there is a problem that productivity of the resin-coated wafer is reduced. In addition, the occurrence of the sliding failure makes it impossible to apply sufficient resin pressure to the resin in the cavity with the bottom member, so that the bump cannot be brought into contact with the film, and In other words, there is a problem that it is impossible to obtain a high-quality and high-reliability resin-coated wafer (resin-coated chip).

Accordingly, an object of the present invention is to provide a resin coating method for a semiconductor wafer, which can improve the productivity of the resin-coated wafer. Also,
SUMMARY OF THE INVENTION An object of the present invention is to provide a resin coating method for a semiconductor wafer capable of obtaining a high quality and high reliability resin coated wafer.

[0006]

According to the present invention, there is provided a method for coating a resin on a semiconductor wafer, comprising the steps of: providing a resin for coating a bump mounting surface of a semiconductor wafer on which bumps are mounted; A semiconductor for placing and supplying the semiconductor wafer at a predetermined position on the bottom surface of the resin coating mold cavity provided on one mold surface of the mold, with the bump mounting surface being opposite to the mold cavity bottom surface. A wafer supplying step, a film extending step for extending a bump exposing film on the other mold surface of the mold, and a semiconductor wafer supplying step, wherein the wafer is sucked and fixed to the mold cavity bottom surface during the semiconductor wafer supplying step. Semiconductor wafers
A fixing step, a film sucking / fixing step of sucking / fixing the film to the other mold surface of the mold during the film stretching step, and a resin for supplying a required amount of resin material into the mold cavity. A material supplying step, a mold clamping step of clamping the mold, a heat melting step of a resin material for heating and melting the resin material in the mold cavity, and the other of the molds. A pressing step of pressing the film in the direction of the mold cavity with a pressing member provided on a mold surface; and, during the pressing step of the pressing member, contacting the film with the tip of the bump in the mold cavity. During the contacting step of the film and the pressing step by the pressing member, the bump mounting surface of the semiconductor wafer is pressed by pressing the resin in the mold cavity through the film. A resin-coated molding step of a semiconductor wafer to be coated with a resin, and a mold release of the resin-coated semiconductor wafer in which the mold is opened and the resin-coated semiconductor wafer in which the bump mounting surface is coated with the resin from within the mold cavity is released. And a process.

In addition, the method for coating a resin on a semiconductor wafer according to the present invention for solving the above-mentioned technical problems is characterized in that at least the inside of the mold cavity is evacuated to a predetermined vacuum during the mold clamping step. It is characterized by being in a state.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, using a mold (both upper and lower dies) for resin coating of a semiconductor wafer, first, the semiconductor wafer is placed at a predetermined position in the lower mold cavity with its bump mounting surface facing upward. Supplying and supplying a required amount of the resin material onto the bump mounting surface, and clamping the two dies, thereby evacuating at least the inside of the cavity by evacuating the outside air blocking range including at least the cavity. And the resin material is heated and melted. Then, the upper mold surface covering film 7 is brought into contact with the tip of the bump, and the bump mounting surface of the semiconductor wafer is filled with resin in the cavity. Coating to form a resin coated wafer.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings.

[0010] That is, the mold shown in FIG.
And a movable lower mold 2 disposed opposite to the fixed upper mold 1. In addition, a bump projection electrode 3 is provided on the mold surface of the lower mold 2.
A resin coating cavity 5 is provided for supplying and setting the semiconductor wafer 4 on which the bumps are mounted with the bump mounting surface facing upward (mold surface side), and is mounted at a predetermined position on the bottom surface of the cavity 5. It is configured such that a required amount of, for example, a powdery or granular resin material 6 can be supplied onto the bump mounting surface of the wafer 4 supplied and supplied. A film 7 (release film) for exposing bumps is stretched on the mold surface of the upper die 1 and
A pressing member 8 having a pressing surface (upper die surface) corresponding to the shape of the lower die surface of the lower die cavity 5;
And an up-down movement mechanism 9 for moving up and down. Therefore, by moving the pressing member 8 downward by the vertical movement mechanism 9, the tip of the bump 3 can be brought into contact with the film 7, and the resin in the cavity 5 is removed. It is configured such that it can be pressed with a predetermined resin pressure through the film 7.
A locking member 10 (annular projection) for locking and fixing the film 7 to the mold surface is provided around the outer periphery of the cavity 5 (lower mold surface).・ 2
Further, the film 7 is configured to be sandwiched and fixed between the two mold surfaces and stretched on the lower mold cavity surface. Although not shown, the mold is provided with a heating means for heating up to the resin molding temperature, and heats and melts the resin material 6 supplied into the cavity 5. It is configured to be able to.

As shown in the figure, the bottom surface of the mold cavity 5 is provided with a semiconductor wafer suction fixing means (for example, a required number of suction holes) for sucking and fixing the semiconductor wafer 4 on the bottom surface of the mold cavity 5. ) 31 are provided. Therefore, when the semiconductor wafer 4 is placed and supplied in the mold cavity 5, the semiconductor wafer 4 is evacuated from the suction hole 31 on the bottom surface of the mold cavity 5 so that the semiconductor wafer 4 is placed on the bottom surface of the mold cavity 5. It can be adsorbed and fixed at a predetermined position.

As shown in the drawing, a locking member 10 provided around the cavity 5 on the lower mold surface is provided.
At a predetermined position on the upper and lower mold surfaces corresponding to the outer periphery of the film, there is provided a fixing member for the film, which clamps the film 7 and fixes the film 7 between the mold surfaces when the molds 1 and 2 are clamped. In addition, the fixing member includes an annular convex portion 32 provided on a lower mold surface and a lower annular convex portion 32 provided on an upper mold surface.
And a suction / discharge mechanism 35 provided in the recess 33. Therefore, the suction / discharge mechanism 35
Thus, the film 7 can be suction-fixed to the upper mold surface by forcibly sucking and discharging air or the like. When the molds 1 and 2 are clamped, the annular convex portion 32 and the annular concave portion 33 of the fixing member are fitted to each other, and the suction / discharge mechanism 35 is inserted from the upper annular concave portion 33.
By forcibly sucking and discharging air or the like to draw and stretch the film 7 into the concave portion 33, the wrinkles of the film 7 can be stretched and removed. Further, a configuration in which one or a plurality of the above-described film fixing members (combinations of the above-described concave portions 33 and convex portions 32) are provided can be adopted.

Further, the above-mentioned mold has a vacuuming mechanism (shown in the drawing) for evacuating at least a molding portion including the mold cavity 5 from an outside air blocking range 34 including at least the molding portion. None) is provided, and the vacuum section is evacuated from the outside air cutoff area 35 by the evacuation mechanism so that at least the molded portion including the cavity 5 can be brought into a predetermined vacuum state.

That is, first, the film 7 is stretched on the mold surface of the upper mold 1 and the suction and discharge mechanism 35 is forcibly sucking and discharging air or the like from the annular recess 33 of the upper mold 1. Thereby, the film 7 can be efficiently sucked and fixed to the upper mold surface. Next, the semiconductor wafer 4 is supplied and set at a predetermined position on the bottom surface in the lower mold cavity 5 with the mounting surface of the bump 3 facing upward, and the resin material 6 is required on the bump mounting surface. Supply quantity. At this time, the semiconductor wafer 4 can be efficiently suctioned and fixed to the bottom surface of the cavity 5 by the suction fixing means 31. Next, the lower mold 2 is moved upward to perform an intermediate mold clamping for holding the space between the two mold surfaces at a required interval, and at least the molded portion including the cavity 5 is set in an outside air blocking state to set an outside air blocking range 34. Then, the inside of the cavity 5 (the outside air blocking range 34) is brought into a predetermined vacuum state by evacuating the outside air blocking range 34 by the vacuuming mechanism. Next, the lower die 2 is moved upward to completely close the die for joining the two die surfaces, and the convex part and the concave part of the fixing member are fitted. At this time, the film 7 is locked between the two mold surfaces by the locking member 10, and the film 7 is drawn into the concave portion 32 and the film 7 is stretched. 7 can be efficiently removed by smoothing the wrinkles. Next, the resin material 6 supplied into the cavity 5 is heated and melted. Then, the film 7 is moved into the cavity 5 by moving the pressing member 8 (the pressing surface) down (in the direction below the lower mold surface in the cavity 5) by the vertical movement mechanism 9. By pressing and extending, the film 7 comes into contact with the tip of the bump 3, and the resin in the cavity 5 is pressed by the pressing member 8 at a predetermined resin pressure via the film 7. At this time, the film 7 can be configured so that at least the tip of the bump 3 is not in contact with the resin. At this time, the film 7
In addition, the wrinkles of the film generated in the cavity 5 can be extended and removed, and the resin can be sealed in the cavity 5 by sealing the inside of the cavity 5 with the film 7. After the required time for curing has elapsed, the molds 1 and 2 can be opened, and the resin-coated wafer 12 can be released between the molds with the film 12 adhered to the film 7. That is, the resin-coated wafer 12 can be formed in a state in which the tip of the bump 3 mounted on the wafer 4 is exposed on the surface of the resin 11.
Eliminating the adverse effects shown in the conventional example, it is possible to improve the productivity of resin-coated wafers,
A highly reliable resin-coated wafer can be obtained. In addition, since the molded part including at least the cavity 5 can be coated with a resin in a predetermined vacuum state, the resin 1 covering the mounting surface of the semiconductor wafer 4 with the bumps 3 can be formed.
In this case, bubbles (voids) and defective portions generated in 1 can be efficiently prevented.

In the above-described embodiment, the fixing member (the concave portion 33 and the convex portion 32 and the suction / discharge mechanism 3 described above) may be used.
In the case of a configuration in which a plurality of 5) are provided, at the time of the mold clamping of the above-mentioned two dies, substantially simultaneously from inside the concave portion 32, individually, or sequentially from the outer concave portion 32, or arbitrarily. In addition, it is possible to employ a structure in which the film 7 is forcibly sucked and discharged to draw the film 7 into the concave portion 32 and stretched to extend the wrinkles of the film 7.

Further, it is possible to adopt a structure in which the lower mold 2 is continuously moved upward during the intermediate mold clamping in the above-described embodiment.

The resin-coated wafer 12 shown in FIGS. 4 (1) and 4 (2) is cut and separated into chips 13 shown in FIG. 4 (2), and the resin-coated chips 14 shown in FIG. Is formed, and the tip of the bump 3 exposed on the surface of the resin 11 of the resin-coated chip 14 can be electrically connected to, for example, a substrate or the like.

Further, in the above-described embodiment, a configuration in which a single cavity is provided in the mold is illustrated. However, a configuration in which a plurality of cavities are provided in the mold may be employed.

Further, in the above-described embodiment, a configuration using a powdery or granular resin material has been exemplified, but various shapes of resin materials such as a resin tablet can be used. Further, in the above-described embodiment, the configuration using the thermosetting resin material is exemplified. However, for example, a thermoplastic resin material or the like can be adopted.

The present invention is not limited to the above-described embodiments, but may be arbitrarily and appropriately changed and selected as necessary without departing from the spirit of the present invention. is there.

[0021]

According to the present invention, there is provided an excellent effect that it is possible to provide a resin coating method for a semiconductor wafer which can improve the productivity of a resin-coated wafer.

Further, according to the present invention, there is provided an excellent effect that a resin coating method for a semiconductor wafer capable of obtaining a resin coated wafer of high quality and high reliability can be provided.

[Brief description of the drawings]

FIGS. 1 (1) and 1 (2) are schematic longitudinal sectional views schematically showing a resin-coated mold for a semiconductor wafer according to the present invention, and FIG. 1 (1) shows a semiconductor wafer and a film. FIG. 1 (2) shows the state of suction and fixation of the semiconductor wafer described above.

FIGS. 2 (1) and 2 (2) are schematic longitudinal sectional views schematically showing a resin-coated mold for a semiconductor wafer according to the present invention, and FIG. FIG. 2 (2) shows a state where the air is evacuated from the outside air blocking range formed in the mold as described above.

3 (1) and 3 (2) are schematic longitudinal sectional views schematically showing a resin-coated mold of a semiconductor wafer according to the present invention, and FIG. 3 (1) is a bump of the semiconductor wafer. FIG. 3B shows a state in which the film is in contact with the leading end, and FIG. 3B shows a state in which the mold is opened and the resin-coated wafer is released.

FIG. 4 (1) is a partially cutaway schematic side view schematically showing a resin-coated wafer, and FIG. 4 (2) is a schematic bottom view of the resin-coated wafer shown in FIG. 4 (1); FIG. 4 (3)
FIG. 2 is a schematic longitudinal sectional view schematically showing a resin-coated chip formed by cutting and separating the resin-coated wafer.

5 (1) and 5 (2) are schematic longitudinal sectional views schematically showing a conventional resin-coated mold.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 fixed upper mold 2 movable lower mold 3 bump 4 semiconductor wafer 5 cavity 6 resin material 7 film 8 pressing member 9 vertical movement mechanism 10 locking member 11 resin 12 resin-coated wafer 13 chip 14 resin-coated chip 31 semiconductor wafer suction fixing means 32 annular convex part 33 annular concave part 34 outside air blocking range 35 suction / discharge mechanism

Continued on front page F-term (reference) 4F204 AC01 AC04 AD02 AD05 AG03 AH33 AM28 AM33 FA01 FB01 FB12 FB20 FB23 FB24 FE06 FE27 FF01 FF05 FF23 FF50 FG02 FG07 FH06 FJ30 FN11 FN12 FN15 FN20 5F061 AA01 DD01

Claims (2)

[Claims] The semiconductor wafer is provided at a predetermined position on the bottom surface of a resin coating mold cavity provided on one mold surface of a resin coating mold for coating a bump mounting surface of a semiconductor wafer having a bump mounted thereon with a resin. A step of supplying a semiconductor wafer to be placed and placed in a state in which the bump mounting surface is on the opposite side to the bottom surface of the mold cavity; and a film stretching step of stretching a bump exposing film on the other mold surface of the mold. Setting step, at the time of supplying the semiconductor wafer, attraction and fixing step of the semiconductor wafer to attract and fix the wafer to the bottom surface of the mold cavity, at the time of stretching the film, the other mold surface of the mold A film sucking and fixing step of sucking and fixing the film, a resin material supplying step of supplying a required amount of resin material into the mold cavity, and clamping the mold. A mold-clamping step, a heat-melting step of the resin material for heating and melting the resin material in the mold cavity, and pressing the film with the pressing member provided on the other mold surface of the mold. A pressing step by a pressing member that presses in a cavity direction; a pressing step by the pressing member; a film contacting step of contacting the film with the bump tip in the mold cavity; and a pressing step by the pressing member. A resin coating molding process for a semiconductor wafer in which the resin in the mold cavity is coated with the resin by pressing the resin in the mold cavity through the film; and the mold is opened by opening the mold. A resin-coated wafer releasing step of releasing a resin-coated semiconductor wafer having the bump mounting surface coated with resin from inside a mold cavity. Resin coating method for a semiconductor wafer. 2. The method according to claim 1, wherein at least the inside of the mold cavity is evacuated to a predetermined vacuum state during the mold clamping step.