JP2002145380A - Wafer packing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a dicing tape from peeling off from a dicing frame. SOLUTION: When packing members 28, each having a wafer 12 with a dicing frame 20 which is a mounting frame, are stacked on one another to be stored in a packing box 24, the dicing frame is fixed between the wafers to be vertically stacked on each other, and a hollow disc-like cushioning material 30 for separating the upper and the lower wafers from each other is inserted therebetween. Since the upper and the lower dicing frames can be stacked on each other without leaving a gap with the aid of the cushioning material, an excessive force is not applied to the dicing frames even in the case where a shock and a vibration are applied to the dicing frames during transport. As a result, since such an excessive force as to peel off dicing tapes from the dicing frames is not applied to the dicing frames, part of the dicing tapes is not unexpectedly peeled off from the dicing frames.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for packing a wafer. Specifically, the tape to which the wafer is attached is held by a frame, and when a packing member having this frame is stacked in a packing box, by stacking through a cushioning material, the impact during transportation etc. This prevents the tape from peeling off from the frame.

[0002]

2. Description of the Related Art In the production of semiconductor devices, production bases have been increasingly dispersed. In particular, a production base for wafers (semiconductor wafers such as silicon wafers) and a semiconductor chip (LSI chip, etc.) divided from this wafer have been developed. There is a strong tendency to specialize in assembly bases that assemble and package.

[0003] Therefore, in order to transport a wafer manufactured at a manufacturing base to a base for assembling and packaging, it is necessary to pack the wafer so that it can be shipped. When the wafer is sold to another manufacturer, it is necessary to pack it for shipping.

[0004] As the shipping form from the wafer manufacturing base, there are a case where the wafer is shipped as it is without being cut for each chip, and a case where the wafer is shipped as a divided wafer diced for each chip. Recently, the number of wafers shipped as divided wafers has increased.

[0005] In order to ship and transport the divided wafers as described above, there have conventionally been the following types of packing. As shown in FIG. 4, the divided wafer 12 is diced like a grid, and the disc-shaped divided wafer 12 is also disc-shaped.
Dicing tape 1 larger in diameter than wafer 12
4 and packed.

Prior to packing, the dicing tape 1
4 uses an inner ring 16 and an outer ring 18 as shown in FIG. 6, and a part of its peripheral surface is sandwiched from its front and back surfaces. At this time, the dicing tape 14 is sandwiched so as to be stretched in a tensioned state.

Further, outside the outer ring 18,
Similarly, a ring-shaped dicing frame 20 is provided,
Dicing tape 14 is provided on the lower surface of dicing frame 20.
Is bonded, and the dicing tape 14 and the dicing frame 20 are integrated. The dicing tape 14 is held in the shape shown in the figure by the tension. Divided wafer 12 with this dicing frame 20
Is hereinafter referred to as a packing member 28.

The packing member 28 integrated in this way is packed in a box as a packing unit. This is shown in FIG. As shown in FIG. 7, a plurality of divided wafers 12, 12,.
Are stacked via the protection sheet 22. Packing box 2
Reference numeral 4 denotes a box-shaped resin molded product or a cardboard box having the same inner size as the outer diameter of the dicing frame 20. By using such an inner-sized packing box 24, a plurality of divided wafers 12 can be transported to a destination (a factory or a request destination) without a box shift.

[0009]

As shown in FIG. 6, the outer peripheral edge 14a of the dicing tape 14 is packed in a state of being adhered to the dicing frame 20, and then loaded into a container or the like to reach the destination. Although transported, a truck or the like is often used as a transport means of the packing box 24, so during transportation until reaching the destination,
The divided wafers 12 stored in the packing box 24 receive various shocks and vibrations.

When such a shock or vibration is applied to the packing member 28, the dicing tape 14 may peel off from the dicing frame 20. This is mainly due to the following reasons.

As shown in FIG. 6, the dicing frame 20 to which the dicing tape 14 is attached is formed to be much thinner than the inner and outer holding rings 16 and 18. The thickness of the inner and outer holding rings 16 and 18 is about 6 mm, while the thickness of the dicing frame 20 is 1 mm.
mm. This is because although not shown, when bonding a chip to a lead frame or a package, the bonding apparatus is equipped with a clamp means which is mounted and fixed together with the dicing frame 20 on the wafer mounting table. The thickness of the dicing frame 20 is reduced.

As described above, the thicknesses of the holding rings 16 and 18 and the dicing frame 20 are different. When the divided wafers 12, 12,... Are stacked on the basis of this difference in thickness, as shown in FIG.
The upper and lower dicing frames 20, 20,...
And a slight gap 26 is created between them.

With this gap 26, every time a shock or vibration is applied to the packing box 24, extra vertical vibration is applied to the dicing frame 20, and a force in a direction such that the dicing tape 14 is peeled off based on the vibration. Acts on the dicing tape 14. As a result, even if the dicing tape 14 is strongly adhered to the dicing frame 20, the dicing tape 14 is pulled in various directions,
As shown in FIG. 8, the outer peripheral edge 14a of the dicing tape 14
May be separated from the dicing frame 20.
In some cases, the outer peripheral edge 14a may be completely separated from the dicing frame 20.

Outer peripheral edge 14a of dicing tape 14
When the dicing frame 20 is peeled off, the dicing frame 20 cannot be properly placed on the above-described clamping means, or even if the
Cannot be firmly clamped, so that a chip may be picked up by a mount head provided in a bonding apparatus and may not be bonded to a lead frame or the like.

Accordingly, the present invention has been made to solve such a conventional problem, and particularly, a wafer package in which a dicing tape is prevented from peeling off a part of a dicing frame even when a shock or vibration is applied during transportation. A method and a wafer packing apparatus are proposed.

[0016]

In order to solve the above-mentioned problems, in the wafer packing method according to the present invention, when stacking the packing members to which the wafers are attached and storing them in the packing box, It is characterized in that the cushioning material is interposed between the packing members and stacked.

According to the present invention, when stacking and packing wafers having a dicing frame as a mounting frame, the dicing frame is fixed between the vertically stacked wafers and the wafers to separate the upper and lower wafers. Insert cushioning material.

Since the upper and lower dicing frames can be stacked without gaps by this cushioning material, no extra force is applied to the dicing frame even if a shock or vibration is applied to the dicing frame during transportation. As a result, since no extra force for peeling the dicing tape from the dicing frame is applied, part of the dicing tape does not accidentally peel from the dicing frame.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a case where an embodiment of a method for packing a wafer according to the present invention is applied to a wafer packing apparatus will be described in detail with reference to the drawings. FIG. 1 shows a usage form of a wafer packing apparatus 10 to which the present invention is applied. For convenience of explanation, description will be given from FIG. 2 and FIG.

In the present invention, when wafers are stacked and transported, a cushioning material is inserted between the stacked wafers. The cushioning member 30 has a hollow disk shape as shown in FIG. 2, and an example of its size is shown in FIG.

As shown in FIGS. 3A and 3B, the inner diameter of the cushioning material 30 is made substantially equal to the outer diameter of the outer ring 18 for holding the dicing tape 14. Its outer diameter is Fig. 3C
Is selected so as to be substantially equal to the outer diameter of the dicing frame 20 shown in FIG. The thickness W of the cushioning member 30 may be any thickness as long as it is greater than the thickness of the dicing tape 14 plus the thickness of the wafer 12. In other words, the thickness is selected such that when the wafers 12 are stacked with the buffer material 30 inserted, there is a gap such that the upper inner ring 16 does not contact the lower wafer 12.

For example, the thickness of each of the inner and outer holding rings 16 and 18 is 6 mm, the thickness of the dicing frame 20 is about 1 mm, and the dicing tape 14 is 80 to 1 mm.
When the thickness is about 00 μm, the thickness W of the cushioning material 30 may be selected to be about 6 to 10 mm.

As the cushioning material 30, a material that absorbs impact, has a certain degree of mechanical strength, does not generate dust, is lightweight, and is non-chargeable is optimal. Therefore, polypropylene resin or the like is suitable as the material of the cushioning material 30.

An embodiment of a wafer packing apparatus 10 to which the present invention is applied will be described with reference to FIG. Here, the wafer 12 attached to the dicing frame 20 is used. As the wafer 12, a single wafer itself before dicing and a divided wafer diced like a grid are used. Conceivable.

A preferred wafer for application to the present invention is a divided wafer. This is because, in the case of a divided wafer, the package member 28 described above can be mounted on the bonding apparatus and clamped, and the process can be directly transferred to the chip bonding step.

In FIG. 1, a packing box 24 whose inner size is substantially the same as the outer diameter of the dicing frame 20 is used. The cushioning member 30 also has the same outer diameter as the inner size of the packing box 24. A packing member 2 having a dicing frame 20 attached to a dicing tape 14 is provided in a packing box 24.
8 are stored.

That is, the packaging member 28 affixed to the dicing frame 20 in a state where the divided wafer 12 is affixed to the dicing tape 14 and the dicing tape 14 is further stretched by the inner and outer holding rings 16 and 18. Is stored. The inner and outer retaining rings 16 and 18 may be made of resin or metal.

The first packing member 28A in which the dicing frame 20 and the divided wafers 12 are integrated is housed in the packing box 24. On the upper surface thereof, the second material is provided via the cushioning material 30 and the protective cover 22 described above.
Is stored. Since the cushioning material 30 is configured as shown in FIGS. 2 and 3, when the cushioning material 30 is stored in the packing box 24, its lower surface is in contact with the dicing frame 20, and its inner peripheral surface is formed on the outer holding ring 18. Is in contact with the outer peripheral surface of. Of course, the cushioning material 30 is stored in a state where the cushioning material 30 is in contact with the inner wall surface of the packing box 24 without any gap.

In this state, the second packing member 28B is stored on the upper surface of the cushioning material 30, but since the cushioning material 30 is interposed, the dicing frames 20, 20 located above and below the cushioning material 30 are The cushioning members 30 come into close contact with each other without any gap. In addition, the second
Does not come into contact with the first packing member 28A.

As described above, a plurality of packing members 28C, 28D,... Are sequentially stacked until a predetermined number is reached with the cushioning material 30 interposed therebetween. When the last packing member 28N is stored, the cover 32 is inserted. Closed. Cover 32
As long as the cover has a cushioning effect, a cover having an antistatic function is more preferable.

By using the above-mentioned cushioning material 30, the upper and lower dicing frames 20, 20,...
Even if an external shock or vibration is transmitted to the inside of the packing box 24, the shock can be absorbed by the cushioning material 30, and the dicing frame 20 is in close contact with the cushioning material 30 and there is almost no extra gap. So dicing frame 2
An extra force such that the dicing tape 14 is peeled from zero is not applied to both the dicing frame 20 and the dicing tape 14.

As a result, there is no danger that the outer peripheral edge portion 14a of the dicing tape 14 will be separated from the dicing frame 12, so that the dicing tape 14 is mounted on a mounting table provided in a bonding apparatus used for assembling chips. However, the dicing frame 20 can be correctly clamped. As a result, operation errors such as chip mounting failure can be greatly improved.

In the above-described embodiment, as shown in FIG. 3A, the inner surface of the cushioning member 30 having no step is used. However, as shown in FIG. The inner diameter may have a step 34 so as to overlap.

In this case, when packing, not only the dicing frame 20 but also the outer holding ring 18 can be fixed with the cushioning material 30 by the cushioning material 30, so that the packaging becomes more stable and measures against impact during transportation can be taken. Be perfect.

In the above embodiment, the wafer 1
Although a divided wafer is illustrated as the example 2, the present invention can be applied to a packing member in which the undivided wafer is attached to a dicing tape.

[0036]

As described above, in the wafer packing method according to the present invention, when a packing member is constituted by a wafer, a dicing tape for bonding the wafer, and a dicing frame to which the dicing tape is attached, the dicing frame is fixed. The packing member is packed using a cushioning material that can be used.

According to this, since the dicing frame can be stably stored in the packing box by the cushioning material without play, even if an external shock or vibration is applied to the packing box during the transportation of the wafer, the dicing frame is applied to the dicing frame. There is no danger that the attached dicing tape will peel off. As a result, the outer peripheral edge of the dicing tape is not turned up, so that when a divided wafer is used, the mounting of the dicing frame on the bonding apparatus becomes smooth and a stable bonding process can be realized.

Therefore, the wafer packing method according to the present invention is extremely suitable for application when packing and transporting divided wafers and the like.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing an embodiment of a wafer packing device according to the present invention.

FIG. 2 is a perspective view of a cushioning material according to the embodiment.

FIG. 3 is a cross-sectional view showing a relationship between a cushioning material, a ring, and a dicing frame.

FIG. 4 is a plan view showing a relationship between a divided wafer and a dicing tape.

FIG. 5 is a sectional view thereof.

FIG. 6 is a cross-sectional view showing a relationship among a divided wafer, a holding ring, and a dicing frame.

FIG. 7 is a cross-sectional view of a state where the packing member is stored in a box.

FIG. 8 is a diagram illustrating a peeling state of an outer peripheral edge portion of a dicing tape which may occur during transportation.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Wafer packing apparatus, 12 ... Divided wafer, 14 ... Dicing tape, 16, 18 ...
Retaining ring, 20 ... Dicing frame, 22 ...
・ Protection sheet, 24 ・ ・ ・ Packing box, 26 ・ ・ ・ Gap, 2
8A, 28B, packing material, 30 cushioning material

Claims (5)

[Claims] 1. A wafer packing method comprising: stacking packing members having wafers mounted thereon and storing the stacked packing members in a packing box, with a cushioning material interposed between the packing members. 2. The packaging member comprises a tape to which the wafer is adhered, inner and outer holding rings for fixing an outer peripheral surface of the tape, and a frame for adhesively fixing an outer peripheral edge of the tape. The method for packing a wafer according to claim 1, wherein: 3. The buffer material according to claim 2, wherein the cushioning material is a hollow disk and has a thickness such that upper and lower wafers do not come into contact with each other when they come into contact with the frames to be stacked. Wafer packing method as described. 4. The wafer packing method according to claim 2, wherein the tape and the frame are a dicing tape and a dicing frame used when bonding the wafer. 5. The method according to claim 1, wherein the wafer is a divided wafer.