JPH05228873A - Vacuum chuck - Google Patents

Abstract

PURPOSE:To attract a lot of chips arranged on a wafer so surely without disarraying their arrangement. CONSTITUTION:In a vacuum chuck suitable for suction of a semiconductor chip, an opening 10 and an air suction port 9 are installed in a box body 2 forming an empty space inside, and many capillaries 3 are fixed to the opening 10 parallelly and tightly. At that time, an air flowing port 11 at one end side of each capillary 3 is set up in the empty space 8, and a suction port at the other end side is projectingly set up outward from the box body 2. In succession, a flushed suction surface S is formed in the suction port of each capillary 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum chuck used for sucking a plurality of semiconductor chips (hereinafter simply referred to as chips) arranged on a wafer.

[0002]

2. Description of the Related Art Conventionally, as this type of vacuum chuck,
A so-called porous type in which air is sucked through a large number of pores is known, and one of them is a sintering type. For this sintering type vacuum chuck, for example, a porous material obtained by compression-molding powder of ceramic, metal, cemented carbide or the like and then heat-treating at high temperature is used.

FIG. 4 shows a conventional sintering type vacuum chuck. In the illustrated vacuum chuck 50, a porous material 52 is fitted into a concave portion provided in a box 51, and the porous material 52 is provided. Are arranged adjacent to the empty chamber 53 inside the box 51. In addition, above the box 51,
An air suction port 54 that communicates with the empty chamber 53 is provided.

A conventional vacuum chuck 50 having the above structure.
At, when a hose connected to a vacuum pump (not shown) is connected to the air suction port 54 and the vacuum pump is operated, the air around the chuck is sucked through the porous material 52 and the empty chamber 53. The suction force of the air at this time causes the chips 56 on the wafer 55 to move to the vacuum chuck 50.
Is adsorbed on the adsorption surface S of.

[0005]

However, in the above-mentioned conventional vacuum chuck 50, the porosity of the porous material 52 (the ratio of the volume occupied by the air in the total volume of the substance) is stabilized and the air permeability is uniform. Was very difficult to get.
Further, since the sintered particles cause fine irregularities on the adsorption surface S, the chips may be scratched during adsorption. Furthermore, the following problems also occur when the chip is actually adsorbed. That is, as shown in FIG. 4, when a plurality of chips 56 arranged on the wafer 55 are adsorbed, the air around the chuck flows obliquely upward near the outer edge of the porous material 52 as indicated by the arrow (broken line). Therefore, there is a problem in that the chip 56 located near the outer edge is adsorbed, but the chip 56 located in the central portion is not adsorbed. There is also a problem that the chips 56 are laterally displaced by the wind pressure of the lateral air flowing between the peripheral edge 57 of the box 51 and the wafer 55, and the arrangement of the chips 56 is disturbed.

As a measure for improving the above-mentioned problem, for example, as shown in FIG. 5, the porous material 52 and the peripheral edge portion 57 are divided according to the chip arrangement to reduce the width of each, and further, the lower end of the peripheral edge portion 57 is divided. A method of cutting off diagonally is possible. However, in this method, when the porous material 52 is fixed with an adhesive, the pores of the porous material 52 are blocked with the adhesive, so that the uniform air permeability of the chuck itself is significantly impaired. Another problem arises.

The present invention has been made to solve the above problems, and it is an object of the present invention to provide a vacuum chuck capable of reliably sucking a plurality of chips arranged on a wafer without disturbing the arrangement. To aim.

[0008]

The present invention has been made in order to achieve the above-mentioned object, and forms an empty chamber inside and has an air suction port and an opening communicating with the empty chamber. And a plurality of thin tubes fixed in parallel and in close contact with the opening of the box,
Each of these thin tubes is arranged in the empty space of the box with one end side as an air flow port, and is arranged so as to project outward from the box body with the other end side as a suction port and has a suction surface flush with the suction ports. The formed vacuum chuck.

[0009]

In the vacuum chuck of the present invention, when air is sucked from the air suction port provided in the box, the air around the chuck is sucked from the suction port of each thin tube through the air circulation port. At this time, air is uniformly sucked through the respective suction ports due to the air resistance generated in each thin tube. Therefore, a uniform suction force is generated on the entire suction surface of the chuck formed flush with each other, and the directionality of the suction force is unified by fixing the thin tubes in parallel. Further, since the chucking surface of the chuck is formed flush, the chip is not scratched during the chucking. In addition, since the part corresponding to the peripheral edge of the conventional vacuum chuck is composed only of the wall thickness of the thin tube, the air wrapping around the chuck is improved and the wind pressure of the air from the lateral direction on the wafer is reduced. To be done.

[0010]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 is a vertical sectional view showing an embodiment of a vacuum chuck according to the present invention, FIG. 2 is a view taken in the direction of arrow A in FIG. 1, and FIG.
3 is a perspective view of a main part of the vacuum chuck shown in FIG. As shown in the figure, the vacuum chuck 1 of this embodiment is roughly composed of a box body 2 and a large number of thin tubes 3.

First, the box 2 is composed of, for example, a flat plate-shaped upper lid 4 and a lower frame 6 having a substantially concave cross section and provided with a flange 5 at its end. The upper lid 4 and the lower frame 6 are fixed to each other by bolts 7, whereby an empty chamber 8 is formed inside the box 2. Furthermore, one upper lid 4 is provided so as to communicate with the vacant chamber 8.
An air suction port 9 is provided on the other side, and a substantially rectangular opening 10 is provided on the other lower frame 6.

On the other hand, the thin tube 3 is, for example, a straight tube and has an air flow port 11 at one end and an adsorption port 12 at the other end. Here, the air flow port 11 of the thin tube 3 is formed by cutting one end side of the pipe obliquely with respect to the axial direction, and the suction port 12 has the other end side substantially perpendicular to the axial direction. It is formed by cutting into. At that time, the lengths of the individual thin tubes 3 are cut so as to have substantially the same dimensions. Further, as the size of the thin tube 3, it is necessary to adopt a tube having an extremely small inner and outer diameter according to the width (about 0.2 mm) of the tip to be adsorbed. Here, as an example, the outer diameter is 0.41 mm and the inner diameter is 0.1
A 9 mm one was adopted.

In the description of the above embodiment, the box 2 is composed of the upper lid 4 and the lower frame 6, but the present invention is not limited to this, and the box 2 may be integrally formed by molding or the like. Is also possible.

Further, as the thin tube 3 according to this embodiment, a thin tube made of, for example, hard stainless steel is preferable in consideration of the influence on the quality of the product, the manufacturing cost of the chuck, and the like. It is preferable to use an injection needle having almost no variation. Incidentally, when an injection needle or the like is used, the needle tip side, which is obliquely cut beforehand, can be used as the air circulation port 11. Also in terms of the size of the tube, an outer diameter of 0.31 mm, an inner diameter of 0.13 mm, and an outer diameter of 0.2 mm may be appropriately adopted depending on the width of the tip to be adsorbed. It is possible.

The vacuum chuck 1 of this embodiment is constructed by combining the above-mentioned box 2 and thin tube 3 in the following procedure. That is, first, a large number of thin tubes 3 are inserted into the opening 10 of the box 2 in parallel. At that time, the air flow port 11 of the thin tube 3 is arranged in the empty chamber 8 of the box body 2, and the suction port 12 on the opposite side is arranged so as to project outward from the box body 2,
Unify the tube insertion direction. Secondly, the one end side of each thin tube 3 is pressed against the upper lid 4 of the box body 2, and the thin tube 3 is laterally pressed by the pressing screw 13 screwed to the lower frame 6,
Put the tubes together. Thirdly, the gap formed around each thin tube 3 is filled with an adhesive or the like, and the thin tube 3 is fixed to the opening 10 of the box 2. Fourthly, the suction port 12 of each thin tube 3 is uniformly ground or ground to form a flush suction surface S. The vacuum chuck 1 is configured by the above procedure.

Next, the suction function of the vacuum chuck 1 of the present embodiment having the above structure will be described. First, when a hose connected to a vacuum pump (not shown) is connected to the air suction port 9 of the box 2 and the vacuum pump is operated, the air around the chuck flows from the suction port 12 of each thin tube 3 to the same air flow. Retracted through mouth 11. Here, in this embodiment, since the length of the thin tube 3 is extremely longer than the inner diameter, the air resistance in each thin tube 3 becomes very large. Moreover, since the suction surface S of the chuck is formed flush with the suction port 12 of the thin tube 3 having a very small diameter and almost no variation in size, when sucking air from the air suction port 9, Air is evenly sucked from the suction port 12, and as a result, a uniform suction force is generated on the entire suction surface S of the vacuum chuck 1. Moreover, since the thin tubes 3 are fixed in parallel, the direction of the suction force is also unified. Therefore, when the chips are actually sucked by the vacuum chuck 1, a uniform suction force acts on all the chips, and as a result, the plurality of chips arranged on the wafer are surely sucked by the suction surface S. It becomes possible to do.

Further, in the vacuum chuck 1 of the present embodiment, a portion corresponding to the peripheral edge portion 57 (FIGS. 4 and 5) of the conventional vacuum chuck has a very thin wall thickness of the thin tube 3 (in the present embodiment, 0. Since it is composed of only about 1 mm), the air wrapping around the chuck is improved, and the air pressure of the air on the wafer in the lateral direction is significantly reduced. As a result, it is possible to reliably prevent the chip arrangement from being disturbed at the time of adsorption.

In this embodiment, the chucking surface S of the chuck is
Is formed by polishing (or grinding) so that
There is no risk of damaging the chip during adsorption.

In the structure of the above embodiment, the air flow port 11 is formed by cutting one end side of the thin tube 3 obliquely, but the present invention is not limited to this and, for example, although not shown, Both ends of the thin tube are cut substantially at right angles to the axial direction, and one end side arranged in the vacant chamber 8 when being fixed to the opening 10 of the box 2 is slightly separated from the upper lid 4, and one end thereof is It is also possible to use the side as the air circulation port. However,
The former is more advantageous in view of the assemblability of the chuck. This is because, when fixing the thin tubes to the opening of the box, in the former case, the fixed position of a large number of thin tubes 3 can be held simply and reliably by merely abutting one end of the tube against the lower surface of the upper lid 4. In the latter case, one end of the tube must be held slightly away from the upper lid 4, which complicates the assembly work, and even if each thin tube is cut to the same length, the suction port height is high. Is likely to be uneven.

[0020]

As described above, according to the vacuum chuck of the present invention, when air is sucked from the air suction port, air is sucked uniformly from each suction port due to the air resistance generated in each thin tube. A uniform suction force is generated over the entire suction surface of the chuck formed flush with the suction port. At the same time, the direction of the suction force is unified by fixing the thin tubes in parallel. Therefore, when the chips are actually sucked, a uniform suction force acts on all the chips, and as a result, it is possible to surely suck the plurality of chips arranged on the wafer by the suction surface. Become. Furthermore, since the chucking surface of the chuck is formed flush, scratches on the chip during chucking are prevented. In addition, since the part corresponding to the peripheral edge of the conventional vacuum chuck is composed only of the wall thickness of the thin tube, the air wrapping around the chuck is improved and the wind pressure of the air from the lateral direction on the wafer is greatly increased. And the disorder of the chip arrangement at the time of adsorption is prevented.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a vacuum chuck of the present invention.

FIG. 2 is a view on arrow A in FIG.

FIG. 3 is a perspective view of a main part of the vacuum chuck shown in FIG.

FIG. 4 is an explanatory diagram of a conventional vacuum chuck.

FIG. 5 is an explanatory view of another conventional vacuum chuck.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vacuum chuck 2 Box body 3 Capillary tube 8 Vacancy 9 Air suction port 10 Opening 11 Air circulation port 12 Suction port S Suction surface

Claims (1)

[Claims] 1. A box having an empty chamber formed therein and having an air suction port and an opening communicating with the empty chamber, and fixed in parallel and in close contact with the opening of the box. Comprising a plurality of thin tubes, each thin tube, while one end side is arranged in the chamber of the box as an air flow port, the other end side as an adsorption port outward from the box A vacuum chuck characterized in that it is arranged so as to project and a suction surface flush with the suction ports is formed.