JPH0417311Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a suction table that suctions and fixes objects placed on the table by suction action.

As an example of a conventional suction table, as shown in FIG. 3, a porous object 2 such as a porous metal having a smaller diameter than the object 1 is placed in the center of the suction table 3, and the lower surface of the porous object 2 is suctioned. By reducing the pressure, the object 1 on the suction table was fixed by suction. However, this conventional device had the following drawbacks. For example, the process of manufacturing semiconductor devices includes a process of grooving the wafer (mounted object 1) to separate it into chips while applying coolant, or a process of cleaning the wafer. In such a process, in the above-mentioned conventional apparatus, the dirty water W accumulated on the outer circumference of the wafer 1 is passed through a small gap on the lower surface of the outer circumference of the wafer 1 by a suction action, and is absorbed into the porous structure as shown by the arrow in the figure. Sucked into object 2. As a result, a layer of water is formed between the suction surface of the porous object 2 and the wafer 1, which causes them to stick together, making it difficult to separate the wafer 1 when trying to remove it, and damaging the wafer if you try to separate it forcibly. There were accidents such as Further, since dirty water is sucked in, the back side of the wafer becomes dirty, and furthermore, the suction holes of the porous body 2 gradually become clogged, resulting in a decrease in suction force.

This invention provides a suction table that solves the drawbacks of the conventional devices described above. An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a plan view of the present invention, and FIG. 2 is a sectional view taken along the line -- in FIG. In the figure, reference numeral 3 denotes a suction table, and a suction plate 2 made of, for example, a porous material such as porous metal is provided in the center of the suction table.

An appropriate number of conductive holes 4 are provided on the upper surface of the suction table 3, close to the outside of the outer periphery of the suction part of the suction table, and inside the outer periphery of the wafer, and having openings on the upper and lower surfaces of the table. Perforated through. In order to make the present invention more effective, 5 is formed on the top surface of the suction table 3 so that the plurality of conduction holes 4 communicate with each other, and the top surface of the suction table is close to the outside of the outer periphery of the suction part. This is a conduction groove 5 having an opening inside the outer periphery of the object. In this way, the suction table 3 is provided with a conductive path through the conductive holes 4 or the conductive grooves 5 for sucking outside air from the lower surface of the table when the wafer 1 is placed on the table.

In such a configuration, when the object 1 is placed on the suction plate 2 so as to cover the conduction hole 4 and the lower surface of the suction plate 2 is depressurized by suction, the suction action is caused by the large number of small parts of the suction plate 2. It extends from the hole to the conduction hole 4 via the back surface of the mounting object 1. However, its suction action does not reach the dirty water W accumulated around the outer periphery of the placed object 1.
In other words, when the conduction holes 4 or the conduction grooves 5 are arranged as shown by the arrows in Fig. 2 due to the suction action,
Atmospheric air is sucked from the groove toward the bottom surface of the suction plate 2, but since there is no difference in air pressure between the dirty water W and the conduction hole 4 or the conduction groove 5, the air is sucked into the conduction hole 4 or the conduction groove 5. Do not suck up water W. Therefore, unlike conventional devices, a layer of water does not form between the top surface of the suction plate 2 and the placed object 1, and the placed object 1 can be easily removed, and the back surface of the placed object 1 is not soiled. Alternatively, a practically effective suction table could be provided without clogging the large number of small holes in the suction plate 2.

In addition, in the above embodiment, a porous material was used as the adsorption plate 2.
The present invention can also be applied to a suction plate 2 made of a porous material with a large number of small holes formed therein. It can also be applied to a suction table configured to form concentric grooves or spiral grooves on the suction table, and to suck in from one end of the groove to apply suction to the entire circumference of the groove, thereby attracting the object placed on the suction table. Of course it is possible.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the present invention, FIG. 2 is a sectional view taken along the line -- in FIG. 1, and FIG. 3 is a sectional view of a conventional device. 1... Placement object, 2... Suction plate, 3... Suction table, 4... Conductive hole, 5... Conductive groove.

Claims (1)

[Claims for Utility Model Registration] (1) In a suction table that suctions and fixes a placed object by suction, a portion of the suction table that is close to the outside of the outer periphery of the suction part and inside of the outer periphery of the placed object is exposed to outside air. A suction table characterized by having an opening for a conductive path. (2) The suction table as set forth in claim 1 of the utility model registration, characterized in that the conduction path communicating with the outside air is a plurality of conduction holes drilled through the top and bottom of the table. (3) In the description of claim 1 of the utility model registration claim, the conduction path communicating with the outside air is formed so as to communicate with a plurality of conduction holes drilled through the top and bottom of the table and each opening of the conduction holes. . A suction table, characterized in that the upper surface of the suction table is formed of a conductive groove that is close to the outside of the outer periphery of the suction part and has an opening inside the outer periphery of the placed object.