JPS61214937A - Attractive holder - Google Patents

Abstract

PURPOSE:To enable a holder to hold a thin plate in every size, by closing a valve, which controls air from a suction part to an exhaust port, communicating with an attracting groove, not brought into contact with a material to be attracted, of the plural attracting grooves, having a predetermined distance from the center of an attracting surface, and preventing a decrease of negative pressure. CONSTITUTION:If a wafer 2 is placed on a wafer chuck 1 by an automatic hand, a holder, bringing no wafer onto a pin 4a in the outermost attracting groove 5a, leaves the pin 4a as lifted by a spring 7 and cuts off communication with an exhaust hole 3. While the holder, depressing pins 4b, 4c due to downward pressing of the automatic hand and connecting attracting grooves 5b, 5c with the exhaust hole 3, holds the wafer to an attracting surface by applying a negative pressure to the wafer. While a protrusive distance of the pin from the attracting surface is decreased to a fine value, and if setting tension of the spring 7 is increased larger than weight of the pin by several grams, the holder, depressing the pin by dead weight of the wafer 2 and attracting force of an attracting groove 6, also enables the exhaust hole to communicate with the attracting groove.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a suction and holding device for suctioning and holding a thin plate-shaped article such as a semiconductor wafer by applying negative pressure thereto.

[Prior art 1] In a conventional suction holding device, a plurality of suction grooves are provided within a predetermined distance corresponding to the radius of the object to be suctioned from the center of the suction surface,
Negative pressure was applied to the object on the suction surface through suction ports on the suction surface that communicated with the suction grooves, thereby suctioning and holding the object on the suction surface.

For this reason, if the size of the object to be attracted differs, there is an inconvenience that a suction and holding device having suction grooves suitable for suctioning and holding the object must be selectively used.

[Problems to be Solved by the Invention] An object of the present invention is to provide a suction and holding device that can suction and hold an object to be suctioned even if the size of the object differs by a single suction and holding device.

[Means and effects for solving the problem] This object is, according to the present invention, to provide a plurality of suction grooves spaced a predetermined distance from the center of the suction surface, a suction port on the suction surface communicating with each suction groove, It includes an exhaust hole that communicates with the suction port, a valve that controls the inflow of air from the suction port to the exhaust hole, and a valve selection control means that operates only the valve selected according to the size of the object to be attracted. This is achieved by an adsorption holding device.

When the valve is in the closed position, it prevents air from flowing into the exhaust port from the suction port and does not apply negative pressure to the object to be sucked through the suction groove communicating with the suction port, but when the valve is in the open position, it prevents air from flowing into the exhaust hole. When the air is in the suction port, air is allowed to flow from the suction port into the exhaust hole, and negative pressure is applied to the suction object through the suction groove communicating with the suction port, thereby suctioning and holding the object on the suction surface. The valve selection control means automatically maintains the valve selected according to the size of the adsorbed object in the same state, holds the other valves in the closed state, and applies negative pressure to the adsorbed object to apply negative pressure to the adsorbed surface. Holds by adsorption. Alternatively, the valve control means manually adjusts the valves selected according to the dimensions of the object to be attracted and holds them in a closed state, and holds the other valves in an open state to attract and hold the object to be attracted.

In the structure of this first embodiment, the valve is composed of:
The pin has a handle that is slidably inserted into the suction port and a flange larger than the suction port, and the valve selection control means is in contact with the flange of the pin and constantly presses it against the suction port. A spring that holds the valve closed.

During operation, when the wafer 2 is transferred from the pre-alignment station 11 to the wafer chuck 1 by the automatic hand 9, the pin 4a is pushed up by the spring 7 because the wafer 2 does not come on top of the pin 4a in the outermost wafer suction groove 5a. In this state, communication with the exhaust hole 3 is cut off. On the other hand, the inner suction @@Sb, 5c is pressed by the auto hand 9 to become the pin 4b.

4C is pushed down and communicates with the exhaust hole 3 through the suction port, and as a result, negative pressure acts on the wafer 2, and the wafer 2 is held by suction on the suction surface.

[Embodiment] FIG. 1 is a longitudinal sectional view of a first embodiment of the suction holding device of the present invention, and FIG. 2 is a plan view thereof.

FIG. 3 is a diagram illustrating the suction and transfer operation of the suction target object by the suction holding device of the present invention.

In Figure 1.2, 1 is a wafer chuck, 2 is a wafer, 3 is an exhaust hole, 4a, 4b, 4c are pins for opening and closing the suction port communicating with the suction groove on the suction surface of the wafer chuck, 5a, 5b , 5c is a suction groove for suctioning the wafer 2, 6 is a central suction groove where negative pressure is always applied, and 7 is a pin that is pushed up when the wafer 2 is not placed on the suction surface to remove air from the suction groove. a spring sealing the inflow passage of the
8 is a joint for connecting to a suction pump (not shown).

In FIG. 3, 9 is the pre-alignment station 11.
10 is a cylinder for raising and lowering this automatic hand 9; 11 is a pre-alignment station for positioning the wafer 2 before supplying it to the wafer chuck 1; 12 indicates positioning pins, respectively.

The automatic hand 9 does not have to be used to push down the pins 4b and 4c. For example, the amount of protrusion of the pins 4a, 4b, and 4c from the suction surface of the wafer chuck is set to a very small amount (0, 11111
degree), and the setting force of spring 7 is also set by pins 4a, 4.
If the number of holes is the same as that of mold openings b and 4c, the pins 4 will be held together by the weight of the wafer 2 and the suction force of the center suction groove 6.
Push down a, 4b, and 4c, and connect exhaust hole 3 and suction groove 5a.
, 5b.

5C can also be communicated.

FIG. 4 is a longitudinal sectional view of a second embodiment of the suction holding device of the present invention. In this embodiment, the valve is slidably inserted into the suction port, and includes an upper handle portion having a screwdriver receiving groove formed at the top, a collar portion that is integral with the upper handle portion and larger than the intake port, and a collar portion that is larger than the intake port. The valve selection control means consists of a pin that is integral with the upper handle and has a lower handle that extends to the opposite side, and the valve selection control means includes a screw formed in the lower handle and a screw that is screwed into this and holds the pin fixedly. Consists of a perforated hole.

FIG. 4 shows a second embodiment of the suction holding device of the present invention.

The difference from the first embodiment is that the upper handle part 14 is slidably inserted into the suction port and has a driver receiving groove 18 at the top.
A valve is formed from a pin having a collar portion 15 that is integral with the upper handle portion and is larger than the inlet, and an F-square handle portion 16 that is integral with the collar portion and extends to the opposite side of the upper handle portion. A valve selection control means is constituted by a screw formed in the lower handle part 16 of the pin and a blind screw hole 17 of the wafer chuck which is screwed into the screw and holds the pin in the closed position. It is that you are.

In this embodiment, the suction port located outside the outer circumference of the wafer 2 to be sucked is closed in advance by a valve, and the suction port located inside the outer circumference of the wafer 2 is opened in advance.

In that case, insert the tip of the screwdriver into the groove 1 of the upper handle part 14 of the pin.
8, and rotate the pin in the direction in which the lower handle 16 of the pin is pulled out from the blind screw hole 17 until the collar 15 closes the suction port. The pin of the suction port located inside the outer circumference of the wafer 2 is rotated in the direction in which the lower handle 16 of the pin enters the fully threaded hole 17 until the collar 15 separates from the suction port and opens it.

The suction operation is the same as that in the first embodiment, so a description thereof will be omitted.

Although the embodiment of the present invention has been described as a device for suctioning a semiconductor wafer, it can of course be used for suctioning and holding other thin plate-like objects. Further, although the suction grooves have been described as being formed in concentric circles, they may be rectangular or other loop-shaped grooves.

Note that the loop may be partially cut, that is, the loop may not be completely connected.

[Effects of the Invention] The present invention makes it possible to suction and hold thin plates of various sizes using a single suction and holding device with a simple configuration, and eliminates the conventional inconvenience of selectively using different suction and holding devices for each size. be.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a first embodiment of the present invention. FIG. 2 is a plan view of the first embodiment. FIG. 3 is a perspective view illustrating how the suction holding device is used. FIG. 4 is a longitudinal sectional view of a second embodiment of the invention. In the figure: 1: Wafer chuck, 2: Wafer, 3: Exhaust hole, 4a;
4b; 4c: Pin, 5a: 5b: 5c: Suction groove, 6: Center suction groove, 9: Auto hand, 10 Niji cylinder, 11 Niburi alignment station, 12: Positioning pin, 14: Upper handle, 15: collar, 16: lower handle, 17: N screw hole, 18 groove on upper handle. Figure 1 Figure 2

Claims (1)

[Claims] 1. A plurality of suction grooves spaced a predetermined distance from the center of the suction surface, an inlet on the suction surface that communicates with each suction groove, an exhaust hole that communicates with the inlet, and an inlet. What is claimed is: 1. An adsorption/holding device comprising: a valve for controlling the inflow of air from the air into an exhaust hole; and a valve selection control means for operating only the valve selected according to the size of an object to be adsorbed. 2. The suction grooves are formed into a plurality of loops separated by a predetermined distance from the center of the suction surface, and the valve has a handle portion that is slidably inserted into the suction port, and a handle portion that is larger than the suction port. and the valve selection control means is a spring that abuts the collar of the pin and constantly presses it against the suction port to hold the valve in a closed state. The suction holding device described in Section. 3. The suction grooves are formed into a plurality of loops separated by a predetermined distance from the center of the suction surface, and the valve is slidably inserted into the suction port, and the upper part has a screwdriver receiving groove formed at the top. From a pin having a handle, a collar that is integral with the upper handle and is larger than the suction port, and a lower handle that is integral with the collar and extends to the opposite side of the upper handle. The suction holding device according to claim 1, wherein the valve selection control means comprises a screw formed in the lower handle and a threaded hole that is screwed into the screw and holds the pin fixedly. .