KR20030012643A - Wafer stage for exposure equipment - Google Patents

Abstract

PURPOSE: A wafer stage of exposure equipment is provided to improve productivity by removing generation of a local focus due to contamination of a wafer. CONSTITUTION: A wafer clamping apparatus(100) is formed with an up/down robot(110) and a couple of clamping robots(120). The up/down robot(110) is used for lifting a wafer(W) from a transferring arm to a clamping position. The clamping robots(120) are used for grasping an edge of the wafer(W) of the clamping position. The clamping robot(120) is formed with a driving portion(122), a shaft(124), and a clamp ring(126). The shaft(124) is moved to a front or a rear direction by the driving portion(122). The clamp ring(126) is installed at one end of the shaft(124) in order to grasp the edge of the wafer(W). The driving portion(122) can be formed with a cylinder.

Description

Wafer stage of exposure equipment {WAFER STAGE FOR EXPOSURE EQUIPMENT}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing facility of a semiconductor device, and more particularly, to a wafer clamping chuck of a semiconductor manufacturing facility capable of preventing local focus failure.

In the semiconductor process, a single product is produced through the manufacturing process of diffusing / photo / etch / cvd / implantor / metal.

During this cycle, the photo process is affected by contamination of the entire process. In particular, when the wafer backside is contaminated, a local focus failure of the contaminated portion occurs, causing a patterning failure. This contamination also contaminates the wafer chucks that chuck the wafers of the exposure equipment, causing patterning failures in subsequent lots of wafers as well, resulting in a large amount of failures. Cost loss)

Local defocus is generally referred to as local defocus, which occurs less frequently in a layer having a cleaning process in the entire process, but is often generated in a later layer such as a metal process without a cleaning process.

This local defocus can be done by visual inspection of the wafer, but it takes a lot of time to find the defect and once it occurs, the lot is usually about 6-10lots until it is discovered because of contamination. Fortunately, when found in the photo process, rework is possible, but it causes significant losses. If it is not found in the photo process, the yield may be reduced by local defocus.

As such, it is very important to avoid the contamination of the wafer backside, which causes a lot of defects, but it is quite difficult to completely eliminate it, because the whole process must be managed.

1 shows a wafer chuck used in a general exposure apparatus. Referring to FIG. 1, the wafer w is sucked and fixed on the chuck 10 by a vacuum suction force pumped through a vacuum suction hole from a vacuum generator, not shown.

However, since the chuck 10 of this type has a considerably wider contact area directly contacting the wafer w, a partial region of the wafer may be bent due to foreign matter such as particles.

Of course, the warping of the wafer as a whole can be corrected to some extent. However, if a step is partially formed on the wafer surface, it is a poor focusing phenomenon in which a bridge is formed or the pattern is not formed well during exposure. This will greatly affect the occurrence of local focus.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and an object thereof is to provide a wafer clamping chuck of a semiconductor manufacturing facility in which local local focus due to wafer back surface contamination does not occur.

1 is a wafer chuck used in a typical exposure facility;

2 is a perspective view of a wafer clamping device of a stepper installation according to a preferred embodiment of the present invention;

3 is a side view of the wafer clamping device of the stepper facility shown in FIG. 2;

4 illustrates a wafer loading process.

* Explanation of symbols for the main parts of the drawings

100: wafer clamping device

110: up / down robot

120: clamping robot

122: drive unit

124: shaft

126: Clamp Ring

According to a feature of the present invention for achieving the above object, there is provided a wafer clamping apparatus, comprising: an up / down robot for lifting a wafer taken over from a transfer arm to a clamping position; And a pair of clamping robots for holding only the edge of the wafer from the left and right sides of the wafer lifted to the clamping position.

The clamping robot in the present invention as described above is a drive unit; A shaft which is moved back and forth by the driving unit; And a clamp ring mounted at one end of the shaft to grip an edge of the wafer.

In the present invention as described above, the driving unit may be a cylinder.

In the present invention as described above, the clamp ring may have the same curved surface as the circumference of the wafer.

In the present invention as described above, the clamp ring may be detachably installed from the shaft.

For example, embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited by the embodiments described below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Accordingly, the shape of the elements in the drawings and the like are exaggerated to emphasize a clearer description.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 2 to 4. In addition, in the drawings, the same reference numerals are denoted together for components that perform the same function.

Of the accompanying drawings, Figure 2 is a perspective view of the wafer clamping device of the stepper installation according to a preferred embodiment of the present invention. 3 is a side view of the wafer clamping device of the stepper facility shown in FIG. 2. 4 illustrates a wafer loading process.

The stepper used in the semiconductor photo process is arranged by aligning the mask pattern of the reticle on the wafer to be transported and irradiating it using illumination light and a focus lens. An exposure apparatus for forming a circuit pattern on a wafer. The wafer to be conveyed for this photo process is fixed and aligned in the wafer clamping device.

The wafer clamping apparatus 100 used in the semiconductor photo process of the present invention illustrated in FIGS. 2 and 3 includes an up / down robot 110 and a pair of clamping robots 120.

The up / down robot 110 lifts the wafer W taken over from a transfer arm (not shown) to a clamping position.

The pair of clamping robots 120 grips the edges of the wafer from the left and right sides of the wafer W lifted to the clamping position. Looking at the clamping robot 120 in more detail, the clamping robot 120 is a drive unit 122, the shaft 124 is moved back and forth by the drive unit 122, one end of the shaft 124 It is mounted to the clamp ring 126 to hold the edge of the wafer.

The driving unit 122 may be formed of a cylinder for moving the shaft 124 back and forth. The clamp ring 126 has the same curved surface as the circumference of the wafer W, and the clamp ring 126 is detachably installed from the shaft 124 to be changeable according to the wafer size.

As described above, the wafer clamping apparatus 100 of the present invention is structurally clamped at the left and right edges of the wafer in order to prevent local local focus caused by wafer bottom contamination caused by the conventional wafer back contacting the chuck. It has the characteristics.

Referring to FIG. 4, the wafer loading process will be described. After the pre-aligned wafer is lifted by the up / down robot 110, the wafer is clamped by the left and right clamping device 120. Thereafter, the exposure process of the wafer is performed while the up / down robot 110 is lowered.

While many details are set forth in the foregoing description, they should be construed as illustrative of preferred embodiments, rather than to limit the scope of the invention. For example, it will be apparent to those skilled in the art that the present invention can be implemented by modifying the clamping device. Therefore, the scope of the present invention should not be defined by the described embodiments, but should be determined by the technical spirit described in the claims.

In the above, the configuration and operation of the weeping clamping device in the exposure equipment according to the present invention is shown in accordance with the above description and drawings, but this is merely described for example and various changes and within the scope not departing from the technical spirit of the present invention. Of course, change is possible.

By applying the present invention as described above, no local focus can be generated, thereby improving productivity. Flexible clamping is also possible for wafers of various sizes.

Claims (5)

In wafer clamping devices used in exposure equipment: An up / down robot that lifts the wafer taken over from the transfer arm to a clamping position; And a pair of clamping robots for holding only the edges of the wafer from the left and right sides of the wafer lifted to the clamping position. The method of claim 1, The clamping robot A drive unit; A shaft which is moved back and forth by the driving unit; And a clamp ring mounted to one end of the shaft to grip an edge of the wafer. The method of claim 2, Wafer clamping apparatus of the exposure facility, characterized in that the drive unit is a cylinder. The method of claim 2, And said clamp ring has the same curved surface as the circumference of the wafer. The method of claim 2, And the clamp ring is detachable from the shaft.