KR20040075563A - Wafer stage unit for exposure equipment - Google Patents

Abstract

PURPOSE: A wafer stage unit of exposure equipment is provided to maintain constantly temperature of a wafer by performing rapidly a heat exchange process between a wafer and a table. CONSTITUTION: A table(140) is used for absorbing a wafer. A table cooling unit is used for cooling the table. The table cooling unit includes a heat exchange part and a cooler(164). The heat exchange part is formed in the inside of the table in order to cool the table by using the cooling water. The cooler is installed at an outside of a wafer stage unit in order to cool the cooling water and supply the cooling water to the heat exchange part. The table cooling unit further includes a temperature sensor(168) for detecting the temperature of the table and a temperature controller(170) for controlling the cooler.

Description

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

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manufacturing apparatus for a semiconductor device, and more particularly, to a wafer stage unit of an exposure system capable of controlling the temperature of a table on which a wafer is placed.

The life of semiconductor exposure equipment is the realization of accurate alignment and finer circuit line width. As a result, continuous improvements have been made in the way optical components and light are used and aligned. However, the wafer stage, in which the fixing wafer is in direct contact and stays for a long time during exposure, has only been improved in flatness without any temperature control device. For example, the degree of alignment at the wafer stage is closely influenced by the temperature of the wafer and the surrounding environment of the wafer. In order to minimize this problem, improvements such as developing and installing an air shower device or changing an internal air conditioning system of a facility have been made, but the effect is insignificant.

For example, the wafer enters the exposure apparatus while already being damaged by the temperature change and the expansion rate according to the baking in the coating process. In the exposure apparatus, the wafer may be expanded or contracted by several nm or less while being affected by the ambient temperature while moving through direct contact with heating elements such as various lamps and solids made of metal and ceramic materials.

In addition, when the wafer is exposed to ultraviolet light, thermal energy containing ultraviolet light, which directly affects the wafer, and expansion and contraction of the wafer may occur due to the release of energy generated during reaction with the photoresist. These problems are a major factor in reducing the exposure quality of the wafer.

The present invention has been made to solve such a conventional problem, and an object thereof is to provide a wafer stage unit of a novel type of exposure system that can improve the exposure quality of a wafer.

1 is a perspective view of a wafer stage unit of an exposure apparatus according to a preferred embodiment of the present invention;

2 is a view showing the configuration of a table cooling apparatus.

* Explanation of symbols for the main parts of the drawings

140: table

160: table cooling unit

162: cooling water line

164: cooler

166a: supply pipe

166b: recovery pipe

168 temperature sensor

170: temperature control unit

According to a feature of the present invention for achieving the above object, the wafer stage unit of the exposure system has a table cooling means capable of cooling the table. The table cooling means is formed inside the table, the heat exchanger for cooling the table with the supplied cooling water; A cooler installed outside the wafer stage unit and cooling the cooling water recovered from the heat exchanger to resupply to the heat exchanger, a temperature sensor installed on the table to detect a temperature of the table; And a temperature control unit controlling the cooler to cool the recovered cooling water to a low temperature in response to the detection signal of the temperature sensor.

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. 1 and 2. In addition, in the drawings, the same reference numerals are denoted together for components that perform the same function.

1 is a perspective view of a wafer stage unit of an exposure apparatus according to a preferred embodiment of the present invention. 2 is a view showing the configuration of a table cooling apparatus.

Generally, the stage unit used for the stepper installation of a semiconductor exposure process is equipped with the XY-stage which can move to an X-axis direction and a Y-axis direction, and each stage is linear reciprocating movement by each drive motor, have.

1 shows a schematic arrangement of a wafer stage unit according to a preferred embodiment of the present invention.

As shown, the wafer stage unit 100 is provided with a stage base 110 that supports the apparatus, the Y stage 120 is seated on the stage base 110, and the X stage 120 is positioned on the Y stage 120. The stage 130 is seated.

Although not shown, an X stage driving motor and a Y stage driving motor for generating a driving force for reciprocating linear movement of the stages 120 and 130 are provided at one side of each stage 120 and 130, respectively.

The X stage 130 is provided with a table 140 that takes over a wafer from a transfer robot (not shown) and vacuum-adsorbs it. The table 140 is provided with a lift means 150 that supports the bottom surface of the wafer w when loading or unloading the wafer w and which lifts the wafer up and down from the turntable.

2, the wafer stage unit 100 according to the present invention has a table cooling device 160 for cooling the table 140 to a constant temperature. The table cooling device 160 is formed inside the table, and is provided with a cooling water line 162 which is a heat exchanger for cooling the table with the supplied cooling water, and is provided outside the wafer stage unit and from the cooling water line 162. A cooler 164 for cooling the recovered coolant and supplying it back to the coolant line, a supply pipe 166a connecting the inlet 162a of the coolant line and the outlet 164a of the cooler, and an outlet 162b of the coolant line And a recovery pipe 166b connecting the inlet 164b of the cooler, a temperature sensor 168 for detecting a temperature of the table, and a temperature controller for controlling the cooler 164 in response to a detection signal of the temperature sensor ( 170).

As described above, the wafer stage unit of the present invention can maintain the temperature of the wafer placed on the table by the table cooling apparatus.

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 may be implemented by modifying the stage unit. 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 wafer stage unit in the exposure equipment according to the present invention has been shown according to the above description and drawings, which are merely described for example and various changes and within the scope without departing from the technical spirit of the present invention. Of course, change is possible.

According to the present invention, when the wafer is placed on the table, heat exchange between the wafer and the table is performed quickly. Therefore, the wafer can be kept constant at a desired temperature, and as a result, dLT, which can be generated from the influence of ultraviolet rays during exposure, has the advantage of minimizing thermal strain, improving alignment and reducing the change in line width across the wafer surface. .

Claims (4)

In the wafer stage unit of the exposure system: A table which takes over a wafer and vacuum-adsorbs it; And a table cooling means capable of cooling the table. The method of claim 1, The table cooling means A heat exchanger formed inside the table and cooling the table with the supplied cooling water; And a cooler installed outside the wafer stage unit to cool the cooling water recovered from the heat exchange unit and to resupply the coolant to the heat exchange unit. The method of claim 2, The table cooling means A temperature sensor installed at the table for detecting a temperature of the table; And a temperature control unit for controlling the cooler to cool the recovered cooling water to a low temperature in response to the detection signal of the temperature sensor. The method of claim 1, The unit is An X-axis moving plate installed at an upper portion of the table and movable in the X-axis; An exposure system further installed on the left and right sides of the X-axis moving plate, guiding the X-axis moving plate to move in the X-axis direction, and moving along the X-axis moving plate to the Y-axis moving plate; Wafer stage unit.