KR200234113Y1 - Cooling-unit for semiconductive wafer - Google Patents

Abstract

The present invention relates to a cooling unit of a semiconductor wafer, which is provided in the chamber 10 and constitutes a cooling unit of the semiconductor wafer for uniformly cooling the semiconductor wafer W heated at a high temperature. And a plurality of thermal modules 24 having cold junctions 26 for absorbing heat and hot junctions 27 for dissipating heat on both sides of the thermoelectric element 25, and the cold junctions 26 The upper panel 22 is attached to the bottom surface and the wafer W is placed on the upper surface, and the lower plate 23, 43, 63, 83 to which the on-contact portion 27 is attached to the upper surface and the thermo module 24 Cool plate 20 is attached to the edge and the center of the upper and lower plates; And flow paths 23a, 43a, 63a, and 83a, which are internally installed in the lower plate 23, 43, 63, and 83 in a pipeline to pass cooling water or cooling gas and pass through the centers of the hot-contact points 27. It provides; provides a cooling unit of the semiconductor wafer to control the cooling conditions more accurately and simply, and to maintain a uniform cooling temperature of the entire wafer.

Description

Cooling unit for semiconductor wafers {Cooling-unit for semiconductive wafer}

The present invention relates to a cooling unit of a semiconductor wafer using a thermal module so that the cooling conditions of a semiconductor wafer desired by a user can be more accurately and simply controlled, and the cooling temperature of the entire wafer is maintained uniformly.

Modern semiconductor processing systems go through a series of steps to process provided semiconductor wafers. Typically, each processing step is accomplished in a respective processing chamber and a robot delivery mechanism delivers the wafer from each step to the step in the system. Each processing step requires a specific environment that is different from other steps in the system. As above, after the processing in one step is completed, for example operating at very high temperatures in excess of 400 ° C., the wafer must be cooled before being transferred to the next step. In some instances, placing a hot wafer in some form of the surrounding environment causes an undesired reaction that renders the wafer useless. In addition, after processing in the final stage of the semiconductor processing system, the wafer must be cooled before being placed in a plastic delivery cassette.

As such, when the wafer is cooled, how quickly the wafer is cooled to a certain temperature and evenly cooled by the microscopic error directly affects the yield of the semiconductor device, so that temperature control is precise and temperature compensation time. There is a need for a cooling means for this fast wafer.

An object of the present invention is to provide a cooling unit for a semiconductor wafer using a thermal module so that the temperature of the entire semiconductor wafer is evenly cooled.

1 is a schematic cross-sectional view showing a cooling unit of a semiconductor wafer according to the present invention,

FIG. 2 is a view showing a part of the cool plate of FIG. 1 applied to an 8-inch wafer, and showing a flow path built into a lower plate.

3 is a view showing another embodiment of FIG.

FIG. 4 is a view showing a part of the cool plate of FIG. 1 applied to a 12-inch wafer, and showing a flow path built into a lower plate.

5 is a view showing another embodiment of FIG.

6 is a schematic diagram illustrating performing temperature control of the thermal module of FIG. 1.

<Explanation of symbols for the main parts of the drawings>

10 ... chamber 11 ... base

20 ... Cool Plate 21 ... Push Pin

22 ... Top 23,43,63,83 ... Bottom

23a, 43a, 63a, 83a ... Flow Furnace 23b, 43b, 63b, 83b ... Supply Port

23c, 43c, 63c, 83c ... outlet 24 ... thermo-module

25 ... thermoelectric element 26 ... cold spot

27 ... hot spot 28 ... thermo-stat

31 ... connection line 32 ... amplifier

33.Control

In order to achieve the above object, the cooling unit of the semiconductor wafer according to the present invention is installed in the chamber, and constitutes the cooling unit of the semiconductor wafer for uniformly cooling the semiconductor wafer heated to a high temperature. A plurality of thermal modules having a cold junction portion for absorbing heat and a hot junction portion for dissipating heat on both sides of the thermoelectric element, an upper plate on which the cold junction portion is attached to a bottom surface, and the wafer is placed on an upper surface, and the on contact portion is an upper surface A cool plate configured to be attached to the lower plate and to which the summer module is attached to an edge and a center of the upper and lower plates; And a flow path internally installed in the lower plate in a pipeline to flow the cooling water or the cooling gas and passing through the center of the hot-contact points.

According to the present invention, the flow passage has a 'S' shape so that the supply port and the discharge port is provided opposite to the periphery of the lower plate, respectively, the flow path is provided so that the supply port and the discharge port is adjacent to each other on the peripheral side of the lower plate It is desirable to have a 'Y' shape as much as possible.

According to the present invention, the flow path is formed so as to form an 'S' shape inside the edge portion past the edge portion so that the supply port and the discharge port is opposed to the periphery of the lower plate, respectively, and the flow passage and the discharge port of the lower plate It is preferable to form a 'U' shape inside the edge portion past the edge portion so as to be adjacent to each other on one side of the circumference.

Therefore, the cooling unit of the semiconductor wafer according to the present invention uniformly arranges the electronic cooling thermo module having the cold junction portion and the hot contact portion on the wafer, and rapidly cools the hot wafer from the cold junction portion and simultaneously cools the on-contact portion. By heat dissipation with a plate, the temperature compensation time is fast, the cooling temperature of the whole wafer is maintained uniformly, and as a result, the yield of a semiconductor element is improved.

With reference to the accompanying drawings, the cooling unit of the semiconductor wafer having such a feature will be described in detail the configuration and operation.

As shown in FIG. 1, the cooling unit of the semiconductor wafer according to the present invention is installed in the chamber 10 and the chamber 10, and the semiconductor wafer W is seated on the upper surface of the semiconductor wafer. A cool plate 20 for cooling the furnace is provided.

The cool plate 20 is installed on the base 11 in the chamber 10 and is applicable to cooling of the 8-inch or 12-inch wafer W. The semiconductor wafer W may be supported and placed on the upper surface. The upper plate 22 is provided with a fixing pin 21, and the lower plate (23, 43, 63, 83) supported by the base (11). Here, aluminum (Al) is preferable as the material of the upper and lower plates.

A plurality of electronic cooling thermo modules 24 are installed between the upper plate 22 and the lower plates 23, 43, 63, 83, and the thermo module 24 is applied with a current. A semiconductor thermoelectric element 25 absorbs or emits heat, and both sides of the thermoelectric element 25 have a cold contact portion 26 that absorbs heat and an on-contact portion 27 that emits heat. In this case, the material of the cold junction 26 and the hot junction 27 is preferably ceramic.

The cold contact portion 26 is attached to contact the bottom surface of the upper plate 22 on which the wafer W is placed, and the on-contact portion 27 is attached to the upper surface of the lower plates 23, 43, 63, 83. . In addition, the thermo module 24 is disposed such that the cold contact portion 26 and the hot contact portion 27 are distributed to the edge and the upper center of the upper and lower plates.

2 to 5, there are flow paths 23a, 43a, 63a, and 83a made of stainless steel pipes through which cooling water or cooling gas flows, as shown in FIGS. The flow paths 23a, 43a, 63a, and 83a communicate with supply and discharge ports through which cooling water or cooling gas is supplied and discharged, and the body passes through contact center portions of the hot-contact points 27. Here, the lower plate may be manufactured by pouring a cast of aluminum in a stainless pipe.

In more detail, the shape of the flow path 23a applied to the 8-inch wafer W is as shown in FIG. 2, wherein the supply port 23b and the discharge port 23c are formed around the lower plate 23. It has a substantially 'S' shape toward the on-contact portion 27 of the center side via the on-contact portion 27 of the lower plate 23 edge portion so as to face each other, as shown in Figure 3 as another embodiment As described above, the flow path 43a includes the hot-contact points 27 at the edges of the lower plate 43 such that the supply port 43b and the discharge port 43c are adjacent to each other on the circumferential side of the lower plate 43. It has a substantially 'Y' shape directed to the on-contact point portion 27 on the central side via.

On the other hand, the shape of the flow path (63a) applied to the 12-inch wafer is so that the supply port (63b) and the discharge port (63c) is provided to face each of the circumference of the lower plate 63, as shown in FIG. The bottom plate 63 is formed to pass through the on-contact portion 27 of the center portion and the on-contact portion 27 of the inner edge portion and the on-contact portion 27 of the inner edge portion. 'S' shape. As another embodiment, as shown in FIG. 5, the flow path 83a has an edge of the lower plate 83 such that the supply port 83b and the discharge port 83c are provided adjacent to each other on the circumferential side of the lower plate 83. It is provided to form a shape passing through the hot contact portion 27 of the negative portion and the hot contact portion 27 of the inner side of the edge portion, the inner contact portion 27 of the central side, and approximately 'U' shape inside the edge portion To achieve.

In addition, as shown in FIG. 6, the thermal module 24 has a thermo-stat 28 connected to the lower plate to sense the temperature of the lower plates 23, 43, 63, and 83. The thermostat 28 is connected to a control unit 33 for selectively applying power to the thermostat module 24 by a detection signal of the thermostat 28. The control unit 33 is connected to the thermostat 28 by a connection line 31, and the control unit 33 has lower plates 23 and 43 desired by the user so as to control the power of the thermal module 24. (63,83) is set. That is, the temperature of the lower plates 23, 43, 63, and 83 is sensed by the thermostat 28, and the detection signal of the connection line 31 connecting the thermostat 28 and the controller 33 is sensed. Amplified by the intervening amplification unit 32 is transmitted to the control unit 33, the control unit 33 compares the temperature of the detection signal and the temperature of the lower plate (23, 43, 63, 83) preset The thermo module 24 is selectively driven by controlling the power of the thermo module 24 by the signal of the value, and is configured to control the temperature of the wafer W. FIG.

Therefore, the cooling unit of the semiconductor wafer according to the present invention is used to cool the semiconductor wafer to a predetermined temperature after the processing in one step of operating at a high temperature is completed and before being transferred to the next step. For example, in the photolithography process in which a pattern of a mask or a reticle is formed on the wafer to selectively distinguish between a portion to be etched or ion implanted and a portion to be protected, a wafer at which the photoresist is applied is heated to a constant temperature after completion of high temperature treatment. Must be cooled.

To this end, as shown in FIG. 1, a wafer W baked at a high temperature, for example, an 8-inch or 12-inch wafer W is mounted in the chamber 10 of the cooling unit which characterizes the present invention. That is, it is seated so as to be supported by the fixing pin 21 provided on the upper plate 22 of the cool plate 20.

When the 8-inch wafer W is cooled, when a predetermined current is applied to the thermal module 24, the thermoelectric element 25 absorbs high temperature heat of the wafer W through the cold contact portion 26. That is, since a plurality of thermal modules 24 are attached to the edge portion and the center portion of the upper plate 22, the cold junction portion 26 absorbs heat distributed over the entire surface of the wafer W in a short time and evenly. Cooled. Thereafter, the high temperature heat of the wafer W absorbed through the cold contact portion 26 generates heat to the on-contact portion 27 by the thermoelectric element 25.

Heat generated by the on-contact portion 27 is radiated by the lower plate 23 to which the on-contact portion 27 is contacted and attached. As shown in FIG. Since the flow path 23a corresponding to the arrangement of 24 is formed in a substantially 'S' shape so as to pass through the center portion of the on-contact portion 27, when the coolant or the cooling gas flows into the supply port 23b, Cooling water or cooling gas flows through the flow path 23a to cool the hot contact portion 27. Thereafter, the cooling water or the cooling gas that has completed the heat dissipation of the on-contact portion 27 is discharged to the outside through the discharge port 23c. Therefore, the high temperature heat of the wafer W is finally absorbed by cooling water or cooling gas and radiated to the outside.

However, the lower plate 23 as described above has an 'S' shape so that the flow passage 23a therein faces the supply port 23b and the outlet port 23c, respectively, around the lower plate 23. Therefore, when the cool plate 20 is installed in the chamber 10, there is some concern about the inconvenience of installation that requires processing of the supply port 23b and the discharge port 23c that are formed on both sides. In order to compensate for this, as shown in FIG. 3, the supply port 43b and the discharge port 43c flow inside the lower plate 43 to have a 'Y' shape so as to be adjacent to each other on the circumferential side of the lower plate 43. When the furnace 43a is internally installed, since the supply port 43b and the discharge port 43c are positioned adjacent to each other on one side of the lower plate 43, the inconvenience as described above can be eliminated.

On the other hand, in the case of cooling the 12-inch wafer W, the cold contact portion 26 and the hot contact portion of the thermo module 24 are attached to contact the edges of the upper and lower plates, the edges inside the edges, and the center portion. Correspondingly, the flow path 63a inside the lower plate 63 is also edged so that the supply port 63b and the discharge port 63c are provided correspondingly around the lower plate 63, respectively, as shown in FIG. Since it forms a shape passing through the inner edge and the center portion of the edge portion, the cooling water or the cooling gas flows through the flow path 63a, thereby allowing the entire 12-inch wafer W to be uniformly cooled in a short time. .

However, even in such a case, since the flow path 63a has a shape in which the supply port 63b and the discharge port 63c are respectively provided around the lower plate 63, the cool plate 20 is provided in the chamber 10. ), There is some concern about the inconvenience of installation that requires the supply port (63b) and the discharge port (63c) formed on both sides. To compensate for this, as shown in FIG. 5, the supply port 83b and the discharge port 83c are provided in the lower plate 83 so as to be adjacent to each other on the circumferential side of the lower plate 83. When the flow path 83a is formed to have a shape that passes from the edge to the center, the inconvenience as described above is eliminated because the supply port 83b and the discharge port 83c are positioned adjacent to each other on one side of the lower plate 83. It becomes possible.

In addition, as shown in FIG. 6, the cooling unit of the present invention reads the actual temperature of the lower plates 23, 43, 63, and 83 by the thermostat 28, and is recognized by the controller 33. 33) power is supplied from the control unit 33 to the thermo module 24 by a signal as compared with the temperature to be controlled by the user, that is, the preset temperature, so that the thermo module 24 is driven to perform a cooling operation. do. That is, the control unit 33 controls the temperature of the lower plate 23, 43, 63, 83 desired by the user by controlling the power of the summer module 24 in accordance with the current temperature of the lower plate (23, 43, 63, 83). It is. Therefore, temperature control is made easy and temperature control becomes possible more accurately.

As an example, the cooling unit of the semiconductor wafer as described above is applied to the photolithography process by applying a mask or reticle pattern on the wafer to selectively define a portion to be etched or ion implanted and a portion to be protected. After the baking of the wafer is completed, the entire wafer is uniformly cooled in a fast time so as to maintain an error within ± 0.1 ° C within 45 seconds from approximately 220 ° C to 22.5 by the cooling temperature uniformity of the cool plate 20. In this case, the selectivity of the photoresist may be improved, and the uniformity of the amount etched on the wafer may be further improved.

As described above, the cooling unit of the semiconductor wafer according to the present invention uniformly arranges the thermal module having the cold junction portion and the hot junction portion on the wafer, and rapidly cools the high temperature wafer from the cold junction portion. By dissipating the contact portion with a cooling plate, the temperature compensation time is fast, the cooling temperature of the entire wafer is evenly maintained, and as a result, the yield of the semiconductor element is improved.

Claims (5)

In constructing a cooling unit of a semiconductor wafer for uniformly cooling the semiconductor wafer W, which is installed in the chamber 10 and heated to a high temperature, A plurality of thermal modules 24 installed in the chamber 10 and having a cold contact portion 26 absorbing heat on both sides of the thermoelectric element 25 and a hot contact portion 27 dissipating heat; The upper plate 22 having the contact portion 26 attached to the bottom surface and the wafer W is placed on the upper surface, and the lower plate 23, 43, 63, 83 having the on-contact portion 27 attached to the upper surface. A cool plate 20 having the summer module 24 attached to edges and center portions of the upper and lower plates; And Cooling water or cooling gas flows in a pipe passage inside the lower plates 23, 43, 63, and 83, and flow paths 23a, 43a, 63a, and 83a pass through the centers of the hot-contact points 27. Cooling unit of a semiconductor wafer comprising a; The method of claim 1, The flow path (23a) is a cooling unit of the semiconductor wafer, characterized in that the supply port (23b) and the discharge port (23c) has a 'S' shape so as to be provided facing each other around the lower plate (23). The method of claim 1, The flow path (43a) is a cooling unit of the semiconductor wafer, characterized in that the supply port (43b) and the discharge port (43c) has a 'Y' shape so as to be provided adjacent to each other on the peripheral side of the lower plate (43). The method of claim 1, The flow path (63a) is characterized in that the supply port (63b) and the discharge port (63c) is formed so as to form an 'S' shape inside the edge portion past the edge portion so as to face each of the periphery of the lower plate (63). Cooling unit of semiconductor wafer. The method of claim 1, The flow path (83a) is characterized in that the supply port (83b) and the discharge port (83c) is formed so as to be adjacent to each other on one side around the lower plate 83 to form a 'U' shape in the inner edge portion through the edge portion. Cooling unit of semiconductor wafer