WO2009051288A1

WO2009051288A1 - Temperature control system for semiconductor manufacturing equipment

Info

Publication number: WO2009051288A1
Application number: PCT/KR2007/005642
Authority: WO
Inventors: Bong-Hyun Cho; Chang-Woo Eun; Hyun-Seok Choi; Sang-Gon Lee; Kwang-Myung Lee; In-Joo Lee; Yong-Ho Choi; Seong-Kuk An; Choul-Oh Park
Original assignee: Global Standard Technology Co., Ltd.; Samsung Electronics Co., Ltd.
Priority date: 2007-10-18
Filing date: 2007-11-09
Publication date: 2009-04-23
Also published as: JP2011501429A; KR100925236B1; KR20090039420A; JP4956672B2; US20100206519A1

Abstract

A temperature control system for semiconductor manufacturing equipment is disclosed, which can properly cool a process chamber adopted in the semiconductor manufacturing equipment such as a wafer etching device. The temperature control system for semiconductor manufacturing equipment includes a thermocline for cooling heat transfer fluid accommodated therein through a heat exchange with a heat exchanger and storing heat energy, a supply line for controlling the temperature of the heat transfer fluid in the thermocline through a heater and supplying the heat transfer fluid with a proper temperature to a process device, a recovery line for forwarding the heat transfer fluid having passed through the process device to the thermocline, and a bypass for forwarding a part of the heat transfer fluid passing through the recovery line to the supply line through the heater.

Description

TEMPERATURE CONTROL SYSTEM FOR SEMICONDUCTOR MANUFACTURING

EQUIPMENT

Technical Field

The present invention relates to semiconductor manufacturing equipment, and more particularly to a temperature control system for semiconductor manufacturing equipment, which can properly cool a process chamber adopted in the semiconductor manufacturing equipment such as a wafer etching device.

Background Art Generally, semiconductor devices and semiconductor chips are manufactured by processing a wafer formed of silicone using semiconductor equipment. That is, in order to manufacture the semiconductor device or semiconductor chip, a wafer is typically processed through a series of semiconductor processes such as lithography, chemical or physical deposition, plasma etching, and so forth.

The quality of the semiconductor device or semiconductor chip may differ depending on variables such as the quality of a wafer, a wafer processing method, and so forth. One of important variables in manufacturing the semiconductor device is the temperature of a wafer surface. If the surface temperature of the wafer is not uniform, the etching rate of the wafer surface may differ. Accordingly, by uniformly controlling the temperature of the wafer surface, a semiconductor device having a higher quality can be manufactured.

Typically, the adjustment of the surface temperature of the wafer is performed by adjusting the temperature of a wafer chuck on which the wafer is mounted. Generally, the temperature of the wafer chuck has been adjusted by flowing fluid of a constant temperature provided through a chiller or a heat exchanger into the wafer chuck. FIG. 1 illustrates the construction of a conventional temperature control system for semiconductor manufacturing equipment .

According to the conventional temperature control system for semiconductor manufacturing equipment as illustrated in FIG. 1, cooling water or coolant that flows through lines Ll and L2 transfers low-temperature heat energy to coolant existing in a reservoir 2 through a heat exchanger 1 to cool the coolant, and then the cooled coolant in the reservoir 2, which is pumped by a pump 3, is supplied to a process device 4, i.e., a wafer chuck, connected to the reservoir 2 through the lines L3 and L4 to lower the temperature of the wafer chuck.

However, the conventional temperature control system for semiconductor manufacturing equipment having the above- described construction requires a large amount of electricity in controlling the process temperature, and this causes a large amount of energy to be consumed with the heat efficiency lowered. Further, since the conventional temperature control system controls a large amount of fluid, it takes a lot of time for reaching a desired temperature of the wafer chuck, and the speed to cope with the load is lowered. Furthermore, in the case of the general semiconductor manufacturing equipment, the temperature control system as illustrated in FIG. 1 should be provided for each process device to control the temperature of the process device, and this causes the increase of installation cost and scale of the temperature control system.

Disclosure Technical Problem

The present invention has been made in view of the foregoing problems, and it is an object of the present invention to improve the structure of a temperature control system for semiconductor manufacturing equipment so as to improve the energy efficiency of the semiconductor manufacturing equipment. It is another object of the present invention to improve the structure of a temperature control system for semiconductor manufacturing equipment so that the temperature of a heat transfer fluid being supplied to a process chamber of a process device can be promptly controlled at a desired temperature level.

It is still another object of the present invention to improve the structure of a temperature control system for semiconductor manufacturing equipment so that the temperatures of several process devices can be controlled using one temperature control system.

Technical Solution In order to achieve the above objects, in one aspect of the present invention, there is provided a temperature control system for semiconductor manufacturing equipment, which includes a thermocline for cooling heat transfer fluid accommodated therein through a heat exchange with a heat exchanger and storing heat energy; a supply line for controlling the temperature of the heat transfer fluid in the thermocline through a heater and supplying the heat transfer fluid with a proper temperature to a process device; a recovery line for forwarding the heat transfer fluid having passed through the process device to the thermocline; and a bypass for forwarding a part of the heat transfer fluid passing through the recovery line to the supply line through the heater. ^{^}

In another aspect of the present invention, there is provided a temperature control system for semiconductor manufacturing equipment, which includes a circulation line for supplying heat transfer fluid to a process device and then recovering the supplied heat transfer fluid; a thermocline for cooling the heat transfer fluid accommodated therein through a heat exchange with a heat exchanger, storing heat energy, receiving a part of the heat transfer fluid circulating through the circulation line, and then supplying the part of the heat transfer fluid accommodated therein to the circulation line; and a heater for controlling a temperature of the heat transfer fluid being supplied to the process device through the circulation line at a proper temperature level. The temperature control system according to embodiments of the present invention may further include a proportional control valve for controlling a flow of the heat transfer fluid so that a flow rate of the heat transfer fluid flowing into the thermocline through the process device and a flow rate of the heat transfer fluid being discharged to be supplied from the thermocline to the process device substantially coincide with each other.

The thermocline may include a phase change material (PCM) pipe for storing thermal energy using a PCM. The temperature control system according to embodiments of the present invention may further include a plurality of process devices connected to the thermocline so that the thermocline supplies the heat transfer fluid to the respective process devices. The temperature control system according to embodiments of the present invention may further include an auxiliary bypass for supplying to the heater the part of the heat transfer fluid being supplied to the process device through the heater.

Advantageous Effects

According to the temperature control system for semiconductor manufacturing equipment according to the present invention as constructed above, the heat transfer fluid to be supplied to the process device is cooled by the thermocline using the thermal storage and latent heat, a small amount of heat transfer fluid flowing through the supply line is heated to a desired process temperature by the heater, and the heat of the heat transfer fluid being recovered to the thermocline through the process device is used to control the temperature of the heat transfer fluid being supplied to the process device. Accordingly, the temperature control system for semiconductor manufacturing equipment according to the present invention has a higher heat efficiency than that of the general temperature control system.

In addition, since the temperature control system according to the present invention controls the temperature of only a small amount of heat transfer fluid, it can promptly cope with a required load.

In addition, according to the temperature control system according to the present invention, several process devices can be connected to one thermocline. Accordingly, the temperatures of the several process devices can be controlled using the heat transfer fluid stored in the thermocline, and thus the installation cost and scale can be reduced.

Brief Description of the Drawings

The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:

FIG. 1 is a block diagram schematically illustrating the construction of a conventional temperature control system for semiconductor manufacturing equipment;

FIG. 2 is a block diagram schematically illustrating the construction of a temperature control system for semiconductor manufacturing equipment according to a first embodiment of the present invention; FIG. 3 is a block diagram schematically illustrating the construction of a temperature control system for semiconductor manufacturing equipment according to a second embodiment of the present invention;

FIG. 4 is a block diagram schematically illustrating the construction of a temperature control system for semiconductor manufacturing equipment according to a third embodiment of the present invention; and

FIG. 5 is a block diagram schematically illustrating the construction of a temperature control system for semiconductor manufacturing equipment according to a fourth embodiment of the present invention.

Best: Mode

Reference will now be made in detail to a chiller system for semiconductor manufacturing equipment according to the preferred embodiments of the present invention with reference to the accompanying drawings.

FIG. 2 illustrates the construction of a temperature control system for semiconductor manufacturing equipment according to a first embodiment of the present invention. Hereinafter, the temperature control system for semiconductor manufacturing equipment according to the first embodiment of the present invention will be described with reference to FIG. 2.

As illustrated in FIG. 2, a thermocline 100 cools heat transfer fluid accommodated therein by exchanging heat with a heat exchanger 10. In addition, the thermocline 100 stores therein the heat-exchanged energy. For this, in the thermocline 100, a phase change material (PCM) pipe 110 is provided to store the heat-exchanged energy in a PCM. Since the thermal storage technique using the PCM is well known, further description thereof will be omitted. In the temperature control system for semiconductor manufacturing equipment according to the first embodiment of the present invention, the heat exchanger 10 that exchanges heat with the thermocline 100, as illustrated in FIG. 2, may be provided with an evaporator 10 having a cooling cycle. The heat exchanger 10, i.e., the evaporator, is connected in order to a compressor 20, a condenser 30, and an expander 40. Coolant in the heat exchanger 10 passes in order through the compressor 20, the condenser 30, and the expander 40, and then is returned to the heat exchanger 10, i.e., the evaporator.

The compressor 20 compresses a low-pressure gaseous coolant into a high-temperature high-pressure gaseous coolant, and the condenser 30 condenses the compressed high- temperature high-pressure gaseous coolant into a low- temperature liquid coolant by making the high-temperature high-pressure gaseous coolant exchange heat with an outside. In order to cool the coolant in the condenser 30, cooling water is supplied to the condenser 30. The liquid coolant having condensed through the condenser 30 is expanded through the expander 40, and then is gasified through the heat exchanger 10, i.e., the evaporator. Since the coolant absorbs heat from the heat exchanger 10 when it is gasified in the heat exchanger 10, the heat exchanger 10 is abruptly- cooled. Accordingly, the thermocline 100 cools the heat transfer fluid accommodated therein by exchanging heat with the cooled heat exchanger 10, and then stores therein the heat-exchanged energy using the PCM pipe 110. Then, the heat transfer fluid accommodated in the thermocline 100 is supplied to a process device 510, i.e., a wafer chuck, of the semiconductor manufacturing equipment to properly maintain the temperature of a wafer. This process will be described in more detail with reference to FIG. 2. The thermocline 100 and the process device 510 are connected through a supply line 200 and a recovery line 300. The supply line 200 supplies the heat transfer fluid in the thermocline 100 to the process device 510, and the recovery line 300 recovers and forwards the heat transfer fluid, which has been used to control the temperature of the wafer in the process device 510, to the thermocline 100. In the supply line 200, as illustrated in FIG. 2, a pump 220 for pumping and forwarding the heat transfer fluid to the process device 510 may be installed.

In the supply line 200, a pressure gauge 230 for measuring the pressure of the heat transfer fluid being supplied to the process device 510 through the supply line 200 may be installed, and in the recovery line 300, a flow meter 320 for measuring the flow rate of the heat transfer fluid flowing in the recovery line 300 may be installed. The amount of heat transfer fluid, which is supplied to the process device 510 through a valve provided in the supply line 200, can be controlled based on data measured by the pressure gauge 230 and the flow meter 320.

As illustrated in FIG. 2, a heater 210 is installed on the supply line 200. The heater 210 serves to keep the temperature of the heat transfer fluid to be supplied to the process device 510 at a proper temperature level and to adjust the process temperature by exchanging heat with the heat transfer fluid being supplied to the process device 510. Here, the process temperature of the heat transfer fluid being supplied to the process device is kept in the range of about -30°C to 180⁰C, depending on the kind and characteristic of the process.

In order to maintain the heat transfer fluid being supplied to the process device 510 at a proper temperature, i.e., the process temperature, the heater 210 does not heat the whole heat transfer fluid stored in the thermocline 100, but heats only a relatively small amount of heat transfer fluid flowing through the supply line 200. Accordingly, the energy efficiency is improved. On the other hand, the whole amount of heat transfer fluid flowing to the recovery line 300 through the process device 510 is not recovered to the thermocline 100, but a part of the heat transfer fluid bypasses the thermocline 100 and is forwarded to the heater 210 installed on the supply line 200. For this, a bypass 410 is connected to the supply line 200 and the recovery line 300. Accordingly, the bypass 410, the supply line 200, and the recovery line 300 form one circulation line, and the heat transfer fluid is circulated along the formed circulation line to be supplied to and recovered from the process device 510.

The remainder of the heat transfer fluid not flowing into the bypass 410 is recovered to the thermocline 100 through the recovery line 300. Also, a cold heat transfer fluid, the amount of which corresponds to the amount of the heat transfer fluid recovered to the thermocline 100, is supplemented to the supply line 200. The heat transfer fluid flowing into the supply line 200 through the bypass 410 and the heat transfer fluid supplemented to the supply line 200 are heated up to the process temperature by the heater 210, and then is supplied to the process device 510.

On the recovery line 300 between the bypass 410 and the thermocline 100, as illustrated in FIG. 2, a proportional control valve 310 may be installed. The proportional control valve 310 serves as an actual control valve. When a specified amount of heat transfer fluid normally circulating is forwarded to the thermocline 100, the low-temperature heat transfer fluid as much as the amount of heat transfer fluid being forwarded flows into the thermocline 100 to lower the temperature of the heat transfer fluid circulating in the thermocline 100 to a desired temperature. In this case, the proportional control valve 310 serves to control the temperature of the wafer in the process device 510 using the heat transfer fluid by adjusting the recovery rate and new supply rate of the circulating heat transfer fluid.

The proportional control valve 310 controls the flow of the heat transfer fluid so that the flow rate of the heat transfer fluid flowing into the thermocline 100 through the process device 510 and the flow rate of the heat transfer fluid being discharged to be supplied from the thermocline 100 to the process device 510 substantially coincide with each other. Accordingly, the thermocline 100 supplies to the circulation line the heat transfer fluid as much as the amount of heat transfer fluid being recovered through the recovery line 300, under the control of the proportional control valve 310.

As illustrated in FIG. 2, an auxiliary bypass 420 may be connected to the supply line 200 and the bypass 410. The auxiliary bypass 420 forwards to the bypass 410 a part of the heat transfer fluid being heated to the process temperature by the heater 210 and then supplied to the process device 510. The auxiliary bypass 420 facilitates the control of the pressure and flow rate of the heat transfer fluid being pumped by the pump 220 and forwarded to the process device 510 to facilitate the repair and maintenance of the process device 510. Hereinafter the operation of the temperature control system for semiconductor manufacturing equipment according to the first embodiment of the present invention will be described. If the compressor 20 is operated, the heat exchanger 10 exchanges heat with the thermocline 100. At an initial operation stage of the temperature control system, since the compressor 20 is operated at a high speed, the heat transfer fluid in the thermocline 100 is rapidly cooled, and the PCM pipe 110 stores the cooled heat transfer fluid. After a specified time elapses, the heat energy accumulated in the PCM pipe 110 cools the heat transfer fluid in the thermocline 100 even though the output of the compressor 20 is lowered. Accordingly, the temperature control system according to the present invention has a higher heat efficiency than that of the conventional temperature control system.

The heat transfer fluid in the thermocline 100 is heated to the process temperature by the heater 210, and then is supplied to the process device 510. The heat transfer fluid supplied to the process device 510 is used to control the temperature of the wafer, and the heat transfer fluid having a heightened temperature flows into the recovery line 300. A part of the heat transfer fluid flowing into the recovery line 300 is forwarded to the heater 210 through the bypass 410, while the remainder thereof is recovered to the thermocline 100. The thermocline 100 forwards to the heater 210 the cold heat transfer fluid as much as the amount of the recovered heat transfer fluid under the control of the proportional control valve 310.

The heat transfer fluid having a relatively high temperature that is discharged from the bypass and the heat transfer fluid having a relatively low temperature that is discharged from the thermocline 100 are mixed, and the mixed heat transfer fluid is heated to a proper process temperature by the heater 210. Accordingly, the temperature control system according to the present invention has a higher heat efficiency than that of the conventional temperature control system.

In the embodiment of the present invention as described above, it is exemplified that the temperature control system according to the present invention is applied to one process device 510. However, the present invention is not limited thereto. The temperature control system according to the present invention may be applied to several process devices 510 as illustrated in FIG, 3 illustrating the construction of a temperature control system for semiconductor manufacturing equipment according to a second embodiment of the present invention.

As illustrated in FIG. 3, according to the temperature control system according to the second embodiment of the present invention, one thermocline 100 is connected to respective process devices 510 and 520, and supplies the heat transfer fluid to the respective process devices 510 and 520. That is, the respective process devices 510 and 520 are connected to the thermocline 100, and receive the supply of the heat transfer fluid from the thermocline 100. Here, since the respective process devices 510 and 520 connected to the thermocline 100 have the same structure, and the heat transfer fluid circulating structure on the lines connected to the respective process devices 510 and 520 is the same as that described with reference to FIG. 2, repeated description thereof will be omitted.

In FIGS. 2 and 3, it is exemplified that the heat exchanger 10 that exchanges heat with the thermocline 100 is composed of the evaporator having a cooling cycle. However, the present invention is not limited thereto. As illustrated in FIGS. 4 and 5, the heat exchanger of the temperature control system according to the present invention may be constructed to receive the supply of cooling water separately and to exchange heat with the thermocline. Here, methods of cooling the heat exchanger 10 using a cooling cycle or cooling water may be properly selected according to the process temperature of the heat transfer fluid. For example, in the case of lowering the temperature of the heat transfer fluid from 3O⁰C to 2O⁰C, it is preferable to cool the heat exchanger 10 using the cooling cycle rather than using the cooling water. In the case of lowering the temperature of the heat transfer fluid below zero degree, it is preferable to cool the heat exchanger using the cooling cycle. By contrast, in the case of lowering the temperature of the heat transfer fluid from 100⁰C to 40⁰C, it is enough to cool the heat exchanger 10 using the cooling water.

In FIGS. 4 and 5 illustrating the temperature control systems according to the third and fourth embodiments of the present invention, the remaining parts except for the structure of the heat exchanger 10a exchanging heat with the thermocline 100 and the structure of the cooling device connected to the heat exchanger 10a are the same as those as described with reference to FIGS. 2 and 3, and thus repeated description thereof will be omitted.

Industrial Applicability

As can be seen from the foregoing, the chiller system for semiconductor manufacturing equipment according to the present invention has the following effects.

Since a small amount of heat transfer fluid flowing through the supply line is heated to a desired process temperature by the heater and the heat of the heat transfer fluid being recovered to the thermocline through the process device is used to control the temperature of the heat transfer fluid being supplied to the process device, the temperature control system for semiconductor manufacturing equipment according to the present invention has a higher heat efficiency than that of the general temperature control system.

The temperature control system according to the present invention controls the temperature of only a small amount of heat transfer fluid, and thus can promptly cope with a required load.

According to the temperature control system according to the present invention, since several process devices can be connected to one thermocline, the temperatures of the several process devices can be controlled using the heat transfer fluid stored in the thermocline, and thus the installation cost and scale can be reduced.

While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiment and the drawings. On the contrary, it is intended to cover various modifications and variations within the spirit and scope of the appended claims.

Claims

1. A temperature control system for semiconductor manufacturing equipment , comprising: a thermocline for cooling heat transfer fluid accommodated therein through a heat exchange with a heat exchanger and storing heat energy; a supply line for controlling the temperature of the heat transfer fluid in the thermocline through a heater and supplying the heat transfer fluid with a proper temperature to a process device; a recovery line for forwarding the heat transfer fluid having passed through the process device to the thermocline; and a bypass for forwarding a part of the heat transfer fluid passing through the recovery line to the supply line through the heater.

2. A temperature control system for semiconductor manufacturing equipment, comprising: a circulation line for supplying heat transfer fluid to a process device and then recovering the supplied heat transfer fluid; a thermocline for cooling the heat transfer fluid accommodated therein through a heat exchange with a heat exchanger, storing heat energy, receiving a part of the heat transfer fluid circulating through the circulation line, and then supplying the part of the heat transfer fluid accommodated therein to the circulation line; and a heater for controlling a temperature of the heat transfer fluid being supplied to the process device through the circulation line at a proper temperature level.

3. The temperature control system of claim 1 or 2, further comprising a proportional control valve for controlling a flow of the heat transfer fluid so that a flow rate of the heat transfer fluid flowing into the thermocline through the process device and a flow rate of the heat transfer fluid being discharged to be supplied from the thermocline to the process device substantially coincide with each other.

4. The temperature control system of claim 1 or 2, wherein the thermocline comprises a phase change material

(PCM) pipe for storing thermal energy using a PCM.

5. The temperature control system of claim 1 or 2, further comprising a plurality of process devices connected to the thermocline so that the thermocline supplies the heat transfer fluid to the respective process devices.

6. The temperature control system of claim 1 or 2, further comprising an auxiliary bypass for supplying to the heater the part of the heat transfer fluid being supplied to the process device through the heater.