JP2007294887A - Substrate cooling device and structure cooling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate cooling device which can obtain high cooling efficiency and keep an even temperature distribution in the plane of a substrate during cooling. <P>SOLUTION: The steam of a coolant is compressed into superheated steam by a compressor 20 and then is cooled and condensed by a capacitor 30, so that a supercooled liquid of the coolant is obtained. The supercooled liquid is expanded and decompressed by passing through an expansion valve 40, so that a mixed phase of the saturated liquid and saturated steam of the coolant is obtained. Next, the mixed fluid is separated into a vapor phase and a liquid phase by a liquid separator 50, and only the saturated liquid of the coolant is supplied to a cold plate 10. The hollow portion of the cold plate 10 is filled only with the saturated liquid of the coolant. It is thus possible to obtain high cooling efficiency sufficiently using boiling heat transfer and keep an even temperature distribution in the plane of the plate because the saturated liquid does not have a pressure difference. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention provides a substrate cooling device and a cooling plate for cooling a thin plate-like electronic component substrate (hereinafter simply referred to as “substrate”) such as a glass substrate for a liquid crystal display device or a semiconductor wafer placed on a cooling plate to a predetermined temperature. The present invention relates to a structure cooling apparatus for cooling a structure to be mounted to a predetermined temperature.

  In general, a process for manufacturing a flat panel display or a color filter includes a heat treatment process for a glass substrate. In addition, a semiconductor device manufacturing process includes a number of semiconductor wafer heat treatment processes. Usually, in the heat treatment process for a substrate, a heat treatment for heating the substrate to a predetermined heating temperature and a cooling treatment for cooling the heated substrate are often performed as a pair.

  Conventionally, as a method for cooling a substrate, there are many methods in which a substrate is placed on a plate-like body maintained at a predetermined cooling temperature and cooled. For example, in Patent Documents 1 and 2, there is a technique in which a cooling liquid is supplied to the internal space of a plate-like body to maintain the plate-like body at a cooling temperature, and a substrate is placed on the plate-like body to cool it. It is disclosed. Patent Document 3 discloses a technique for cooling a substrate by providing a flow path inside a plate-like body on which a substrate is placed and flowing a cooling liquid through the flow path to lower the plate-like body to a cooling temperature. Has been. In any of these methods, a cooling liquid such as ethylene glycol is cooled to a predetermined temperature using a cooler, and the temperature-controlled cooling liquid is allowed to flow inside the plate-like body. When the substrate after the heat treatment is placed on the plate-like body, heat is transferred from the substrate to the coolant via the plate-like body, and the temperature of the coolant rises at the same time as the cooling of the substrate proceeds. Since the heated coolant cannot cool the substrate to the target cooling temperature, new coolant is continuously supplied from the cooler to the plate-like body, and the heated coolant is returned to the cooler again. Cooling to a predetermined temperature is performed. That is, the cooling liquid is circulated between the cooler and the plate-like body so that the plate-like body is always maintained at a constant cooling temperature.

JP 2001-209033 A JP 2002-158245 A JP-A-64-46930

  In the conventional cooling process as described above, heat transfer from the high-temperature substrate to the coolant via the plate-like body is the basic principle of substrate cooling, but the cooling disclosed in Patent Documents 1 to 3 The heat transfer in the process is convective heat transfer without any phase change (more precisely, forced convection heat transfer that is forced to flow by a pump or the like). Such forced convection heat transfer has a problem that it is difficult to obtain good heat transfer efficiency.

  Further, in the cooling process of a substrate for precision electronic devices such as a glass substrate, it is required to make the in-plane temperature distribution of the substrate as uniform as possible. However, in the above-described conventional cooling process, since the cooling liquid is caused to flow inside the plate-like body, a delicate temperature difference is inevitably generated between the inlet side temperature and the outlet side temperature. That is, during the cooling process of the substrate, the coolant temperature on the inlet side to the plate-like body is the temperature cooled by the cooler, but the coolant temperature on the outlet side slightly increases due to heat transfer from the substrate. is doing. For this reason, there is a problem that the temperature in the vicinity of the exit side is slightly higher than the vicinity of the entrance side of the plate-like body, and as a result, the in-plane temperature distribution uniformity of the substrate during the cooling process is impaired.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a substrate cooling apparatus capable of obtaining good cooling efficiency and maintaining the in-plane temperature distribution uniformity of the substrate being cooled. And

  Another object of the present invention is to provide a structure cooling apparatus that can obtain good cooling efficiency and can maintain the temperature distribution uniformity of the structure being cooled.

  In order to solve the above-mentioned problems, the invention of claim 1 is a substrate cooling apparatus for cooling a substrate placed on a cooling plate to a predetermined temperature, wherein a hollow portion is provided inside the cooling plate, and a coolant is provided in the hollow portion. Saturated liquid is filled.

  According to a second aspect of the present invention, in the substrate cooling apparatus according to the first aspect of the present invention, the cooling plate is provided at the lowest height position of the hollow portion, and a saturated liquid of refrigerant is supplied to the hollow portion. A liquid supply port; and a gas discharge port that is provided at the highest height position of the hollow portion and discharges the vapor of the refrigerant generated from the saturated liquid of the refrigerant boiling in the hollow portion.

  Further, the invention of claim 3 is the substrate cooling apparatus according to the invention of claim 1, wherein the cooling plate has a liquid supply port for supplying a saturated liquid of the refrigerant to the hollow portion, and the refrigerant boiled in the hollow portion. A gas discharge port that discharges the vapor of the refrigerant generated from the saturated liquid, and the hollow portion communicates with the liquid supply port and extends along the first direction, and the gas discharge port. Communicating with the outlet, arranged in parallel between the supply-side flow path and the discharge-side flow path along the first direction, the discharge-side flow path provided in parallel with the supply-side flow path, And a plurality of communication channels that connect the supply channel and the discharge channel.

  According to a fourth aspect of the present invention, in the substrate cooling apparatus according to the third aspect of the present invention, the first direction is a horizontal direction, and the discharge-side flow path is provided at a position higher than the supply-side flow path. .

  Further, the invention of claim 5 is the substrate cooling apparatus according to claim 3 or claim 4, wherein the length of the communication channel is set to the saturation temperature of the refrigerant due to pressure loss when the generated refrigerant vapor flows. The reference length is set such that the fluctuation is not more than a predetermined range.

  According to a sixth aspect of the present invention, in the substrate cooling apparatus according to the fifth aspect of the present invention, the reference length is set such that a variation in the saturation temperature is ± 1 ° C. or less.

  The invention of claim 7 is the substrate cooling apparatus according to claim 5 or 6, wherein the liquid supply port, the gas discharge port, the supply side flow path, the discharge side flow are provided in the cooling plate. A plurality of unit supply / discharge systems having a path and a plurality of communication channels of the reference length are provided in parallel along a second direction orthogonal to the first direction.

  The invention according to claim 8 is the substrate cooling apparatus according to claim 5 or claim 6, wherein the liquid supply port, the gas discharge port, the supply side flow channel, the discharge side flow channel, and the reference length. A plurality of cooling plates having a plurality of connecting flow paths are provided side by side along a second direction orthogonal to the first direction.

  According to a ninth aspect of the present invention, in the substrate cooling apparatus according to any one of the second to eighth aspects, the compressor that compresses the vapor of the refrigerant and the superheated vapor of the refrigerant generated by the compressor are provided. A liquid phase is a mixed phase of a condenser to be condensed, an expansion valve for expanding a saturated liquid or a supercooled liquid of the refrigerant generated by the condenser, and a saturated liquid and a saturated vapor of the refrigerant generated by the expansion valve. And a gas-liquid separator that separates into a gas phase, and only the saturated liquid of the refrigerant separated by the gas-liquid separator is supplied to the hollow portion from the liquid supply port.

  Further, the invention of claim 10 is the substrate cooling apparatus according to the invention of claim 9, wherein the refrigerant vapor generated from the saturated liquid of the refrigerant boiling in the hollow portion is sent from the gas outlet to the gas-liquid separator. I am returning.

  The invention of claim 11 is the substrate cooling apparatus according to claim 9 or claim 10, wherein a temperature measuring unit for measuring the temperature of the cooling plate, and a refrigerant from the gas-liquid separator to the compressor. A pressure regulating valve interposed in a pipe for supplying steam, and the pressure regulating valve based on the temperature of the cooling plate measured by the temperature measuring unit so that the temperature of the cooling plate becomes the predetermined temperature. Temperature control means for adjusting the vapor pressure in the gas-liquid separator by controlling the gas.

  According to a twelfth aspect of the present invention, in the substrate cooling apparatus according to any of the ninth to eleventh aspects of the invention, the liquid level of the saturated liquid of the refrigerant stored in the gas-liquid separator is detected. Based on the detection result of the liquid level detection unit and the liquid level detection unit, the compressor operates so that the liquid level of the saturated liquid of the refrigerant stored in the gas-liquid separator is constant. Level control means for controlling.

  According to a thirteenth aspect of the present invention, in the structure cooling apparatus for cooling a structure to which a cooling plate is mounted to a predetermined temperature, a hollow portion is provided inside the cooling plate, and a saturated liquid coolant is provided in the hollow portion. It is full.

  According to the first aspect of the present invention, since the saturated liquid of the refrigerant is filled in the hollow portion provided inside the cooling plate, good cooling efficiency can be obtained by sufficiently utilizing the boiling heat transfer of the saturated liquid, and the saturated liquid It is possible to make the temperature distribution in the plate surface uniform by preventing the pressure difference from being generated, and to maintain the in-plane temperature distribution uniformity of the substrate being cooled.

  According to the second aspect of the present invention, the cooling plate is provided at the lowest height position of the hollow portion, the liquid supply port for supplying the saturated liquid of the refrigerant to the hollow portion, and the highest height position of the hollow portion. And a gas discharge port for discharging the vapor of the refrigerant generated from the saturated liquid of the refrigerant boiled in the hollow portion, so that the generated vapor of the refrigerant smoothly escapes from above and continuously enters the hollow portion. The saturated liquid can be maintained in a quietly filled state, and the effect of claim 1 can be reliably obtained.

  According to the invention of claim 3, the liquid supply port that supplies the refrigerant saturated liquid to the hollow portion and the gas that discharges the refrigerant vapor generated from the refrigerant saturated boiling in the hollow portion to the cooling plate. A discharge port provided in parallel with the supply side flow path and the gas discharge port, which communicates with the liquid supply port in the hollow portion and extends along the first direction. A plurality of connecting flow paths that are arranged between the supply flow path and the discharge flow path along the first direction and that connect the supply flow path and the discharge flow path. Therefore, the saturated liquid of the refrigerant can be filled uniformly and quietly inside the cooling plate, and the effect of claim 1 can be obtained with certainty.

  Further, according to the invention of claim 4, since the discharge side flow path is provided at a position higher than the supply side flow path, the generated refrigerant vapor smoothly escapes from above and is continuously supplied into the hollow portion. The saturated liquid can be maintained in a gently filled state, and the effect of claim 1 can be reliably obtained.

  Further, according to the invention of claim 5, since the length of the communication flow path is set to a reference length in which the variation of the saturation temperature of the refrigerant due to the pressure loss when the vapor of the refrigerant flows flows is a predetermined length or less, the plate surface The temperature distribution inside can be made uniform with high accuracy.

  In addition, according to the invention of claim 6, since the reference length is set to such a length that the variation of the saturation temperature is ± 1 ° C. or less, the temperature distribution in the plate surface can be made uniform with high accuracy.

  According to the invention of claim 7, the cooling plate is provided with a unit supply / discharge system having a liquid supply port, a gas discharge port, a supply side flow channel, a discharge side flow channel, and a plurality of communication channels of a reference length. Since a plurality of the substrates are arranged in parallel along the second direction perpendicular to the first direction, even a large substrate can be cooled without impairing the temperature distribution uniformity.

  According to the invention of claim 8, the cooling plate having a liquid supply port, a gas discharge port, a supply side flow channel, a discharge side flow channel, and a plurality of communication flow channels having a reference length is orthogonal to the first direction. Since a plurality of the substrates are arranged in parallel along the second direction, even a large substrate can be cooled without impairing temperature distribution uniformity.

  Further, according to the invention of claim 9, since only the refrigerant saturated liquid separated from the mixed phase of the refrigerant saturated liquid and the saturated vapor is supplied to the hollow portion of the cooling plate by the gas-liquid separator, The effect of claim 1 can be obtained with certainty.

  According to the invention of claim 10, since the vapor of the refrigerant generated from the saturated liquid of the refrigerant boiling in the hollow portion of the cooling plate is returned to the gas-liquid separator, the refrigerant can be circulated and used. .

  According to the eleventh aspect of the invention, based on the temperature of the cooling plate measured by the temperature measuring unit, the pressure regulating valve is controlled so that the temperature of the cooling plate becomes a predetermined temperature, so that the inside of the gas-liquid separator is Since the vapor pressure is adjusted, a stable substrate cooling process can be performed with the cooling plate temperature kept constant.

  According to the invention of claim 12, based on the detection result of the liquid level detector, the compressor level is adjusted so that the liquid level of the saturated liquid of the refrigerant stored in the gas-liquid separator is constant. Since the operation is controlled, it is possible to continuously supply the saturated liquid of the refrigerant to the cooling plate.

  According to the invention of claim 13, since the saturated liquid of the refrigerant is filled in the hollow portion provided inside the cooling plate, a good cooling efficiency sufficiently utilizing the boiling heat transfer of the saturated liquid can be obtained, A pressure difference is prevented from occurring in the saturated liquid, the temperature distribution in the plate surface is made uniform, and the temperature distribution uniformity of the structure being cooled can be maintained.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a configuration of a cooling system of a substrate cooling apparatus according to the present invention. In the figure, a solid line indicates a flow of a fluid (liquid phase, gas phase, or a mixed phase thereof), and a dotted line indicates an electric signal flow.

  The substrate cooling apparatus 1 of the present embodiment cools the glass substrate W placed on the cold plate 10 to a predetermined cooling temperature using a refrigerant. The refrigerant used in the substrate cooling apparatus 1 of the present embodiment is Freon (R134a). Note that chlorofluorocarbon (R134a) is not a so-called specific chlorofluorocarbon, which is supposed to destroy the ozone layer, but an alternative chlorofluorocarbon having an ozone depletion coefficient of “0”.

  In addition to the cold plate 10, the substrate cooling device 1 mainly includes a compressor 20, a condenser (condenser) 30, an expansion valve 40, and a gas-liquid separator 50. The compressor 20 is connected to the condenser 30 and the evaporator (evaporator) 70 through a pipe. The compressor 20 sucks the refrigerant vapor from the evaporator 70 and compresses the vapor to increase the pressure and send it to the condenser 30. It has a function to supply. The compressor 20 is a volumetric compressor (such as a reciprocating type) that compresses and compresses the volume of the sucked steam, or a centrifugal compression that imparts a speed to the steam with an impeller that rotates at high speed, and converts the pressure into pressure to compress it. Various known compressors such as a compressor can be used.

  The condenser 30 is connected to the compressor 20 and the expansion valve 40 through a pipe, and has a function of receiving the refrigerant vapor fed from the compressor 20 and condensing it to liquefy it. When the normal process is in progress, the refrigerant liquid generated by the capacitor 30 is sent to the expansion valve 40. As the capacitor 30, a known condenser such as a water-cooled condenser, an air-cooled condenser, or an evaporative condenser can be used.

  The expansion valve 40 is connected in communication with the condenser 30 and the gas-liquid separator 50 through piping, and the refrigerant liquid sent out from the condenser 30 is expanded and expanded to be sent out to the gas-liquid separator 50. The expansion valve 40 has a function of switching the flow rate through which the refrigerant passes, and can be switched in two stages of a large flow rate and a small flow rate.

  The gas-liquid separator 50 separates the refrigerant sent out from the expansion valve 40 into a gas phase and a liquid phase. The separated liquid phase of the refrigerant is stored below the gas-liquid separator 50, and the gas phase is accumulated above the gas-liquid separator 50. The gas-liquid separator 50 is provided with a level sensor 55, and the level sensor 55 detects the liquid level of the liquid phase of the refrigerant stored in the gas-liquid separator 50. As the level sensor 55, various known sensors such as an optical sensor can be used.

  The upper part of the gas-liquid separator 50 (that is, the part where the gas phase of the refrigerant is to be accumulated) is connected to the accumulator 60 through a pipe. The accumulator 60 is also a kind of gas-liquid separator. When the liquid phase is contained in the gas phase of the refrigerant sent out from the gas-liquid separator 50, the liquid phase is separated and only the gas phase is evaporated. To 70. In addition, a pressure regulating valve 80 is inserted in the middle of a piping path connecting the gas-liquid separator 50 and the accumulator 60. The pressure adjustment valve 80 can continuously adjust the pressure of the pipe line from the internal space of the gas-liquid separator 50 to the pressure adjustment valve 80.

  The evaporator 70 is connected in communication with the accumulator 60 and the compressor 20 via a pipe, and sends the refrigerant supplied from the accumulator 60 to the compressor 20 in a state of only a gas phase. If the compressor 20 sucks in a refrigerant containing an incompressible liquid phase, there is a risk of causing erosion (erosion) due to mist and causing a failure. Therefore, an accumulator is provided so that only the gas phase refrigerant can be fed into the compressor 20. 60 and an evaporator 70 are provided. In the substrate cooling apparatus 1 of the present embodiment, the refrigerant sent out from the gas-liquid separator 50 via the pressure regulating valve 80 is in principle a gas phase single phase, but it is assumed that the liquid phase is included for some reason. The accumulator 60 and the evaporator 70 are provided as insurance for preventing the liquid phase from being sucked into the compressor 20. Note that it is not always necessary to install both the accumulator 60 and the evaporator 70, and either one may be provided.

  FIG. 2 is a perspective view of the cold plate 10. FIG. 3 is a cross-sectional view taken along line VV in FIG. 2 showing the internal structure of the cold plate 10. In FIG. 2 and subsequent figures, an XYZ orthogonal coordinate system in which the Z-axis direction is the vertical direction and the XY plane is the horizontal plane is appropriately attached to clarify the directional relationship.

  The plate main body 11 of the cold plate 10 is a flat plate having a rectangular shape in plan view, and is formed of a metal having good heat conduction (in this embodiment, aluminum). The glass substrate W to be cooled is placed on the surface of the plate body 11. The surface of the plate body 11 is anodized to improve wear resistance and prevent peeling electrification.

  An inlet header 12 is fixed on the lower surface side of the plate body 11 along the X-axis direction. The inlet header 12 is a quadrangular prism-shaped member that is provided through the supply side flow path 12b along the center line. Both ends of the supply-side flow path 12b are open as liquid supply ports 12a. That is, the supply-side flow path 12b is a pipe line that communicates with the liquid supply port 12a and extends along the X-axis direction (first direction) that is the horizontal direction.

  An outlet header 13 is fixed to the side end surface of the plate body 11 along the X-axis direction. The outlet header 13 is a quadrangular prism-shaped member provided with a discharge-side channel 13b extending therethrough along the center line. Since the outlet header 13 is higher than the inlet header 12, the discharge side flow path 13b is provided at a position higher than the supply side flow path 12b. Both ends of the discharge side channel 13b are opened as gas discharge ports 13a. That is, the discharge side flow path 13b is a pipe line that communicates with the gas discharge port 13a and extends parallel to the supply side flow path 12b along the X-axis direction. The material of the inlet header 12 and the outlet header 13 may be the same material as that of the plate body 11.

  A plurality of communication channels 14 are arranged in parallel along the X-axis direction between the supply-side channel 12b and the discharge-side channel 13b. Each communication channel 14 is a fluid-passable conduit formed so as to extend along the Y-axis direction. One end of each of the plurality of communication channels 14 is connected to the supply-side channel 12b, and the other end is connected to the discharge-side channel 13b. As a result, a hollow portion constituted by the supply side flow path 12b, the discharge side flow path 13b, and the communication flow path 14 is formed inside the cold plate 10, and the liquid supply port 12a, the gas discharge port 13a, Are communicated via the supply-side flow path 12b, the discharge-side flow path 13b, and the communication flow path 14.

  The liquid supply ports 12a, which are openings at both ends of the supply-side flow path 12b, are connected to the lower part of the gas-liquid separator 50 (that is, the part where the liquid phase of the refrigerant is to be stored) through a pipe. On the other hand, the gas discharge port 13a which is an opening at both ends of the discharge side channel 13b is connected to the upper part of the gas-liquid separator 50 (the part where the gas phase of the refrigerant is to be accumulated) through a pipe. In addition, the piping which each connects the liquid supply port 12a and the gas discharge port 13a, and the gas-liquid separator 50 is provided so that it may not interfere with the conveyance robot for carrying in / out the glass substrate W to / from the cold plate 10. Of course.

  With such a configuration, the liquid supply port 12a becomes an opening provided at the lowest height position in the direction (Z direction) perpendicular to the mounting surface of the glass substrate W in the hollow portion of the cold plate 10, and the gas-liquid separator The refrigerant liquid stored in 50 is supplied to the hollow portion through the liquid supply port 12a. The gas discharge port 13a is an opening provided at the highest height in the direction perpendicular to the mounting surface of the glass substrate W in the hollow portion of the cold plate 10, and the refrigerant vapor generated in the hollow portion is discharged from the gas. The gas is discharged from the outlet 13a to the gas-liquid separator 50.

  Returning to FIG. 1, a temperature sensor 19 is attached to the cold plate 10. The temperature sensor 19 measures the temperature near the surface of the cold plate 10. For the temperature sensor 19, for example, a thermocouple can be used.

  In addition to the above, the fluid path in the substrate cooling apparatus 1 is provided with a bypass pipe that branches from the pipe from the capacitor 30 to the expansion valve 40 and joins the pipe from the accumulator 60 to the evaporator 70. A bypass valve 85 is inserted in the middle of the bypass piping. The bypass valve 85 is closed during normal processing, and is opened when the temperature of the cold plate 10 drops abnormally beyond a predetermined setting range, and returns the refrigerant directly to the evaporator 70.

  As a control mechanism of the substrate cooling apparatus 1, a temperature controller 93 and a level controller 96 are provided in addition to a control unit 90 that manages the entire apparatus. These are all configured in the same manner as a normal computer equipped with a CPU and the like. The temperature controller 93 controls the pressure regulating valve 80 and the bypass valve 85 based on the temperature of the cold plate 10 measured by the temperature sensor 19. The level controller 96 controls the operation of the compressor 20 based on the liquid level in the gas-liquid separator 50 detected by the level sensor 55. Further, the control unit 90 controls the expansion valve 40 based on the operating state of the compressor 20. The specific control contents by these control mechanisms will be further described later.

  Next, the operation content in the substrate cooling apparatus 1 having the above configuration will be described. FIG. 4 is a Mollier diagram showing the state of the refrigerant. The vertical axis in FIG. 4 indicates pressure, and the horizontal axis indicates enthalpy. In the figure, the left side of the saturated liquid line L1 is the supercooled liquid phase, the right side of the saturated vapor line L2 is the superheated vapor phase, and the gap between the saturated liquid line L1 and the saturated vapor line L2 is It becomes a mixed phase. 4 indicates a critical point. Hereinafter, the description will be continued with reference to FIG.

  First, the refrigerant vapor sucked into the compressor 20 is the refrigerant superheated vapor shown in the state A, and is in the state of only the gas phase. The refrigerant vapor is compressed by the compressor 20 to become superheated vapor indicated by the state B. Assuming that the compression stroke by the compressor 20 is adiabatic compression (compression without heat flow between the refrigerant and the outside), the vapor of the refrigerant increases in pressure from the state A along the isentropic line and the temperature also increases. In the vicinity of the outlet of the compressor 20, the superheated steam in the state B is obtained. Of course, the superheated steam of the refrigerant shown in the state B is a gas phase single phase.

  The refrigerant superheated steam shown in the state B generated by the compressor 20 flows into the condenser 30, is cooled by the condenser 30, is condensed into a saturated liquid having a saturation temperature corresponding to the pressure in the state B, and is further supercooled. Thus, the supercooled liquid shown in state C is obtained. The supercooled liquid of the refrigerant shown in the state C is in a liquid phase only state. In addition, the capacitor | condenser 30 does not necessarily need to supercool a solvent, and may condense to a saturated liquid.

  The refrigerant supercooling liquid generated in the state C generated by the capacitor 30 flows to the expansion valve 40. If there is no heat exchange with the outside during the flow of the refrigerant liquid from the capacitor 30 to the expansion valve 40 and there is no pressure drop due to the flow, the refrigerant liquid immediately before flowing into the expansion valve 40 remains in the state C. Then, expansion occurs when the supercooled liquid of the refrigerant indicated by the state C passes through the expansion valve 40, and the refrigerant enters a mixed phase state indicated by the state D. When the supercooled liquid of the refrigerant passes through the expansion valve 40, heat does not enter and exit the refrigerant (adiabatic expansion), and the refrigerant simply expands and drops in pressure without any work. That is, the enthalpy of state C and the enthalpy of state D are equal.

  The refrigerant mixed phase indicated by the state D generated by passing through the expansion valve 40 is a mixture of the refrigerant saturated liquid indicated by the state E and the refrigerant saturated vapor indicated by the state F. . Such a refrigerant mixed phase is supplied from the expansion valve 40 to the gas-liquid separator 50, and in the gas-liquid separator 50, the liquid phase (saturated liquid in the state E) and the gas phase (saturated vapor in the state F) Separated. The separated saturated liquid of the refrigerant is stored below the gas-liquid separator 50, and the saturated vapor of the refrigerant is accumulated above the gas-liquid separator 50.

  The refrigerant saturated liquid stored in the gas-liquid separator 50 is supplied to the hollow portion in the cold plate 10 via the liquid supply port 12 a of the inlet header 12. Here, the pipe communicating with the liquid supply port 12a is connected to the lower part of the gas-liquid separator 50, and only the saturated liquid of the refrigerant separated by the gas-liquid separator 50 is supplied to the hollow part of the cold plate 10. Will be. In addition, since the liquid supply port 12a is provided at the lowest height position of the hollow portion of the cold plate 10, the saturated liquid of the refrigerant is introduced into the hollow portion from below, and the refrigerant saturated liquid is surely contained in the hollow portion. Will be charged.

  In the cooling system of the substrate cooling apparatus 1 of the present embodiment, the hollow portion in the cold plate 10 is simply filled with the saturated liquid of the refrigerant, and the saturated liquid is not flowing through the communication channel 14. The saturated liquid is a liquid in a limit state (critical state) where the liquid phase can be maintained. When heat is applied to the saturated liquid as much as possible, the temperature does not change and evaporation boiling starts. Therefore, when the glass substrate W after the heat treatment is placed on the cold plate 10 in which the saturated liquid is filled in the hollow portion, heat is transferred from the glass substrate W to the saturated liquid of the refrigerant, and the heat load causes the saturated liquid of the refrigerant. Boils immediately. The heat transfer here is a heat transfer from the solid wall surface of the cold plate 10 (more precisely, the inner wall surface of the connecting flow path 14) to the boiling refrigerant, and is referred to as boiling heat transfer.

  A feature of boiling heat transfer with such a phase change from the liquid phase to the gas phase is that it exhibits a higher heat transfer coefficient than convective heat transfer without phase change. For this reason, in the substrate cooling apparatus 1 of this embodiment, favorable cooling efficiency can be obtained and the cooling rate of the glass substrate W can be made high-speed.

  In addition, since the saturated liquid of the refrigerant is only filled in the hollow portion in the cold plate 10 and does not flow through the communication flow path 14, no pressure drop due to the fluid flow occurs. For this reason, the state of the refrigerant saturated liquid filled in the hollow portion of the cold plate 10 is uniform (state E in FIG. 4), and the temperature is also uniform. Therefore, even on the surface of the cold plate 10, there is no temperature difference from the vicinity of the inlet header 12 to the vicinity of the outlet header 13, and the in-plane temperature distribution uniformity of the glass substrate W during the cooling process is maintained with high accuracy. be able to.

  When a high-temperature glass substrate W is placed on the cold plate 10, the refrigerant vapor generated from the saturated liquid of the refrigerant boiled in the hollow portion by heat transfer from the glass substrate W is discharged from the gas outlet 13 a of the outlet header 13. To the gas-liquid separator 50. When the glass substrate W is not placed on the cold plate 10, only the saturated liquid of the refrigerant is filled in the hollow portion of the cold plate 10, and the thermal load is hardly applied to the saturated liquid. Only a very small amount of refrigerant vapor is discharged from the gas discharge port 13 a to the gas-liquid separator 50.

  Since the gas discharge port 13a is provided at the highest height position of the hollow portion of the cold plate 10, the vapor of the refrigerant generated in the hollow portion of the cold plate 10 is in the gas phase without requiring any special power. Due to the difference in specific gravity from the liquid phase, the gas will naturally escape from the gas outlet 13a. Further, the saturated liquid of the refrigerant decreases from the hollow portion of the cold plate 10 as the refrigerant evaporates. The amount of the decrease is the level of the saturated liquid (as the refrigerant vapor escapes from the gas discharge port 13a). Height), that is, the saturated liquid of the refrigerant is naturally supplied from the gas-liquid separator 50 and replenished by the potential energy. That is, the supply of the saturated liquid of the refrigerant and the discharge of the generated steam are smoothly performed by a so-called thermosiphon, the pressure in the circulation system constituted by the gas-liquid separator 50 and the cold plate 10 is made constant, and the refrigerant The temperature can be kept from fluctuating.

  On the other hand, the saturated vapor of the refrigerant accumulated in the upper portion of the gas-liquid separator 50 is sent to the accumulator 60 via the pressure adjustment valve 80. In principle, the refrigerant vapor sent from the gas-liquid separator 50 to the accumulator 60 should be a gas phase single phase, but the saturated vapor of the refrigerant accumulated in the gas-liquid separator 50 contains the expansion valve 40. The refrigerant vapor discharged from the outlet header 13 of the cold plate 10 is included in addition to the vapor separated from the mixed phase of the refrigerant sent from. At the moment when the high-temperature glass substrate W immediately after the heat treatment is placed on the cold plate 10, the refrigerant boils violently in the hollow portion, and the refrigerant mist (microfluid) is contained in the refrigerant vapor discharged from the outlet header 13. Drops) may be mixed. As described above, if the refrigerant vapor containing the liquid phase is sucked into the compressor 20, it causes a failure. Therefore, the accumulator 60 separates the liquid phase from the supplied refrigerant vapor so that only the vapor phase is obtained. It is sent to the evaporator 70.

  The evaporator 70 sends the refrigerant sent from the accumulator 60 to the compressor 20 in a completely gas phase state. This evaporator 70 is also for removing the liquid phase from the vapor of the refrigerant fed to the compressor 20. The refrigerant immediately after being sent out from the gas-liquid separator 50 is a saturated vapor shown in the state F, but is slightly overheated in the process of passing through the accumulator 60 and the evaporator 70 to be completely in the gas phase, and in the state A. It returns to the superheated steam of the refrigerant shown and is sucked into the compressor 20.

  As described above, the refrigerant is circulated in the substrate cooling apparatus 1, and only the saturated liquid of the refrigerant generated in the middle of the circulation path is supplied to the cold plate 10, and the hollow portion is filled with the refrigerant saturated liquid. ing. The cycle itself from state A to state D in FIG. 4 is a refrigeration cycle that is also realized in a conventional cooling system. For example, a cooling system provided in a refrigerator, an air conditioner, or the like also executes a refrigeration cycle from state A to state D in FIG.

  However, in such a conventional cooling system, the mixed phase of the saturated liquid and the saturated vapor of the refrigerant shown in the state D is supplied as it is to the cooling section that absorbs heat. If the mixed fluid is supplied as it is, since a gas phase exists, heat transfer efficiency with high boiling heat transfer cannot be obtained sufficiently, and it is difficult to obtain good cooling efficiency. In addition, because the mixed fluid is forced to flow to the cooling section, a fluid pressure drop due to pipe resistance occurs and the saturation temperature decreases, but as a result of the case of forced convection heat transfer described above Conversely, a phenomenon occurs in which the temperature is slightly lower in the vicinity of the outlet side than in the vicinity of the fluid inlet side of the cooling unit. However, in the case of a refrigerator, an air conditioner, etc., it is sufficient to sequentially cool the air circulating in the cabinet or the room, so even if the cooling efficiency is somewhat poor or the temperature distribution of the cooling part is slightly uneven. There is no particular problem.

  When the substrate for precision electronic devices is cooled as in the substrate cooling apparatus 1 according to the present invention, high cooling efficiency and uniform temperature distribution are required. Phase is changed because only the liquid phase (that is, the saturated liquid of the refrigerant in the state E) is separated from the mixed fluid of the refrigerant, and the cold liquid of the cold plate 10 is filled with the saturated liquid of the refrigerant. It is possible to fully utilize the heat transfer efficiency of the boiling heat transfer accompanied with, and to obtain good cooling efficiency. Further, since the forced flow of the refrigerant saturated liquid does not exist in the hollow portion of the cold plate 10, there is no pressure drop of the refrigerant saturated liquid due to the pipe resistance, and the refrigerant extends from the vicinity of the inlet header 12 to the vicinity of the outlet header 13. The temperature of the saturated liquid is constant, and as a result, the temperature of the cold plate 10 can be made uniform and the in-plane temperature distribution uniformity of the glass substrate W being cooled can be maintained.

  In order to stably maintain such temperature uniformity, the vapor of the refrigerant generated from the saturated liquid due to the thermal load is discharged from the communication flow path 14 via the discharge side flow path 13b and the gas discharge port 13a. It is also necessary to suppress the decrease in the saturation temperature of the refrigerant by reducing the gas-phase discharge resistance (pressure loss) as much as possible. The pressure loss Δp when the refrigerant vapor having the flow velocity u flows through the pipe having the length (flow path length) l and the inner diameter d is expressed by the following equation (1) (Darcy-Weisbach equation).

  In Equation 1, C is a resistance coefficient, which is a value defined by the relative roughness of the inner wall surface of the pipe and the Reynolds number. As is clear from Equation 1, the pressure loss increases as the length of the pipe increases and the inner diameter decreases. The flow velocity u of the refrigerant vapor is expressed by Equation 2.

  Q is the flow rate of the refrigerant vapor. In the substrate cooling apparatus 1 of the present embodiment, only the saturated liquid (liquid phase) of the refrigerant is supplied to the hollow portion of the cold plate 10, so that the flow rate of the refrigerant vapor is equal to the evaporation amount of the refrigerant due to the heat load. From the equations 1 and 2, the pressure loss Δp is expressed as the following equation 3.

  On the other hand, the variation in the temperature distribution allowed in the substrate cooling apparatus 1 for cooling the glass substrate W is determined by the manufacturing standard. If the glass substrate W is a glass substrate for a liquid crystal display device, it is within a range of ± 1 ° C. from the set temperature. It is. Therefore, it is necessary to suppress the pressure loss so that the fluctuation of the saturation temperature of the refrigerant becomes ± 1 ° C. or less due to the pressure loss when the refrigerant vapor generated from the saturated liquid by the heat load flows through the communication channel 14. For example, when the set temperature of the cooling process is 23 ° C., it is necessary to suppress the pressure loss so that the fluctuation of the saturation temperature of the refrigerant falls within the range of 22 ° C. to 24 ° C. The refrigerant used in this embodiment is Freon (R134a), the saturation pressure for the saturation temperature of 24 ° C. is 0.553 MPa, and the saturation pressure for the saturation temperature of 22 ° C. is 0.514 MPa. Therefore, the pressure loss Δp needs to be 0.553 MPa−0.514 MPa = 0.039 MPa or less (preferably one tenth of 0.0039 MPa or less). Further, if an alternative Freon (R410A) different from the above is used, the saturation pressure for the saturation temperature of 24 ° C. is 1.55 MPa, and the saturation pressure for the saturation temperature of 22 ° C. is 1.46 MPa. Therefore, the pressure loss Δp needs to be 1.55 MPa-1.46 MPa = 0.09 MPa or less (preferably one tenth of 0.009 MPa or less).

  As a result of detailed experiments, the present inventors have found that when the length of the communication channel 14 is l1 = 255 mm and the inner diameter d1 = φ8 mm, the change in the saturation temperature of the refrigerant is ± 1 ° C. or less. Therefore, if the communication flow path 14 is designed so as to have a pressure loss equivalent to that under this condition, more specifically, the length l2 and the inner diameter d2 of the communication flow path 14 satisfy the following relationship: By doing so, the change in the saturation temperature of the refrigerant due to the pressure loss when the vapor of the refrigerant generated from the saturated liquid flows through the communication channel 14 can be made ± 1 ° C. or less. In Equation 4, Q1 and Q2 are the flow rate of the refrigerant vapor (that is, the amount of refrigerant evaporated) in the communication channel 14 to be designed and tested, respectively, and can be easily calculated from the heat capacity of the glass substrate W. it can. In practice, the pressure loss in the discharge side flow path 13b also affects the fluctuation of the saturation temperature of the refrigerant. However, the inner diameter of the discharge side flow path 13b is considerably larger than the communication flow path 14 (φ36 mm). Since the influence is sufficiently small compared to the communication channel 14, it is excluded from consideration here.

  From only the relationship of Equation 4, it can be derived that the pressure loss can be maintained at the same level by increasing both the length and the inner diameter as compared with the communication channel 14 in the experiment. However, in the cold plate 10, the plurality of communication channels 14 are arranged along the X-axis direction at a predetermined arrangement pitch. If the arrangement pitch is too large, a striped temperature distribution is generated. The arrangement pitch is about 20 mm regardless of the size of the cold plate 10. Therefore, the upper limit of the inner diameter of the communication channel 14 is regulated by the arrangement pitch, and the upper limit of the inner diameter d2 is about φ14 mm. When the upper limit of the inner diameter d2 of the communication flow path 14 is defined, the upper limit of the length 12 of the communication flow path 14 is also determined from the relationship of Equation 4. In the present embodiment, the upper limit value of the length l2 of the communication flow path 14 obtained in this way is set as the “reference length”, and is about 600 mm under the above conditions. Since this “reference length” satisfies the relationship of Equation 4, the change in the saturation temperature of the refrigerant becomes ± 1 ° C. or less due to the pressure loss when the refrigerant vapor generated from the saturated liquid flows through the communication channel 14 due to the thermal load. This is the length of the communication channel 14. Conversely, if the length of the communication channel 14 exceeds the reference length of 600 mm, the saturation temperature of the refrigerant is greatly reduced due to pressure loss, and the variation in the in-plane temperature distribution during the cooling process exceeds the allowable limit. There is a risk.

  By the way, glass substrates for liquid crystal display devices and the like are steadily increasing in size, and in the eighth generation (G8), the size is increased to 2400 mm × 2600 mm. When such a large glass substrate W is cooled by the substrate cooling apparatus 1, the cold plate is divided into a plurality of pieces as shown in FIG. That is, a plurality of unit cold plates 10a are juxtaposed to form a single large cold plate. 6 is a plan view of the cold plate of FIG. As shown in FIGS. 5 and 6, in the substrate cooling apparatus 1 for processing the 8th generation glass substrate W, the four unit cold plates 10a are arranged in the Y-axis direction (second direction) orthogonal to the X-axis direction. A large-sized cold plate is formed side by side. Each unit cold plate 10 a includes a liquid supply port 12 a, a gas discharge port 13 a, a supply side flow channel 12 b, a discharge side flow channel 13 b, and a plurality of communication flow channels 14, similar to the cold plate 10 described above. The plurality of communication channels 14 are arranged along the X-axis direction between the supply-side channel 12b and the discharge-side channel 13b. The length of each communication channel 14 is the above-mentioned reference length (600 mm), and the inner diameter is φ14 mm. The X-axis direction length of the unit cold plate 10a is 2600 mm.

  In this way, the unit cold plate 10a individually including the unit supply / discharge system including the liquid supply port 12a, the gas discharge port 13a, the supply side flow channel 12b, the discharge side flow channel 13b, and the plurality of communication channels 14 having a reference length. By arranging four in parallel, even a large eighth generation glass substrate W can be handled. Since the length of the communication channel 14 in each unit cold plate 10a is a reference length that satisfies the relationship of Equation 4, variations in the in-plane temperature distribution when the large glass substrate W is cooled are suppressed. Further, even when a glass substrate W that is larger than the eighth generation is to be processed in the future, by increasing the number of unit cold plates 10a having the communication channel 14 having a reference length in parallel. It is possible. In addition, about the X-axis direction length of the unit cold plate 10a, it can change easily only by increasing / decreasing the number of the connection flow paths 14 installed.

  In the substrate cooling apparatus 1 of the present embodiment, a structure in which a plurality of communication channels 14 are arranged in a row from the supply-side channel 12b extending along the X-axis direction to the discharge-side channel 13b extending in parallel therewith. Thus, the supply / discharge system of the cooling mechanism is configured, so that the saturated liquid of the refrigerant can be filled quietly so that the inside of the cold plate 10 is uniform and does not cause pressure loss. For this reason, the above-mentioned effect that the glass substrate W can be cooled with good cooling efficiency and the in-plane temperature distribution uniformity of the glass substrate W being cooled can be maintained reliably.

  Further, in the substrate cooling apparatus 1 of the present embodiment, the refrigerant saturated liquid is supplied from the lowest height position of the hollow portion of the cold plate 10 and the refrigerant vapor is discharged from the highest height position. The generated refrigerant vapor is smoothly discharged from above, and the inside of the hollow portion can be constantly maintained in a state where the saturated liquid of the refrigerant is filled gently. For this reason, said effect can be acquired reliably.

  Further, the substrate cooling apparatus 1 includes a temperature controller 93 that controls the pressure regulating valve 80 and the bypass valve 85 based on the temperature of the cold plate 10 measured by the temperature sensor 19. The temperature controller 93 monitors the plate temperature of the cold plate 10 and controls the pressure adjustment valve 80 so that the plate temperature always becomes the cooling target temperature of the glass substrate W, thereby adjusting the vapor pressure in the gas-liquid separator 50. It is adjusted. Specifically, when a high temperature glass substrate W is placed on the cold plate 10 and a thermal load is applied, the pressure regulating valve 80 is opened, and the temperature of the glass substrate W is lowered to reduce the thermal load. When this happens, the pressure regulating valve 80 is throttled.

  When the high-temperature glass substrate W is placed on the cold plate 10, the saturated liquid of the refrigerant filled in the hollow portion suddenly boils and evaporates, and a large amount of refrigerant vapor is discharged from the outlet header 13. It flows into the separator 50. Then, the vapor pressure in the gas-liquid separator 50 increases, the temperature of the refrigerant saturated liquid also increases, and the temperature of the cold plate 10 may become higher than the target temperature. For this reason, the temperature controller 93 increases the degree of opening of the pressure regulating valve 80 to prevent the vapor pressure in the gas-liquid separator 50 from increasing, thereby preventing the temperature of the refrigerant saturated liquid from rising.

  On the other hand, when the thermal load on the cold plate 10 has been reduced, the amount of refrigerant vapor generated also decreases. Therefore, if the pressure regulating valve 80 is kept largely open, the vapor pressure in the gas-liquid separator 50 is increased. There is a possibility that the temperature of the refrigerant saturated liquid is lowered too much and the temperature of the cold plate 10 becomes lower than the target temperature. For this reason, the temperature controller 93 reduces the opening degree of the pressure regulating valve 80 to prevent the vapor pressure in the gas-liquid separator 50 from excessively decreasing, and prevents the temperature of the refrigerant saturated liquid from decreasing.

  Further, the temperature controller 93 opens the bypass valve 85 and causes the supercooled liquid of the refrigerant to flow directly to the evaporator 70 when the plate temperature of the cold plate 10 falls below a predetermined setting range. This operation is an emergency measure for stopping the supply of the refrigerant to the cold plate 10 when the plate temperature is abnormally lowered to prevent the condensation on the cold plate 10 from the atmosphere. Specifically, the plate temperature should not be less than 10 ° C. in an atmosphere of 23 ° C. and 40% relative humidity.

  In addition, the substrate cooling apparatus 1 includes a level controller 96 that controls the operation of the compressor 20 based on the liquid level in the gas-liquid separator 50 detected by the level sensor 55. Based on the detection result of the level sensor 55, the level controller 96 controls the operation of the compressor 20 so that the liquid level of the saturated liquid of the refrigerant stored in the gas-liquid separator 50 becomes constant. That is, when the thermal load on the cold plate 10 is large and the consumption amount of the refrigerant saturated liquid is large, the liquid level of the refrigerant saturated liquid stored in the gas-liquid separator 50 is lowered. In such a case, the level controller 96 increases the operation amount of the compressor 20 and increases the amount of refrigerant saturated liquid fed to the gas-liquid separator 50. On the contrary, when the thermal load on the cold plate 10 has been reduced, the level level of the refrigerant saturated liquid stored in the gas-liquid separator 50 increases, so that the level controller 96 operates the compressor 20. The amount is reduced, and the amount of refrigerant saturated liquid fed to the gas-liquid separator 50 is reduced. In this way, the liquid level of the saturated liquid refrigerant stored in the gas-liquid separator 50 is constantly constant. The basic method of increasing / decreasing the operation amount is to control the rotation speed of the compressor 20 by an inverter or to change the number of compressors 20 to be operated when using a plurality of compressors 20.

  Further, the control unit 90 of the substrate cooling apparatus 1 controls the expansion valve 40 based on the operating state of the compressor 20. The control unit 90 switches the expansion valve 40 to two stages of either a large flow rate or a small flow rate based on the operation amount of the compressor 20. Specifically, the control unit 90 sets the expansion valve 40 to a large flow rate when the operation amount of the compressor 20 is greater than a predetermined reference value, and sets the expansion valve 40 to a small flow rate when the operation amount is less than the reference value. When the operation amount of the compressor 20 is equal to the reference value, the expansion valve 40 may be set to either a large flow rate or a small flow rate. If it does in this way, according to the operating state of the compressor 20, the refrigerant | coolant amount which expands through the expansion valve 40 can be adjusted.

  While the embodiments of the present invention have been described above, the present invention can be modified in various ways other than those described above without departing from the spirit of the present invention. For example, the form of the cold plate 10 is not limited to the form shown in FIGS. 2 and 3, a hollow portion is provided inside the plate, and the refrigerant is supplied from the liquid supply port provided at the lowest height position of the hollow portion. As long as the saturated liquid is supplied, the vapor of the refrigerant may be discharged from the gas discharge port provided at the highest height position. Further, in the cold plate 10, the communication channel 14 may be provided with a slight inclination so that the vapor of the refrigerant is more smoothly discharged from the gas discharge port 13a.

  Further, when processing a large glass substrate W, the configuration shown in FIG. 7 may be used instead of the configuration shown in FIGS. In the configuration of FIG. 7, the cold plate is not divided, but a single large cold plate 10b is provided with a liquid supply port 12a, a gas discharge port 13a, a supply side flow channel 12b, a discharge side flow channel 13b, and a reference length. A plurality of unit supply / discharge systems including a plurality of communication channels 14 are arranged in parallel along the Y-axis direction. That is, a single large cold plate 10b is provided with a cooling mechanism similar to that shown in FIGS. Even in this case, it is possible to deal with a large eighth-generation glass substrate W. Moreover, since the length of the communication channel 14 is a reference length that satisfies the relationship of Equation 4, variations in temperature distribution when the large glass substrate W is cooled are suppressed. Of course, the configuration shown in FIGS. 5 and 6 can easily cope with an increase in the size of the glass substrate W only by increasing the number of unit cold plates 10a arranged in parallel.

  Further, the cooling system of the substrate cooling apparatus 1 according to the present invention may include a plurality of compressors 20. In this case, the level controller 96 is based on the detection result of the level sensor 55, and the number of compressors 20 that operate so that the liquid level of the saturated liquid of the refrigerant stored in the gas-liquid separator 50 is constant. Adjust. Further, the control unit 90 switches the expansion valve 40 to two stages of either a large flow rate or a small flow rate based on the number of operating compressors 20.

  Further, the substrate to be cooled by the substrate cooling apparatus 1 according to the present invention is not limited to the glass substrate W, and may be a semiconductor wafer.

  In addition, the cooling system according to the present invention may cool the structure instead of the substrate. In other words, the plate body 11 may be mounted on a structure, for example, a mold to cool the mold that is the structure.

It is a figure which shows the structure of the cooling system of the substrate cooling device which concerns on this invention. It is a perspective view of a cold plate. It is the VV sectional view taken on the line of FIG. 2 which shows the internal structure of a cold plate. It is a Mollier diagram. It is a perspective view of a division | segmentation cold plate. It is a top view of the division | segmentation cold plate of FIG. It is a top view of a large sized cold plate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate cooling device 10 Cold plate 10a Unit cold plate 10b Large cold plate 11 Plate main-body part 12 Inlet header 12a Liquid supply port 12b Supply side flow path 13 Outlet header 13a Gas discharge port 13b Discharge side flow path 14 Connection flow path 19 Temperature sensor DESCRIPTION OF SYMBOLS 20 Compressor 30 Capacitor 40 Expansion valve 50 Gas-liquid separator 55 Level sensor 60 Accumulator 70 Evaporator 80 Pressure adjustment valve 85 Bypass valve 90 Control part 93 Temperature controller 96 Level controller

Claims (13)

A substrate cooling device that cools a substrate placed on a cooling plate to a predetermined temperature,
A substrate cooling apparatus, wherein a hollow portion is provided inside the cooling plate, and the hollow portion is filled with a saturated liquid of a refrigerant. The substrate cooling apparatus according to claim 1,
The cooling plate is
A liquid supply port that is provided at the lowest height position of the hollow portion and supplies a saturated liquid of a refrigerant to the hollow portion;
A gas discharge port for discharging a refrigerant vapor generated from a saturated liquid of a refrigerant boiled in the hollow part, provided at the highest position of the hollow part;
A substrate cooling apparatus comprising: The substrate cooling apparatus according to claim 1,
The cooling plate is
A liquid supply port for supplying a saturated liquid coolant to the hollow portion;
A gas outlet for discharging the vapor of the refrigerant generated from the saturated liquid of the refrigerant boiling in the hollow portion;
With
The hollow part is
A supply-side flow path communicating with the liquid supply port and extending along a first direction;
A discharge-side flow path that communicates with the gas discharge port and is provided in parallel with the supply-side flow path;
A plurality of connecting flow paths arranged in line between the supply side flow path and the discharge side flow path along the first direction, and connecting the supply side flow path and the discharge side flow path;
A substrate cooling apparatus comprising: The substrate cooling apparatus according to claim 3, wherein
The substrate cooling apparatus according to claim 1, wherein the first direction is a horizontal direction, and the discharge-side flow path is provided at a position higher than the supply-side flow path. In the substrate cooling device according to claim 3 or 4,
The length of the communication channel is a reference length in which a variation in the saturation temperature of the refrigerant due to a pressure loss when the generated refrigerant vapor flows is a predetermined length or less. The substrate cooling apparatus according to claim 5, wherein
The substrate cooling apparatus according to claim 1, wherein the reference length is a length at which a variation in the saturation temperature is ± 1 ° C. or less. The substrate cooling apparatus according to claim 5 or 6,
The cooling plate is
A unit supply / discharge system having the liquid supply port, the gas discharge port, the supply side flow channel, the discharge side flow channel, and a plurality of communication flow channels of the reference length is secondly orthogonal to the first direction. A substrate cooling apparatus comprising a plurality of the plurality of semiconductor cooling apparatuses arranged along the direction of the substrate. The substrate cooling apparatus according to claim 5 or 6,
The cooling plate having the liquid supply port, the gas discharge port, the supply-side flow channel, the discharge-side flow channel, and the plurality of communication channels of the reference length is arranged in a second direction orthogonal to the first direction. A substrate cooling apparatus comprising a plurality of the substrate cooling apparatuses arranged in parallel. The substrate cooling apparatus according to any one of claims 2 to 8,
A compressor for compressing the vapor of the refrigerant;
A condenser for condensing the superheated steam of the refrigerant generated by the compressor;
An expansion valve for expanding the saturated or supercooled liquid of the refrigerant generated by the condenser;
A gas-liquid separator that separates a mixed phase of a saturated liquid and a saturated vapor of refrigerant generated by the expansion valve into a liquid phase and a gas phase;
Further comprising
The substrate cooling apparatus, wherein only the saturated liquid of the refrigerant separated by the gas-liquid separator is supplied from the liquid supply port to the hollow portion. The substrate cooling apparatus according to claim 9, wherein
A substrate cooling apparatus, wherein a vapor of a refrigerant generated from a saturated liquid of a refrigerant boiling in the hollow portion is returned to the gas-liquid separator from the gas discharge port. The substrate cooling apparatus according to claim 9 or 10,
A temperature measuring unit for measuring the temperature of the cooling plate;
A pressure regulating valve interposed in a pipe for supplying refrigerant vapor from the gas-liquid separator to the compressor;
Based on the temperature of the cooling plate measured by the temperature measuring unit, the pressure regulating valve is controlled to adjust the vapor pressure in the gas-liquid separator so that the temperature of the cooling plate becomes the predetermined temperature. Temperature control means;
A substrate cooling apparatus further comprising: The substrate cooling apparatus according to any one of claims 9 to 11,
A liquid level detecting unit for detecting a liquid level of a saturated liquid of a refrigerant stored in the gas-liquid separator;
Level control means for controlling the operation of the compressor based on the detection result of the liquid level detector so that the liquid level of the saturated liquid of the refrigerant stored in the gas-liquid separator is constant. ,
A substrate cooling apparatus further comprising: A structure cooling device for cooling a structure to which a cooling plate is mounted to a predetermined temperature,
A cooling device for a structure, wherein a hollow portion is provided inside the cooling plate, and the hollow portion is filled with a saturated liquid of a refrigerant.

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