Constant temperature liquid supply device

Abstract

To adjust liquid to a prescribed temperature by a small-sized configuration which is simple and at operation cost.SOLUTION: A constant temperature liquid supply device for supplying liquid with an adjusted temperature to a processing device provided with a processing unit having a spindle attached with a processing tool and a motor for rotating the spindle includes a tank for storing the liquid, a thermometer for measuring the temperature of the liquid stored in the tank, and a compressed gas supply pipe, the one end of which is connected to a compressed gas source for storing a compressed gas, the other end of which reaches the tank to supply the compressed gas from the compressed gas source to the tank, and cools the liquid stored in the tank with bubbles of the compressed gas, and supplies the cooled liquid to the processing device.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a constant temperature liquid supplying device that supplies liquid at a predetermined temperature to a processing device that processes workpieces such as semiconductor wafers. [Background technology]

[0002] In the manufacturing process of device chips used in electronic devices such as mobile phones and personal computers, first, a plurality of intersecting planned dividing lines (streets) are set on the surface of a wafer made of a material such as a semiconductor. Then, devices such as ICs (Integrated Circuits) and LSIs (Large Scale Integration) are formed in each area defined by the planned dividing lines. The wafer is then divided along the planned dividing lines to form individual device chips.

[0003] A cutting device is used to divide the wafer. The cutting device has a spindle and an annular cutting blade attached to the tip of the spindle. When cutting the wafer, the cutting blade is rotated by rotating the spindle and lowered to a predetermined height. The wafer and the cutting blade are then moved relative to each other, and the cutting blade cuts into the wafer along the intended division line.

[0004] Furthermore, to ultimately obtain thin device chips, the wafer before division is thinned by grinding from the backside using a grinding device. The grinding device has a spindle and an annular grinding wheel attached to the lower end of the spindle. The grinding wheel has grinding stones arranged in an annular pattern. The grinding wheel is rotated by rotating the spindle, and the grinding wheel is lowered toward the backside of the workpiece. When the grinding stones come into contact with the workpiece, the workpiece is ground.

[0005] When a workpiece is processed using these processing devices, the temperatures of the spindle, cutting blade, grinding wheel, and other processing tools that make up the processing unit, and the workpiece, rise due to the effects of friction, causing thermal expansion in the spindle, processing tools, workpiece, etc., which changes the processing results. Therefore, in order to process workpieces with little variation in the processing device, it is important to control the temperatures of the processing unit and the workpiece with high precision to prevent the effects of thermal expansion.

[0006] Therefore, a liquid such as cooling water adjusted to a predetermined temperature is circulated and supplied to the processing unit, and the liquid adjusted to a predetermined temperature is supplied to the processing tool and the workpiece. A constant temperature liquid supply device for supplying liquid at a predetermined temperature is connected to and used in the processing device (see, for example, Patent Documents 1 to 3). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-127343 [Patent Document 2] Japanese Patent Application Publication No. 2017-215063 [Patent Document 3] Japanese Patent Application Publication No. 2017-156017 Summary of the Invention [Problem to be solved by the invention]

[0008] A constant temperature liquid supply device is equipped with a cooling means or temperature adjustment means for adjusting the temperature of the liquid, but since these are mainly driven by electricity, the operation of a constant temperature liquid supply device incurs a non-negligible cost.

[0009] Furthermore, these constant temperature liquid supply devices often have the ability to supply liquid such as water at a predetermined temperature to multiple processing devices simultaneously, and are equipped with cooling means or the like with the output required to achieve this. Therefore, for example, even when supplying constant temperature liquid to one processing device, a high-output cooling means must be operated, which results in a problem of relatively high operating costs.

[0010] The present invention has been made in consideration of such problems, and its object is to provide a constant temperature liquid supply device that can adjust liquid to a predetermined temperature with low operating costs and a simple, compact configuration. [Means for solving the problem]

[0011] According to one aspect of the present invention, there is provided a constant temperature liquid supply device for supplying a temperature-controlled liquid to a processing device having a processing unit having a spindle to which a processing tool is attached and a motor for rotating the spindle, the constant temperature liquid supply device comprising: a tank for storing the liquid; a thermometer for measuring the temperature of the liquid stored in the tank; and a compressed gas supply pipe having one end connected to a compressed gas source for storing compressed gas and the other end reaching the tank, the compressed gas being supplied from the compressed gas source to the tank; The height of the tank is greater than the square root of the cross-sectional area of ​​a cross section parallel to the bottom surface of the tank; A constant temperature liquid supplying apparatus is provided which cools the liquid contained in the tank by bubbles of the compressed gas and supplies the cooled liquid to the processing device. According to another aspect of the present invention, there is provided a constant temperature liquid supply device that supplies temperature-controlled liquid to a processing device equipped with a processing unit having a spindle to which a processing tool is attached and a motor that rotates the spindle, the constant temperature liquid supply device comprising: a rectangular tank that contains the liquid; a thermometer that measures the temperature of the liquid contained in the tank; and a compressed gas supply pipe that has one end connected to a compressed gas source that stores compressed gas and the other end reaching the tank and that supplies the compressed gas from the compressed gas source to the tank, wherein the height of the tank is greater than the length of each side of the bottom of the tank, and the liquid contained in the tank is cooled by bubbles of the compressed gas and the cooled liquid is supplied to the processing device.

[0012] Preferably, the apparatus further comprises a filter connected to the other end of the compressed gas supply pipe for releasing the supplied compressed gas into the liquid as bubbles.

[0013] More preferably, the liquid supplied to the processing device cools the processing unit, then returns to the tank, is cooled by the air bubbles, and is supplied to the processing device again.

[0014] Preferably, the liquid supplied to the processing device is supplied to the processing tool and used as a processing liquid.

[0015] Preferably, the liquid is pure water and the compressed gas is compressed air. [Effects of the Invention]

[0016] A constant temperature liquid supply device according to one aspect of the present invention includes a tank for storing a liquid and a compressed gas supply pipe connected at one end to the tank. When compressed gas is supplied from the compressed gas supply pipe to the liquid stored in the tank, bubbles of the compressed gas are generated in the liquid. As the compressed gas expands, the temperature of the bubbles drops, and as the bubbles rise in the tank, the liquid in contact with the bubbles is cooled.

[0017] In other words, because the liquid can be cooled simply by supplying compressed gas to the liquid stored in the tank, a large-scale cooling means is not required, and the constant temperature liquid supply device can be made smaller.Furthermore, the power and energy required to operate the constant temperature liquid supply device are extremely low, which reduces operating costs.

[0018] Thus, according to one aspect of the present invention, a constant temperature liquid supply device is provided that can regulate liquid to a predetermined temperature with a simple, compact configuration and low operating costs. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 2 is a perspective view schematically showing a processing device and a constant-temperature liquid supply device. [Figure 2] FIG. 2 is a perspective view schematically showing how a workpiece is processed by the processing device. [Figure 3] FIG. 2 is a cross-sectional view schematically illustrating an example of a tank. [Figure 4] FIG. 10 is a cross-sectional view schematically showing another example of the tank. DETAILED DESCRIPTION OF THE INVENTION

[0020] An embodiment of the present invention will be described with reference to the accompanying drawings. A constant temperature liquid supply device according to this embodiment is used by being connected to, for example, various processing devices that process workpieces. The processing devices include, for example, a cutting device that cuts thin plate-like workpieces such as semiconductor wafers, a grinding device that grinds them, a polishing device that polishes them, or a laser processing device that laser processes them.

[0021] The cutting device has an annular cutting blade as a processing tool, rotates a spindle with the cutting blade attached to its tip, and cuts the workpiece by bringing the rotating cutting blade into contact with the workpiece.The grinding device has a grinding wheel as a processing tool, with multiple grinding stones arranged in an annular shape, rotates a spindle with the grinding wheel attached to its lower end, and grinds the workpiece by bringing the grinding stones, which move on an annular track, into contact with the workpiece.

[0022] The polishing apparatus has a disk-shaped polishing pad as a processing tool, and polishes the workpiece by rotating a spindle with the polishing pad attached to its lower end and bringing the rotating polishing pad into contact with the workpiece. Hereinafter, this embodiment will be described using an example in which the processing apparatus to which the constant temperature liquid supply device according to this embodiment is connected is a cutting apparatus, but the constant temperature liquid supply device is not limited to this and may be connected to other processing apparatuses or to apparatuses other than processing apparatuses.

[0023] The workpiece processed by the processing device is, for example, a substantially disk-shaped wafer made of Si (silicon), SiC (silicon carbide), GaN (gallium nitride), GaAs (gallium arsenide), or other semiconductor material. Alternatively, the workpiece is a plate-shaped substrate made of a material such as sapphire, quartz, glass, or ceramic. Examples of such glass include alkali glass, non-alkali glass, soda-lime glass, lead glass, borosilicate glass, and quartz glass. However, there are no particular limitations on the workpiece.

[0024] 2 includes a perspective view that schematically shows a disk-shaped semiconductor wafer, which is an example of the workpiece 1. For example, a plurality of devices 5, such as ICs and LSIs, are formed on the surface 1a of the workpiece 1. Dividing lines 3 are set between the devices 5 on the workpiece 1. Then, by cutting the workpiece 1 along the dividing lines 3 with a cutting device to form dividing grooves 3a and divide the workpiece 1, individual device chips can be formed.

[0025] Before being carried into the cutting device, the workpiece 1 is integrated with the dicing tape 9 and the ring frame 7 to form a frame unit 11. The dicing tape 9 is attached to the ring frame 7 so as to close the opening of the ring frame 7, and the back surface 1b of the workpiece 1 is attached to the dicing tape 9 exposed in the opening.

[0026] When the frame unit 11 is formed, the workpiece 1 can be handled via the ring frame 7 and dicing tape 9, making it easy to handle the workpiece 1. Furthermore, the device chips formed by dividing the workpiece 1 are fixed directly to the dicing tape 9, making it easy to handle the device chips. After dividing the workpiece 1, expanding the dicing tape 9 radially outward inside the opening of the ring frame 7 creates gaps between the individual device chips, making it easy to pick up the device chips.

[0027] Next, a cutting device will be described as an example of a processing device to which a constant temperature liquid supply device can be connected. FIG. 1 is a perspective view showing a schematic diagram of a cutting device 2. The cutting device 2 has a base 4 that supports each of its components. A rectangular opening 4a is formed in the top surface of the base 4, and a gate-shaped support structure 12 that supports a cutting unit 16 that cuts the workpiece 1 is disposed so as to straddle the opening 4a. A cutting unit movement mechanism 14 that moves the cutting unit 16 in the indexing feed direction and vertical direction is provided on the upper front surface of the support structure 12.

[0028] The opening 4a of the base 4 is formed in a rectangular shape that is perpendicular to the indexing feed direction and is long in the processing feed direction that is perpendicular to the vertical direction. A moving table (not shown), a moving mechanism (not shown) that moves the moving table in the processing feed direction, and dustproof and drip-proof covers 6 and 8 that cover the moving mechanism are provided within this opening 4a.

[0029] A chuck table 10 for suction-holding the workpiece 1 is disposed on the moving table. A porous member is disposed on the upper surface of the chuck table 10, and one end of the porous member is connected to a suction path (not shown) connected to a suction source. The upper surface of the porous member serves as the holding surface 10a. The chuck table 19 further includes clamps 10b on the radial outside of the holding surface 10a for fixing the ring frame 7 constituting the frame unit 11.

[0030] When the frame unit 11 is placed on the holding surface 10a of the chuck table 10, the ring frame 7 is fixed with the clamp 10b, and the suction source is activated, negative pressure acts on the workpiece 1, and the workpiece 1 is held by suction to the chuck table 10 via the dicing tape 9.

[0031] The cutting unit (processing unit) 16 includes a spindle (not shown) along the indexing feed direction, a spindle housing 18 that rotatably supports the spindle, and an annular cutting blade (processing tool) 22 attached to one end of the spindle. The cutting blade 22 is covered by a blade cover 20. A rotational drive source (not shown) such as a motor is connected to the other end of the spindle, and the cutting blade 22 rotates by rotational force transmitted from the rotational drive source via the spindle.

[0032] 2 is a perspective view showing a schematic view of cutting the workpiece 1 with the cutting unit 16. When cutting the workpiece 1 with the cutting blade 22, the cutting blade 22 is positioned on an extension of the planned dividing line 3 of the workpiece 1, the rotary drive source is activated to start the rotation of the cutting blade 22, and the cutting blade 22 is lowered to cut into the surface of the dicing tape 9. Thereafter, the chuck table 10 is moved to move the frame unit 11 in the processing feed direction, and the cutting blade 22 is caused to cut into the workpiece 1, forming the dividing grooves 3a.

[0033] Thereafter, the cutting blade 22 is raised and moved to an extension of the other planned dividing lines 3, and the cutting blade 22 is caused to cut into the other planned dividing lines 3 in the same manner. After the workpiece 1 has been cut along all of the planned dividing lines 3 aligned in the same direction, the chuck table 10 is rotated to align the planned dividing lines 3 aligned in the other directions with the processing feed direction of the cutting device 2. Then, when the workpiece 1 is cut in the same manner, the workpiece 1 is divided into individual device chips.

[0034] When the cutting blade 22 cuts into the workpiece 1, cutting chips are generated from the workpiece 1 and the grinding wheel portion of the cutting blade 22. Frictional heat is also generated between the workpiece 1 and the cutting blade 22. Therefore, the cutting unit 16 is provided with a pair of cutting water supply nozzles 28 that supply cutting water such as pure water to the workpiece 1 and the cutting blade 22 while the workpiece 1 is being cut. The pair of cutting water supply nozzles 28 extend on the sides of the cutting blade 22 so as to sandwich the cutting blade 22 on both sides.

[0035] When cutting water is supplied from the cutting water supply nozzle 28 to the workpiece 1 and the cutting blade 22 while the workpiece 1 is being cut with the cutting blade 22, the cutting water removes the chips and frictional heat generated during cutting. Therefore, the workpiece 1 can be cut stably.

[0036] When the rotary drive source that rotates the cutting blade 22 is operated, frictional heat is generated due to the rotation of the spindle, etc. If the temperature of the spindle, etc. rises and the spindle, etc., expands thermally, the position of the cutting blade 22 changes, making it impossible to properly cut the workpiece 1. Therefore, while the rotary drive source is operating, it must be cooled and kept at a constant temperature.

[0037] Therefore, a constant temperature liquid supply device 24 (see FIG. 1) is connected to the cutting device (processing device) 2, and liquid at a constant temperature is sent from the constant temperature liquid supply device 24 to the cutting unit 16. Then, the liquid sent to the cutting device (processing device) 2 and whose temperature has increased is returned to the constant temperature liquid supply device 24, cooled to a predetermined temperature, and sent again to the cutting device (processing device) 2. In other words, the cutting unit 16 is cooled by the circulating liquid.

[0038] Next, the constant temperature liquid supply device 24 according to this embodiment will be described. Figure 3 is a cross-sectional view showing the components of the constant temperature liquid supply device 24. The constant temperature liquid supply device 24 includes a tank 30 that contains a liquid 32, a thermometer 50 that measures the temperature of the liquid 32 contained in the tank 30, and compressed gas supply pipes 36 and 40 that are connected to the tank 30.

[0039] One end of the compressed gas supply pipes 36, 40 is connected to a compressed gas source 34 that stores compressed gas, and the other end reaches the tank 30. A regulator 38 is provided on the compressed gas supply pipes 36, 40. The regulator 38 can switch between supplying and stopping the compressed gas supplied from the compressed gas source 34 to the tank 30, and can adjust the supply pressure of the compressed gas.

[0040] The liquid 32 contained in the tank 30 is sent to the cutting device (processing device) 2, where it increases in temperature as it absorbs heat from and cools a predetermined object, and is then returned to the tank 30. In other words, the liquid 32 functions as a refrigerant. There are no particular restrictions on the type of liquid 32, and it may be selected based on the temperature at which the object to be cooled should be maintained. For example, if it is desired to maintain the temperature of the object to be cooled at approximately room temperature, pure water may be used as the liquid 32. Furthermore, if it is desired to maintain the temperature of the object to be cooled at 100°C or higher, oil may be used as the liquid 32.

[0041] Compressed gas supply pipes 36, 40, one end of which is connected to a compressed gas source 34, extend into the tank 30, and the other end is connected to a porous filter 42. The filter 42 is, for example, a hollow fiber filter made of resin. Alternatively, it may be made of a material such as ceramic. The filter 42 preferably has numerous pores with a size of about 0.1 μm. The filter 42 is disposed near the bottom of the tank 30 and is submerged in the liquid 32. A vent 30a is formed in the top of the tank 30.

[0042] When the temperature of the liquid 32 contained in the tank 30 is lowered, the regulator 38 is operated to supply compressed gas from the compressed gas source 34 to the filter 42 through the compressed gas supply pipes 36 and 40. The compressed gas supplied to the filter 42 is released into the liquid 32 through the pores of the filter 42 and becomes bubbles 44. At this time, the compressed gas is released from its high pressure state and expands rapidly, causing the temperature of the gas to drop rapidly.

[0043] Therefore, inside the tank 30, the low-temperature air bubbles 44 ejected from the filter 42 rise in the liquid 32. During this process, the liquid 32 that comes into contact with the air bubbles 44 is cooled by the air bubbles 44, lowering the temperature of the liquid 32. In other words, the constant temperature liquid supply device 24 according to this embodiment cools the liquid 32 contained in the tank 30 by the compressed gas bubbles 44 whose temperature has decreased as they expanded. The cooled liquid 32 is then supplied from the tank 30 to the cutting device (processing device) 2.

[0044] It is preferable that the compressed gas supplied from the compressed gas source 34 to the filter 42 and released into the liquid 32 be a gas that is poorly reactive with the liquid 32 and has low solubility in the liquid 32. If the compressed gas reacts with or dissolves in the liquid 32 when released into the liquid 32, it may not be possible to sufficiently cool the liquid 32, or it may significantly change the properties of the liquid 32, causing damage to the constant temperature liquid supply device 24 or the cutting device (processing device) 2.

[0045] Therefore, the compressed gas is preferably, for example, compressed air or compressed nitrogen, or may be a compressed rare gas, compressed oxygen, compressed hydrogen, etc. However, for ease of procurement and management and safety, the compressed gas is most preferably compressed air or compressed nitrogen.

[0046] When the bubbles 44 reach the upper surface of the liquid 32, the gas contained in the bubbles 44 escapes from the liquid 32, proceeds into the excess space in the tank 30, and is released to the outside of the tank 30 through the vent 30a. Therefore, the internal pressure of the tank 30 does not increase excessively. Here, the longer the time it takes for the bubbles 44 to travel through the liquid 32, the more easily heat exchange between the bubbles 44 and the liquid 32 progresses, and the liquid 32 is cooled more efficiently. Therefore, it is advisable to devise the dimensions of the tank 30 so that the time it takes for the bubbles 44 to escape from the liquid 32 is longer.

[0047] That is, it is preferable that the tank 30 is long in the vertical direction. For example, if the tank 30 is rectangular, it is preferable that the height is greater than each side of the bottom surface. If the tank 30 is cylindrical, it is preferable that the height is greater than the diameter of the bottom surface. If the tank 30 has another shape, it is preferable that the height is greater than the square root of the cross-sectional area of ​​the tank 30. However, the dimensions of the tank 30 are not limited to these.

[0048] Furthermore, the closer the filter 42 is disposed to the bottom surface of the tank 30, the longer it takes for the air bubbles 44 to escape from the liquid 32. Therefore, for example, the filter 42 may be embedded in the bottom surface of the tank 30.

[0049] 4 is a cross-sectional view that schematically shows a modified constant temperature liquid supply device 24a. In the modified constant temperature liquid supply device 24a, a filter 42a is embedded in the bottom surface of the tank 30, and the compressed gas supply pipes 36, 40 that reach the tank 30 are connected to this filter 42a. Air bubbles 44 released from the filter 42a travel the entire height from the bottom surface of the tank 30 to the upper surface of the liquid 32, so that the liquid 32 is cooled by the air bubbles 44 with high efficiency.

[0050] Returning to Figure 3, the constant temperature liquid supply device 24 will be further described. When air bubbles 44 are released from the filter 42 into the liquid 32, a current is generated in the liquid 32 as the air bubbles 44 move. This causes the liquid 32 contained in the tank 30 to be stirred, making it easier for the temperature to become uniform. A thermometer 50 is provided inside the tank 30, and this thermometer 50 monitors the temperature of the liquid 32.

[0051] For example, if the temperature of the liquid 32 measured by the thermometer 50 is significantly higher than the target temperature, the opening of the regulator 38 is increased to increase the supply pressure of the compressed gas, thereby increasing the amount of bubbles 44 and strongly cooling the liquid 32. On the other hand, if the temperature of the liquid 32 measured by the thermometer 50 is slightly higher than the target temperature, the opening of the regulator 38 is decreased to reduce the supply pressure of the compressed gas and slow down the cooling of the liquid 32 in order to avoid excessive cooling of the liquid 32.

[0052] In this way, the strength of the cooling effect of the bubbles 44 on the liquid 32 can be changed by operating the regulator 38 to change the supply pressure of the compressed gas to the filter 42. Basically, the cooling effect can be strengthened by increasing the supply pressure of the compressed gas.

[0053] However, it has been confirmed that this cooling effect tends to plateau once a certain pressure is reached. One reason for this is thought to be that the internal structure of the filter 42 places a limit on the amount of bubbles 44 that the filter 42 can release. If the supply pressure of compressed gas to the filter 42 is increased beyond the pressure limit of the filter 42, the filter 42 or the compressed gas supply pipes 36, 40 may be damaged.

[0054] On the other hand, if the supply pressure of the compressed gas to the filter 42 is too low, the temperature drop due to the expansion of the compressed gas released into the liquid 32 will be too small, and the liquid 32 will not be sufficiently cooled. Therefore, the supply pressure of the compressed gas to the filter 42 is preferably, for example, 0.25 MPa or more and 0.38 MPa or less. However, the supply pressure is not limited to this.

[0055] When the temperature of the liquid 32 measured by the thermometer 50 falls within an allowable range, it is confirmed that the liquid 32 contained in the tank 30 has become suitable for supply to the cutting device (processing device) 2. A liquid supply path 46 is connected to the tank 30, and a pump 48 is connected to the end of the liquid supply path 46. The pump 48 has the function of sucking the liquid 32 out of the tank 30, and the function of sending the liquid 32 from the constant temperature liquid supply device 24 to a predetermined external target.

[0056] The constant temperature liquid supply device 24 is connected to the cutting device (processing device) 2, for example, via a liquid supply pipe 26. When the liquid 32 reaches an appropriate temperature, the pump 48 is operated, whereby the liquid 32 is sucked out of the tank 30 and supplied to the cutting device (processing device) 2 via the liquid supply pipe 26.

[0057] The liquid 32 sent to the cutting device 2 passes through, for example, piping provided inside the cutting unit 16, and cools the rotary drive source that rotates the cutting blade 22, thereby maintaining the liquid at a predetermined temperature. The liquid 32, whose temperature has increased by absorbing heat from the rotary drive source, is preferably returned to the tank 30 of the constant-temperature liquid supply device 24 through a reflux pipe (not shown).

[0058] The returned liquid 32 is then cooled in the tank 30 by the air bubbles 44 released from the filter 42, and is then sent again to the cutting device (processing device) 2. In other words, the liquid 32 functions as a refrigerant that circulates between the cutting device (processing device) 2 and the constant temperature liquid supply device 24.

[0059] However, the use of the liquid 32 sent from the constant temperature liquid supply device 24 is not limited to a refrigerant, but may be used for other purposes, and the used liquid 32 does not have to be returned to the tank 30 of the constant temperature liquid supply device 24.

[0060] In the cutting device (processing device) 2, cutting fluid (machining fluid) is supplied from a cutting fluid supply nozzle 28 to the cutting blade (processing tool) 22 and the workpiece 1 while cutting the workpiece 1. If the cutting fluid is not at a constant temperature, it will cause variations in the processing results. Therefore, it is preferable to use liquid at a predetermined temperature sent from a constant temperature liquid supply device 24 as the cutting fluid (machining fluid).

[0061] However, used cutting fluid (machining fluid) contains a large amount of machining debris, and it is inappropriate to return it to the tank 30 of the constant temperature liquid supply device 24 without first purifying it. Therefore, the used cutting fluid does not need to be returned to the constant temperature liquid supply device 24. In this case, if the constant temperature liquid supply device 24 continues to operate, the amount of liquid 32 contained in the tank 30 will decrease.

[0062] If the amount of liquid 32 contained in the tank 30 decreases, the travel path of the gas bubbles 44 released from the filter 42 to reach the upper surface of the liquid 32 becomes shorter, and it is conceivable that the cooling effect of the gas bubbles 44 on the liquid 32 will decrease. Therefore, it is preferable that the tank 30 be replenished with liquid 32 from an external liquid supply source to maintain a constant amount of liquid 32 contained in the tank 30. Furthermore, even when used liquid 32 is returned to the tank 30, the liquid 32 evaporates and decreases, so it is preferable that the tank 30 be replenished with liquid 32 from an external source.

[0063] The liquid 32 replenished to the tank 30 from an external liquid supply source may be mixed with compressed gas from the compressed gas supply pipe 36, supplied to the filter 42, and released from the filter 42. When the mixed fluid of compressed gas and replenishment liquid is released from the filter 42, bubbles 44 are ejected with increased momentum into the liquid 32 contained in the tank 30, causing the bubbles 44 to spread widely throughout the liquid 32, which may enhance the cooling effect of the bubbles 44.

[0064] As explained above, in the constant temperature liquid supply device 24 according to this embodiment, the liquid 32 contained in the tank 30 can be cooled by compressed gas bubbles 44. In other words, because the liquid 32 can be cooled with just a simple configuration, there is no need for a large-scale cooling means that runs on electricity. This allows the constant temperature liquid supply device 24 to be made smaller. Furthermore, the electricity and power required to operate the constant temperature liquid supply device 24 are extremely small, which reduces operating costs.

[0065] The present invention is not limited to the above-described embodiments and can be practiced with various modifications. For example, in the above-described embodiments, the liquid 32 contained in the tank 30 is cooled only by compressed gas bubbles 44, but the constant temperature liquid supply device 24 according to one aspect of the present invention is not limited to this. In other words, the constant temperature liquid supply device 24 may be equipped with an electrically operated cooling device, and the liquid 32 contained in the tank 30 may be cooled by the cooling device.

[0066] When the temperature of the liquid 32 contained in the tank 30 is much higher than the target temperature, it takes time for the temperature of the liquid 32 to reach the predetermined temperature if the liquid 32 is cooled only by the gas bubbles 44. Therefore, it may be impossible to supply the liquid 32 at the predetermined temperature to the processing equipment at the timing required by the processing equipment.

[0067] Therefore, for example, a Peltier element that runs on electricity and cools the liquid 32 may be provided inside the tank 30. Alternatively, the constant temperature liquid supply device 24 may include an air blower that blows air onto the outer surface of the tank 30 to air-cool the tank 30. Using these cooling devices that run on electricity allows the liquid 32 contained in the tank 30 to be rapidly cooled.

[0068] However, even in this case, the operation of the cooling device can be minimized by stopping the operation of the cooling device and cooling the liquid 32 with the bubbles 44 when the temperature of the liquid 32 approaches a predetermined temperature, thereby allowing the liquid 32 to be cooled efficiently.

[0069] In addition, the structures, methods, etc. according to the above-described embodiments and modifications can be modified as appropriate without departing from the scope of the present invention. [Explanation of symbols]

[0070] 1 Workpiece 1a surface 1b back side 3 Planned division line 3a split groove 5 Devices 7 Ring Frame 9 Dicing Tape 11 Frame Unit 2 Cutting equipment 4 Foundation 4a aperture 6,8 Dustproof and water-resistant cover 10 Chuck table 10a Holding surface 10b Clamp 12 Support structure 14 Cutting unit movement mechanism 16 Cutting unit 18 Spindle housing 19 Chuck table 20 Blade Cover 22 Cutting blade 24,24a Constant temperature liquid supply device 26 Liquid delivery tube 28 Cutting water supply nozzle 30 Tank 30a Ventilation hole 32 liquid 34 Compressed Gas Source 36 Compressed gas supply pipe 38 Regulator 40 Compressed gas supply pipe 42,42a filter 44 Bubbles 46 Liquid transport path 48 Pump 50 thermometer

Claims

1. A constant temperature liquid supplying device that supplies a temperature-adjusted liquid to a processing device having a processing unit having a spindle to which a processing tool is attached and a motor that rotates the spindle, A tank for containing the liquid; a thermometer for measuring the temperature of the liquid contained in the tank; a compressed gas supply pipe having one end connected to a compressed gas source that stores compressed gas and the other end reaching the tank, for supplying the compressed gas from the compressed gas source to the tank; The height of the tank is greater than the square root of the cross-sectional area of ​​a cross section parallel to the bottom surface of the tank; A constant temperature liquid supplying apparatus, characterized in that the liquid contained in the tank is cooled by bubbles of the compressed gas, and the cooled liquid is supplied to the processing equipment.

2. A constant temperature liquid supplying device that supplies a temperature-controlled liquid to a processing device having a processing unit having a spindle to which a processing tool is attached and a motor to rotate the spindle, a rectangular parallelepiped tank for containing the liquid; a thermometer for measuring the temperature of the liquid contained in the tank; a compressed gas supply pipe having one end connected to a compressed gas source that stores compressed gas and the other end reaching the tank, for supplying the compressed gas from the compressed gas source to the tank; The height of the tank is greater than the length of each side of the bottom surface of the tank; A constant temperature liquid supplying apparatus, characterized in that the liquid contained in the tank is cooled by bubbles of the compressed gas, and the cooled liquid is supplied to the processing equipment.

3. 3. The constant temperature liquid supply device according to claim 1, further comprising a filter connected to the other end of the compressed gas supply pipe for discharging the supplied compressed gas into the liquid as bubbles.

4. A constant temperature liquid supplying device as described in any one of claims 1 to 3, characterized in that the liquid supplied to the processing device cools the processing unit, then returns to the tank, is cooled by the air bubbles, and is circulated by being supplied again to the processing device.

5. 5. The constant temperature liquid supplying apparatus according to claim 1, wherein the liquid supplied to the processing device is supplied to the processing tool and utilized as a processing liquid.

6. The liquid is pure water, The compressed gas is compressed air.

6. The constant temperature liquid supply device according to claim 1,

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