JP4511900B2 - Cleaning liquid heating apparatus and cleaning liquid heating method using the same - Google Patents

Description

  The present invention relates to a cleaning liquid heating apparatus and a cleaning liquid heating method using the same particularly for cleaning a wafer or the like in a semiconductor manufacturing process. More specifically, the cleaning liquid can be heated without mixing impurities or the like. The present invention relates to a cleaning liquid heating apparatus and a cleaning liquid heating method using the same.

  As is well known, semiconductors are manufactured through various processes. In particular, in the process of manufacturing a chip incorporating a circuit, cleaning of a wafer is indispensable, and for printing used to transfer a pattern to a wafer. Even with a mask, it is essential to clean it before use.

  And, when cleaning this wafer or the like, it is generally performed using a cleaning liquid such as ultrapure water, and at the time of cleaning, the cleaning liquid is used at a high temperature in order to increase the cleaning capability. It has been common to heat this cleaning solution using a heater.

  That is, FIG. 3 is a diagram showing a schematic configuration of the cleaning liquid heating device 31 using a heater. In the figure, 32 is a heating tank for heating the ultrapure water 33 supplied to the inside. An ultrapure water production plant 34 is connected to the tank 32 through an ultrapure water line 35, and ultrapure water 33 produced in the ultrapure water production plant 34 is passed through the ultrapure water line 35. It is supplied to the heating tank 32.

  The heating tank 32 is connected to a supply line 37 for supplying heated ultrapure water 33 to the wafer cleaning process, and a pump 38 is provided at an arbitrary position of the supply line 37. Thus, by operating the pump 38, the ultrapure water 33 heated to a predetermined temperature can be supplied to the cleaning process.

  When the cleaning liquid such as ultrapure water is heated using the cleaning liquid heating apparatus 31 configured as described above, heating is performed in the ultrapure water 33 supplied to the heating tank 32 via the ultrapure water line 35. The heater 36 is immersed, and the ultrapure water 33 is heated by the heater 36.

That is, in general, when heating a cleaning liquid used for cleaning a wafer or the like, the cleaning liquid is supplied into a heating tank, and a heating means such as a heater is directly immersed in the cleaning liquid in the heating tank. Thereby, the cleaning liquid was heated.
JP 05-190523 A JP 07-294000 A JP 11-290799 A

  However, in the conventional heating method, a problem has been pointed out that a cleaning liquid such as ultrapure water takes in dust in the heating tank. In particular, when ultrapure water was used as a cleaning liquid and a metallic heating tank was used, there was a high risk that ultrapure water would take in metal ions in the heating tank.

  Further, in the conventional method, in order to immerse the heating means such as a heater directly in the cleaning liquid, that is, in order to heat the cleaning liquid rapidly by bringing a high temperature heater or the like into direct contact with the normal temperature cleaning liquid, thereby the cleaning liquid Oxygen inside appears as bubbles, and there is a risk that the cleaning liquid containing bubbles will be supplied to the cleaning process. In such a case, a watermark is formed on the wafer, which is erased. It has also been pointed out that this is impossible.

  On the other hand, since the resolution of semiconductor patterns has been greatly improved due to recent technological innovations, even a small amount of dust can cause defective products. Specifically, even when 0.1 micron dust adheres, In order to become a non-defective product, it is necessary to avoid contamination of the cleaning liquid with dust.

  Therefore, an object of the present invention is to provide a cleaning liquid heating apparatus and a cleaning liquid heating method using the cleaning liquid heating apparatus that can heat the cleaning liquid to a predetermined temperature while effectively preventing contamination of the cleaning liquid.

The cleaning liquid heating apparatus of the present invention is
A heating tank in which a part of the cleaning liquid line is disposed;
A city water supply line for supplying city water to the heating tank;
Both ends are opened inside the heating tank, city water in the heating tank is supplied from the opening at one end, and the circulated city water can be discharged into the heating tank from the opening at the other end. , a city water circulation line for circulating tap water supplied to the heating tank,
A heater for heating the city water circulating through the city water circulation line ;
A temperature sensor for monitoring the temperature of the heated tap water by the heater,
A plurality of disposed in the inside of the heating tank, and a hollow drainage tower that closes the top and opens the bottom and forms a number of drainage holes in the side wall, and
Branching the outlet of the city water circulation line to the number of drainage towers, and in the heating tank, on the bottom side of each drainage tower, arranging the outlet of the city water circulation line branched,
The number of the cleaning liquid lines arranged in the heating tank is the same as the number of the drainage towers, and the part arranged in the heating tank in each cleaning liquid line is provided around the outer periphery of each draining tower. ,
While supplying city water heated by the heater for heating from the bottom of each drainage tower to the inside of the drainage tower, it drains into the heating tank through the drainage hole, and into the heating tank through the drainage hole. The cleaning liquid moving in the cleaning liquid line can be heated by the city water to be drained .

  When the cleaning liquid is heated according to the present invention, first, city water is supplied into the heating tank, and the supplied city water is circulated while being heated.

  At the same time, the cleaning liquid is moved in the cleaning liquid line, so that the cleaning liquid moving in the cleaning liquid line can be heated by the temperature of the city water.

  As described above, in the present invention, the city water supplied to the heating tank is heated, and the cleaning liquid that partially moves in the cleaning liquid line disposed in the heating tank using the heat of the heated city water. Unlike the conventional heating method, a heater or the like is not directly immersed in the cleaning liquid. For this reason, it is possible to effectively prevent metal ions in the heating tank from dissolving in the cleaning liquid, and since the cleaning liquid is not directly and rapidly heated, oxygen in the cleaning liquid appears as bubbles. Can be effectively prevented. Therefore, by using the present invention, the cleaning liquid can be heated without mixing dust.

  In the present invention, a heating tank is provided, and a part of the cleaning liquid line through which the cleaning liquid moves is disposed in the heating tank.

In the present invention, a city water supply line for supplying city water to the heating tank is provided, and a city water circulation line for circulating the city water supplied to the heating tank is provided. .

Further, in the present invention, a heating heater for heating the circulating city water and a temperature sensor for monitoring the temperature of the circulating city water while being heated are provided.

  And, with this configuration, it is possible to supply city water into the heating tank, circulate the supplied city water while heating, move the cleaning liquid in the cleaning liquid line, and thereby heat the cleaning liquid Yes.

Here, it is preferable that the city water circulation line is provided with a heat exchanging means, thereby adjusting the temperature of the city water circulated through the city water circulation line .

Moreover, it is good to equip the said heating tank with a drainage means, and to make the operation | work at the time of discharging the city water in a heating tank easy by this.

  Further, as the cleaning liquid line, it is preferable to use a thin-walled tube formed of a fluorine-based resin, which can increase the thermal conductivity.

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram for explaining the configuration of the present embodiment. In the figure, 1 is a heating tank used for heating the cleaning liquid.

  A part of the cleaning liquid line is disposed inside the heating tank 1. That is, in the figure, reference numeral 2 denotes a cleaning liquid line. In this embodiment, ultrapure water is used as the cleaning liquid, and this cleaning liquid line 2 is an ultrapure water line. The cleaning liquid line 2 has one end connected to the ultrapure water production plant and the other end connected to a cleaning tank or the like in the wafer cleaning process. It is possible to supply the ultrapure water produced in step 1 to the cleaning step after heating through the heating tank 1. In the figure, reference numeral 201 denotes a temperature sensor for monitoring the temperature of the cleaning liquid moving in the cleaning liquid line 2.

  In the present embodiment, as the ultrapure water line, a thin tube formed of a fluorine-based resin is used, and the surface thereof has a jagged shape, thereby increasing the thermal conductivity. . In this example, a tube formed of Teflon (registered trademark) was used as an ultrapure water line formed of a fluorine-based resin.

Next, in the figure, 3 is a city water supply line, that is, in this embodiment, a city water supply in which the front end is opened in the heating tank 1 and a city water supply source is connected to the base end. A line 3 is provided, and city water can be supplied into the heating tank 1 through the city water supply line 3. In the figure, reference numeral 301 denotes a city water supply valve interposed at an arbitrary location of the city water supply line 3. By the action of the city water supply valve 301, the city water is supplied to the heating tank 1 or The supply can be stopped.

Next, a city water circulation line is connected to the heating tank 1, that is, 4 in the figure is a city water circulation line. In this embodiment, the city water circulation line 4 has both ends at the ends of the heating tank 1. It is opened inside, and city water in the heating tank 1 is supplied from the opening (inlet) at one end, and the circulated city water can be discharged into the heating tank 1 from the opening (outlet) at the other end. .

  In the present embodiment, a circulation pump 5 and a heater 6 are provided at any location of the city water supply line 4, and thereby the city water in the heating tank 1 is provided by the circulation pump 5. The city water circulated by the heater 6 can be heated while circulating the water.

  In the figure, reference numeral 7 denotes a temperature sensor. That is, in the present embodiment, a temperature sensor 7 is provided at an arbitrary position of the circulation line 4 so that the temperature of the circulating city water can be monitored. Yes.

  In the figure, reference numeral 401 denotes a circulation valve. That is, in this embodiment, a circulation valve 401 is provided at an arbitrary position of the city water circulation line 4, and circulation is started by the action of the circulation valve 401. Or it can be stopped.

  Furthermore, 8 is a heat exchange means in the figure. In this embodiment, the bypass line 402 is formed in the city water circulation line 4, and the heat exchange means 8 is interposed at an arbitrary portion of the bypass line 402. In addition, a bypass valve 403 for circulating city water through the heat exchange means 8 side is interposed. Thus, when the temperature of the city water is lowered based on the temperature monitored by the temperature sensor 7, the temperature is lowered by the heat exchange means 8 by circulating the city water through the bypass line 402. Making it possible.

  In the present embodiment, the heat exchanging means 8 has a configuration in which a circulation chamber 802 and a cooling chamber 803 are formed by partitioning the inside thereof with a partition wall 801, and city water is moved in the circulation chamber 802 to cool it. In the chamber 803, the cooling water is circulated using the cooling water line 11 provided with the cooling water valve 1101 at an arbitrary location, and thereby circulated through the city water circulation line 4 via the partition wall 801. It is possible to reduce the temperature of the city water by absorbing the heat of the city water to the cooling chamber 803 side.

Next, inside the heating tank 1, a plurality of hollow drain towers 9 are provided which close the top and open the bottom, and further have a number of drain holes 901 formed on the side walls.

In this embodiment, the outlet of the city water circulation line 4 is branched into the number of the drainage towers 9, and the city water circulation branched in the heating tank 1 on the bottom side of each drainage tower 9. The outlet of the line 4 is arranged, whereby the city water heated by the heater 6 is supplied to the inside of the drainage tower 9 from the bottom of each drainage tower 9, and the heating tank 1 through the drainage hole 901. It has a structure that can be drained inside.

Then, in this embodiment, the portion of the cleaning liquid line 2 disposed at least in the heating tank 1, as well as to the drainage column 9 the same few, into the heating chamber 1 in each of the cleaning liquid line 2 The arranged portion is provided around the outer periphery of each drainage tower 9. Thus, the cleaning liquid moving in the cleaning liquid line 2 can be heated by the heated city water discharged from the drain hole 901 while being supplied into the drain tower 9.

  In the figure, 10 is a float switch for monitoring the water in the heating tank 1, and in this embodiment, the amount of city water supplied into the heating tank 1 is determined by using this float switch 10. Monitoring.

  In the figure, reference numeral 12 denotes a drain line, that is, in this embodiment, the drain line 12 provided with a drain valve 1201 is connected to the heating tank 1, whereby the city water in the heating tank 1 is discharged. It facilitates the work when discharging.

  Next, FIG. 2 shows a control system in the case of automatically controlling the cleaning liquid heating apparatus of the present embodiment. In the case of automatically controlling the operation of the cleaning liquid heating apparatus of the present embodiment, the city water supply valve 301 is shown. The circulation valve 401, the bypass valve 403, the cooling water valve 1101 and the drain valve 1201 are connected to a control unit such as a CPU so that these valves can be automatically controlled, and the float switch 10 is used as the control unit. In the heating tank 1, the city water temperature sensor 7 that connects and adjusts the supply amount of city water according to the water level of the city water in the heating tank 1 and monitors the temperature of the circulating city water. Although not shown, the ultrapure water temperature sensor 201 for monitoring the temperature of the heated ultrapure water, an operation switch, and the like, the circulation pump 5, the heater 6 and the like are connected to the control unit. Circulation La The heating heater 6 may be adjusted or cooled by the heat exchanging means 8 according to the temperature of city water circulating in the tank 2 and the temperature of ultrapure water moving in the ultrapure water line 2. .

  Next, an example of a method of heating the cleaning liquid using the cleaning liquid heating apparatus of the present embodiment configured as described above will be described. When heating the cleaning liquid using the cleaning liquid heating apparatus of the present embodiment, The city water supply valve 301 is opened to supply city water 13 into the heating tank 1, and the water level of the city water 13 supplied into the heating tank 1 is monitored by the float switch 10. When the city water 13 reaches a predetermined amount, the city water supply valve 301 is closed to stop the city water supply.

At the same time, the circulation valve 401 is opened, the circulation pump 5 and the heater 6 are operated, and the city water 13 in the heating tank 1 is circulated. Heating is performed by the heater 6 while monitoring the temperature by the temperature sensor 7.

  Furthermore, while heating the city water 13 in the heating tank 1 in this way, it circulates, and while moving the ultrapure water for cleaning from the ultrapure water production plant to the cleaning process via the cleaning liquid line 2, the heating tank The temperature sensor 201 monitors the temperature of the ultrapure water moving from 1.

  Then, the city water 13 heated by the heater 6 is supplied from the bottom of the drainage tower 9 to the inside of the drainage tower 9 and drained from the drainage hole 901 in the heating tank 1. It is possible to heat the ultrapure water that moves inside the ultrapure water line 2 that is provided in the periphery.

  At this time, since the ultrapure water line 2 is provided with the temperature sensor 201, the heater 6 is adjusted according to the temperature of the ultrapure water monitored by the temperature sensor 201. It becomes possible to raise to a predetermined temperature.

  On the other hand, when the temperature of the ultrapure water exceeds a predetermined temperature, the cooling valve 1101 and the bypass valve 403 are opened and the circulation valve 401 is closed. If it does so, the temperature of the circulating city water will be lowered | hung by the heat exchange means 8, and it will become possible to also reduce the temperature of an ultrapure water by this.

  Further, when the city water in the heating tank 1 is discharged due to the cleaning of the heating tank 1 or the deterioration of the quality of the city water in the heating tank 1, the drain valve 1201 is opened to easily open the inside of the heating tank 1. It becomes possible to discharge the city water.

  Thus, according to the cleaning liquid heating apparatus of the present embodiment, a part of the cleaning liquid line for moving the cleaning liquid is disposed inside the heating tank to which the city water is supplied, and the city water supplied into the heating tank is provided. Thus, it is possible to circulate while heating the cleaning liquid, thereby enabling the cleaning liquid to be heated by the heated city water.

  Therefore, unlike conventional devices that directly immerse heating means such as a heater in the cleaning liquid, the metal ions in the heating tank do not dissolve in the cleaning liquid, and the cleaning liquid is not directly heated. It is possible to effectively prevent the oxygen from appearing as bubbles, and thus it is possible to heat the cleaning liquid without mixing dust.

  The present invention employs a method of heating the cleaning liquid using heated city water, and in general heating of the cleaning liquid used for cleaning wafers, masks for baking, as well as products that must avoid adhesion of fine dust. It is possible to apply.

  Further, it can be applied not only to ultrapure water but also to heating of all cleaning liquids used for cleaning various products.

It is a block diagram for demonstrating the Example of the washing | cleaning liquid heating apparatus of this invention. It is a block diagram for demonstrating the control system in the Example of the washing | cleaning liquid heating apparatus of this invention. It is a block diagram for demonstrating the outline of the conventional washing | cleaning liquid heating apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heating tank 2 Ultrapure water line 201 Temperature sensor 3 City water supply line 301 City water supply valve 4 City water circulation line 401 Circulation valve 402 Bypass line 403 Bypass valve 5 Circulation pump 6 Heating heater 7 Temperature sensor 8 Heat Exchange means 801 Partition 803 Circulating chamber 803 Cooling chamber 9 Drain tower 901 Drain hole 10 Float switch 11 Cooling water line 1101 Cooling water valve 12 Drain line 1201 Drain valve 13 City water

Claims (4)

A heating tank (1) in which a part of the cleaning liquid line (2) is disposed;
A city water supply line (3) for supplying city water to the heating tank (1);
While opening both ends inside the heating tank (1), the city water in the heating tank (1) is supplied from the opening (inlet) at one end, and the circulating city water is opened at the other end. A city water circulation line (4) for circulating city water supplied to the heating tank (1), which can be discharged into the heating tank (1) from the (exit);
A heater (6) for heating city water circulating through the city water circulation line (4);
A temperature sensor (7) for monitoring the temperature of city water heated by the heater (6);
A plurality of hollow drain towers (9) disposed inside the heating tank (1), closing the top and opening the bottom and forming a number of drain holes (901) on the side wall; and
The outlet of the city water circulation line (4) is divided into the number of the drainage towers (9), and the city water circulation branched in the heating tank (1) on the bottom side of the drainage towers (9). Arrange the exit of the line (4),
The number of the cleaning liquid lines (2) arranged in the heating tank (1) is the same as the number of the drainage towers (9), and the respective cleaning liquid lines (2) arranged in the heating tank (1) ) Around each drain tower (9)
The city water heated by the heater (6) is supplied from the bottom of each drainage tower (9) to the inside of the drainage tower (9), and is supplied to the inside of the heating tank (1) through the drainage hole (901). The cleaning liquid heating is characterized in that the cleaning liquid moving in the cleaning liquid line (2) can be heated by city water discharged into the heating tank (1) through the drain hole (901). apparatus. The city water circulation line (4), according to claim 1, further comprising a heat exchange means (8) for adjusting the temperature of the city water circulated through the city water circulation line (4) Cleaning liquid heating device. The cleaning liquid heating apparatus according to claim 1 or 2, wherein the heating tank (1) is provided with drainage means (12).   The cleaning liquid heating apparatus according to any one of claims 1 to 3, wherein a thin tube formed of a fluorine-based resin is used as the cleaning liquid line (2).

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