JPH0442915Y2 - - Google Patents

Description

[Detailed explanation of the idea]

"Industrial Application Field" The present invention relates to an apparatus for heat exchange of semiconductor processing liquids such as etching liquids. "Prior art" In order to control the temperature of the semiconductor processing solution, a circulation path with a heat exchanger and a pump is connected to the processing tank, and the semiconductor processing solution flowing from the processing tank is exchanged with the heat exchanger. After that, it is returned to the treatment tank. In this case, the temperature of the semiconductor processing liquid in the processing tank is detected by the temperature sensor, and the temperature of the heat exchange medium (for example, water) in the heat exchanger is controlled so that the temperature detected by the sensor becomes the target temperature. Ru. [Problems to be Solved by the Invention] However, the capacity of the heat exchanger for semiconductor processing liquid is quite large, which has conventionally caused the following problems. In other words, when the temperature detected by the sensor reaches the target temperature, the temperature of the processing liquid in the processing tank and the temperature of the processing liquid stored in the heat exchanger are different due to the influence of the bus from the heat exchanger to the processing tank. It makes a difference. Therefore, if a large amount of processing liquid stored in the heat exchanger flows into the processing tank after the above-mentioned point, the temperature of the processing liquid in the processing tank changes from the target temperature,
As a result, the temperature of the heat exchange medium of the heat exchanger is controlled in the opposite direction. In other words, temperature control with hunting is performed, and it takes time for the target temperature of the processing liquid in the processing tank to be established. An object of the present invention is to provide a heat exchange device that can set the temperature of the processing liquid in the processing tank as quickly as possible. [Means for Solving the Problems] The heat exchange device according to the present invention includes a first heat exchange means, heat exchanges the semiconductor processing liquid flowing out from the processing tank with the first heat exchange means, and then heats the semiconductor processing liquid again. A first circulation path returning to the processing tank and a second heat exchange means including a heating and cooling element are interposed, and the heat exchange medium heat exchanged by the second heat exchange means is transferred to the first heat exchange medium. a first temperature detection means for detecting the temperature of the semiconductor processing liquid in the processing tank; and a second temperature detection means for detecting the temperature of the heat exchange medium. A target temperature setting means for setting a target temperature of the semiconductor processing liquid in the processing tank compares the target temperature with the detected temperature of the first temperature detecting means, and the value of the detected temperature is determined to be the target temperature. a comparison means for determining whether or not the detected temperature is outside a predetermined temperature range centered at and controlling the heating/cooling means so that the detected temperature of the second temperature detecting means approaches the target temperature when the value of the detected temperature is within the temperature range. There is. [Function] According to this heat exchange device, when the temperature detected by the first temperature detection means is outside the above temperature range, the heating and cooling means is controlled based on the temperature detected by the first temperature detection means. Ru. Further, when the detected temperature of the first temperature detection means is within the above temperature range,
The heating and cooling means are controlled based on the temperature detected by the second temperature detection means. "Embodiments" Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 conceptually shows an embodiment of a heat exchange device according to the present invention. This embodiment includes a heat exchange tank 2 in which a coiled pipe 1 is disposed. The pipe 1 is made of a treatment liquid-resistant material such as Teflon, and one end of the pipe 1 is connected to the bottom of the inner tank 4A of the treatment tank 4 via the management 3, and the other end is connected to the bottom of the inner tank 4A of the processing tank 4 via the pipe line 5. They are each connected to the outer tank 4B of the processing tank 4. Note that a pump 6 is interposed in the middle of the pipe line 5. Moreover, pleats are formed on the outer periphery of the pipe 1. The chemical circulator 7 is composed of a heat exchanger 8 and a temperature control circuit 9, as shown in FIG. The heat exchanger 8 includes a passage 81 through which a constant temperature liquid serving as a heat exchange medium passes, thermo modules 82, 82 provided on both sides of this passage 81, and a radiator 83 attached to each of these thermo modules. , 83 and a temperature sensor 84 disposed within the passage 81. And the above passage 8
One end and the other end of 1 are connected to conduits 10 and 11, respectively.
It is connected to the upper and lower parts of the tank 2 via. Note that a pump 12 is interposed in the pipe line 11. The thermomodules 82, 82 perform electronic cooling or heating using semiconductor thermoelectric elements, and by changing the polarity of the applied voltage, the cooling action and the heating action can be switched. In addition,
Since the structure and operating principle of this thermomodule are well known, their explanation will be omitted here. The heat radiators 83, 83 radiate the heat generated by the thermo module, and are cooled by tap water. The comparison circuit 91 provided in the temperature control circuit 9 is
A sensor 13 that detects the temperature of the processing liquid in the processing tank 4
The output of the temperature setting device 92 is compared with the output of the temperature setting device 92, and when the difference between the respective outputs is greater than a certain value, the changeover switch 93 is switched to the contact b side. In this embodiment, when the difference between the target temperature of the processing liquid in the processing tank 4 set by the temperature setting device 92 and the temperature of the processing liquid detected by the sensor 13 is ±1° or more, The operating point of the comparator circuit 91 is determined so that the switch 93 is switched to the contact b side. In this embodiment, for example, water is poured into the tank 2 as a constant temperature liquid, and then the pump 12
When activated, water in the tank 2 is circulated through a circulation path consisting of the pipe 11, the passage 81 of the heat exchanger 9, and the pipe 10. Further, when the pump 6 is operated, the semiconductor processing liquid in the processing tank 4 is circulated through the circulation path consisting of the pipe 5, the pipe 1, and the pipe 3. Therefore, the semiconductor processing liquid circulating in the pipe 1 undergoes heat exchange with the water in the tank. Next, the operation of the temperature control circuit 9 will be explained.
Now, the temperature set by the temperature setting device 92 is, for example, 23°C, and the temperature of the semiconductor processing liquid in the processing tank 4 is
Assuming that the temperature is 20° C., the changeover switch 93 is switched to the contact b side, whereby the output of the sensor 13 and the output of the setting device 92 are applied to the thermomodule drive circuit 94. Therefore, the drive circuit 94 heats the thermomodule 82 so that the difference between the outputs thereof becomes small. In other words,
By heating the water passing through the heat exchanger 8, the temperature of the water in the tank 2 is increased, thereby increasing the temperature of the semiconductor processing liquid passing through the pipe 1. By the way, when temperature control is performed using only the output of the sensor 13, the following problems occur. That is, in this case, after the temperature of the semiconductor processing liquid in the processing tank 4 reaches 23°C, a considerable amount of the processing liquid that had passed through the pipe 1 will flow into the processing tank 4. A phenomenon occurs in which the temperature of the processing liquid in the processing tank 4 becomes higher than the set temperature of 23° C., and therefore the thermomodule 82 is operated to lower the temperature of the processing liquid. In other words, a hunting phenomenon occurs until the temperature is stabilized, and the settling time becomes longer. However, in the above embodiment, the switch 93 is connected to the contact a side when the temperature of the processing liquid in the processing tank 4 rises from 20°C to 22°C. is added to the drive circuit 94, the temperature settling time can be shortened. In other words, the output of the sensor 84 indicates approximately the temperature of the water in the tank 2, and since the temperature of this water is higher than 23°C, the thermo module 82 is activated for cooling.
As a result, the processing liquid in the processing tank 4 is quickly settled to around 23°C, and at that point, the temperature of the processing liquid in the processing tank and the temperature of the processing liquid in the pipe 1 become almost equal, and the temperature in the tank 1 becomes almost equal. The temperature of the water is in equilibrium. Note that at this point, the heating or cooling action of the thermomodule 82 is almost stopped. Thus, according to this embodiment, extremely stable temperature control of the processing liquid can be performed. In the above embodiment, the thermomodule 82 is used as a heating/cooling means for temperature control, but the present invention can be implemented by using other general-purpose heating/cooling means instead. Further, in the above embodiment, the difference between the temperature of the processing liquid in the processing tank 4 and the set temperature is ±1°C.
The switch 93 is switched to the contact b side when the temperature difference exceeds the threshold value, but the threshold range for this temperature difference is the amount of semiconductor processing liquid, the heating and cooling capacity of the heat exchanger 8, and the amount of constant temperature liquid. It is set to a desired value as appropriate depending on the situation. Note that the tank 2, the passage 81 of the heat exchanger 8,
Preferably, the pipes 10, 11, etc. are made of a material resistant to processing liquid in case the semiconductor processing liquid leaks from the pipe 1. Examples of the semiconductor processing liquid include etching liquids, etc. Typical etching liquids heat exchanged by the apparatus of the present invention are exemplified by use as follows.

[Table] "Effects of the invention" According to the heat exchange device according to the invention, the temperature of the processing liquid in the processing tank is set to the target temperature as quickly as possible, so etching processing etc. can be carried out efficiently and appropriately. be able to.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram showing an embodiment of a heat exchange device according to the present invention, and FIG. 2 is a conceptual diagram showing an example of the configuration of the circulator shown in FIG. 1. 1...pipe, 2...tank, 4...processing tank,
6, 12...Pump, 7...Chemical circulator, 8...Heat exchanger, 9...Temperature control circuit, 1
3, 84... Temperature sensor, 91... Comparison circuit, 9
2... Temperature setting device, 93... Changeover switch, 94
...Thermo module drive circuit.

Claims (1)

[Claims for Utility Model Registration] A first circulation path in which a first heat exchange means is interposed, and the semiconductor processing liquid flowing out from the processing tank is heat exchanged with the first heat exchange means and then returned to the processing tank. and a second circulation path in which a second heat exchange means equipped with a heating and cooling element is interposed and supplies the heat exchange medium heat exchanged by the second heat exchange means to the first heat exchange means. , a first temperature detection means for detecting the temperature of the semiconductor processing liquid in the processing tank; a second temperature detection means for detecting the temperature of the heat exchange medium; and a first temperature detection means for detecting the temperature of the semiconductor processing liquid in the processing tank. a target temperature setting means for setting a target temperature of the first temperature detecting means; and a target temperature setting means for setting a target temperature of a comparison means for determining whether or not a value of the detected temperature exists, and a comparison means for controlling the heating and cooling means so that the detected temperature approaches the target temperature when the value of the detected temperature is outside the temperature range, and the value of the detected temperature; and a control means for controlling the heating and cooling means so that the temperature detected by the second temperature detection means approaches the target temperature when the temperature is within the temperature range. Device.