KR100741475B1 - In-line heater of etching and cleaning solutions for semiconductor wafer - Google Patents

Abstract

An in-line heater for heating wet-etching and cleaning chemicals for a semiconductor wafer is provided to extend the lifetime of an in-line heater and easily perform a preventive maintenance of the in-line heater by basically preventing an electric heating wire from being corroded by chemicals. An in-line heater includes a receptacle, a liquid thermal medium(58), an electric heater(24a,24b) and a chemicals pipe(12). The liquid thermal medium is received in the receptacle. The electric heater heats the thermal medium, soaked into the thermal medium. The chemicals pipe is soaked into the thermal medium, chemicals for etching or cleaning a semiconductor wafer pass through the chemicals pipe so that a heat exchange between the thermal medium and the chemicals can be performed. A temperature sensor(46a,46b) is installed in the receptacle. A control part is installed in the in-line heater, capable of controlling the power of the electric heater. The control part automatically connects power to the electric heater if the temperature of the thermal medium in the receptacle is not higher than a predetermined temperature, and automatically blocks the power of the electric heater if the temperature of the thermal medium is not lower than the predetermined temperature. A thermal medium stirring unit is installed in the in-line heater to stir or convect the thermal medium so that the temperature of the thermal medium can be uniformly maintained in any position of the receptacle.

Description

IN-LINE HEATER OF ETCHING AND CLEANING SOLUTIONS FOR SEMICONDUCTOR WAFER}

1 is a block diagram of an inline heater and a peripheral device for heating a semiconductor wafer wet etching and cleaning chemical according to the present invention.

FIG. 2 is a perspective view showing an embodiment of an inline heater for heating a semiconductor wafer wet etching and cleaning chemical according to the present invention.

3 is an assembled perspective view of the inline heater for heating the semiconductor wafer wet etching and cleaning chemicals shown in FIG. 2.

4 is a cross-sectional view taken along the line AA ′ of FIG. 3.

            Explanation of symbols on the main parts of the drawings

10a, 10b: chemical tube roll 12: chemical tube

14a, 14b: head 16a, 16b: chemical tube roll support

18: cover 20: electric heater insertion hole

22: motor shaft insertion hole 24a, 24b: electric heater

26: stirring means 28: motor

30: motor shaft 32: impeller

34: tank 36: coke

38: water supply pipe 40: electronic valve

42a: flood pipe 42b, 42c: drain pipe

44a: drain socket 44b: flood pipe socket

46a, 46b: Temperature sensor 47: Chemical leak detection sensor

48: water level sensor 50: chemical injection pipe

52: chemical discharge pipe 54: pump

56: power 58: heat medium

60: control unit

The present invention relates to an inline heater for heating a semiconductor wafer wet etching and cleaning chemical, and more particularly, to a temperature required for a temperature of a chemical used in an etching process or a cleaning process by being connected to an etching apparatus or a cleaning apparatus in a semiconductor wafer processing apparatus. It relates to an in-line heater that can be compensated in real time.

Chemicals used in wafer etching or cleaning processes in semiconductor manufacturing processes are used in a state heated to a certain temperature for chemical activity. However, these chemicals are very corrosive and cannot be heated in a metal container, and heating heating wires cannot be in direct contact with the chemicals, and thus, various restrictions are applied in producing a heater for heating the chemicals.

Therefore, conventionally, the container, piping, etc. of the heater for chemical heating were all molded from fluorine resins such as polyvinylidene fluoride (PVDF) and polytetrafluoroethylene (PTFE, also known as "Teflon") having good chemical resistance. The heating of the chemicals was carried out in such a way as to infiltrate the heating wires inside the chemicals while passing the chemicals inside these fluororesin containers and to generate heat by flowing a current through the heating wires. At this time, the heating wire was also easily corroded by chemicals and easily disconnected, so the heating wire was inserted into the fluorine resin tube.

However, the fluorine resin is a crystalline resin, and there is a gap between the crystals and the chemical penetrates. Therefore, when the heating wire inserted into the fluorine resin tube is also used for a long time, the chemical penetrates to the heating wire, causing the heating wire to be corroded and disconnected and shortening the life of the heater.

Also, in recent years, as the directivity of semiconductors increases, the line width becomes extremely fine, and the size of the wafer increases in order to increase the yield per wafer, and the secondary process of spraying or etching chemicals while rotating the wafers one by one during the semiconductor production process is performed. It is getting bigger. Unlike in the past, when several wafers are transported in a chemical bath to be etched or cleaned at a time, chemicals are transferred to a single wafer etching or cleaning equipment in a recent semiconductor process that requires wafers to be processed sheet by sheet. After that, chemical treatment should be performed in the etching equipment or the cleaning equipment. However, it is very difficult to supply chemicals from chemical tanks to sheetfed etching equipment or cleaning equipment at a constant temperature. Therefore, with chemical equipment such as etching equipment or cleaning equipment, and inlined chemical heating device, supplying chemicals continuously while keeping them at the required temperature at the place where these equipments are kept is necessary for uniformity and efficiency of etching process and cleaning process. It is necessary. In addition, the chemical heating apparatus inlined with the etching or cleaning equipment should be able to raise the chemical to the required temperature within a short time even when the amount of chemicals is rapidly changed.

However, when the above-described chemical heating device using the fluorine resin container and the fluorine resin tube insertion heating wire is used as the inline heater, when the amount of the inlet heater changes, the temperature of the chemicals in the container may change due to the lack of the chemical residence time in the container. It is difficult to maintain the uniformity of etching or cleaning.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the conventional semiconductor wafer etching and cleaning chemicals heating device. The present invention provides an inline heater for heating a semiconductor wafer wet etching and cleaning chemical which can fundamentally block corrosion of a heating wire caused by chemicals. Its purpose is to.

Another object of the present invention is to inline the etching equipment or cleaning equipment for semiconductor wafer wet etching and cleaning chemicals heating that can heat the chemical to the temperature required within a short time when the amount of chemicals required for these equipment fluctuates To provide a heater.

Inline heater for heating a semiconductor wafer wet etching and cleaning chemicals in accordance with the present invention to achieve the above object is

Vessel; A liquid heat medium contained in the container; A heat transfer heater which is immersed in the heat medium to heat the heat medium; And a chemical tube made of a fluorine resin material which is immersed in the heat medium to allow heat of the heat medium to exchange heat with the chemical while passing through the semiconductor wafer etching or cleaning chemicals.

The chemical pipe is made of a plurality of fluorine resin tubing (細 管) in parallel, and both ends of the customs pipe is inserted and bonded to the head of the fluorine resin material through-hole formed in the flow path direction by the number of the tubing is connected to the chemical injection pipe or the chemical discharge pipe It is preferable.

The heat medium is water, it is preferable that the water supply pipe for replenishing the water and the flooding pipe for discharging when the water reaches a certain level.

In the container, it is preferable to further include a heat medium stirring means capable of stirring or convection the heat medium so that the temperature of the heat medium is uniformly maintained at any point.

The container or the chemical discharge pipe is provided with a temperature sensor, and a control unit for controlling the power supply of the heat transfer heater. When the temperature of the heat medium or the chemical discharge pipe in the container drops below a preset temperature, the power is supplied to the heat transfer heater. It is preferable to cut off the power of the electric heater when the connection is made and the temperature rises above the preset temperature.

Hereinafter, a preferred embodiment of an inline heater for heating a semiconductor wafer wet etching and cleaning chemical according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of an inline heater and peripheral devices for heating a semiconductor wafer wet etching and cleaning chemicals according to the present invention, Figure 2 is an embodiment of an inline heater for heating a semiconductor wafer wet etching and cleaning chemicals according to the present invention 3 is an assembled perspective view of the semiconductor wafer wet etching and cleaning chemical heating in-line heater shown in FIG. 2, and FIG. 4 is a cross-sectional view taken along the line AA ′ of FIG. 3, respectively.

Referring to FIG. 1, an in-line heater according to the present invention, in heating a chemical for etching or cleaning a semiconductor wafer, does not directly heat the chemical by the heat transfer heaters 24a and 24b, but the liquid in a liquid such as water contained in the container 34. The fruit liquid 58 is heated, and the heated fruit liquid 58 is characterized in that the medicine is heated by heat-exchanging with an etching or cleaning chemical circulated through the chemical pipe 12. That is, the in-line heater according to the present invention is characterized by heating the chemicals by employing a heat exchange method. To this end, the present invention is a container 34 capable of accommodating a fruit liquid such as water therein, a chemical tube 12 made of a fluorine resin material which is installed inside the container 34 and circulates the drug, and the container And a heat medium 58 which is filled in the 34 and heated to the heat transfer heaters 24a and 24b and then transfers the heat to the medicine passing through the medicine pipe 12. The medicine of the medicine pipe 12 is circulated by the pump 54 provided in the medicine injection pipe 50 or used directly in the process. According to the present invention, since the medicine is not filled in the container 34, the material does not need to be molded into a fluororesin having chemical resistance. However, the chemical pipe 12 is formed of fluorine resin because the medicine is circulated. In addition, the chemical tube 12 is preferably locked in the heat medium 58 while being wound in a roll shape in order to widen the contact interview with the heat medium.

The heat heater 24a, 24b is preferably made of a heat transfer rod shape, as shown in Figure 1 to be built inside the roll-shaped chemical pipe 12, but it is not necessarily to be manufactured in such a shape and the installation position It may also be a container bottom, a container inner wall, or the like. The electrothermal heaters 24a and 24b are connected to a power source 56, and the power source 56 is supplied by a separate control unit 60 according to the temperature of the heat liquid 58 as described later, and whether or not the current is supplied. This is preferably controlled automatically.

2 and 4, the medicine pipe 12 is composed of a plurality of parallel tubules, these customs pipes are fixed in the form of rolls on the drug pipe roll support (16a, 16b) to be installed inside the container 34 It is preferable to maximize the heat exchange area. In order for the heat exchange between the chemical flowing through the chemical pipe 12 and the heat medium 58 to be made well, the heat transfer area must be large, and thus, the customs pipe is extended to be wound and installed in a roll shape. However, the use of one very long tubule for the chemical pipe 12, the pressure loss inside the tubing increases, which causes a limitation in the drug feed rate. Therefore, if the pressure loss inside the chemical pipe is too large due to too long customs, it is desirable to increase the number of customs and reduce the length.

In addition, one chemical tube roll may be installed in one container 34, but two chemical tube rolls 10a and 10b may be installed as shown in FIG. 2, or more chemical tube rolls may be installed. However, even when two or more chemical pipe rolls are installed as shown in FIG. 1, both ends thereof are connected to a single injection pipe 50 and a discharge pipe 52.

In the case where the chemical pipe 12 is composed of a plurality of customs pipes, the heads 14a and 14b of the fluororesin material having through holes formed in the flow path direction by the number of the customs pipes are provided, so that both ends of the customs pipes are disposed on the heads 14a and 14b. It is preferable to insert after inserting into the through-hole of the). By configuring in this way, it is possible to easily connect a plurality of capillaries to a single inlet tube 50 or outlet tube 52.

4 shows a case where there are four customs forming the medicine tube 12. These tubules are wound tightly while maintaining a constant interval in and out of the chemical pipe roll support (16a, 16b), the heat transfer heater (24a, 24b) is provided in the center of the chemical pipe roll to effectively heat the heating medium around the chemical pipe (12) .

Referring to FIG. 2, it is preferable to further include a stirring means 26 in the container 34 to condense the heat medium so that the entire heat medium can be maintained at a uniform temperature at any point. As shown in FIG. 1 or FIG. 2, the stirring means 26 includes a motor 28 provided outside the container cover 18, an impeller 32 immersed in a heat medium 58 inside the container 34. It may be configured as a long motor shaft 30 connecting the motor 28 and the impeller 32, but is not limited to this, and install a submersible pump inside the container, or the heat medium in the container after mounting the pump outside It can be implemented in a variety of ways, such as circulating or using a submersible motor.

Referring back to FIG. 1, it is preferable to use a non-corrosive, high boiling point and specific heat liquid as the heat medium 58, and most preferably water. Therefore, below, only the case where water is used as a heat medium is demonstrated by way of example. According to the present invention, since the electric heaters 24a and 24b are immersed in water which is not highly corrosive, there is no need to coat the circumferential heaters with fluorine resin. In addition, the heat transfer heaters 24a and 24b are coated with an insulating material having better thermal conductivity than the fluorine resin, so that the water 58 can be heated in a short time with the same electric power. In addition, since the specific heat of the water 58 is large, a large amount of heat may be included, so that sufficient heat may be supplied even when a circulating speed of the chemical passing through the chemical pipe 12 is fast. The water can be vaporized and reduced when heated, the vessel 34 is further connected to the water supply pipe 38 for replenishing the reduced water vaporized and the overflow pipe 42a for discharging when the water exceeds a certain level. desirable. In addition, it is preferable to install drain 44a and drain pipes 42b and 42c provided with coke 36 at the bottom of the container so that water in the container 34 can be discharged through drain 44a as necessary. Do.

In-line heater is preferably the temperature of the water 58 or the chemical temperature of the discharge pipe 52 is automatically controlled. To this end, the in-line heater according to the present invention includes a temperature sensor (46a, 46b) in the container 34 or the chemical discharge pipe 52, the control unit 60 that can control the power of the heat transfer heater (24a, 24b) And the power source 56 is connected to the heat transfer heaters 24a and 24b when the temperature of the water 58 in the container 34 or the chemical temperature of the chemical discharge pipe 52 falls below a predetermined temperature. When the temperature rises above the set temperature, the power supply 56 of the electric heaters 24a and 24b may be cut off.

It is preferred that the inline heater also automatically controls the amount of water in the vessel. To this end, the in-line heater according to the present invention provides the electromagnetic valve 40 in the water supply pipe 38, and the water level sensor 48 immersed in the water 58 in the container 34, the control unit 60 is According to the input value of the water level sensor 48, when the water level is lowered below the predetermined level (L2) to open the electronic valve 40 of the water supply pipe 38 to replenish the water, the water level is above the predetermined level (L1) When up, close the electronic valve 40 of the water supply pipe 38 to block the water, when the water level is lowered below a certain level (L3) to generate a constant warning sound, when the water level is lowered below a certain level (L4) The power source 56 may be shut off.

In order to detect leaks from the medicine tube 12, it is preferable to further include a chemical leak detection sensor 47 in the container. The chemical leak detection sensor 47 may use a pH meter or an electrical conductivity sensor. The controller 60 may be configured to block the power supply 56 according to an input value from the drug leakage detection sensor 47.

2 and 3, the present invention prevents the water 58 contained in the vessel 34 from scattering to the outside, and supports the heat transfer heaters 24a and 24b, the stirring means 26, and the like. The cover 18 is provided.

In the inline heater according to the present invention, as shown in Figure 3, the medicine tube roll (10a, 10b), the cover 18, the heat transfer heater (24a, 24b), stirring means 26, etc. in the container 34 After combining the other peripheral devices such as the temperature sensor 46a, the water level sensor 48, the power supply 56 shown in Figure 1, installed in the etching equipment or cleaning equipment to heat the medicine in real time and then these equipment Will be used to supply

Referring to Figure 1 describes the operation of the inline heater according to the present invention.

First, the electromagnetic valve 40 of the water supply pipe is operated to fill the replenishment water to the level of L1. Next, while stirring the water by operating the stirring means 26, the temperature is raised to the desired temperature by using the heat transfer heaters 24 and 24b and the temperature sensor 46a. When the temperature of the water reaches a certain temperature, the chemicals in the chemical tank are transferred to the chemical pipe 12 in the container 34 by adjusting the desired amount using the pump 54 and a flow meter (not shown), and the remaining chemicals are transferred to the chemical tank. Circulate At this time, if the flow rate of the chemical is adjusted, the heat medium 58 exchanges heat with the chemical passing through the chemical pipe 12 so that the temperature of the chemical in the chemical discharge pipe 52 is equal to the temperature of the heat medium 58 in the container 34. . The chemicals discharged to the chemical discharge pipe 52 are returned to the chemical tank to raise the temperature of the chemical tank, or directly transferred to the etching equipment or the cleaning equipment to be used for etching or cleaning.

According to the present invention having the above-described configuration, since the corrosion of the heating wire by the chemical can be essentially blocked, not only can the life of the inline heater be extended, but also the maintenance is easy, the maintenance cost is low, and the failure of the inline heater This makes it possible to prevent the semiconductor production line from stopping. In addition, even if the amount of chemicals required by the etching or cleaning equipment fluctuates frequently, the chemicals can be heated to the required temperature within a short time. It has the effect of achieving gender and efficiency.

Claims (6)

Vessel; A liquid heat medium contained in the container; A heat transfer heater which is immersed in the heat medium to heat the heat medium; In the in-line heater for heating the semiconductor wafer wet etching and cleaning chemicals, comprising: a chemical pipe which is immersed in the heat medium to pass the semiconductor wafer etching or cleaning chemicals and heat exchanges the heat of the thermal medium to the chemicals; The vessel is provided with a temperature sensor, and a control unit for controlling the power of the heat transfer heater, and automatically connects the power to the heat transfer heater when the heat medium temperature in the vessel falls below a predetermined temperature, An inline heater for heating a semiconductor wafer wet etching and cleaning chemical, characterized in that when the temperature rises above, the power of the electric heater is automatically cut off. The method of claim 1, The chemical pipe is made of a plurality of fluorine resin tubing (細 管) in parallel, and both ends of the customs pipe is inserted and bonded to the head of the fluorine resin material through-hole formed in the flow path direction by the number of the tubing is connected to the chemical injection pipe or the chemical discharge pipe An inline heater for heating a semiconductor wafer wet etching and cleaning chemical, characterized in that. The method according to claim 1 or 2, The heat medium is water, and the container is inline heater for wet etching and cleaning chemicals heating, characterized in that the water supply pipe for replenishing the water and the overflow pipe for discharging when the water reaches a certain level. The method according to claim 1 or 2, In the container, in-line heater for heating the semiconductor wafer wet etching and cleaning chemicals, characterized in that it further comprises a heat medium stirring means for stirring or convection the heat medium so that the temperature of the heat medium is uniformly maintained at any point. The method according to claim 1 or 2, The chemical pipe is an inline heater for heating a semiconductor wafer wet etching and cleaning chemicals, characterized in that the fluorine resin material. The method of claim 5, The container further includes a chemical leak detection sensor selected from a PH meter or an electrical conductivity sensor in order to detect leakage of the medicine from the chemical pipe, and the control unit inputs from the chemical leak detection sensor. The semiconductor wafer wet etching and cleaning chemicals heating inline heater, characterized in that for automatically cutting off the power of the electric heater according to the value.

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