Temperature measurement and static elimination structure using silicon carbide

Abstract

Provided is a temperature measurement and anti-static structure using silicon carbide, said structure being capable of instantaneously measuring the temperature of a corrosive liquid and comprising an anti-static structure. The invention has a structure that brings a silicon carbide material impregnated with carbon into direct contact with a chemical solution in a semiconductor manufacturing device, said chemical solution flowing through corrosion-resistant piping for transporting the chemical solution, so as to measure the chemical solution temperature using a change in the resistance value of the silicon carbide material, and eliminates static by means of the silicon carbide material such that the chemical solution and the corrosion-resistant piping do not acquire a charge.

Description

Temperature measurement and static elimination structure using silicon carbide

[0001] The present invention relates to a temperature measurement and static elimination structure using silicon carbide, and more particularly to a temperature measurement and static elimination structure for corrosive liquids.

[0002] For example, Patent Document 1 discloses a fluid temperature measuring device shown in Fig. 9 as a device for measuring the temperature of a liquid in a pipe through which a corrosive liquid, such as ultrapure water used for cleaning semiconductors in a semiconductor manufacturing process, flows. In Fig. 9, a T-shaped pipe 51 made of a fluororesin that is corrosion-resistant against corrosive liquids is used, and a thermometer 52 is used in which a temperature detection element 54 is embedded in a protective rod 53 also made of a fluororesin that is corrosion-resistant against corrosive liquids. The protective rod 53 is inserted into a central pipe portion 56 of the T-shaped pipe 51 that protrudes from the center of a main pipe 55, and the tip portion containing the temperature detection element 54 is immersed in the corrosive liquid flowing through the main pipe 55. The central pipe portion 56 is then tightened with a nut 57, tightly sealing the outer circumferential surface of the protective rod 53 against the inner circumferential surface of the central pipe portion 56.

[0003] However, in the fluid temperature measuring device shown in FIG. 9, the temperature detecting element 54 is protected by the protective rod 53, so the response time for temperature measurement is long and the response is poor.

[0004] 10, Patent Document 2 discloses a temperature sensor for use in an environment where corrosive gases such as sulfide gas, acid gas, and nitrogen oxide gas are present, the temperature sensor having a thermistor 61 whose resistance value changes with temperature, sealed electrodes 62 electrically connected to both sides of the thermistor 61, a glass tube 63 covering the thermistor 61 and the sealed electrode 62, and a lead wire 64 connected to the sealed electrode 62, with a viscoelastic silicone elastomer coating 65 covering the connection between the sealed electrode 62 and the lead wire 64. However, because the thermistor 61 is protected by the glass tube 63 and the silicone elastomer coating 65, the temperature sensor shown in FIG. 10 has poor responsiveness, similar to that of Patent Document 1.

[0005] Furthermore, Patent Document 3 discloses a temperature measurement device using a radiometer as a device for performing non-contact temperature measurement. However, this temperature measurement device has a problem in that it cannot obtain accurate measurement results when the emissivity of the measurement object varies or is unknown.

[0006] When chemicals in semiconductor manufacturing equipment flow through corrosion-resistant piping, static charges are generated due to friction between the chemicals and the inner surface of the piping, and the piping may become charged with static charges. In particular, when the corrosion-resistant piping is made of fluororesin, the volume resistivity of the fluororesin is 10 １８ Because the resistance is very high, at over Ω cm, it easily becomes charged. As a result, the accumulation of static charge can cause electrostatic discharge, which can damage the piping. Therefore, it is extremely important to prevent the corrosion-resistant piping through which chemicals flow in semiconductor manufacturing equipment from becoming charged.

[0007] One possible solution is to mold a fluororesin tube containing a conductive material such as carbon black or iron powder into a tube, thereby making the fluororesin tube conductive. However, because the conductive material is black, the tube also becomes opaque, which can lead to the problem that if a fluid becomes clogged inside the tube, it is difficult to determine where the clog is.

[0008] To address these problems, for example, Patent Document 4 proposes a tube having a conductive portion made of a polytetrafluoroethylene composition containing a conductive substance and a transparent portion made of polytetrafluoroethylene alone, both of which extend in the longitudinal direction of the tube. Patent Document 5 proposes a fluororesin tube in which a striped conductive portion made of a fluororesin composition containing a conductive substance and extending in the longitudinal direction of the tube is embedded in the thick wall of the transparent fluororesin tube. Also used are carbon-containing nylon or polyethylene tubes cut into a spiral shape, and transparent fluororesin tubes wrapped around a conductive member such as a stainless steel coil. All of these antistatic fluororesin tubes have a conductive portion and a transparent fluororesin portion, and are configured to provide conductivity while allowing the interior of the tube to be seen.

[0009] However, the antistatic fluororesin tube described in Patent Document 4 has a problem in that the conductive material is exposed on the inner wall, which contaminates objects passing through the tube. The antistatic resin tube described in Patent Document 5 does not have the risk of contaminating objects passing through, but the conductive portion is embedded in the thick wall portion of the tube, so the antistatic performance is insufficient.

[0010] These antistatic fluororesin tubes are obtained by simultaneously extruding a molding material for the conductive portion, which contains a conductive substance, and a molding material for the transparent portion, which consists solely of a fluororesin, into a tubular shape. However, because the molding material for the conductive portion contains a conductive substance and has a higher thermal conductivity and a faster cooling rate, this molding process can result in a phenomenon known as "sink marks," in which the wall thickness of the transparent portion in contact with the conductive portion becomes thinner. Furthermore, differences in the shrinkage rates between the conductive portion and the transparent portion during cooling can cause deformation of the tube's outer diameter and differences in wall thickness, making it difficult to mold a tube with good dimensional accuracy. In the antistatic fluororesin tube described in Patent Document 4, the conductive portion and the transparent portion have the same thickness. Similarly, in the antistatic resin tube described in Patent Document 5, the conductive portion is embedded so as to occupy a significant portion of the transparent portion, and both conductive portions are formed thick, making sink marks and deformation more pronounced.

[0011] Deformation of the tube adversely affects the sealing performance with the joint, making it easier for the passing material to leak. In particular, if the passing material is a flammable fluid, the leaked flammable gas will fill the room, and if the outer surface of the anti-static fluororesin tube is charged, sparks may fly and an explosion may occur if a worker touches the tube.

[0012] On the other hand, antistatic fluororesin tubes wound with a conductive material require complicated winding and fixing operations during production, which poses the problem of significantly increasing costs.

[0013] Japanese Patent Application Laid-Open No. 2012-47662 Japanese Patent Application Laid-Open No. 2005-221430 Japanese Patent Application Laid-Open No. 62-153720 Japanese Utility Model Application Laid-Open No. 1-96593 Japanese Patent Application Laid-Open No. 2000-266247

[0014] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a temperature measurement and static elimination structure using silicon carbide that does not have the drawbacks of the prior art as described above, can instantaneously measure the temperature of a corrosive liquid, and has the function of eliminating static electricity charged to the flow path and fluid.

[0015] Silicon carbide is a compound of carbon and silicon in a 1:1 ratio, and is extremely hard (13 on the new Mohs hardness scale), chemically stable, and resistant to hot hydrofluoric acid, nitric acid, sulfuric acid, and sodium hydroxide. It also has excellent oxidation resistance (it reacts with oxygen to form silicon dioxide (SiO ２ A dense film of SiO2 forms a protective film that covers the surface of the SiC, and the thermal expansion coefficient is low (4.5 × 10 －６ / °C), excellent heat resistance (decomposition temperature 2450°C), high thermal conductivity (100 to 350 W / m·K), and semi-conductivity.

[0016] In recent years, silicon carbide has been attracting attention as a material for power semiconductor devices, taking advantage of its semiconducting properties. The basic operating principle is the same as that of semiconductor devices such as memory, microcomputers, and ICs, but power semiconductor devices must be able to withstand higher voltages and control larger currents than memory and other devices. For this reason, they must have requirements such as a large band gap and high dielectric breakdown strength.

[0017] As shown in Table 1 below, 4H-SiC (a type of silicon carbide) meets the requirements for a power semiconductor device material. 4H-SiC has a higher dielectric breakdown strength than Si, which allows it to be miniaturized, reducing power loss, and its wide bandgap allows it to operate at high temperatures and be used under harsh conditions.

[0018]

[0019] In Table 1, 4H-SiC is an example of a silicon carbide crystal. There are many crystal systems of silicon carbide (currently 215 types have been discovered), and their crystal structure is as shown in Figure 1. As shown in Figure 1(a), if an equilateral triangle is scored and folded up and the adjacent edges are glued together, a regular tetrahedron with four equilateral triangles as its surface is created. A silicon carbide crystal can be assembled from this regular tetrahedron, with Si or C atoms at the four vertices and a C or Si atom at the center of gravity. In diamond, all of the vertices and center of gravity are C atoms, while in silicon, all of the vertices and center of gravity are Si atoms. This structure gives silicon carbide its properties, which are intermediate between those of diamond and silicon.

[0020] When the above tetrahedra are densely arranged on a plane, a mesh pattern is formed as shown in Figure 1(b). The three-legged black circles at 120° intervals in the center of the equilateral triangle represent the atoms at the vertices of the tetrahedron, and the other black circles represent the atoms at the base of the tetrahedron. In this way, a layer of dense tetrahedrons is created. The tetrahedra of the second layer, which sits on top of the first layer, are arranged using the vertices of the first layer, i.e., the three-legged black circles, as scaffolds. In this case, there are two possible arrangements: (<) and (>), which are indicated by the diagonal lines at the right end of Figure 1(b). These (<) and (>) patterns create many crystalline polymorphs in silicon carbide.

[0021] The second layer is arranged in either a (<) or (>) equilateral triangle with a diagonal line. The vertex of the second layer is the center of the diagonal equilateral triangle, that is, the white circle surrounding the (<) symbol or the (>) symbol in Figure 1(b), and this becomes the scaffolding for stacking the third layer.

[0022] The atoms on the bottom of the first layer are located directly below the white circle surrounding the (>) symbol in Figure 1(b). That is, if the first layer, oriented (<), is stacked on top of the second layer, oriented (>), and then the third layer, oriented (<), is stacked on top of that, in the order (<)(>)(<)(>)(<)(>)..., the atoms rise in a zigzag pattern, and two layers form one period. This crystal has hexagonal symmetry, so it is referred to as 2H. Also, since there is one (<) and one (>), it is referred to as zigzag 11. Furthermore, if three layers form one period when stacked (<)(<)(<)(<)..., it has cubic symmetry, so it is referred to as 3C. Table 2 below lists several silicon carbide crystal systems with shorter repeat periods.

[0023]

[0024] In Table 2, the "(32)3" in the 15R zigzag indicates that one cycle is formed by repeating three times the sequence (<) (<) (<) (>) (>). The R indicates the symmetry of a rhombohedral crystal surrounded by six diamonds. Silicon carbide has many crystal systems, but the only difference is the orientation of the (<) or (>) when the same crystal layers are stacked. The interatomic distance between adjacent Si-C atoms is the same regardless of the crystal system, and the density is also the same in all crystal systems. Industrially, silicon carbide is produced by placing a layer of graphite powder between graphite electrodes on the left and right ends, with layers of silica powder and coke above and below the graphite powder layer. When a voltage is applied to the electrodes on the left and right ends, the graphite powder generates heat, heating the surrounding raw materials. As a result, fine 3C atoms begin to form above 1500°C, and as the temperature rises, the 3C atoms disappear, and 4H, 6H, etc. are formed. This reaction produces SiO ２ +3C→SiC+2CO As the silicon carbide of the present invention, the silicon carbides listed in Table 2 can be used, but are not limited thereto.

[0025] As described above, the present invention is characterized by the use of silicon carbide, which has attracted attention as a material for power semiconductor devices. The gist of the present invention is that "a silicon carbide material impregnated with carbon comes into direct contact with a chemical liquid flowing through a corrosion-resistant pipe for transporting the chemical liquid in a semiconductor manufacturing device, and the temperature of the chemical liquid is measured by measuring the change in the resistance value of the silicon carbide material, and the silicon carbide material is used to neutralize the chemical liquid and the corrosion-resistant pipe so that they do not become charged."

[0026] The present invention has the extremely important feature of not only being able to measure the temperature of the chemical solution by detecting changes in the resistance value of the silicon carbide material, but also being able to remove static electricity from the chemical solution and corrosion-resistant piping that come into contact with the silicon carbide material.

[0027] FIGS. 1(a) and 1(b) are schematic diagrams illustrating the crystal structure of silicon carbide. FIG. 2 is a diagram illustrating the configuration of essential parts of one embodiment of a semiconductor manufacturing apparatus to which the present invention can be applied. FIG. 3 is a diagram illustrating the configuration of essential parts of another embodiment of a semiconductor manufacturing apparatus to which the present invention can be applied. FIG. 4 is a diagram illustrating an embodiment in which a silicon carbide round rod can be used as a temperature sensor and a static eliminator for a semiconductor manufacturing apparatus. FIG. 5 is a diagram illustrating another embodiment in which a silicon carbide round rod can be used as a temperature sensor and a static eliminator for a semiconductor manufacturing apparatus. FIG. 6 is a cross-sectional view illustrating an embodiment in which a silicon carbide round rod is disposed in a flow path through which a fluid such as a chemical solution used in a semiconductor manufacturing apparatus flows. FIG. 7 is a diagram illustrating the results of fluid temperature measurement performed by disposing a silicon carbide round rod in a flow path through which a fluid such as a chemical solution flows in the semiconductor manufacturing apparatus shown in FIG. 4. FIG. 8 is a diagram illustrating another result of fluid temperature measurement performed by disposing a silicon carbide round rod in a flow path through which a fluid such as a chemical solution flows in the semiconductor manufacturing apparatus shown in FIG. 4. FIG. 9 is a longitudinal cross-sectional view of a fluid temperature measurement device described in Patent Document 1. FIG. 10 is a cross-sectional view of the thermistor described in Patent Document 2.

[0028] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings, in which a cleaning process and a rinsing process for a semiconductor wafer are described.

[0029] FIG. 2 is a diagram showing the configuration of the main parts of one embodiment of a semiconductor manufacturing apparatus to which the present invention can be applied.

[0030] The semiconductor cleaning apparatus 1 includes a processing tank 3 for cleaning and rinsing semiconductor wafers 2, a particle monitor 6 provided in a bypass pipe of the first drain pipe 4 as a particle number measuring means for measuring the number of particles in the processing liquid used for rinsing, a resistivity measuring instrument 7 provided in the second drain pipe 5 as a resistivity measuring means for measuring the resistivity of the processing liquid used for rinsing, and a control unit 8 as a control means for determining the end point of the rinsing process based on the measurement results of the particle monitor 6 and the resistivity measured by the resistivity measuring instrument 7 and terminating the rinsing process in the processing tank 3. Here, cleaning processes include processes such as resist stripping, processes for removing particles and metal impurities using alkali or acid treatment, and processes for etching away films formed on wafers. The first drain pipe 4 and the second drain pipe 5 are made of polytetrafluoroethylene (PTFE), but perfluoroalkoxyalkane (PFA), for example, can also be used. In other words, a fluororesin having chemical resistance can be used.

[0031] In this semiconductor cleaning apparatus 1, semiconductor wafers 2 are immersed in a processing liquid stored in a processing tank 3 and cleaned with a cleaning liquid (chemicals) such as SC1, followed by a rinsing process with ultrapure water (UPW), and the processing liquid is successively overflowed from the processing tank 3 and discharged through a first drain pipe 4 and a second drain pipe 5. When performing the cleaning process, valves are opened to supply the cleaning liquid, ultrapure water, ozonated ultrapure water (ozonated UPW), and heated ultrapure water (hot UPW) to the processing tank 3. When performing the rinsing process, valves are opened and closed to supply only ultrapure water to the processing tank 3.

[0032] Furthermore, the control unit 8 that controls the rinsing process as described above is configured to determine that the desired rinsing process has been completed when the number of particles measured by the particle monitor 6 becomes equal to or less than a predetermined value and the resistivity measured by the resistivity measuring instrument 7 becomes equal to or greater than a predetermined value.

[0033] Next, a semiconductor cleaning method using the semiconductor cleaning apparatus 1 will be described.

[0034] First, for cleaning, the semiconductor wafer 2 is immersed in the processing solution in the processing tank 3. Next, the valves of the semiconductor cleaning device 1 are opened to supply the cleaning chemical solution, ultrapure water, ozonated ultrapure water, and heated ultrapure water to the processing tank 3.

[0035] After the predetermined cleaning process is performed, a rinse process for removing the cleaning chemicals is started, and the valve is opened and closed to supply only ultrapure water to the processing tank 3, while the processing liquid is allowed to overflow from the processing tank 3 successively.

[0036] Next, the particle monitor 6 measures the number of particles in the processing liquid that has been rinsed, and the resistivity measuring instrument 7 measures the resistivity of the processing liquid that has been rinsed.

[0037] Next, the control unit 8 compares the measured particle count and resistivity with predetermined values, respectively, to determine the end point at which the rinsing process is completed. That is, in this step, the control unit 8 determines that the desired rinsing process is completed when the particle count is equal to or less than a predetermined value and the resistivity is equal to or greater than a predetermined value. On the other hand, if the particle count is greater than a predetermined value or the resistivity is lower than a predetermined value, the control unit 8 determines that the desired rinsing process is not completed, and the process returns to the step described in paragraph 0036 to continue measuring the particle count and resistivity.

[0038] Next, when the control unit 8 determines in step 5 that the rinsing process is complete, it becomes possible to request wafer transport, and the wafer is transported from the processing bath to a dryer and dried. Then, the process proceeds to the next step. This completes the semiconductor cleaning process by the semiconductor cleaning apparatus 1.

[0039] 3 is a diagram showing the essential components of another embodiment of a semiconductor cleaning apparatus to which the present invention can be applied. In this embodiment, particle monitor 6 additionally measures the number of particles in a highly clean processing solution before cleaning semiconductor wafers 2. Semiconductor cleaning apparatus 1 further includes a calculation processing unit 9, which is a calculation means for calculating the difference between the number of particles in the processing solution before cleaning semiconductor wafers 2 measured by particle monitor 6 and the number of particles in the processing solution after rinsing.

[0040] Here, the control unit 8 determines the end point of the rinsing process based on the calculation result of the calculation processing unit 8 and the resistivity measured by the resistivity measuring instrument 7, and terminates the rinsing process. That is, the control unit 8 determines that the rinsing process is completed when the difference in the number of particles calculated by the calculation processing unit 9 becomes equal to or less than a predetermined value and the resistivity becomes equal to or greater than a predetermined value.

[0041] Next, a semiconductor cleaning method using the semiconductor cleaning apparatus 1 will be described.

[0042] The semiconductor cleaning method of this embodiment further includes a step of measuring the number of particles in the processing liquid before the cleaning processing of the semiconductor wafer 2 is performed.

[0043] In addition, in the step of determining the end point of the rinsing process, the control unit 8 determines the end point of the rinsing process based on the difference between the number of particles in the processing liquid before the cleaning process and the number of particles in the processing liquid after the rinsing process, and the measurement results of the resistivity. That is, in the step of determining the end point of the rinsing process, the rinsing process is determined to be completed when the difference between the number of particles in the processing liquid before the cleaning process and the number of particles in the processing liquid after the rinsing process is equal to or less than a predetermined value, and the resistivity of the processing liquid is equal to or greater than a predetermined value. On the other hand, if the difference in the number of particles is greater than the predetermined value or the resistivity is lower than the predetermined value, the control unit 8 determines that the desired rinsing process has not been completed, and returns to the step described in paragraph 0036 to continue measuring the number of particles and the resistivity.

[0044] If it is determined that the rinsing process has been completed in the step of determining the end point of the rinsing process, the rinsing process is terminated as in the above embodiment, the semiconductor wafer 2 is dried, and the process proceeds to the next step.

[0045] Next, as shown in Figure 4, 25°C water was injected into flow path 13 instead of the chemical solution and ultrapure water, and the 25°C water was discharged through the treatment tank and the first drainage pipe 4 and the second drainage pipe 5. A silicon carbide rod 10 impregnated with 5.3% carbon was placed through flow path 13 so that a portion of it came into contact with the water flowing through flow path 13 (as shown in Figure 6, which will be described later). The other ends of wires 11a and 11b connected to the upper and lower ends of silicon carbide rod 10 were connected to power source 12, and a current of 0.001 mA was passed through silicon carbide rod 10. The resistance of silicon carbide rod 10 was confirmed to be 4.2 MΩ, and the voltage between the terminals of rod 10 was confirmed to be 4.2 V. When 40°C hot water was injected into the flow path 13 instead of 25°C water, a voltage change of approximately 1 V was observed, as confirmed by an oscilloscope, as shown in Figure 7. When 90°C hot water was injected into the flow path 13 instead of 25°C water, a voltage change of approximately 3.5 V was observed, as confirmed by an oscilloscope, as shown in Figure 8. The time required to confirm the voltage change (response time) was approximately 0.2 seconds for both hot water temperatures, demonstrating that the silicon carbide round bar 10 can be used as a temperature sensor. The amount of carbon impregnation into the silicon carbide round bar 10 is preferably approximately 4.9 to 5.7%.

[0046] 5 shows another embodiment in which a silicon carbide rod can be used as a temperature sensor and a static eliminator in a semiconductor manufacturing apparatus. This semiconductor manufacturing apparatus is a single-wafer processing apparatus for processing substrates W, such as semiconductor wafers (in this embodiment, substantially circular substrates), one by one. This semiconductor manufacturing apparatus includes a spin chuck 21 that holds and rotates the substrate W substantially horizontally, a rotation drive mechanism 22 that applies rotational force to the spin chuck 21, a chemical solution nozzle 23 that supplies a chemical solution to the substrate W held and rotated by the spin chuck 21, a pure water nozzle 24 that supplies pure water to the substrate W held and rotated by the spin chuck 21, and an organic solvent nozzle 25 that supplies an organic solvent (isopropyl alcohol) to the substrate W held and rotated by the spin chuck 21.

[0047] The spin chuck 21 includes a rotation shaft 26 disposed substantially vertically and a substrate suction portion 27 coupled to the upper end of the rotation shaft 26, and holds the central region of the lower surface of the substrate W by vacuum suction. A rotational force is transmitted to the rotation shaft 26 from a rotation drive mechanism 22. The rotation drive mechanism 22 includes a motor and the like, and is controlled by a control device 28. This allows the rotation speed of the spin chuck 21 to be varied or the rotation to be stopped.

[0048] A chemical liquid is supplied to the chemical liquid nozzle 23 from a chemical liquid supply source via a chemical liquid valve 29. From the chemical liquid supply source, a chemical liquid such as an etching liquid such as hydrofluoric acid or a polymer removal liquid for removing resist residue on the surface of the substrate W is supplied to the chemical liquid nozzle 23.

[0049] Pure water from a pure water supply source is supplied to the pure water nozzle 24 via a pure water valve 30. However, instead of supplying pure water, so-called functional water may be supplied from the nozzle 24 to the surface of the substrate W. Functional water is water to which a certain function has been imparted to pure water, such as carbonated water, hydrogen water (reduced water), ozone water, and electrolytic ion water.

[0050] The organic solvent nozzle 25 is adapted to receive an organic solvent from an organic solvent supply source via an organic solvent valve 31 .

[0051] The opening and closing of the chemical valve 29, the pure water valve 30, and the organic solvent valve 31 are controlled by a control device 28.

[0052] Upstream of the chemical nozzle 23, the pure water nozzle 24, and the organic solvent nozzle 25, round rods 32a, 32b, and 32c made of silicon carbide and impregnated with 5.3% carbon are arranged so as to penetrate the flow paths through which the chemical, pure water, and organic solvent flow, respectively (as shown in FIG. 6), so that parts of the rods come into contact with the chemical, pure water, and organic solvent flowing through the respective flow paths.

[0053] In Fig. 6, 41 denotes a hollow pipe made of PTFE through which a chemical solution, pure water, or an organic solvent flows in the direction indicated by the arrow, and a round rod 42 made of silicon carbide is disposed so as to pass through the hollow pipe 41. 43a and 43b are O-rings for sealing the round rod 42.

[0054] In a semiconductor manufacturing apparatus configured as shown in FIG. 5 , when silicon carbide round rods 32 a, 32 b, and 32 c impregnated with 5.3% carbon are not positioned upstream of chemical nozzle 23, pure water nozzle 24, and organic solvent nozzle 25, substrate W is attracted by substrate suction section 27, and control device 28 controls rotation drive mechanism 22 to rotate substrate W at a predetermined rotation speed while chemical nozzle 23, pure water nozzle 24, and organic solvent nozzle 25 eject chemical, pure water, or organic solvent toward substrate W. Friction between the chemical, pure water, or organic solvent and the PTFE hollow piping causes high-voltage static electricity to build up in the PTFE hollow piping and the chemical, pure water, or organic solvent. As a result, the moment the chemical, pure water, or organic solvent ejected from chemical nozzle 23, pure water nozzle 24, and organic solvent nozzle 25 comes into contact with substrate W, electrostatic breakdown occurs in the semiconductor electrical circuits on substrate W. At this time, when the static electricity was measured near the chemical nozzle 23 using a static electricity measuring instrument manufactured by Shishido Electrostatic Corporation under the trade name "Statiron Dz4", it was found to be 16,000 volts.

[0055] 5, silicon carbide round rods 32a, 32b, and 32c impregnated with 5.3% carbon were positioned upstream of chemical nozzle 23, pure water nozzle 24, and organic solvent nozzle 25. Then, substrate W was attracted by substrate suction unit 27, and control device 28 controlled rotation of substrate W at a predetermined rotation speed by rotation drive mechanism 22. Chemical, pure water, or organic solvent was ejected toward substrate W from chemical nozzle 23, pure water nozzle 24, and organic solvent nozzle 25, without electrostatic breakdown of the semiconductor electrical circuit on substrate W. At this time, static electricity was measured near chemical nozzle 23 using a static electricity meter with the trade name "Statiron Dz4" manufactured by Shishido Electrostatic Corporation, and was found to be 80 volts. That is, high-voltage static electricity generated by friction between the chemical, pure water, or organic solvent and the PTFE hollow piping likely flowed to silicon carbide round rods 32a, 32b, and 32c.

[0056] The temperature measurement and anti-static structure of the present invention is particularly useful as a temperature measurement and static removal structure for chemical liquids used in semiconductor manufacturing equipment in corrosion-resistant piping through which the chemical liquids flow.

[0057] REFERENCE SIGNS LIST 1 Semiconductor manufacturing equipment 2 Semiconductor wafer 3 Processing tank 4 First drain pipe 5 Second drain pipe 6 Particle monitor 7 Resistivity measuring instrument 8 Control unit 9 Arithmetic processing unit 10 Silicon carbide round rod 11a, 11b Fixing member 12a, 12b Wiring 13 Power supply 21 Spin chuck 22 Rotation drive mechanism 23 Chemical solution nozzle 24 Pure water nozzle 25 Organic solvent nozzle 26 Rotating shaft 27 Substrate suction unit 28 Control device 29 Chemical solution valve 30 Pure water valve 31 Organic solvent valve 32a, 32b, 32c Silicon carbide round rod 41 PTFE hollow pipe 42 Silicon carbide round rod 43a, 43b O-ring

Claims

1. A temperature measurement and static elimination structure using silicon carbide, characterized in that a silicon carbide-based material impregnated with carbon is in direct contact with a chemical solution flowing through a corrosion-resistant pipe for transferring the chemical solution of a semiconductor manufacturing apparatus, and the temperature of the chemical solution is measured by a change in the resistance value of the silicon carbide-based material, and static electricity is eliminated by the silicon carbide-based material so that the chemical solution and the corrosion-resistant pipe are not charged.

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