Semiconductor manufacturing systems

Abstract

This invention provides a semiconductor manufacturing system that promotes the reuse of materials involved in semiconductor manufacturing and reduces water usage. [Solution] The semiconductor manufacturing system 1 includes an exhaust pump 12 that reduces the pressure of exhaust gas EG1 from a first semiconductor manufacturing apparatus 11 that performs etching in a dry process by mixing it with dilution gas DG, and exhausts it as diluted exhaust gas EG2; a gas separation device 13 that separates the diluted exhaust gas EG2 into recovered gas RG containing dilution gas DG and waste gas WG1 excluding recovered gas RG; a detoxification device 14 that detoxifies the waste gas WG1; and a scrubber 15 that washes the detoxified gas with water.

Description

Technical Field

[0001] The present invention relates to a semiconductor manufacturing system for separating and reusing exhaust gas and waste liquid related to semiconductor manufacturing.

Background Art

[0002] In recent years, with the increase in the amount of information processing due to the spread of AI (Artificial Intelligence) technology, the demand for semiconductor devices has been increasing significantly. Along with this, an increase in demand for various materials such as parts, components, gases, chemicals, etc. used in semiconductor manufacturing, as well as water, electricity, etc. is expected. In order to efficiently use these resources, technologies related to the reuse of resources in semiconductor device manufacturing factories (hereinafter referred to as semiconductor manufacturing factories) have been developed.

[0003] For example, in a semiconductor manufacturing factory, since a large amount of water is used compared to ordinary households, in order to ensure the supply amount of necessary water, various technologies related to water recycling within the factory have been developed (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a semiconductor manufacturing factory, water on the order of 100,000 m per day is used, and currently about 70% of this water is covered by reuse. However, the amount of water corresponding to the remaining 30%, which is 30,000 m per day, is said to be comparable to the water supply amount for 100,000 people. When locating and constructing a semiconductor manufacturing factory, ensuring the water supply amount has become an important issue. 3 規模の水が使用されており、現状ではそのうち70%程度の水が再利用によって賄われている。しかしながら、残りの30%にあたる1日当たり3万m 3 という水量は、人口10万人分の上水道供給量に匹敵すると言われており、半導体製造工場を立地、建設するに際し、水供給量の確保は、重要な課題となっている。

[0006] Furthermore, there is a need to promote the reuse of various chemical substances used in semiconductor manufacturing processes in order to cope with the increasing consumption.

[0007] This invention has been made in view of the above circumstances, and aims to provide a semiconductor manufacturing system that promotes the reuse of materials related to semiconductor manufacturing and can reduce the amount of water used. [Means for solving the problem]

[0008] To achieve the above objective, the semiconductor manufacturing system according to this invention is: An exhaust pump that reduces the pressure of the exhaust gas from the first semiconductor manufacturing equipment, which performs etching in a dry process, by mixing it with a diluent gas, and then exhausts it as diluted exhaust gas. A gas separation device that separates the diluted exhaust gas into recovered gas containing the diluted gas and waste gas excluding the recovered gas, A detoxification device for treating the aforementioned exhaust gas, It includes a scrubber that washes the treated gas with water.

[0009] Furthermore, semiconductor manufacturing systems are A first wastewater separation device separates the wastewater from a second semiconductor manufacturing apparatus that performs etching in a wet process into pure water and concentrated wastewater consisting of used chemicals and other wastewater. A second wastewater separation device that receives the wastewater from the scrubber and the concentrated wastewater and separates it into detoxification treatment water with a fluoride ion concentration of 1000 mg / L or more and regeneration treatment water with a fluoride ion concentration of less than 1000 mg / L, A regeneration treatment apparatus that discharges the aforementioned regeneration treatment water as regeneration treatment water, The system includes a detoxification treatment device that detoxifies the aforementioned detoxification treatment water and discharges it to the outside, It would be acceptable to do so.

[0010] Furthermore, the gas separation device is It includes a multi-stage sorting unit for sequentially separating different types of the recovered gases, It may also be the case.

[0011] Further, the semiconductor manufacturing system includes an analyzer that analyzes the concentration of each of the recovered gases contained in the diluted exhaust gas flowing into the gas separation device, and a controller that controls the flow rate for each separation stage of the diluted exhaust gas based on the analysis result of the analyzer. It may also be the case.

[0012] Further, at least any one of the gas separation device, the first drainage separation device, and the second drainage separation device performs separation using membrane separation. It may also be the case.

[0013] Further, at least any one of the gas separation device, the first drainage separation device, and the second drainage separation device separates fluorine compounds. It may also be the case.

Advantages of the Invention

[0014] According to the semiconductor manufacturing system of the present invention, the gas flowing into the scrubber is separated in advance, and the recovered gas containing the dilution gas is recovered. Therefore, the reuse of the semiconductor material contained in the recovered gas is promoted, and the gas processed in the scrubber is reduced, and the amount of water used for washing can be reduced.

Brief Description of the Drawings

[0015] [Figure 1] It is a block diagram showing the configuration of a semiconductor manufacturing system according to Embodiment 1 of the present invention. [Figure 2] It is a block diagram showing the configuration of a gas separation device, an analyzer, and a controller according to Embodiment 1. [Figure 3] It is a diagram showing an example of a gas and water discharge amount simulation according to Embodiment 1. [Figure 4] It is a block diagram showing the configuration of a semiconductor manufacturing system according to Embodiment 2 of the present invention. [Figure 5]It is a diagram showing an example of the water discharge amount simulation according to Embodiment 2.

Embodiments for Carrying Out the Invention

[0016] Hereinafter, a semiconductor manufacturing system according to an embodiment of the present invention will be described with reference to the drawings.

[0017] (Embodiment 1) As shown in FIG. 1, the semiconductor manufacturing system 1 according to the present embodiment includes a first semiconductor manufacturing apparatus 11, an exhaust pump 12, a gas separation apparatus 13, a decontamination apparatus 14, a scrubber 15, and a waste water treatment apparatus 16.

[0018] The first semiconductor manufacturing apparatus 11 is an apparatus that manufactures semiconductor devices such as thin film transistors and solar cells by performing etching through a dry process. Process gases, cleaning gases, etc. used in processes such as semiconductor film formation and dry etching are supplied as supply gas SG to the first semiconductor manufacturing apparatus 11. The supply gas SG contains Ar, He, H2, NF3, HF, etc. as materials related to semiconductor manufacturing.

[0019] The exhaust pump 12 sucks the diluted exhaust gas EG2 that has been depressurized by mixing the exhaust gas EG1 discharged from the first semiconductor manufacturing apparatus 11 with the dilution gas DG, and sends it to the gas separation apparatus 13. The exhaust pump 12 is a known pump such as a dry vacuum pump or a turbo molecular pump, and is not particularly limited. By diluting the exhaust gas EG1 containing harmful components by about 100 to 1000 times in advance and depressurizing it, it can be exhausted safely without causing problems such as failures in the exhaust pump 12.

[0020] The gas separation device 13 separates the diluted exhaust gas EG2 into recovered gas RG, which is recovered and reused, and waste gas WG1, which is treated and discharged. The recovered gas RG contains the dilution gas DG. The semiconductor manufacturing system 1 can significantly reduce the amount of waste gas WG1 treated by the treatment device 14 by using the gas separation device 13 to separate and recover the dilution gas DG, which is present in large quantities in the diluted exhaust gas EG2.

[0021] Furthermore, the recovered gas RG may include valuable gases that are preferable to recover and reuse among the various components contained in the supply gas SG. As shown in Figure 2, the gas separation device 13 according to this embodiment is a multi-stage separation unit for sequentially separating different types of recovered gases. Specifically, the gas separation device 13 includes a first gas separation unit 13-1 that separates the diluted exhaust gas EG2 into a gas mainly containing nitrogen trifluoride (NF3) and a gas mainly containing argon (Ar) and nitrogen (N2), a second gas separation unit 13-2 that separates and recovers Ar and N2, and a third gas separation unit 13-3 that separates NF3 and waste gas WG1 and recovers NF3. The first gas separation unit 13-1, the second gas separation unit 13-2, and the third gas separation unit 13-3 are membrane separation type gas separation devices that separate using separation membranes suitable for each separation gas.

[0022] The gas separation device 13 according to this embodiment recovers NF3, Ar, and N2 as valuable gases, but is not limited to these, and the valuable gases to be recovered can be appropriately selected depending on the process gas used. For example, by separating and recovering fluorine compounds such as SF6, CF4, and HF in addition to NF3 as valuable gases, it is possible to suppress emissions into the external environment.

[0023] Furthermore, the semiconductor manufacturing system 1 according to this embodiment includes an analyzer 17 and a control unit 18, as shown in Figure 2. The analyzer 17 analyzes the concentration of each recovered gas contained in the diluted exhaust gas EG2 flowing into the gas separation device 13. The control unit 18 controls the flow rate of the diluted exhaust gas EG2 at each separation stage based on the analysis results of the analyzer 17. This allows for the control of the separation conditions for separation units 13-1 to 13-3, enabling efficient separation conditions for each target gas, thereby promoting the reuse of material gases.

[0024] The analyzer 17 shown in Figure 2 is configured to analyze the gases flowing into each of the separation units 13-1 to 13-3, but it is not limited to this. For example, the analyzer 17 may analyze the concentration of the recovered gas separated at each fractionation stage of the diluted exhaust gas EG2 flowing into the first gas separation unit 13-1.

[0025] The waste gas abatement device 14 is a device that safely processes and discharges the waste gas WG1 discharged from the gas separation device 13. The processing method of the waste gas abatement device 14 is not particularly limited. The waste gas abatement device 14 according to this embodiment is a combustion type waste gas abatement device that processes hydrogen compounds such as silane (SiH4), fluorine compounds such as ethane hexafluoride (C2F6) and sulfur hexafluoride (SF6), etc., by thermal decomposition. The waste gas WG2 after combustion treatment discharged from the waste gas abatement device 14 is sent to the scrubber 15.

[0026] The scrubber 15 is a device that cleans the waste gas WG2 discharged from the abatement device 14 and detoxifies harmful gases and powders. The scrubber 15 according to this embodiment is a wet abatement device commonly used in the semiconductor device manufacturing process, and is a device that performs cleaning using water. The scrubber 15 releases the gas that has been rendered harmless by the cleaning process into the atmosphere, and also sends the scrubber wastewater SD1 generated during the cleaning process to the wastewater treatment device 16.

[0027] The water used in the scrubber 15 accounts for a large proportion (for example, about 10% to 30%) of the water used in the semiconductor manufacturing system 1. In recent years, with the increasing complexity of semiconductor device structures and the resulting increase in the number of processes, the amount of waste liquid from the scrubber 15 has tended to increase. Therefore, by reducing this water, it is possible to significantly reduce the amount of water used in the semiconductor manufacturing system 1. In this embodiment, the amount of waste gas WG1 treated by the pollution control device 14 is reduced by separating the diluted exhaust gas EG2 using the gas separation device 13. This reduces the amount of waste gas WG2 treated by the scrubber 15 and also reduces the amount of water used for the cleaning process.

[0028] The wastewater treatment device 16 detoxifies the scrubber wastewater SD1 discharged from the scrubber 15 before discharging it into the external environment.

[0029] Figure 3 shows an example of simulation results for the amount of gas and water discharged in the semiconductor manufacturing system 1 according to this embodiment. As shown in Figure 3, in the semiconductor manufacturing system 1 according to this embodiment, valuable gases such as NF3, Ar, and N2 are recovered by separating the diluted exhaust gas EG2 using the gas separation device 13, and the amount of waste gas WG1 treated by the pollution control device 14 is reduced. In addition, the amount of waste gas WG2 treated by the scrubber 15 is reduced, and the amount of water used for cleaning is also reduced.

[0030] As described above, the semiconductor manufacturing system 1 according to this embodiment separates the gas to be processed by the scrubber 15 in advance and recovers the recovered gas including the dilution gas. This promotes the reuse of semiconductor materials contained in the recovered gas and reduces the amount of gas processed by the scrubber, thereby reducing the amount of water used for cleaning.

[0031] Furthermore, the gas separation device 13 according to this embodiment is equipped with a multi-stage separation unit for sequentially separating different types of recovered gas RG, so that reusable gases can be recovered individually and the recycling rate of material gases can be improved. In addition, by separating and recovering multiple types of gases, the amount of waste gas WG1 treated by the pollution control device 14 and scrubber 15 can be reduced, so the amount of water used in the washing process can be further reduced.

[0032] Furthermore, the gas separation device 13 according to this embodiment is equipped with an analyzer 17 that analyzes the concentration of each recovered gas contained in the diluted exhaust gas EG2, and the control unit 18 controls the flow rate of the diluted exhaust gas EG2 at each separation stage based on the analysis results of the analyzer 17. As a result, the separation conditions for separation units 13-1 to 13-3 can be controlled to achieve efficient separation conditions for each target recovered gas, thereby promoting the reuse of material gases.

[0033] Furthermore, the gas separation device 13 according to this embodiment separates gases by membrane separation. By using a membrane separation type gas separation device 13, it is possible to select and use a separation membrane with conditions suitable for the gas to be separated and recovered, making it possible to easily configure a gas separation device 13 according to the target gas. In addition, by configuring the gas separation device 13 as a multi-stage separation unit, it is possible to select a separation membrane suitable for the recovered gas for each separation device, making it possible to easily separate and recover different types of recovered gases.

[0034] (Embodiment 2) The semiconductor manufacturing system 1 according to Embodiment 1 described above includes a first semiconductor manufacturing apparatus 11 that manufactures semiconductor devices by etching using a dry process, and is configured to process the exhaust gas EG1 of the first semiconductor manufacturing apparatus 11. The semiconductor manufacturing system 2 according to this embodiment differs from Embodiment 1 in that it includes a third wastewater separation apparatus 19 for separating scrubber wastewater SD1, a second semiconductor manufacturing apparatus 21 that manufactures semiconductor devices by etching using a wet process, etc. Furthermore, the first semiconductor manufacturing apparatus 11 for the dry process and the processing mechanism for its exhaust gas EG1 are the same as in Embodiment 1, so the same reference numerals are used and detailed explanations are omitted.

[0035] As shown in Figure 4, the semiconductor manufacturing system 2 according to this embodiment includes a first semiconductor manufacturing apparatus 11 for the dry process, an exhaust pump 12, a gas separator 13, a pollution control device 14, a scrubber 15, and a third wastewater separator 19. The third wastewater separator 19 processes the scrubber wastewater SD1 discharged from the scrubber 15, then discharges it into the external environment, and also discharges the remaining scrubber wastewater SD2. The scrubber wastewater SD2 is processed together with the wastewater from the wet process.

[0036] Furthermore, the semiconductor manufacturing system 2 includes a second semiconductor manufacturing apparatus 21 for wet processes, a first wastewater separation apparatus 22, a second wastewater separation apparatus 23, a detoxification apparatus 24, and a regeneration apparatus 25.

[0037] The second semiconductor manufacturing apparatus 21 is a device that manufactures semiconductor devices such as thin-film transistors and solar cells by etching using a wet process. Materials such as etching solutions including sulfuric acid (H2SO4), hydrogen peroxide (H2O2), hydrofluoric acid (HF), and IPA (isopropyl alcohol), as well as pure water used for rinsing, are introduced into the second semiconductor manufacturing apparatus 21, and waste liquid WL is discharged from it.

[0038] The first wastewater separation device 22 is a device for separating and reusing waste liquid WL discharged from the second semiconductor manufacturing apparatus 21. Specifically, the first wastewater separation device 22 separates the waste liquid WL into pure water PW, used chemical solution CS, and other concentrated wastewater DL.

[0039] Pure water PW is rinse water mainly used for cleaning semiconductors in the second semiconductor manufacturing apparatus 21. After being separated and recovered in the first wastewater separation apparatus 22, it is reused in the second semiconductor manufacturing apparatus 21. Used chemical solution CS consists of various chemicals used in the second semiconductor manufacturing apparatus 21, including, for example, sulfuric acid, hydrogen peroxide, hydrofluoric acid, ammonium fluoride, phosphoric acid, IPA, as well as resist developer components, resist stripper components, etc., either individually or in mixtures. Used chemical solution CS is a very concentrated waste liquid that is transported away from the semiconductor manufacturing system 2 without treatment or reuse. After being transported away from the semiconductor manufacturing system 2, used chemical solution CS is reused for other purposes or disposed of as waste. Concentrated wastewater DL consists of waste liquids other than pure water PW and used chemical solution CS, and includes waste that is recycled and reused, and waste that is detoxified and discharged.

[0040] The method for separating waste liquid WL in the first wastewater separation device 22 is not particularly limited, but the first wastewater separation device 22 according to this embodiment separates by membrane separation. In addition, the first wastewater separation device 22 may separate and recover fluorine compounds such as hydrofluoric acid and ammonium fluoride. This can suppress the discharge of fluorine compounds into the environment and reduce the impact on the environment.

[0041] The second wastewater separation device 23 receives scrubber wastewater SD2 separated by the third wastewater separation device 19 related to the dry process and concentrated wastewater DL discharged from the first wastewater separation device 22, and separates them into detoxification treatment water DW and regeneration treatment water RW. Regeneration treatment water RW is wastewater that can be reused as water for semiconductor manufacturing systems without further treatment or with relatively easy treatment, for example, wastewater with a fluoride ion concentration of less than 1000 mg / L. Detoxification treatment water DW is wastewater that is difficult to reuse as water for semiconductor manufacturing systems with relatively easy treatment, for example, wastewater with a fluoride ion concentration of 1000 mg / L or more. In addition, the second wastewater separation device 23 may separate and recover fluorine compounds such as hydrofluoric acid and ammonium fluoride. This can suppress the discharge of fluorine compounds to the outside and reduce the impact on the environment.

[0042] The detoxification treatment device 24 is a device for detoxifying the detoxification treatment water DW discharged from the second wastewater separation device 23 and then discharging it.

[0043] The regeneration treatment device 25 regenerates the regeneration water RW discharged from the second wastewater separation device 23. The regenerated water (regenerated treated water) is reused in the semiconductor manufacturing system 2 together with the pure water PW discharged from the first wastewater separation device 22.

[0044] Figure 5 shows an example of simulation results for the amount of water supplied and discharged in the semiconductor manufacturing system 2 according to this embodiment. As shown in Figure 5, the semiconductor manufacturing system 2 according to this embodiment, like the semiconductor manufacturing system 1 according to Embodiment 1, promotes the reuse of semiconductor materials through separation and reduces the supply water and wastewater of the scrubber 15. Furthermore, by using the first wastewater separation device 22, the second wastewater separation device 23, and the regeneration treatment device 25, the reuse of semiconductor materials can be further promoted and the amount of water reused can be significantly increased. Accordingly, it is possible to reduce the amount of water discharged and thus reduce discharge costs, as well as reduce the amount of water supplied to the semiconductor manufacturing system 2.

[0045] As described above, the semiconductor manufacturing system 2 according to this embodiment separates wastewater from the wet process in addition to the dry process, which is the same as in the semiconductor manufacturing system 1 according to Embodiment 1, using the first wastewater separation device 22, the second wastewater separation device 23, and the regeneration device 25. This increases the water recycling rate of the entire system and reduces the amount of water used.

[0046] Furthermore, in the semiconductor manufacturing system 2 according to this embodiment, fluorine compounds are separated and recovered in the gas separation device 13, the first wastewater separation device 22, and the second wastewater separation device 23. This suppresses the discharge of fluorine compounds into the environment and reduces the impact on the environment. [Industrial applicability]

[0047] The present invention is suitable for semiconductor manufacturing systems that include semiconductor manufacturing equipment that performs etching by a dry process. In particular, it is suitable for semiconductor manufacturing systems that also include semiconductor manufacturing equipment that performs etching by a wet process. [Explanation of symbols]

[0048] 1,2 Semiconductor manufacturing system, 11 First semiconductor manufacturing equipment, 12 Exhaust pump, 13 Gas separation equipment, 14 Pollution removal equipment, 15 Scrubber, 16 Wastewater treatment equipment, 17 Analytical equipment, 18 Control unit, 19 Third wastewater separation equipment, 21 Second semiconductor manufacturing equipment, 22 First wastewater separation equipment, 23 Second wastewater separation equipment, 24 Detoxification equipment, 25 Regeneration equipment

Claims

1. An exhaust pump that reduces the pressure of the exhaust gas from the first semiconductor manufacturing equipment, which performs etching in a dry process, by mixing it with a diluent gas, and then exhausts it as diluted exhaust gas. A gas separation device that separates the diluted exhaust gas into recovered gas containing the diluted gas and waste gas excluding the recovered gas, A detoxification device for treating the aforementioned exhaust gas, The system includes a scrubber that washes the treated gas with water, A semiconductor manufacturing system characterized by the following features.

2. A first wastewater separation device separates the wastewater from a second semiconductor manufacturing apparatus that performs etching in a wet process into pure water and concentrated wastewater consisting of used chemicals and other wastewater. A second wastewater separation device that receives the wastewater from the scrubber and the concentrated wastewater and separates it into detoxification treatment water with a fluoride ion concentration of 1000 mg / L or more and regeneration treatment water with a fluoride ion concentration of less than 1000 mg / L, A regeneration treatment apparatus that discharges the aforementioned regeneration treatment water as regeneration treatment water, The system includes a detoxification treatment device that detoxifies the aforementioned detoxification treatment water and discharges it to the outside, The semiconductor manufacturing system according to feature 1.

3. The gas separation device is It includes a multi-stage sorting unit for sequentially separating different types of the recovered gases, A semiconductor manufacturing system according to claim 1 or 2, characterized by the above.

4. An analytical device for analyzing the concentration of each recovered gas contained in the diluted exhaust gas flowing into the gas separation device, The system includes a control unit that controls the flow rate of each separation stage of the diluted exhaust gas based on the analysis results of the analytical device, The semiconductor manufacturing system according to claim 3.

5. At least one of the gas separation device, the first wastewater separation device, and the second wastewater separation device performs separation using membrane separation. The semiconductor manufacturing system according to claim 2, characterized by the features described above.

6. At least one of the gas separation device, the first wastewater separation device, and the second wastewater separation device separates fluorine compounds. The semiconductor manufacturing system according to claim 2, characterized by the features described above.

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