Process chamber tail gas pipeline cleaning device and method and semiconductor process equipment

Abstract

The invention discloses a device and method for cleaning a tail gas pipeline of a process chamber and semiconductor process equipment, and the device comprises a gas supply mechanism which is configured to be communicated with the tail gas pipeline, and the gas supply mechanism is used for introducing diluent gas and first process gas into the tail gas pipeline, the first process gas reacts with a by-product deposited in the tail gas pipeline to generate a first-stage product which can be carried out of the tail gas pipeline by the diluent gas; and introducing diluent gas and second process gas into the tail gas pipeline, so that the second process gas reacts with the residual primary product in the tail gas pipeline to generate a secondary product which can be carried out of the tail gas pipeline by the diluent gas. The problem that the tail gas pipeline is blocked due to deposition of various byproducts in the tail gas pipeline of the process chamber can be solved.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor equipment, and more specifically, relates to a process chamber exhaust pipeline cleaning device, method and semiconductor process equipment. Background Art

[0002] With the development of semiconductor industry technology, chemical vapor deposition technology has been widely used to prepare single or compound semiconductor thin films, such as the preparation of Si, Ge, SiGe, SiP, InP, GaAs, GaN, SiC and other thin film devices. Chemical vapor deposition sources are commonly gaseous or liquid, with a few solid sources; liquid or solid sources are generally transported to the chamber by the saturated vapor pressure of the carrier gas. Reaction by-products are generally gaseous and solid. Improving the utilization rate of chemical vapor deposition reaction sources and reducing by-products can effectively reduce production costs. However, due to many factors such as the differences in the chemical properties of different reaction sources, process conditions, device performance requirements, and machine utilization, the source utilization rate of chemical vapor deposition technology is low; many reactant products and reaction intermediates are discharged from the chamber in the form of by-products.

[0003] like Figure 1 As shown, the conventional reaction chamber tail gas pipeline system is generally composed of a pressure controller PT, a ball valve, a pneumatic valve PV, a throttle valve M, a pump, a multi-section tail gas pipeline, etc. The reaction by-products in the process chamber are transported to the tail gas collection (adsorption) system through the machine tail gas pipeline. Relative to the chamber, the tail gas pipeline system is not heated. After the tail gas enters the tail gas pipeline, the temperature drops sharply. Some solid by-products will be deposited on the inner wall of the pipeline when they are cold. The deposition of a large amount of by-products will cause the blockage of components such as pipelines or valves, thereby affecting the normal process growth conditions of the machine, and the tail gas pipeline needs to be removed for maintenance.

[0004] Existing solutions of heating the exhaust pipe or adding a particulate filter in the exhaust pipe have limited effects, cannot completely avoid the deposition of byproducts in the pipe system, and will result in additional maintenance costs for the newly added components. Summary of the invention

[0005] The purpose of the present invention is to provide a process chamber exhaust pipeline cleaning device, method and semiconductor process equipment to solve the problem of exhaust pipeline blockage caused by the deposition of various by-products in the process chamber exhaust pipeline.

[0006] To achieve the above-mentioned purpose, the first aspect of the present invention provides a process chamber exhaust pipeline cleaning device, comprising:

[0007] An air supply mechanism, the air supply mechanism is configured to communicate with the exhaust gas pipeline, and the air supply mechanism is used to:

[0008] Introducing a dilution gas and a first process gas into the tail gas pipeline, so that the first process gas reacts with the by-products deposited in the tail gas pipeline to generate a primary product that can be carried out of the tail gas pipeline by the dilution gas;

[0009] as well as,

[0010] A dilution gas and a second process gas are introduced into the tail gas pipeline, so that the second process gas reacts with the primary product remaining in the tail gas pipeline to generate a secondary product that can be carried out of the tail gas pipeline by the dilution gas.

[0011] Optionally, one end of the tail gas pipeline is connected to the process chamber through an isolation valve, and the other end of the tail gas pipeline is connected to a tail gas collection system through an exhaust pump;

[0012] The gas supply mechanism includes a dilution gas delivery pipeline, a first process gas delivery pipeline, a second process gas delivery pipeline and a main pipeline;

[0013] One end of the dilution gas delivery pipeline is connected to the dilution gas supply end, one end of the first process gas delivery pipeline is connected to the first process gas supply end, and one end of the second process gas delivery pipeline is connected to the second process gas supply end;

[0014] The other end of the dilution gas delivery pipeline, the other end of the first process gas delivery pipeline, and the other end of the second process gas delivery pipeline are respectively connected to one end of the main pipeline;

[0015] The other end of the main pipeline is communicated with the exhaust pipeline.

[0016] Optionally, at least one switch function valve is provided on the exhaust gas pipeline;

[0017] The air supply mechanism also includes at least two branch pipelines, wherein one end of each of the at least two branch pipelines is connected to the main pipeline, and the other end of each branch pipeline is respectively connected to the exhaust gas pipeline, and one branch pipeline is connected between the isolation valve and the switching function valve, between the switching function valve and the exhaust pump, and between adjacent switching function valves.

[0018] Optionally, a first pneumatic valve and a first mass flow controller are provided on the dilution gas delivery pipeline;

[0019] A second pneumatic valve and a second mass flow controller are provided on the first process gas delivery pipeline;

[0020] A third pneumatic valve and a third mass flow controller are provided on the second process gas delivery pipeline;

[0021] Each of the branch pipelines is provided with a fourth pneumatic valve and a first manual valve.

[0022] Optionally, the by-products include silicon, silicon tetrachloride and phosphorus.

[0023] Optionally, the dilution gas includes nitrogen, the first process gas includes oxygen or compressed air, and the second process gas includes hydrogen fluoride.

[0024] Optionally, a heating mechanism is also provided on the exhaust gas pipeline.

[0025] A second aspect of the present invention provides a method for cleaning an exhaust gas pipeline, wherein the exhaust gas pipeline is cleaned using the process chamber exhaust gas pipeline cleaning device according to any one of the first aspects, and the cleaning method comprises:

[0026] A dilution gas and a first process gas are introduced into the tail gas pipeline, the first process gas and the by-products in the tail gas pipeline generate a primary product that can be carried out of the tail gas pipeline by the dilution gas, the first process gas releases heat when reacting with the by-products, and after the dilution gas and the first process gas are introduced for a first set time or when the temperature of the tail gas pipeline rises to a first set temperature, the introduction of the first process gas is stopped;

[0027] Continue to introduce the dilution gas into the tail gas pipeline, and evacuate the tail gas pipeline to discharge the first process gas remaining in the tail gas pipeline;

[0028] Controlling the temperature of the tail gas pipeline to a second set temperature, and stopping the introduction of the second process gas after introducing the dilution gas and the second process gas into the tail gas pipeline for a second set time, so that the second process gas reacts with the primary product remaining in the tail gas pipeline and generates a secondary product that can be carried out of the tail gas pipeline by the dilution gas;

[0029] Continue to introduce the dilution gas into the tail gas pipeline, and evacuate the tail gas pipeline to discharge the second process gas remaining in the tail gas pipeline;

[0030] All the above steps are executed in a cycle until the dilution gas and the first process gas are introduced into the tail gas pipeline and the temperature of the tail gas pipeline rises below the third set temperature, and then the cycle is stopped.

[0031] Optionally, an isolation valve is provided on the tail gas pipeline, and before the dilution gas and the first process gas are introduced into the tail gas pipeline, the following further comprises:

[0032] introducing the dilution gas into the process chamber and the tail gas pipeline through the chamber air inlet to replace the epitaxial process gas in the tail gas pipeline with the dilution gas and reduce the temperature of the tail gas pipeline to a fourth set temperature, wherein the fourth set temperature is lower than the first set temperature;

[0033] Shut off the chamber air intake and close the isolation valve.

[0034] Optionally, the dilution gas is nitrogen, the first process gas is oxygen, and in the step of introducing the dilution gas and the first process gas into the tail gas pipeline, a flow ratio of the first process gas to the dilution gas is in a range of 1:9-1:24;

[0035] Alternatively, the dilution gas is nitrogen, the first process gas is compressed air, and in the step of introducing the dilution gas and the first process gas into the exhaust pipeline, the flow ratio of the first process gas to the dilution gas is in the range of 1:1-1:5.

[0036] Optionally, in the step of introducing the dilution gas and the first process gas into the tail gas pipeline, the total flow of the first process gas and the dilution gas is 10%-50% of the maximum flow of the process chamber.

[0037] Optionally, the dilution gas is nitrogen, and the second process gas is hydrogen fluoride;

[0038] In the step of introducing the dilution gas and the second process gas into the tail gas pipeline, the flow ratio of the second process gas to the dilution gas is in the range of 1:10-1:50.

[0039] Optionally, the first set temperature ranges from 150-200°C; the second set temperature ranges from 100-150°C; and the third set temperature ranges from 0-10°C.

[0040] A third aspect of the present invention provides a semiconductor process equipment, comprising a process chamber, an exhaust gas pipeline connected to the process chamber, and a process chamber exhaust gas pipeline cleaning device as described in any one of the first aspects.

[0041] The beneficial effects of the present invention are:

[0042] The device of the present invention can introduce a dilution gas, a first process gas and a second process gas into the exhaust pipe of the process chamber through an additionally arranged gas supply mechanism. By introducing the dilution gas and the first process gas into the exhaust pipe, the first process gas can react with the by-products deposited in the exhaust pipe to generate a primary product that can be carried out of the exhaust pipe by the dilution gas. Then, by introducing the dilution gas and the second process gas into the exhaust pipe, the second process gas can react with the primary product remaining in the exhaust pipe to generate a secondary product that can be carried out of the exhaust pipe by the dilution gas. Through the above process, the by-products deposited in the exhaust pipe are converted into gaseous substances such as gas or smoke, which are carried out of the exhaust pipe by the dilution gas, thereby solving the problem of exhaust pipe blockage caused by the deposition of multiple by-products in the exhaust pipe in the advanced integrated circuit manufacturing, thereby reducing the maintenance frequency of the exhaust pipe, improving the utilization rate of the machine, and effectively reducing the manufacturing cost of advanced integrated circuits.

[0043] The system of the present invention has other characteristics and advantages, which will be apparent from the drawings incorporated herein and the following detailed description, or will be described in detail in the drawings incorporated herein and the following detailed description, which together serve to explain the specific principles of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, in which like reference numerals generally represent like components.

[0045] Figure 1 A schematic diagram showing a conventional exhaust gas piping system of a chemical vapor deposition device.

[0046] Figure 2 A schematic diagram of adding a heating belt to an exhaust gas pipeline system of prior art 1 is shown.

[0047] Figure 3 A schematic diagram of an exhaust gas pipeline system according to prior art 1 in which a particulate filter is added is shown.

[0048] Figure 4 A schematic diagram of a process chamber exhaust pipeline cleaning device according to Example 1 of the present invention is shown.

[0049] Figure 5 A step diagram of a method for cleaning an exhaust gas pipeline in a process chamber according to Embodiment 2 of the present invention is shown. DETAILED DESCRIPTION

[0050] Most byproducts of chemical vapor deposition are highly hazardous and difficult to handle, which leads to high safety requirements for maintenance operations of the tail gas pipeline system. Maintenance must follow strict operating standards, resulting in long maintenance operations and long recovery cycles. In advanced integrated circuit manufacturing, the preparation of SiGe, SiP and other film devices through chemical vapor deposition processes requires the use of a large amount of special gases such as phosphine, germane, silane, dichlorosilane, trichlorosilane, etc. The reaction byproducts contain a large amount of phosphorus, silicon, and silicon tetrachloride. Phosphorus and silicon are easy to agglomerate when they are cold. Silicon tetrachloride is a viscous liquid. Phosphorus, silicon, silicon tetrachloride, etc. are easily mixed and deposited in the tail gas pipeline to form a relatively viscous substance, which causes the valves, pumps, filters, etc. in the tail gas pipeline to be blocked, reducing the maintenance cycle of the tail gas pipeline. When the tail gas pipeline of the process chamber is disassembled for maintenance, phosphorus and silicon tetrachloride will react with oxygen in the air to produce a large number of toxic and harmful particles, which seriously endangers the safety of maintenance personnel on site.

[0051] Prior art 1 is to add a heating device to the tail gas pipeline to increase the temperature of the tail gas pipeline, thereby reducing the deposition of solid phosphorus and silicon, and liquid silicon tetrachloride in the tail gas pipeline system at room temperature. Figure 2 As shown in the figure, heating belts are installed on the periphery of the exhaust pipeline, and the temperature control and heating of the exhaust pipeline are realized in sections according to the heat restrictions of different parts of the exhaust pipeline, which can alleviate the condensation and deposition of some by-products (phosphorus, silicon, silicon tetrachloride) in the exhaust pipeline system. However, due to the complex structure of the components of the pipeline system and the long distance between the machine and the exhaust treatment system, the temperature control effect of different areas is greatly different through the heating belt heating method, resulting in valve blockage at key connections such as valves of the valve body and valves and pipelines.

[0052] Prior art 2 is to add or pre-install a particle filter in the exhaust pipe system. Figure 3 As shown, the compound epitaxial process generates many particles, and they are easy to condense into large particles when cooled. By adding or pre-placing a particle filter with a cooling system, a low-temperature environment is created in the filter, and the by-products are deposited in the filter in advance, reducing the deposition in key components such as valve switches and pump rotors. However, due to the condensation effect of the filter, it is impossible to completely avoid the deposition of by-products in the pipeline system. At the same time, since the filter absorbs a large amount of by-products, the maintenance and treatment process of the filter is also difficult.

[0053] The present invention provides a process chamber exhaust pipeline cleaning device, method and semiconductor process equipment to solve the problem of exhaust pipeline blockage caused by the deposition of various by-products (silicon, silicon tetrachloride, phosphorus) in the exhaust pipeline in advanced integrated circuit manufacturing, thereby reducing the maintenance frequency of the exhaust pipeline, improving the utilization rate of the machine, and effectively reducing the manufacturing cost of advanced integrated circuits.

[0054] The present invention will be described in more detail below with reference to the accompanying drawings. Although preferred embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0055] Example 1

[0056] like Figure 4 As shown, this embodiment provides a process chamber tail gas pipeline cleaning device. The process chamber 1 of this embodiment may be an epitaxial process chamber. The tail gas pipeline cleaning device of this embodiment includes:

[0057] The air supply mechanism is configured to communicate with the exhaust gas pipeline 2, and the air supply mechanism is used to:

[0058] A dilution gas and a first process gas are introduced into the exhaust pipe 2 so that the first process gas reacts with the by-products deposited in the exhaust pipe 2 to generate a primary product that can be carried out of the exhaust pipe 2 by the dilution gas; and a dilution gas and a second process gas are introduced into the exhaust pipe 2 so that the second process gas reacts with the primary product remaining in the exhaust pipe 2 to generate a secondary product that can be carried out of the exhaust pipe 2 by the dilution gas.

[0059] Taking the byproducts generated by the epitaxial process as an example, the diluent gas in the present application may include nitrogen, the first process gas may include oxygen or compressed air, and the second process gas may include hydrogen fluoride. Among them, the oxygen in the first process gas can react with the phosphorus of the byproduct species to produce phosphorus oxide (phosphorus pentoxide, phosphorus trioxide), and the reaction generates smoky phosphides while releasing heat, and the heat promotes the reaction of oxygen with silicon and silicon tetrachloride to generate substances such as silicon dioxide, so the primary product includes smoky phosphides, silicon dioxide and reaction generated gases (Cl2, etc.), and the smoky phosphides, reaction generated gases and part of the silicon dioxide (particles) can be carried out of the tail gas pipeline by the diluent gas. Since the solid substances such as silicon dioxide in the primary product cannot be completely carried out of the tail gas pipeline 2 by the diluent gas, some of them will remain in the tail gas pipeline, that is, the primary product remaining in the tail gas pipeline 2 may include silicon dioxide. Therefore, a second process gas and a dilution gas are introduced into the tail gas pipeline 2, and the second process gas further reacts with the primary product (mainly silicon dioxide) remaining in the tail gas pipeline 2 to generate a secondary product that can be carried out of the tail gas pipeline 2 by the dilution gas. In this scheme, hydrogen fluoride gas is mainly reacted with silicon dioxide remaining in the tail gas pipeline 2 to generate water, silicon tetrafluoride, fluorosilicic acid and other gases, that is, the second product includes silicon tetrafluoride, fluorosilicic acid gas and water vapor (the temperature required for the reaction of hydrogen fluoride gas and silicon dioxide can make the water in the product gaseous), so various products in the second product can be carried out of the tail gas pipeline 2 by the dilution gas.

[0060] In this embodiment, one end of the tail gas pipeline 2 is connected to the process chamber 1 through the isolation valve 4, and the other end of the tail gas pipeline 2 is connected to the tail gas collection system 9 through the exhaust pump 8; a pressure controller 3 is also provided between the isolation valve 4 and the process chamber 1;

[0061] The gas supply mechanism includes a dilution gas delivery pipeline 13, a first process gas delivery pipeline 14, a second process gas delivery pipeline 15 and a main pipeline 16;

[0062] One end of the dilution gas delivery pipeline 13 is connected to the dilution gas supply end 10, one end of the first process gas delivery pipeline 14 is connected to the first process gas supply end 11, and one end of the second process gas delivery pipeline 15 is connected to the second process gas supply end 12;

[0063] The other end of the dilution gas delivery pipeline 13, the other end of the first process gas delivery pipeline 14, and the other end of the second process gas delivery pipeline 15 are respectively connected to one end of the main pipeline 16;

[0064] The other end of the main pipeline 16 is communicated with the exhaust gas pipeline 2 .

[0065] Preferably, at least one switch function valve is provided on the exhaust gas pipeline 2; the gas supply mechanism also includes at least two branch pipelines, wherein one end of each of the at least two branch pipelines is connected to the main pipeline, and the other end of each branch pipeline is respectively connected to the exhaust gas pipeline, and a branch pipeline is connected between the isolation valve 4 and the switch function valve, between the switch function valve and the exhaust pump 8, and between adjacent switch function valves.

[0066] In this embodiment, the switch function valve may be a pneumatic valve or a throttle valve, etc.; for example, taking at least one switch function valve including a fifth pneumatic valve 5, a throttle valve 6, and a second pneumatic valve 7 disposed between the isolation valve 4 and the exhaust pump 8 as an example, three branch pipelines need to be provided, including a first branch pipeline 17, a second branch pipeline 18, and a third branch pipeline 19, wherein one end of the first branch pipeline 17 is connected to the other end of the main pipeline 16, and the other end of the first branch pipeline 17 is connected to the main pipeline 16 located between the isolation valve 4 and the fifth pneumatic valve 5;

[0067] One end of the second branch pipeline 18 is connected to the other end of the main pipeline 16, and the other end of the second branch pipeline 18 is connected to the main pipeline 16 located between the fifth pneumatic valve 5 and the throttle valve 6;

[0068] One end of the third branch pipe 19 is communicated with the other end of the main pipe 16 , and the other end of the third branch pipe 19 is communicated with the main pipe 16 between the second pneumatic valve 7 and the exhaust portion.

[0069] The dilution gas delivery pipeline 13 is provided with a first pneumatic valve 23 and a first mass flow controller 20;

[0070] The first process gas delivery pipeline 14 is provided with a second pneumatic valve 24 and a second mass flow controller 21;

[0071] The second process gas delivery pipeline 15 is provided with a third pneumatic valve 25 and a third mass flow controller 22;

[0072] Each branch pipeline is provided with a fourth pneumatic valve 26 and a first manual valve 27;

[0073] Preferably, a heating mechanism is further provided on the tail gas pipeline 2 in this embodiment, and the heating mechanism can be used to heat the tail gas pipeline 2 when hydrogen fluoride gas is introduced to accelerate the reaction of hydrogen fluoride and silicon oxide. The heating mechanism can be a heating belt wrapped around the outer wall of the tail gas pipeline 2, etc.

[0074] When cleaning the by-products deposited in the tail gas pipeline 2, the first pneumatic valve 23 can be controlled to open, the flow rate of the first mass flow controller 20 can be set, and nitrogen can be introduced into the tail gas pipeline 2; the second pneumatic valve 24 can be controlled to open, the flow rate of the second mass flow controller 21 can be set, and oxygen can be introduced into the tail gas pipeline 2; the third pneumatic valve 25 can be controlled to open, the flow rate of the third mass flow controller 22 can be set, and hydrogen fluoride can be introduced into the tail gas pipeline 2. The first hand valve 27 on each branch pipeline is in a normally open state, and the switch of the fourth pneumatic valve 26 on the three branch pipelines can be controlled to determine whether to pass the dilution gas, the first process gas and the second process gas into the fifth pneumatic valve 5, the throttle valve 6 or the exhaust pump 8 on the tail gas pipeline, so that the deposits can be cleaned in a targeted manner for different pipeline positions and different valves of the tail gas pipeline 2, so as to completely remove the by-products in the tail gas pipeline 2.

[0075] Oxygen is input into the exhaust gas pipeline 2 through the air supply mechanism, and oxygen reacts with phosphorus to generate phosphorus oxide (phosphorus pentoxide, phosphorus trioxide), and the reaction releases heat at the same time; heat promotes the reaction of oxygen with silicon and silicon tetrachloride to generate silicon dioxide and other substances; the exhaust gas pipeline can also be heated by the heating mechanism on the exhaust gas pipeline 2 to improve the reaction efficiency; the smoky phosphide, a small amount of silicon dioxide and reaction exhaust gas generated by the reaction of oxygen and phosphorus will be carried to the exhaust gas pipeline 2 by a large amount of nitrogen and absorbed by the exhaust gas adsorption system; then hydrogen fluoride is input into the exhaust gas pipeline 2 through the exhaust gas pipeline 2 air supply system to react with silicon dioxide, and the temperature of the exhaust gas pipeline 2 can be controlled by the heating device to promote the reaction; the product can also be carried out of the exhaust gas pipeline 2 by a large amount of nitrogen and absorbed by the exhaust gas adsorption system; by introducing secondary special gas into the composite reaction, phosphorus, silicon and silicon tetrachloride are reacted separately to generate gaseous or smoky fine particles, which are carried out of the exhaust gas pipeline 2, thereby realizing the cleaning of the by-products of the exhaust gas pipeline 2.

[0076] Example 2

[0077] like Figure 5 As shown, this embodiment provides a method for cleaning an exhaust gas pipeline. The exhaust gas pipeline is cleaned using the process chamber exhaust gas pipeline cleaning device of embodiment 1. The cleaning method of this embodiment includes:

[0078] S1: introducing a dilution gas and a first process gas into the tail gas pipeline 2, the first process gas reacts with the by-products in the tail gas pipeline 2 to generate a primary product that can be carried out of the tail gas pipeline 2 by the dilution gas, and the first process gas releases heat when reacting with the by-products. After the dilution gas and the first process gas are introduced for a first set time or when the temperature of the tail gas pipeline 2 rises to a first set temperature, the introduction of the first process gas is stopped;

[0079] In this step, the dilution gas is nitrogen, the first process gas is oxygen or compressed air, the first setting time is preferably 1-20 minutes, and the first setting temperature is preferably in the range of 150-200°C;

[0080] Specifically, the gas supply mechanism is used to open the first pneumatic valve 23, set the flow rate of the first mass flow controller 20, and introduce nitrogen; the second pneumatic valve 24 is opened, the flow rate of the second mass flow controller 21 is set, and oxygen or compressed air is introduced; oxygen (or oxygen in compressed air) reacts with phosphorus, silicon, silicon tetrachloride, etc. to generate smoke-like phosphide, silicon dioxide, Cl2, etc. When oxygen and nitrogen are introduced, the flow rate ratio of oxygen to nitrogen is preferably 1:9 to 1:24, and when compressed air and nitrogen are introduced, the flow rate ratio of compressed air to nitrogen is preferably 1:1-1:5; at the same time, preferably, the total flow rate of the introduced oxygen (or compressed air) and nitrogen is controlled at 10%-50% of the maximum flow rate of the process chamber 1.

[0081] By controlling the proportion of a smaller oxygen flow rate, it is possible to avoid excessive reaction between oxygen and by-products in the exhaust pipeline 2, excessive heat accumulation, and damage to the components of the exhaust pipeline 2; by controlling the total gas volume, the pipeline treatment products can be quickly and effectively removed, and it is beneficial for the exhaust gas collection system 9 to completely and effectively treat the exhaust gas.

[0082] Preferably, the time for introducing oxygen or compressed air is set at 1-20 minutes to achieve complete reaction between phosphorus, silicon, silicon tetrachloride, etc. on the surface of the inner wall of the pipeline and oxygen; or when the temperature of the tail gas pipeline 2 reaches 150-200°C, it means that oxygen has completely reacted with the by-products, and the introduction of oxygen or compressed air can also be stopped at this time.

[0083] In this embodiment, before executing step S1, the steps of pre-treatment of the reaction chamber and the tail gas pipeline 2 are also included, specifically including:

[0084] Dilution gas is introduced into the process chamber 1 and the exhaust gas pipeline 2 through the chamber air inlet to replace the epitaxial process gas in the exhaust gas pipeline 2 with dilution gas and reduce the temperature of the exhaust gas pipeline 2 to the fourth set temperature; then the chamber air inlet is closed and the isolation valve 4 is closed.

[0085] Specifically, first, the chamber intake is switched from hydrogen in the process state to nitrogen, the pressure is set to between 400-800 torr, and the flow rate is 10%-50% of the maximum flow rate of the chamber; then, nitrogen is pre-flowed through the chamber intake, and the duration of the pre-flow of nitrogen is preferably 10-60 minutes, so that the hydrogen in the process chamber 1 and the exhaust gas pipeline 2 is completely replaced, and at the same time, the temperature of the exhaust gas pipeline 2 is reduced to a fourth set temperature, preferably 50-100°C.

[0086] Afterwards, the chamber air intake is closed, and then the isolation valve 4 between the chamber and the exhaust gas pipeline 2 is closed to isolate the process chamber 1 and the exhaust gas pipeline to prevent the treated gas from the exhaust gas pipeline 2 from flowing back into the process chamber 1 and affecting the chamber environment.

[0087] S2: Continue to introduce the dilution gas into the tail gas pipeline 2, and evacuate the tail gas pipeline 2 to discharge the residual first process gas in the tail gas pipeline 2;

[0088] Specifically, this step is used to set the preconditions for the hydrogen fluoride process: close the second pneumatic valve 24, set the flow rate of the second mass flow controller 21 to 0 to interrupt the oxygen supply; keep the first pneumatic valve 23 open, the flow rate of the first mass flow controller 20 unchanged, continue to supply nitrogen for 1-5 minutes, and discharge the product in the tail gas pipeline 2; then vacuum the tail gas pipeline 2, control the pressure of the tail gas pipeline 2 to less than 1 torr, maintain for 10-60 seconds, and then raise the pressure of the tail gas pipeline 2 to the initial pressure of 400-800 torr. This step can exhaust the residual oxygen in the tail gas pipeline 2 to prevent oxygen from interfering with the reaction of the next step.

[0089] S3: Controlling the temperature of the tail gas pipeline 2 to a second set temperature, and stopping the introduction of the second process gas after introducing the dilution gas and the second process gas into the tail gas pipeline 2 for a second set time, so that the second process gas reacts with the primary product remaining in the tail gas pipeline 2 and generates a secondary product that can be carried out of the tail gas pipeline 2 by the dilution gas;

[0090] In this step, the flow ratio of the second process gas to the dilution gas is preferably in the range of 1:10-1:50, the second set temperature is preferably in the range of 100-150° C., and the second set time is preferably 1-20 minutes.

[0091] Specifically, the third pneumatic valve 25 is opened, and the flow rate of the third mass flow controller 22 is set according to the ratio of hydrogen fluoride to nitrogen of 1:10-1:50; the temperature of the tail gas pipeline 2 can be controlled at 100-150°C by the heating mechanism, and the hydrogen fluoride is kept flowing for 1-20 minutes, so that the hydrogen fluoride and the silicon dioxide remaining in the tail gas pipeline 2 in the product of step S1 are basically completely reacted to generate gaseous substances (including silicon tetrafluoride, fluorosilicic acid gas and water vapor), and the gaseous products are carried to the tail gas collection system 9 by nitrogen.

[0092] S4: Continue to introduce the dilution gas into the tail gas pipeline 2, and evacuate the tail gas pipeline 2 to completely discharge the residual second process gas in the tail gas pipeline 2;

[0093] Specifically, after the above treatment process is completed, the post-conditions of the exhaust pipeline 2 are set: the third pneumatic valve 25 is closed, the flow of the third mass flow controller 22 is set to 0, and the nitrogen flow rate is kept unchanged for 1-5 minutes; the exhaust pipeline 2 is then vacuumed to control the pressure in the exhaust pipeline 2 to less than 1 torr, and maintained for 10-60 seconds to ensure that the residual hydrogen fluoride and the generated exhaust gas in the exhaust pipeline 2 are completely discharged; then the pressure of the exhaust pipeline 2 is increased to the initial pressure of 400-800 torr.

[0094] S5: cyclically execute the above steps S1-S4 until the temperature of the tail gas pipeline 2 rises below the third set temperature after the dilution gas and the first process gas are introduced into the tail gas pipeline 2, and then stop the cycle. The third set temperature is preferably in the range of 0-10°C.

[0095] Specifically, the above steps S1-S4 are repeatedly executed in a cycle until the deposited materials in the exhaust pipe 2 are processed relatively cleanly without affecting the transport of by-products in the exhaust pipe 2; since the oxidation reaction between oxygen and the by-product phosphorus is exothermic, when step S1 is completed, if the temperature of the exhaust pipe 2 rises below 10°C, it indicates that the by-products are basically cleaned, and the operation of the cycle steps S1-S4 can be terminated at this time.

[0096] In this embodiment, after executing step S5, the method further includes:

[0097] Step S6: Restore the process state of the process chamber 1 by first opening the isolation valve 4 and then switching the chamber gas inlet of the process chamber 1 to a hydrogen atmosphere and a corresponding heating state to meet the epitaxial process start-up conditions.

[0098] Through the method of this embodiment, various deposition by-products such as phosphorus, silicon, and silicon tetrachloride can be processed, solving the problem of exhaust gas pipeline blockage in epitaxial machines in advanced integrated circuit manufacturing; at the same time, the processing method of this method is reaction processing, and there is no need to disassemble the exhaust gas pipeline, so it can effectively reduce maintenance time, improve machine utilization, and indirectly reduce manufacturing costs.

[0099] It should be noted that if oxygen, compressed air, hydrogen fluoride and other gases are introduced into the process chamber and the exhaust pipeline through the chamber air inlet pipeline of the process chamber to carry out reaction treatment of the by-products of the exhaust pipeline, the chamber deposits will react with oxygen, hydrogen fluoride, etc., affecting the stability of the chamber, and the purity of the oxygen and hydrogen fluoride in the exhaust treatment gas is relatively low, and impurities may be introduced into the chamber, causing contamination to the epitaxial process. The present invention uses an additionally arranged gas supply pipeline to separately transport the reaction gas to the exhaust pipeline, which can effectively avoid the above problems.

[0100] Example 3

[0101] This embodiment provides a semiconductor process equipment, including a process chamber 1, an exhaust gas pipeline 2 connected to the process chamber 1, and the process chamber exhaust gas pipeline cleaning device of embodiment 1.

[0102] The semiconductor process equipment of this embodiment may be chemical vapor deposition equipment, such as epitaxial process equipment, etc. By adopting the process chamber exhaust gas line cleaning device of Example 1, it is possible to effectively treat the deposition by-products in the process chamber exhaust gas line in advanced integrated circuit manufacturing: phosphorus, silicon, and silicon tetrachloride, solve the problem of exhaust gas line blockage, reduce maintenance difficulty and maintenance costs, and effectively improve machine utilization.

[0103] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A process chamber tail gas pipeline cleaning device, characterized in that: include: An air supply mechanism, the air supply mechanism is configured to communicate with the exhaust gas pipeline, and the air supply mechanism is used to: Introducing a dilution gas and a first process gas into the tail gas pipeline, so that the first process gas reacts with the by-products deposited in the tail gas pipeline to generate a primary product that can be carried out of the tail gas pipeline by the dilution gas; as well as, A dilution gas and a second process gas are introduced into the tail gas pipeline, so that the second process gas reacts with the primary product remaining in the tail gas pipeline to generate a secondary product that can be carried out of the tail gas pipeline by the dilution gas.

2. The process chamber exhaust pipeline cleaning device according to claim 1, characterized in that: One end of the tail gas pipeline is connected to the process chamber through an isolation valve, and the other end of the tail gas pipeline is connected to the tail gas collection system through an exhaust pump; The gas supply mechanism includes a dilution gas delivery pipeline, a first process gas delivery pipeline, a second process gas delivery pipeline and a main pipeline; One end of the dilution gas delivery pipeline is connected to the dilution gas supply end, one end of the first process gas delivery pipeline is connected to the first process gas supply end, and one end of the second process gas delivery pipeline is connected to the second process gas supply end; The other end of the dilution gas delivery pipeline, the other end of the first process gas delivery pipeline, and the other end of the second process gas delivery pipeline are respectively connected to one end of the main pipeline; The other end of the main pipeline is communicated with the exhaust pipeline.

3. The process chamber exhaust pipeline cleaning device according to claim 2, characterized in that: At least one switch function valve is arranged on the exhaust gas pipeline; The air supply mechanism also includes at least two branch pipelines, wherein one end of each of the at least two branch pipelines is connected to the main pipeline, and the other end of each branch pipeline is respectively connected to the exhaust gas pipeline, and one branch pipeline is connected between the isolation valve and the switching function valve, between the switching function valve and the exhaust pump, and between adjacent switching function valves.

4. The process chamber exhaust pipeline cleaning device according to claim 3, characterized in that: The dilution gas delivery pipeline is provided with a first pneumatic valve and a first mass flow controller; A second pneumatic valve and a second mass flow controller are provided on the first process gas delivery pipeline; A third pneumatic valve and a third mass flow controller are provided on the second process gas delivery pipeline; Each of the branch pipelines is provided with a fourth pneumatic valve and a first manual valve.

5. The process chamber exhaust pipeline cleaning device according to claim 1, characterized in that: The by-products include silicon, silicon tetrachloride and phosphorus.

6. The process chamber exhaust pipeline cleaning device according to claim 1, characterized in that: The dilution gas includes nitrogen, the first process gas includes oxygen or compressed air, and the second process gas includes hydrogen fluoride.

7. The process chamber exhaust pipeline cleaning device according to claim 1, characterized in that: The tail gas pipeline is also provided with a heating mechanism.

8. A method for cleaning an exhaust gas pipeline, characterized in that: The tail gas pipeline is cleaned by using the process chamber tail gas pipeline cleaning device according to any one of claims 1 to 7, and the cleaning method comprises: A dilution gas and a first process gas are introduced into the tail gas pipeline, the first process gas reacts with the by-product in the tail gas pipeline to generate a primary product that can be carried out of the tail gas pipeline by the dilution gas, the first process gas releases heat when reacting with the by-product, and after the dilution gas and the first process gas are introduced for a first set time or when the temperature of the tail gas pipeline rises to a first set temperature, the introduction of the first process gas is stopped; Continue to introduce the dilution gas into the tail gas pipeline, and evacuate the tail gas pipeline to discharge the first process gas remaining in the tail gas pipeline; Controlling the temperature of the tail gas pipeline to a second set temperature, and stopping the introduction of the second process gas after introducing the dilution gas and the second process gas into the tail gas pipeline for a second set time, so that the second process gas reacts with the primary product remaining in the tail gas pipeline and generates a secondary product that can be carried out of the tail gas pipeline by the dilution gas; Continue to introduce the dilution gas into the tail gas pipeline, and evacuate the tail gas pipeline to discharge the second process gas remaining in the tail gas pipeline; All the above steps are executed in a cycle until the dilution gas and the first process gas are introduced into the tail gas pipeline and the temperature of the tail gas pipeline rises below the third set temperature, and then the cycle is stopped.

9. The cleaning method according to claim 8, characterized in that: The tail gas pipeline is provided with an isolation valve, and before the dilution gas and the first process gas are introduced into the tail gas pipeline, the method further comprises: introducing the dilution gas into the process chamber and the tail gas pipeline through the chamber air inlet to replace the epitaxial process gas in the tail gas pipeline with the dilution gas and reduce the temperature of the tail gas pipeline to a fourth set temperature, wherein the fourth set temperature is lower than the first set temperature; Shut off the chamber air intake and close the isolation valve.

10. The cleaning method according to claim 8, characterized in that: The dilution gas is nitrogen, the first process gas is oxygen, and in the step of introducing the dilution gas and the first process gas into the tail gas pipeline, the flow ratio of the first process gas to the dilution gas is in the range of 1:9-1:24; Alternatively, the dilution gas is nitrogen, the first process gas is compressed air, and in the step of introducing the dilution gas and the first process gas into the exhaust pipeline, the flow ratio of the first process gas to the dilution gas is in the range of 1:1-1:

5.

11. The cleaning method according to claim 10, characterized in that: In the step of introducing the dilution gas and the first process gas into the tail gas pipeline, the total flow of the first process gas and the dilution gas is 10%-50% of the maximum flow of the process chamber.

12. The cleaning method according to claim 8, characterized in that: The dilution gas is nitrogen, and the second process gas is hydrogen fluoride; In the step of introducing the dilution gas and the second process gas into the tail gas pipeline, the flow ratio of the second process gas to the dilution gas is in the range of 1:10-1:

50.

13. The cleaning method according to claim 8, characterized in that: The first set temperature ranges from 150-200°C; the second set temperature ranges from 100-150°C; and the third set temperature ranges from 0-10°C.

14. A semiconductor process equipment, characterized in that: It includes a process chamber, an exhaust gas pipeline connected to the process chamber, and a process chamber exhaust gas pipeline cleaning device as described in any one of 1-7.

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