Lifting pin device, semiconductor process equipment and pressure control method

Abstract

The invention discloses a lifting pin device, semiconductor process equipment and a pressure control method, and relates to the field of semiconductors. A lifting pin device comprises an ejector pin assembly used for lifting a wafer and a gas transmission assembly. The ejector pin assembly is provided with an air channel, the first end of the air channel is used for making contact with a wafer, the second end of the air channel is connected with the air conveying end of the air conveying assembly, and the air conveying assembly is used for inflating the air channel and / or exhausting air from the air channel. According to the invention, at least the problems of random movement of the wafer or adhesion between the wafer and the three pins can be solved.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor technology, and specifically relates to a needle lift device, semiconductor process equipment and a pressure control method. Background Art

[0002] In the IC (integrated circuit) manufacturing process, the degumming chamber is generally used to remove the photoresist and chlorine-containing reaction byproducts on the surface of the wafer after metal etching. In the degumming machine reaction chamber structure, the mechanical chuck is an important device for receiving the wafer. It has the characteristics of low cost and low processing difficulty. The three-pin mechanism is a mechanical device placed in the mechanical chuck interface plate to assist in wafer transmission. It is evenly distributed in three positions of the mechanical chuck. At present, most of the three-pins are driven by cylinders or electric cylinders. When the robot transfers the wafer into the degumming chamber (PM), the three pins rise, the robot places the wafer on the top of the three pins, and then the chamber is evacuated. When the chamber pressure reaches the background pressure, the three pins are lowered and placed on the surface of the mechanical chuck and inside the focus ring to complete the pin lowering process.

[0003] Since the wafer is supported at the top of the three pins, the wafer is prone to slide at the top of the three pins during the process of lifting the wafer, thus affecting the wafer position accuracy; in addition, in some cases, adhesion is likely to occur between the wafer and the top surface of the three pins, making it easy for the wafer to break during the process of removing the wafer.

[0004] In the above process, the general degumming process takes only about 30 seconds, while the needle lowering process takes about 3 seconds, which seriously affects the number of wafers per hour (WPH) of the degumming machine. If the needle is lowered at the same time during the vacuuming process, that is, the vacuuming and needle lowering are carried out in parallel, due to the air cushion effect, the wafer will slide on the surface of the mechanical chuck and even collide with the focus ring, affecting the number of particles and process uniformity of the machine; in addition, during the wafer removal process, it is easy for the wafer to stick to the three needles, which can easily cause problems such as wafer damage. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a lifting needle device, semiconductor process equipment and pressure control method, which can at least solve the problems of random movement of the wafer or adhesion between the three needles.

[0006] In order to solve the above technical problems, this application is implemented as follows:

[0007] The embodiment of the present application provides a lifting pin device, comprising: a pin assembly for lifting a wafer, and a gas delivery assembly;

[0008] The ejector pin assembly has an air channel, a first end of the air channel is used to contact the wafer, a second end of the air channel is connected to the air delivery end of the air delivery assembly, and the air delivery assembly is used to inflate the air channel and / or extract air from the air channel.

[0009] The embodiment of the present application also provides a semiconductor process equipment, including: a process chamber, a control system, and the above-mentioned lifting seat device;

[0010] The process chamber comprises a reaction chamber and a carrying component, wherein the carrying component is arranged in the reaction chamber and is used to carry the wafer;

[0011] The lifting needle device comprises a plurality of ejector pin assemblies, each of the ejector pin assemblies comprises an ejector pin, and the ejector pins of the plurality of ejector pin assemblies are respectively liftable and pass through the bearing component, and the air passage at least passes through the ejector pin;

[0012] The gas delivery component is communicated with the reaction chamber and the gas channel respectively;

[0013] The control system includes a control element and a first detection element and a second detection element electrically connected to the control element respectively, the first detection element is used to detect the pressure in the reaction chamber, and the second detection element is used to detect the pressure in the airway, and the control element is used to control the gas delivery component according to the pressure difference between the pressures detected by the first detection element and the second detection element, so as to adjust the pressure difference through the gas delivery component so that the pressure difference is within a preset range.

[0014] The embodiment of the present application also provides a pressure control method, which is applied to a process of placing a wafer and lowering a needle or a process of taking a wafer and raising a needle in a semiconductor process equipment. The pressure control method includes:

[0015] During the film placement and needle lowering process:

[0016] Slowly evacuate the reaction chamber and the airway, and control the opening and closing of the air extraction switching valve in the gas delivery component based on the fuzzy control algorithm so that the pressure difference between the pressure in the reaction chamber and the pressure in the airway is within a preset range;

[0017] Controlling the descent of multiple ejector pin assemblies of the needle lifting device;

[0018] Controlling the reaction chamber to be quickly evacuated;

[0019] When the pressure in the reaction chamber drops to less than or equal to the first pressure value, the exhaust switching valve is controlled to switch to a fully open state until the pressure in the reaction chamber drops to the pressure control pressure required by the process;

[0020] During the film removal and needle lifting process:

[0021] Slowly inflate the reaction chamber, stop evacuating the airway, and control the opening and closing of the inflation switching valve in the gas delivery component based on the fuzzy control algorithm so that the pressure difference between the pressure in the reaction chamber and the pressure in the airway is within a preset range;

[0022] Controlling the multiple ejector pin assemblies of the needle lifting device to rise;

[0023] Controlling the rapid inflation of the reaction chamber;

[0024] When the pressure in the reaction chamber rises to a third pressure value, the inflation switching valve is controlled to switch to a fully open state until the pressure in the reaction chamber rises to a film taking pressure.

[0025] In an embodiment of the present application, the wafer can be supported and driven to rise and fall by the ejector pin assembly, wherein the ejector pin assembly has an airway, the first end of which is used to contact the wafer, and the second end of the airway is connected to the air delivery end of the air delivery assembly. Based on this, the air delivery assembly can be used to evacuate air from the airway to form a negative pressure area near the first end of the airway, so that the surface of the wafer can be adsorbed to ensure the relative stability between the wafer and the ejector pin assembly and prevent the wafer from sliding, thereby ensuring the position accuracy of the wafer. In addition, the airway can be inflated by the air delivery assembly, and air can be blown to the surface of the wafer facing the first end of the airway through the airway to increase the gas pressure in the area, and the problem of adhesion between the airway and the wafer surface caused by the residual vacuum degree during the extraction process can be alleviated, thereby promoting the separation of the wafer and the ejector pin assembly, so that the wafer can be removed from the end of the ejector pin assembly without adhesion, and the integrity of the wafer can be ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the structure of a semiconductor process equipment disclosed in an embodiment of the present application;

[0027] Figure 2 This is a schematic diagram of the structure of the air box disclosed in the embodiment of the present application;

[0028] Figure 3 It is a schematic diagram of the structure of the ejector pin assembly disclosed in the embodiment of the present application;

[0029] Figure 4 A schematic diagram of a circuit disclosed in an embodiment of the present application;

[0030] Figure 5 This is a flow chart of the robot placing the film and lowering the needle disclosed in the embodiment of the present application;

[0031] Figure 6 This is a flow chart of the robot taking the film and raising the needle disclosed in the embodiment of the present application;

[0032] Figure 7 This is a schematic diagram of the triangular membership function disclosed in the embodiment of the present application.

[0033] Description of reference numerals:

[0034] 100-process chamber; 110-reaction chamber; 120-carrying component;

[0035] 200-thimble assembly; 210-thimble; 220-airway; 230-bellows; 240-thimble guide shaft;

[0036] 300-gas transmission assembly;

[0037] 310 - first inflation path; 311 - first inflation pipeline; 312 - inflation switching valve; 313 - throttle valve;

[0038] 320 - first air extraction path; 321 - first air extraction pipeline; 322 - air extraction switching valve; 323 - one-way valve;

[0039] 330 - second inflation path; 331 - second inflation pipeline; 3311 - first inflation branch; 3312 - second inflation branch; 332 - slow inflation valve; 333 - fast inflation valve;

[0040] 340 - second air extraction path; 341 - second air extraction pipeline; 342 - angle valve;

[0041] 400-air box; 410-airway interface; 420-inflating interface; 430-exhaust interface;

[0042] 500 - control system; 510 - control element; 520 - first detection element; 530 - second detection element; 540 - solenoid valve group. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0045] The embodiments of the present application are described in detail below through specific embodiments and their application scenarios in conjunction with the accompanying drawings.

[0046] In order to solve the problem that the wafer is prone to slipping on the ejector pin assembly 200, or the wafer and the ejector pin assembly 200 are adhered to each other, refer to Figures 1 to 7 The embodiment of the present application discloses a lifting needle device, which includes a pin assembly 200 for lifting a wafer and a gas delivery assembly 300, wherein the pin assembly 200 can support the wafer and drive the wafer to lift and lower, so as to facilitate the wafer to be taken and placed and meet the process requirements of the wafer; the gas delivery assembly 300 is used to transmit gas, wherein the gas delivery assembly 300 can be used for inflation or for exhaustion, and the specific selection can be based on the actual working conditions.

[0047] The ejector pin assembly 200 has an air channel 220, and the first end of the air channel 220 is used to contact the wafer. Exemplarily, when the wafer is placed on the end face of the ejector pin assembly 200, at least part of the surface of the wafer is arranged opposite to the first end of the air channel 220, and the surface of the wafer also shields the port at the first end of the air channel 220. In addition, a groove with a cross-sectional area greater than the cross-sectional area of ​​the air channel 220 may be provided at the port at the first end of the air channel 220, and the notch of the groove is opposite to the surface of the wafer, so that the overlap area between the first end of the air channel 220 and the surface of the wafer can be increased, which can increase the adsorption effect on the wafer to a certain extent or promote the wafer to be separated from the ejector pin assembly 200.

[0048] For example, reference Figure 3, the ejector assembly 200 may include an ejector 210 (such as a ceramic needle, etc.), a bellows 230, an ejector guide shaft 240 and other components. Of course, the ejector assembly 200 may also include other structures, and its specific structure may also refer to the relevant technology. In the embodiment of the present application, the ejector assembly 200 is provided with an air duct 220, wherein the diameter of the air duct 220 may be 3 mm, and of course, it may be other sizes, which are not specifically limited here. In addition, the air duct 220 passes through the ejector 210, the bellows 230 and the ejector guide shaft 240 along the axial direction of the ejector assembly 200. This arrangement will not destroy the vacuum or atmospheric state of various parts of the ejector assembly 200, and the ejector 210 can also perform lifting and lowering movements.

[0049] In some embodiments, the lifting pin device may include multiple ejector pin assemblies 200, and the multiple ejector pin assemblies 200 may be distributed in a triangular shape on the supporting component 120. The ejector pins 210 of each of the three ejector pin assemblies 200 may pass through the supporting component 120 respectively to contact the wafer and support and lift the wafer.

[0050] The second end of the air channel 220 is connected to the air delivery end of the air delivery component 300, and the air channel 220 can be inflated or exhausted through the air delivery component 300. When the air delivery component 300 exhausts air from the surface of the wafer through the air channel 220, a negative pressure area can be formed near the first end of the air channel 220. Since the first end of the air channel 220 is opposite to and in contact with the wafer, the wafer will be adsorbed to a certain extent under the action of the negative pressure, thereby increasing the relative sliding resistance between the wafer and the ejector pin component 200, that is, the wafer can be prevented from sliding on the ejector pin component 200 and changing the position of the wafer.

[0051] When the gas delivery component 300 inflates the wafer surface through the air channel 220, a positive pressure area can be formed near the first end of the air channel 220. Since the first end of the air channel 220 is opposite to and in contact with the wafer, the adsorption effect of the first end of the air channel 220 on the wafer can be eliminated under the action of the positive pressure, and a pushing force can be generated on the wafer, thereby promoting the wafer to separate from the ejector pin component 200 to prevent the wafer from being adhered to the ejector pin component 200 due to vacuum adsorption, thereby effectively alleviating the problem of damage to the wafer caused by the adhesion between the wafer and the ejector pin component 200 during the process of removing the wafer, thereby ensuring the integrity of the wafer.

[0052] In the embodiment of the present application, the wafer can be supported by the ejector pin assembly 200 and driven to rise and fall, wherein the ejector pin assembly 200 has an air duct 220, a first end of which is used to contact the wafer, and a second end of the air duct 220 is connected to the air delivery end of the air delivery assembly 300.

[0053] Based on the above configuration, the gas delivery assembly 300 can be used to draw air from the air channel 220, so that a negative pressure area is formed near the first end of the air channel 220, so that the surface of the wafer can be adsorbed to ensure the relative stability between the wafer and the ejector assembly 200 and prevent the wafer from sliding, thereby ensuring the position accuracy of the wafer. In addition, the air channel 220 can be inflated through the gas delivery assembly 300, and air can be blown to the surface of the wafer facing the first end of the air channel 220 through the air channel 220 to increase the gas pressure in the area, and the problem of adhesion between the wafer and the ejector assembly 200 caused by the residual vacuum degree between the air channel 220 and the wafer surface during the extraction process can be alleviated, thereby promoting the separation of the wafer and the ejector assembly 200, so that the wafer can be removed from the end of the ejector assembly 200 without adhesion, and the integrity of the wafer can be ensured.

[0054] To realize the inflation function and the exhaust function of the gas delivery component 300, as Figure 1 As shown, the gas delivery component 300 in the embodiment of the present application may include a first inflation path 310 and a first exhaust path 320 , wherein the first inflation path 310 is used to inflate the airway 220 , and the first exhaust path 320 can exhaust air from the airway 220 .

[0055] The needle lifting device may further include an air box 400, which is located between the first gas charging path 310 and the air channel 220, and between the first gas exhaust path 320 and the air channel 220. In this way, the air path volume of the ejector assembly 200 can be increased by the air box 400, thereby effectively alleviating the pressure change rate in the air path of the ejector assembly 200. In addition, the volume of the air box 400 can be selected according to actual working conditions. For example, when the needle lifting device is applied to the process chamber 100 of the semiconductor process equipment, in order to achieve better pressure difference control, the volume of the air box 400 can be designed to be 1 / 10 of the volume of the process chamber 100. Of course, it is not limited to this, and can also be other ratios, which are not limited here.

[0056] To achieve gas conduction, the gas box 400 may be provided with an airway interface 410, a gas charging interface 420 and a gas extraction interface 430, such as Figure 2 As shown, the second end of the air channel 220 is in communication with the air channel interface 410, the first air charging path 310 is in communication with the air charging interface 420, and the first air extraction path 320 is in communication with the air extraction interface 430. Based on this arrangement, the first air extraction path 320 can extract gas from the air box 400 via the air extraction interface 430. At the same time, the pressure in the air box 400 is reduced, and air is extracted from the surface of the wafer facing the ejector assembly 200 through the air channel 220. In this way, a negative pressure area can be formed on the surface of the wafer, so that a certain adsorption effect can be exerted on the wafer air channel 220 to prevent the wafer from sliding freely relative to the ejector assembly 200 and affecting the position accuracy of the wafer.

[0057] In some embodiments, the needle lifting device may include multiple ejector pin assemblies 200. Accordingly, the air box 400 may be provided with multiple airway interfaces 410, and the second ends of the airways 220 of the multiple ejector pin assemblies 200 may be communicated with the corresponding airway interfaces 410. Of course, in other embodiments, the airways 220 of the multiple ejector pin assemblies 200 may also be communicated with the same airway interface 410.

[0058] The first inflation path 310 can fill gas into the air box 400 via the inflation interface 420, and make the gas flow into the airway 220 via the airway interface 410, and finally be transported to the surface of the wafer facing the ejector pin assembly 200 via the airway 220, so that a positive pressure area can be generated near the surface of the wafer. On the one hand, the negative pressure generated by the previous vacuum can be offset, and on the other hand, the positive pressure can also push the airway 220 on the wafer surface to promote the separation of the wafer and the ejector pin assembly 200.

[0059] It should be noted that when the air channel 220 is directly connected to the dry pump, the air channel 220 will directly reduce its internal pressure to less than 200mTorr due to its limited volume, and the wafer will be greatly deformed due to the 734Torr pressure difference between the upper and lower surfaces, thereby damaging the internal microstructure of the wafer. Based on this, in the embodiment of the present application, the air channel 220 is first connected to the air box 400 and then to the dry pump.

[0060] Exemplarily, the air box 400 can be a rectangular air box, a cube air box, a cylindrical air box, a spherical air box, etc. Of course, it can also be other shapes, which are not specifically limited here. In addition, the airway interface 410, the inflation interface 420 and the air extraction interface 430 can be respectively located on the side wall of the air box 400, and of course, they can also be located at other positions. In addition, the air box 400 can be a sealed metal container with a leakage rate of less than 5mTorr / min to ensure that the airway 220 is leak-proof.

[0061] In addition, in order to detect the gas pressure in the gas box 400 and thus indirectly obtain the gas pressure in the gas passage 220, in some embodiments, the gas box 400 may also be provided with a pressure sensor, wherein the detection end of the pressure sensor extends into the interior of the gas box 400, so as to facilitate real-time detection of the gas pressure inside the gas box 400, thereby indirectly obtaining the gas pressure in the gas passage 220, so as to facilitate subsequent control of the pressure on the surface area of ​​the wafer facing the ejector pin assembly 200 to prevent the pressure from being too high or too low.

[0062] refer to Figure 1In some embodiments, the first gas-charging path 310 may include a first gas-charging pipeline 311 and a gas-charging switching valve 312, wherein one end of the first gas-charging pipeline 311 is connected to the gas-charging interface 420, the other end of the first gas-charging pipeline 311 is used to input gas, and the gas-charging switching valve 312 is provided on the first gas-charging pipeline 311. To achieve gas-charging, the other end of the first gas-charging pipeline 311 may be connected to a gas-charging device, such as a gas pump, etc., and may also be connected to a gas storage device, such as a gas storage tank, etc., so as to deliver pressurized gas to the first gas-charging pipeline 311. Exemplarily, the pressurized gas may be nitrogen, and of course, other gases may also be used, as long as they can meet the process requirements, and the specific type is not limited.

[0063] The pressurized gas can enter the inflation interface 420 through the first inflation pipeline 311, flow into the gas box 400 from the inflation interface 420, then flow into the airway 220 from the airway interface 410, and finally be transported to the wafer surface through the airway 220 to form a positive pressure area on the wafer surface.

[0064] The inflation switching valve 312 can be used to control the gas pressure (or gas flow) in the first inflation pipeline 311, so as to indirectly control the gas pressure in the airway 220 during the inflation process. In some cases, the inflation switching valve 312 is required to quickly switch on and off the gas in the first inflation pipeline 311. In this way, in the embodiment of the present application, the response time of the inflation switching valve 312 can be less than 20ms. For example, FITOK's ALD6LW-FR4-4-CF3MOV can be selected, with a switching action time of less than 10ms and a 24VDO output to meet the process requirements.

[0065] Furthermore, the first inflation path 310 may also include a throttle valve 313, which is provided in the first inflation pipeline 311, and the throttle valve 313 is located downstream of the inflation switching valve 312 along the inflation direction. Through the action of the throttle valve 313, the flow rate of the pressurized gas in the first inflation pipeline 311 can be limited, thereby effectively preventing the problem that the pressure inside the air box 400 is rapidly increased due to the pressurized gas in the first inflation pipeline 311 entering the air box 400. Exemplarily, the throttle valve 313 can be a needle valve, and of course, other types of valve bodies can also be used, which can be selected according to actual working conditions.

[0066] Continue to refer Figure 1 In some embodiments, the first air extraction path 320 may include a first air extraction pipeline 321 and an air extraction switching valve 322, wherein one end of the first air extraction pipeline 321 is connected to the air extraction interface 430, the other end of the first air extraction pipeline 321 is used to output gas, and the air extraction switching valve 322 is provided on the first air extraction pipeline 321. To achieve air extraction, the other end of the first air extraction pipeline 321 may be connected to an air extraction device, such as an air extraction pump.

[0067] The gas in the wafer surface area is sucked into the gas box 400 through the air channel 220, then flows into the first exhaust pipe 321 through the exhaust interface 430, and finally discharged through the first exhaust pipe 321, so as to form a negative pressure area on the wafer surface.

[0068] The inflation switching valve 312 can be used to control the gas pressure (or gas flow) in the first exhaust pipeline 321, so as to indirectly control the gas pressure in the gas channel 220 during the exhaust process. In some cases, the exhaust switching valve 322 is required to quickly switch on and off the gas in the first exhaust pipeline 321. In this way, in the embodiment of the present application, the response time of the exhaust switching valve 322 can be less than 20ms. For example, FITOK's ALD6LW-FR4-4-CF3MOV can be selected, with a switching action time of less than 10ms and a 24VDO output to meet the process requirements.

[0069] Furthermore, the first exhaust path 320 may further include a one-way valve 323, which is disposed on the first exhaust pipeline 321 and is located downstream of the exhaust switching valve 322 along the exhaust direction. The one-way valve 323 can effectively prevent the exhaust path from being reversed when the reaction chamber is evacuated.

[0070] Based on the above-mentioned needle lifting device, the embodiment of the present application also discloses a semiconductor process equipment, such as Figures 1 to 7 As shown, the disclosed semiconductor process equipment includes a process chamber 100, a control system 500 and the above-mentioned lifting needle device.

[0071] The process chamber 100 may include a reaction chamber 110 and a carrying component 120. The carrying component 120 is disposed in the reaction chamber 110 and is used to carry a wafer. The reaction chamber 110 is used to provide a space for the process of the wafer. For example, the carrying component 120 may be a carrying plate, and the wafer is carried by the carrying plate so that the wafer can undergo a process reaction in the reaction chamber 110.

[0072] In order to be able to lift the wafer from the carrier component 120, or to place the wafer on the carrier component 120, the lifting needle device may include a plurality of ejector pin assemblies 200, and the plurality of ejector pin assemblies 200 cooperate with each other to support and lift the wafer. In some embodiments, the lifting needle device may include three ejector pin assemblies 200, and the heat dissipation ejector pin assemblies 200 may be respectively located at the three vertices of an equilateral triangle. This arrangement can ensure the stability of the wafer support. Of course, the lifting needle device may also include other numbers of ejector pin assemblies 200, or use ejector pin assemblies 200 in other arrangements, as long as they can ensure the stability of the wafer, and the specific number and form are not limited.

[0073] Each ejector pin assembly 200 may include an ejector pin 210, and the ejector pins 210 of each of the multiple ejector pin assemblies 200 may be raised and lowered to pass through the supporting component 120, so that the wafer may be supported and carried by the ejector pins 210 of each of the multiple ejector pin assemblies 200, and the wafer may be raised and lowered along with the raising and lowering of the ejector pins 210, so that the wafer may be placed on the supporting component 120 or lifted from the surface of the supporting component 120.

[0074] Exemplarily, the ejector assembly 200 may further include a driving part, which is connected to the ejector 210 to drive the ejector 210 to move up and down. The driving part may be a cylinder, a hydraulic cylinder, an electric cylinder, etc., which may be selected according to actual working conditions.

[0075] Considering that the wafer is supported by the ejector pins 210, in order to enable the gas to be transported to the area on the side of the wafer facing the ejector pin assembly 200, or to enable the gas in the area on the side of the wafer facing the ejector pin assembly 200 to be extracted, the gas channel 220 at least penetrates the ejector pin 210, that is, the ejector pin 210 of each ejector pin assembly 200 is penetrated by the gas channel 220. In this way, the pressurized gas can be transported to the area on the side of the wafer facing the ejector pin assembly 200 through the gas channel 220, so as to prevent the wafer and the ejector pin 210 from sticking together; of course, the gas in the area on the side of the wafer facing the ejector pin assembly 200 can also be extracted through the gas channel 220 to ensure that the wafer can be firmly adsorbed on the end of the ejector pin 210.

[0076] In some embodiments, the gas delivery component 300 is connected to the reaction chamber 110 and the gas channel 220, respectively. Based on this, the reaction chamber 110 can be charged with gas through the gas delivery component 300, and of course, the gas channel 220 can also be charged with gas. In addition, gas can be sucked from the reaction chamber 110, and of course, the gas channel 220 can also be sucked from the gas delivery.

[0077] To achieve automatic control, the control system 500 may include a control element 510, a first detection element 520, and a second detection element 530, wherein the first detection element 520 and the second detection element 530 are both connected to the control element 510, such as electrically connected or signal connected, etc. The first detection element 520 is used to detect the pressure in the reaction chamber 110, and the second detection element 530 is used to detect the pressure in the airway 220.

[0078] Based on the above settings, the control element 510 is used to control the gas delivery component 300 according to the pressure difference detected by the first detection element 520 and the second detection element 530, so as to adjust the speed pressure through the gas delivery component 300 so that the pressure difference is within the range.

[0079] Exemplarily, both the first detection element 520 and the second detection element 530 can be pressure sensors, and of course, can also be other components, which are not specifically limited here. Among them, when the first detection element 520 is a pressure sensor, it can choose the MKS 275620-2-GD-T model, with a range of 0-1000Torr, an accuracy of 1mTorr, and a communication method of Ethercat. When the second detection element 530 is a pressure sensor, it can choose the MKS 275620-2-GD-T model, with a range of 0-1000Torr, an accuracy of 1mTorr, and a communication method of Ethercat.

[0080] In some embodiments, the first detection element 520 may be disposed in the reaction chamber 110, and the detection end of the first detection element 520 may extend to the interior of the reaction chamber 110, so as to detect the pressure in the reaction chamber 110. The second detection element 530 may be disposed in the gas box 400 of the needle lifting device, and the detection end of the second detection element 530 may extend to the interior of the gas box 400, so as to detect the pressure in the gas box 400. It should be noted here that the gas box 400 is connected to the gas channel 220 through the gas channel interface 410, so that the pressure in the gas channel 220 can be indirectly known through the second detection element 530, so as to control the pressure of the wafer surface area.

[0081] In the embodiment of the present application, the first detection element 520 and the second detection element 530 can respectively send the pressure parameters detected by each to the control element 510, and the control element 510 calculates, processes, and analyzes the pressure parameters, and determines the pressure difference between the pressure in the gas channel 220 and the pressure in the reaction chamber 110; the control element 510 controls the gas delivery component 300 according to the pressure difference, so as to adjust the pressure difference through the gas delivery component 300 so that the pressure difference is within a preset range. It should be noted here that when the pressure difference is within the preset range, it indicates that the pressure in the gas channel 220 is not much different from the pressure in the reaction chamber 110. In this case, even if the wafer is driven to move up and down by the ejector pin assembly 200, the wafer will not slide freely on the ejector pin assembly 200.

[0082] In order to inflate the reaction chamber 110, the gas delivery assembly 300 may further include a second gas filling path 330, such as Figure 1As shown, one end of the second gas filling path 330 is connected to the reaction chamber 110, and the other end of the second gas filling path 330 is used to input gas. When gas filling is required, gas can be filled into the reaction chamber 110 through the second gas filling path 330 to increase the pressure in the reaction chamber 110. Exemplarily, one end of the second gas filling path 330 can extend to the interior of the reaction chamber 110. In addition, nitrogen or other gases can be filled into the reaction chamber 110 through the second gas filling path 330 to meet the process requirements.

[0083] In some embodiments, the second gas charging path 330 may include a second gas charging line 331, a slow charging valve 332, and a fast charging valve 333, wherein the second gas charging line 331 is connected to the reaction chamber 110 to facilitate the filling of gas into the reaction chamber 110. In addition, the second gas charging line 331 may include a first gas charging branch 3311 and a second gas charging branch 3312, and the first gas charging branch 3311 and the second gas charging branch 3312 are arranged in parallel with each other.

[0084] In addition, the slow filling valve 332 is arranged on the first inflation branch 3311, and the fast filling valve 333 is arranged on the second inflation branch 3312. The opening and closing of the slow filling valve 332 can control the on-off of the first inflation branch 3311, and the opening and closing of the fast filling valve 333 can control the on-off of the second inflation branch 3312.

[0085] Based on the above configuration, gas can be charged into the reaction chamber 110 through the second gas charging pipeline 331 to increase the pressure in the reaction chamber 110; in addition, when the reaction chamber 110 needs to be slowly charged, the slow charging valve 332 can be controlled to open and the fast charging valve 333 can be closed. At this time, the reaction chamber 110 can be charged by the first gas charging branch 3311; when the reaction chamber 110 needs to be quickly charged, the fast charging valve 333 can be controlled to open and the slow charging valve 332 can be closed. At this time, the reaction chamber 110 can be charged by the second gas charging branch 3312. Based on this, by switching between slow charging and fast charging, the charging requirements in different stages can be met.

[0086] Exemplarily, both the slow filling valve 332 and the fast filling valve 333 may be pneumatic diaphragm valves. Of course, they may also be other types of valve bodies, which are not specifically limited here.

[0087] In the embodiment of the present application, the control system 500 may further include a solenoid valve group 540, which is electrically connected to the control element 510 and to the slow filling valve 332 and the fast filling valve 333, respectively, and is used to switch the states of the slow filling valve 332 and the fast filling valve 333 under the control of the control element 510. Exemplarily, the solenoid valve group 540 needs to be stable in operation, and it can use SMC's EX160, and the communication method is Ethercat. Of course, other types of solenoid valve groups 540 or other communication methods can also be used, which can be selected according to actual working conditions.

[0088] In order to evacuate the reaction chamber 110, the gas delivery assembly 300 may further include a second gas extraction path 340, one end of which is connected to the reaction chamber 110, and the other end of the second gas extraction path 340 is used to output gas. When gas extraction is required, gas can be extracted from the reaction chamber 110 through the second gas extraction path 340 to reduce the pressure in the reaction chamber 110. Exemplarily, one end of the second gas extraction path 340 may extend to the interior of the reaction chamber 110; in addition, the other end of the second gas extraction path 340 may be connected to a gas extraction pump, such as a dry pump, so as to facilitate gas extraction of the reaction chamber 110.

[0089] In some embodiments, the second gas extraction path 340 may include a second gas extraction pipeline 341 and an angle valve 342 , wherein the second gas extraction pipeline 341 is connected to the reaction chamber 110 to extract gas from the reaction chamber 110 .

[0090] The angle valve 342 is provided in the second air extraction pipeline 341. The angle valve 342 has a slow extraction valve position and a fast extraction valve position. By switching between the slow extraction valve position and the fast extraction valve position, the air extraction state in the second air extraction pipeline 341 can be changed. When the angle valve 342 is switched to the slow extraction valve position, it can be used to roughly evacuate the reaction chamber 110; when the angle valve 342 is switched to the fast extraction valve position, it can be used to quickly evacuate the reaction chamber 110. Exemplarily, the slow extraction valve position and the fast extraction valve position in the angle valve 342 can both be start valve positions.

[0091] In the embodiment of the present application, the control system 500 may further include a solenoid valve group 540, which is electrically connected to the control element 510 and to the angle valve 342, and is used to switch the state of the angle valve 342 under the control of the control element 510. Based on this, under the control of the control element 510, the solenoid valve group 540 can control the opening and closing state of the angle valve 342, and control the angle valve 342 to switch between the slow pumping valve position and the fast pumping valve position to meet the air extraction requirements under different working conditions.

[0092] In some embodiments, in order to prevent the wafer from slipping during the lifting and lowering of the ejector pin assembly 200, when the lifting pin device drives the wafer to lift and lower, the pressure difference between the pressure in the air duct 220 (i.e., the pressure detected by the second detection element 530) and the pressure in the reaction chamber 110 (i.e., the pressure detected by the first detection element 520) can range from 25 Torr to 35 Torr, for example, including: 25 Torr, 27 Torr, 30 Torr, 32 Torr, 35 Torr, etc. Of course, it can also be other values, which are not specifically limited here.

[0093] Based on the above configuration, a certain restraining effect can be exerted on the wafer to alleviate the problem of the wafer sliding on the ejector pin assembly 200 .

[0094] It should be noted here that under the action of the above-mentioned pressure difference, the wafer will generate a certain extrusion force between it and the ejector pin assembly 200, and there is a friction coefficient between the two, which makes a certain friction force between the wafer and the ejector pin assembly 200 to prevent the wafer from sliding relative to the ejector pin assembly 200.

[0095] To prevent the wafer from breaking or sliding when taking it out, when the wafer is taken out from the lifting needle device, the pressure difference between the pressure in the air duct 220 (i.e., the pressure detected by the second detection element 530) and the pressure in the reaction chamber 110 (i.e., the pressure detected by the first detection element 520) ranges from 1 Torr to 5 Torr (i.e., the preset range of the pressure difference), including, for example: 1 Torr, 2 Torr, 3 Torr, 4 Torr, 5 Torr, etc. Of course, it can also be other values, which are not specifically limited here.

[0096] Based on the above configuration, during the wafer removal process, the problem of the wafer being easily broken due to excessive adsorption of the ejector pin assembly 200 can be effectively alleviated, and the problem of the wafer being easily slipped due to insufficient adsorption of the ejector pin assembly 200 can also be effectively alleviated.

[0097] It should be noted here that the range of the above pressure differences is related to the specifications of the wafer, including: the type, thickness, diameter size and other factors of the wafer. Taking an ordinary 12-inch wafer as an example, the pressure difference during the lifting process can range from 25Torr to 35Torr, and the pressure difference during the wafer removal process can range from 1Torr to 5Torr. When the specifications of the wafer change, the range of the pressure difference will also change adaptively.

[0098] refer to Figure 4In the embodiment of the present application, the first detection element 520, the second detection element 530, the solenoid valve group 540, the air extraction switching valve 322 and the air charging switching valve 312 are all electrically connected to the control element 510 to facilitate signal transmission, wherein the control element 510 may be a host computer, etc. Specifically, the first detection element 520 and the second detection element 530 may transmit the detection information to the industrial computer through the ethercat board in real time, and the industrial computer returns the result to the host computer after conversion, and controls the air charging switching valve 312 or the air extraction switching valve 322 through the DO board. In addition, the industrial computer may also control the solenoid valve group 540 to operate through the ethercat board. It should be noted here that the above-mentioned electrical components and working principles may refer to the relevant technology and will not be elaborated here.

[0099] Based on the above-mentioned needle lifting device and semiconductor process equipment, the embodiment of the present application also discloses a pressure control method, which is applied to the process of placing a wafer and lowering a needle in the semiconductor process equipment. Figures 1 to 7 As shown, the disclosed pressure control method includes:

[0100] During the process of placing the film and lowering the needle, the reaction chamber 110 is slowly evacuated (i.e., roughly evacuated), and the airway 220 is evacuated, and the opening and closing of the air extraction switching valve 322 in the gas delivery component 300 is controlled based on the fuzzy control algorithm, so that the pressure difference between the pressure in the reaction chamber 110 and the pressure in the airway 220 is within a preset range;

[0101] Controlling the multiple ejector pin assemblies 200 of the needle lifting device to descend;

[0102] Controlling the reaction chamber 110 to be quickly evacuated;

[0103] When the pressure in the reaction chamber 110 drops to less than or equal to the first pressure value, the exhaust switching valve 322 is controlled to switch to a fully open state until the pressure in the reaction chamber 110 drops to the pressure control pressure required by the process.

[0104] In the embodiment of the present application, the angle valve 342 can be first switched to the slow pumping valve position, and the vacuum device, such as a dry pump, can be started to slowly vacuumize the reaction chamber 110. In the initial state, the pressure in the reaction chamber 110 can be 735 Torr. During the slow vacuuming process, the pressure in the reaction chamber 110 slowly decreases from 735 Torr. It generally takes about 15 seconds for the pressure to decrease from 735 Torr to 75 Torr.

[0105] In the process of slowly evacuating the reaction chamber 110, in order to prevent the wafer from being separated from the ejector pin assembly 200 due to the low pressure in the reaction chamber 110 and the high pressure in the air channel 220, it is also necessary to evacuate the air channel 220 while slowly evacuating the reaction chamber 110 to ensure that the pressure difference ΔP between the pressure in the air channel 220 and the pressure in the reaction chamber 110 is within a preset range.

[0106] The specific value of the pressure difference ΔP may be set to a preset pressure value P0. When the preset range of the pressure difference ΔP is 25 Torr to 35 Torr, the preset pressure value P0 may be set to 30 Torr.

[0107] Optionally, the opening and closing of the air extraction switching valve 322 is controlled based on a fuzzy control algorithm, including:

[0108] Set the pressure difference and the preset pressure value within the preset range as input quantities;

[0109] Calculate the deviation between the pressure difference and the preset pressure value, and calculate the derivative of the deviation value, and use the deviation value and the derivative of the deviation value as input quantities of fuzzy calculation;

[0110] According to the input of fuzzy calculation and fuzzy PI algorithm, the on-off duty ratio of the air extraction reversing valve is calculated;

[0111] The air extraction switching valve 322 is controlled to open and close based on the on-off duty ratio of the air extraction switching valve 322 .

[0112] Specifically, the deviation value e between the pressure difference ΔP and the preset pressure value P0, as well as the derivative ec of the deviation value e can be calculated, and the deviation value e and the derivative ec of the deviation value e are used as input quantities for fuzzy calculation. Then, the industrial computer can calculate the on-off duty cycle D of the air extraction switching valve 322 based on the input quantity of the fuzzy calculation and the fuzzy PI algorithm, so as to control the opening and closing of the air extraction switching valve 322, thereby ensuring that the pressure difference ΔP is stable around the preset pressure value P0.

[0113] After the pressure difference ΔP stabilizes at a preset pressure value P0 for a period of time (such as 5 seconds), the ejector pin assembly 200 can stably carry the wafer. At this time, the pin lowering operation can be performed; the lower computer cancels the pin raising command of the ejector pin assembly 200 and simultaneously issues the pin lowering command of the ejector pin assembly 200, driving the wafer to descend through the ejector pin assembly 200. The entire pin lowering process lasts about 3 seconds.

[0114] Optionally, after the step of controlling the plurality of ejector pin assemblies 200 of the needle lifting device to descend and before the step of controlling the reaction chamber 110 to be quickly evacuated, the pressure control method further includes:

[0115] Detecting whether the pressure in the reaction chamber 110 drops to less than or equal to the second pressure value within a first time after the slow vacuuming, and whether the plurality of ejector pin assemblies 200 drops to a low position;

[0116] When the pressure in the reaction chamber 110 drops to the second pressure value and the plurality of ejector pin assemblies 200 drop to the low position, the reaction chamber 110 is controlled to be quickly evacuated, otherwise an alarm is thrown.

[0117] Exemplarily, it is detected whether the pressure in the reaction chamber 110 can be reduced to less than or equal to 75 Torr within 20 seconds after slow vacuuming, and whether the low position signals of the plurality of ejector pin assemblies 200 (i.e., the ejector pin assemblies 200 are in a low position) are satisfied. When the pressure in the reaction chamber 110 drops to less than or equal to 75 Torr, and the plurality of ejector pin assemblies 200 all drop to a low position, it indicates that the wafer has been placed on the carrier 120. At this time, the slow vacuuming process is stopped and switched to the fast vacuuming process, so as to perform fast vacuuming on the reaction chamber 110, so that the pressure in the reaction chamber 110 is quickly reduced from 75 Torr to 0.8 Torr, which generally takes about 5 seconds. Based on this, the pressure in the reaction chamber 110 can meet the subsequent process requirements, and it can be ensured that the wafer will not be separated from the carrier 120 during the vacuuming of the reaction chamber 110, thereby ensuring the position accuracy of the wafer. On the contrary, when the pressure in the reaction chamber 110 does not drop to 75 Torr within 20 seconds of slow vacuuming, and / or the ejector assembly 200 is not in a low position, the subsequent process requirements are not met, and an alarm is thrown out to alert the staff.

[0118] In addition, during the rapid vacuuming of the reaction chamber 110, as the pressure in the reaction chamber 110 decreases rapidly, when the pressure in the reaction chamber 110 is less than or equal to 30 Torr, the pressure in the gas channel 220 is less than or equal to 1 Torr; as the pressure in the reaction chamber 110 gradually decreases to less than 30 Torr, the pressure difference ΔP can be guaranteed to be less than 30 Torr at all times, so that even if the fuzzy control algorithm is no longer used to control the opening and closing of the exhaust switching valve 322, the wafer will not be separated from the supporting component 120. Based on this, when the pressure in the reaction chamber 110 is less than or equal to 30 Torr, the exhaust switching valve 322 is no longer controlled by the fuzzy control algorithm, but the exhaust switching valve 322 is directly switched to the fully open state, and the pressure in the gas channel 220 is less than or equal to 1 Torr, and is maintained until the wafer removal and needle lifting process begins, so that the situation of the wafer being blown up due to sudden leakage in the gas channel 220 can be effectively prevented, and the position accuracy of the wafer on the supporting component 120 is guaranteed.

[0119] Optionally, within a second time after the quick vacuuming, it is detected whether the pressure in the reaction chamber 110 is less than the control pressure;

[0120] When the pressure in the reaction chamber 110 is lower than the control pressure, the control stops the quick vacuum pumping, otherwise an alarm is thrown.

[0121] Exemplarily, it is detected whether the pressure in the reaction chamber 110 is less than 0.8 Torr (or other values, which can be set according to the pressure control requirements before the process) within 10 seconds after the fast vacuum pumping. If it is satisfied, the fast vacuum pumping is stopped and the process ends, otherwise an alarm is thrown.

[0122] In one embodiment of the present application, Figure 5 As shown in the figure, the specific process of placing the film and lowering the needle is as follows:

[0123] 1. Switch the angle valve 342 to the slow pumping valve position, and start to slowly pump vacuum on the reaction chamber 110. The pressure in the reaction chamber 110 starts to decrease from the atmospheric pressure of 735 Torr. The pressure difference △P between the pressure in the airway 220 of the ejector assembly 200 and the pressure in the reaction chamber 110 and the deviation value e of the preset pressure value 30 Torr, as well as the derivative ec of the deviation value e are used as the input of the fuzzy calculation. Then, the industrial computer can calculate the on-off duty ratio D value of the air pumping switching valve 322 according to the input of the fuzzy calculation and the fuzzy PI algorithm, so as to control the opening and closing of the air pumping switching valve 322, thereby ensuring that the pressure difference △P is stable at about 30 Torr.

[0124] 2. After waiting for 5 seconds, the ejector assembly 200 can stably carry the wafer, and the needle can be lowered at this time; the lower computer cancels the needle raising command of the ejector assembly 200, and at the same time issues the needle lowering command of the ejector assembly 200 to make the ejector assembly 200 lower. The whole process will last about 3 seconds;

[0125] 3. Check whether the pressure in the reaction chamber 110 is reduced to less than 75 Torr within 20 seconds after switching to the slow extraction valve position and whether the ejector assembly 200 is in the low position; if so, the wafer has been placed on the carrier 120, and the angle valve 342 is switched from the slow extraction valve position to the fast extraction valve position, so that the pressure in the reaction chamber 110 is quickly reduced from 75 Torr to 0.8 Torr. This process generally takes 5 seconds; if not, an alarm is thrown;

[0126] 4. When the pressure in the reaction chamber 110 is less than or equal to 30 Torr, the pressure in the air channel 220 of the ejector assembly 200 is less than 1 Torr. At this time, the fuzzy PI is no longer used to control the air extraction switching valve 322. Instead, the air extraction switching valve 322 is fully opened, and the pressure in the air channel 220 of the ejector assembly 200 is maintained until the wafer removal and needle lifting process begins, so as to prevent the wafer from being blown up due to sudden air leakage in the air channel 220.

[0127] 5. Check whether the pressure in the reaction chamber 110 is less than 0.8 Torr within 10 seconds after the angle valve 342 is switched to the quick-draw valve position. If so, close the quick-draw valve position and the process ends; otherwise, an alarm is issued.

[0128] Based on the above-mentioned needle lifting device and semiconductor process equipment, the embodiment of the present application also discloses a pressure control method, which is applied to the wafer picking and needle lifting process of semiconductor process equipment. Figures 1 to 7 As shown, the disclosed pressure control method includes:

[0129] During the film taking and needle lifting process, the reaction chamber 110 is slowly inflated, and the air channel 220 is stopped from being vacuumed. The opening and closing of the inflation switching valve 312 in the gas delivery component 300 is controlled based on the fuzzy control algorithm, so that the pressure difference between the pressure in the reaction chamber 110 and the pressure in the air channel 220 is within a preset range;

[0130] Controlling the multiple ejector pin assemblies 200 of the needle lifting device to rise;

[0131] Controlling the rapid inflation of the reaction chamber 110;

[0132] When the pressure in the reaction chamber 110 increases to the third pressure value, the inflation switching valve 312 is controlled to switch to a fully open state until the pressure in the reaction chamber 110 increases to the film taking pressure.

[0133] In the embodiment of the present application, the slow filling valve 332 can be opened first to gradually increase the pressure in the reaction chamber 110. It should be noted here that after the process is completed, the reaction chamber 110 has a certain degree of vacuum. At this time, the reaction chamber 110 can be slowly filled with gas to increase the pressure in the reaction chamber 110 to a pressure value that can be used to take the film. In addition, during the process of slowly filling the reaction chamber 110, the airway 220 is stopped from being vacuumed so that the pressure difference ΔP between the pressure in the airway 220 and the pressure in the reaction chamber 110 is within a preset range.

[0134] The specific value of the pressure difference ΔP may be set to a preset pressure value P0. When the preset range of the pressure difference ΔP is 25 Torr to 35 Torr, the preset pressure value P0 may be set to 30 Torr.

[0135] Optionally, the opening and closing of the inflation switching valve 312 is controlled based on a fuzzy control algorithm, including:

[0136] The set pressure difference and the preset pressure value within the preset range are input quantities;

[0137] Calculate the deviation between the pressure difference and the preset pressure value, and calculate the derivative of the deviation value, and use the deviation value and the derivative of the deviation value as input quantities of fuzzy calculation;

[0138] The on-off duty ratio of the inflation switching valve 312 is calculated according to the input of the fuzzy calculation and the fuzzy PI algorithm;

[0139] The charging switching valve 312 is opened and closed based on the on-off duty ratio of the charging switching valve 312 .

[0140] Specifically, the deviation value e between the pressure difference ΔP and the preset pressure value P0, as well as the derivative ec of the deviation value e can be calculated, and the deviation value e and the derivative ec of the deviation value e are used as the input of the fuzzy calculation. Then, the industrial computer can calculate the on-off duty cycle D of the inflation switching valve 312 based on the input of the fuzzy calculation and the fuzzy PI algorithm, so as to control the opening and closing of the inflation switching valve 312, thereby ensuring that the pressure difference ΔP is stable around the preset pressure value P0.

[0141] After the pressure difference ΔP stabilizes at a preset pressure value P0 for a period of time (such as 5 seconds), the lower computer cancels the needle lowering command of the ejector assembly 200, and simultaneously issues a needle raising command of the ejector assembly 200, driving the wafer to rise through the ejector assembly 200. The entire needle raising process will last for 3 seconds.

[0142] Optionally, after the step of controlling the multiple ejector pin assemblies 200 of the needle lifting device to rise, and before the step of controlling the reaction chamber 110 to be quickly inflated, the pressure control method further includes:

[0143] Detecting whether the pressure in the reaction chamber 110 rises to a value greater than or equal to a fourth pressure value within a third time after the slow inflation, and whether the plurality of ejector pin assemblies 200 rise to a high position;

[0144] When the pressure in the reaction chamber 110 rises to a fourth pressure value and the plurality of ejector pin assemblies 200 rise to a high position, the reaction chamber 110 is controlled to be quickly inflated, otherwise an alarm is triggered.

[0145] Exemplarily, it is detected whether the pressure in the reaction chamber 110 can be increased to greater than or equal to 75 Torr within 20 seconds after the slow filling valve 332 is opened, and at the same time, whether the high position signals of the multiple ejector assemblies 200 (i.e., the ejector assemblies 200 are in a high position) are satisfied. When the pressure in the reaction chamber 110 rises to greater than or equal to 75 Torr, and the multiple ejector assemblies 200 all rise to a high position, the slow filling valve 332 is closed, the fast filling valve 333 is opened, and the fast filling process is switched to facilitate the fast filling of the reaction chamber 110, so that the pressure in the reaction chamber 110 is rapidly increased. On the contrary, when the pressure in the reaction chamber 110 does not rise to 75 Torr within 20 seconds after the slow filling valve 332 is opened, and / or the ejector assembly 200 is not in a high position, the film taking requirement is not met, and an alarm is thrown out at this time to avoid the occurrence of damage to the experience during the film taking process.

[0146] In addition, during the fast inflation process of the reaction chamber 110, as the pressure in the reaction chamber 110 increases rapidly, when the pressure in the reaction chamber 110 reaches 730 Torr (at this time, the pressure is 5 Torr away from the atmospheric pressure of 735 Torr), the pressure in the airway 220 of the ejector assembly 200 is 700 Torr. During the aforementioned fast inflation process, the opening and closing of the inflation switching valve 312 is controlled by the fuzzy control algorithm; after this, the inflation is no longer controlled by the fuzzy control algorithm. Instead of switching valve 312, the inflation switching valve 312 is directly switched to the fully open state, so that the pressure in the airway 220 of the ejector assembly 200 is quickly increased from 700Torr to about 730Torr. At this time, the pressure in the reaction chamber 110 is simultaneously increased from 700Torr to 735Torr. Then, the inflation switching valve 312 is closed, so that the pressure difference between the pressure in the airway 220 of the ejector assembly 200 and the pressure in the reaction chamber 110 is about 1 to 5Torr. It should be noted here that when the robot takes the wafer, the pressure in the airway 220 of the ejector assembly 200 is slightly lower than the pressure in the reaction chamber 110, and the pressure difference is about 1 to 5Torr, so that the ejector assembly 200 can have a smaller adsorption force on the wafer. In this way, the robot can take the wafer away by relying on the lifting force of the robot on the wafer.

[0147] Optionally, within a fourth time after the fast inflation, it is detected whether the pressure in the reaction chamber 110 is greater than the film removal pressure;

[0148] When the pressure in the reaction chamber 110 is greater than the film taking pressure, the control stops the fast inflation, otherwise an alarm is thrown.

[0149] Exemplarily, it is detected whether the pressure in the reaction chamber 110 is greater than 735 Torr (or other values) within 15 seconds after the fast filling valve 333 is opened. If satisfied, the fast filling valve 333 is closed and the process ends, otherwise an alarm is thrown.

[0150] In the present application embodiment, Figure 6 As shown in the figure, the specific process of taking the film and lifting the needle is as follows:

[0151] 1. Open the slow filling valve 332 and close the air extraction switching valve 322. At this time, the pressure in the reaction chamber 110 begins to rise. The pressure difference △P between the pressure in the airway 220 of the ejector assembly 200 and the pressure in the reaction chamber 110 and the deviation value e of the preset pressure value 30Torr, as well as the derivative ec of the deviation value e are the input quantities of the fuzzy calculation. Then, the industrial computer can calculate the on-off duty ratio D value of the inflation switching valve 312 according to the input quantity of the fuzzy calculation and the fuzzy PI algorithm, so as to control the opening and closing of the inflation switching valve 312, thereby ensuring that the pressure difference △P is stable at about 30Torr, that is, ensuring that the pressure in the airway 220 of the ejector assembly 200 is less than the pressure in the reaction chamber 110, and the pressure difference is about 30Torr;

[0152] 2. After waiting for 5 seconds, the lower computer cancels the needle lowering command of the ejector assembly 200 and issues the needle raising command of the ejector assembly 200 to make the ejector assembly 200 rise. The whole process will last for 3 seconds.

[0153] 3. Detect whether the pressure in the reaction chamber 110 rises to greater than or equal to 75 Torr within 20 seconds after the slow filling valve 332 is opened and whether the ejector assembly 200 is in a high position; if so, the ejector assembly 200 is already in a high position, close the slow filling valve 332, open the fast filling valve 333, and quickly fill the reaction chamber 110; if not, throw an alarm;

[0154] 4. When the pressure in the reaction chamber 110 reaches 730 Torr (at this time, the pressure is 5 Torr away from the atmospheric pressure of 735 Torr), the pressure in the air passage 220 of the ejector assembly 200 is less than 700 Torr. At this time, the fuzzy PI control of the inflation switching valve 312 is no longer used, but the inflation switching valve 312 is fully opened, and the pressure in the air passage 220 of the ejector assembly 200 is rapidly increased from 700 Torr to about 730 Torr (at this time, the pressure in the reaction chamber 110 is simultaneously increased from 700 Torr to 735 Torr), and then the inflation switching valve 312 is closed, so that the pressure difference between the pressure in the air passage 220 of the ejector assembly 200 and the pressure in the reaction chamber 110 is about 1 to 5 Torr;

[0155] 5. Check whether the pressure in the reaction chamber 110 is greater than 735 Torr within 15 seconds after the fast filling valve 333 is opened. If so, close the fast filling valve 333 and the process ends; otherwise, an alarm is issued.

[0156] In addition, the embodiment of the present application is based on a fuzzy PI algorithm of fuzzy control to ensure that the pressure difference between the pressure in the airway 220 of the ejector assembly 200 and the pressure in the reaction chamber 110 is stable. The specific algorithm is as follows:

[0157] 1. Select the observed quantity and the controlled quantity: select the deviation value e between the pressure difference △P and the set value of the preset pressure value P0 (such as 30Torr, etc.) as the observed quantity, select the on-off duty ratio D of the exhaust switching valve 322 as the controlled quantity during the needle lowering vacuum process, or select the on-off duty ratio D of the inflation switching valve 312 as the controlled quantity during the needle raising inflation process.

[0158] 2. Quantification of input quantity: The deviation value e and its derivative ec are quantified in a linear manner. The functional relationship is as follows:

[0159]

[0160] 3. Fuzzification of input values: Select the fuzzy subsets of the deviation value e and its derivative ec. For the PI controller, seven linguistic variables, such as negative large [NB], negative medium [NM], negative small [NS], zero [ZO], positive small [PS], positive medium [PM], and positive large [PB], are used to express the fuzzy subsets. The triangular membership function is used to establish the membership of the deviation value e and its derivative ec on the fuzzy subsets, such as Figure 7 shown.

[0161] 4. Establish fuzzy rule table

[0162] The Kp fuzzy rule is as follows (Kp is the proportional term coefficient in the PI algorithm):

[0163]

[0164] The Ki fuzzy rule is as follows (Ki is the integral term coefficient in the PI algorithm):

[0165]

[0166] 5. Defuzzification:

[0167] In the previous example, the triangular membership function was used, and the same quantitative target was used, so at a certain moment, the membership of the fuzzy variables where the input and output are located is the same; the centroid method is used to calculate the quantitative value of each output. Therefore, the calculation formulas for Kp and Ki are the same, as follows:

[0168]

[0169] Among them, M is the membership degree, and F is the fuzzy quantization value (see fuzzy rule table)

[0170] Substitute M and F of Kp and Ki into the above formulas to obtain the respective values ​​of Kp and Ki.

[0171] 6. Substitute the obtained Kp and Ki into the formula to obtain the on-off duty ratio of the inflation switching valve 312 or the exhaust switching valve 322:

[0172]

[0173] Therefore, the on-off duty ratio of the inflation switching valve 312 or the exhaust switching valve 322 can be controlled to meet the needs under actual working conditions.

[0174] To summarize, the embodiment of the present application realizes the parallel processing of the vacuuming and needle lifting processes of the process chamber 100, shortens the time consumption of the needle lifting, and can increase the number of wafers per hour (WPH) of the equipment; the wafer can be adsorbed during the needle lowering process to prevent the wafer from sliding due to the air cushion effect when it contacts the supporting component 120, effectively avoiding the problem of excessive particles in the process chamber 100; in addition, the present application also solves the problem of wafer sticking due to excessive vacuum adsorption force, and realizes precise control of the vacuum adsorption force of the ejector pin 210.

[0175] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A needle lifting device, characterized in that: include: A pin assembly (200) for lifting and lowering a wafer, and a gas delivery assembly (300); The ejector pin assembly (200) has an air channel (220), a first end of the air channel (220) being used for contacting a wafer, a second end of the air channel (220) being connected to a gas delivery end of the gas delivery assembly (300), and the gas delivery assembly (300) being used for inflating the air channel (220) and / or extracting air from the air channel (220).

2. The needle lifting device according to claim 1, characterized in that: The gas delivery component (300) comprises a first gas charging path (310) and a first gas extraction path (320); The needle lifting device also includes an air box (400), the air box (400) is provided with an airway interface (410), an inflation interface (420) and an exhaust interface (430), the second end of the airway (220) is connected to the airway interface (410), the first inflation path (310) is connected to the inflation interface (420), and the first exhaust path (320) is connected to the exhaust interface (430).

3. The needle lifting device according to claim 2, characterized in that: The first inflation path (310) comprises a first inflation pipeline (311) and an inflation switching valve (312), one end of the first inflation pipeline (311) is connected to the inflation interface (420), the other end of the first inflation pipeline (311) is used for inputting gas, and the inflation switching valve (312) is arranged on the first inflation pipeline (311); And / or, the first air extraction path (320) includes a first air extraction pipeline (321) and an air extraction switching valve (322), one end of the first air extraction pipeline (321) is connected to the air extraction interface (430), the other end of the first air extraction pipeline (321) is used to output gas, and the air extraction switching valve (322) is arranged on the first air extraction pipeline (321).

4. The needle lifting device according to claim 3, characterized in that: The first inflation pipeline (311) is further provided with a throttle valve (313), and the throttle valve (313) is located downstream of the inflation switching valve (312) along the inflation direction; The first air extraction pipeline (321) is further provided with a one-way valve (323), and the one-way valve (323) is located downstream of the air extraction switching valve (322) along the air extraction direction.

5. A semiconductor process equipment, characterized in that: include: A process chamber (100), a control system (500), and a needle lift device as claimed in any one of claims 1 to 4; The process chamber (100) comprises a reaction chamber (110) and a carrying component (120), wherein the carrying component (120) is arranged in the reaction chamber (110) and is used to carry a wafer; The needle lifting device comprises a plurality of ejector pin assemblies (200), each of the ejector pin assemblies (200) comprises an ejector pin (210), the ejector pins (210) of the plurality of ejector pin assemblies (200) are respectively liftable and pass through the bearing component (120), and the air passage (220) at least passes through the ejector pin (210); The gas delivery component (300) is in communication with the reaction chamber (110) and the gas channel (220) respectively; The control system (500) comprises a control element (510) and a first detection element (520) and a second detection element (530) electrically connected to the control element (510), respectively; the first detection element (520) is used to detect the pressure in the reaction chamber (110); the second detection element (530) is used to detect the pressure in the airway (220); the control element (510) is used to control the gas delivery component (300) according to the pressure difference between the pressures detected by the first detection element (520) and the second detection element (530), so as to adjust the pressure difference through the gas delivery component (300) so that the pressure difference is within a preset range.

6. The semiconductor process equipment according to claim 5, characterized in that: The gas delivery component (300) further comprises a second gas filling path (330), one end of the second gas filling path (330) is connected to the reaction chamber (110), and the other end of the second gas filling path (330) is used for inputting gas; And / or, the gas delivery component (300) further comprises a second gas extraction path (340), one end of the second gas extraction path (340) is connected to the reaction chamber (110), and the other end of the second gas extraction path (340) is used for outputting gas.

7. The semiconductor process equipment according to claim 6, characterized in that: The second inflation path (330) comprises a second inflation pipeline (331), a slow inflation valve (332) and a fast inflation valve (333); The second gas-charging pipeline (331) is connected to the reaction chamber (110), and the second gas-charging pipeline (331) comprises a first gas-charging branch (3311) and a second gas-charging branch (3312) connected in parallel with each other, the slow-charging valve (332) is arranged on the first gas-charging branch (3311), and the fast-charging valve (333) is arranged on the second gas-charging branch (3312).

8. The semiconductor process equipment according to claim 7, characterized in that: The control system (500) further comprises a solenoid valve group (540), wherein the solenoid valve group (540) is electrically connected to the control element (510), and is electrically connected to the slow filling valve (332) and the fast filling valve (333), respectively, and is used for switching the respective states of the slow filling valve (332) and the fast filling valve (333) under the control of the control element (510).

9. The semiconductor process equipment according to claim 6, characterized in that: The second air extraction path (340) comprises a second air extraction pipeline (341) and an angle valve (342) provided on the second air extraction pipeline (341), wherein the angle valve (342) has a slow extraction valve position and a fast extraction valve position; The second exhaust pipeline (341) is connected to the reaction chamber (110); The control system (500) further comprises a solenoid valve group (540), wherein the solenoid valve group (540) is electrically connected to the control element (510) and to the angle valve (342), and is used for switching the state of the angle valve (342) under the control of the control element (510).

10. The semiconductor process equipment according to claim 5, characterized in that: The first detection element (520) and the second detection element (530) are both pressure sensors; And / or, the first detection element (520) is disposed in the reaction chamber (110), and the second detection element (530) is disposed in the air box (400) included in the needle lifting device.

11. The semiconductor process equipment according to claim 5, characterized in that: When the wafer is lifted and lowered by the lifting needle device, the pressure difference ranges from 25 Torr to 35 Torr; Alternatively, when the wafer is removed from the lifting pin device, the pressure difference ranges from 1 Torr to 5 Torr.

12. A pressure control method, applied to the process of lowering the needle during wafer placement or raising the needle during wafer removal in semiconductor process equipment, characterized in that: The pressure control method comprises: During the film placement and needle lowering process: The reaction chamber (110) is slowly evacuated, and the gas passage (220) is evacuated, and the opening and closing of the gas extraction switching valve (322) in the gas delivery component (300) is controlled based on a fuzzy control algorithm, so that the pressure difference between the pressure in the reaction chamber (110) and the pressure in the gas passage (220) is within a preset range; Controlling the plural ejector pin assemblies (200) of the needle lifting device to descend; Controlling the reaction chamber (110) to be quickly evacuated; When the pressure in the reaction chamber (110) drops to less than or equal to the first pressure value, the air extraction switching valve (322) is controlled to switch to a fully open state until the pressure in the reaction chamber (110) drops to a pressure control pressure required by the process; During the film removal and needle lifting process: The reaction chamber (110) is slowly inflated, and the air passage (220) is stopped from being vacuumed, and the opening and closing of the inflation switching valve (312) in the air delivery component (300) is controlled based on a fuzzy control algorithm, so that the pressure difference between the pressure in the reaction chamber (110) and the pressure in the air passage (220) is within a preset range; Controlling the rise of multiple ejector pin assemblies (200) of the needle lifting device; Controlling the rapid inflation of the reaction chamber (110); When the pressure in the reaction chamber (110) rises to a third pressure value, the inflation switching valve (312) is controlled to switch to a fully open state until the pressure in the reaction chamber (110) rises to a film taking pressure.

13. The pressure control method according to claim 12, characterized in that: Controlling the opening and closing of the air extraction switching valve (322) or the air charging switching valve (312) based on the fuzzy control algorithm comprises: Setting the pressure difference and the preset pressure value within the preset range as input quantities; Calculating a deviation between the pressure difference and the preset pressure value, and calculating a derivative of the deviation value, and using the deviation value and the derivative of the deviation value as inputs of fuzzy calculation; Calculating the on-off duty ratio of the air extraction switching valve (322) or the air charging switching valve (312) according to the input quantity of the fuzzy calculation and the fuzzy PI algorithm; The air extraction switching valve (322) is controlled to open and close based on the on-off duty ratio of the air extraction switching valve (322), or the air charging switching valve (312) is controlled to open and close based on the on-off duty ratio of the air charging switching valve (312).

14. The pressure control method according to claim 12, characterized in that: After the step of controlling the descent of the plurality of ejector pin assemblies (200) of the needle lifting device and before the step of controlling the rapid vacuuming of the reaction chamber (110), the pressure control method further comprises: Detecting whether the pressure in the reaction chamber (110) drops to less than or equal to a second pressure value within a first time after slow vacuuming, and whether the plurality of ejector pin assemblies (200) drop to a low position; When the pressure in the reaction chamber (110) drops to the second pressure value and the plurality of ejector pin assemblies (200) drop to a low position, the reaction chamber (110) is controlled to be quickly evacuated, otherwise an alarm is triggered; or, After the step of controlling the multiple ejector pin assemblies (200) of the needle lifting device to rise, and before the step of controlling the reaction chamber (110) to be quickly inflated, the pressure control method further comprises: detecting whether the pressure in the reaction chamber (110) rises to a value greater than or equal to a fourth pressure value within a third time after the slow inflation, and whether the plurality of ejector pin assemblies (200) rise to a high position; When the pressure in the reaction chamber (110) rises to the fourth pressure value and the plurality of ejector pin assemblies (200) rise to a high position, the reaction chamber (110) is controlled to be quickly inflated, otherwise an alarm is triggered.

15. The pressure control method according to claim 12, characterized in that: Within a second time after the quick vacuuming is performed, detecting whether the pressure in the reaction chamber (110) is less than the pressure control pressure; When the pressure in the reaction chamber (110) is lower than the pressure control pressure, the quick vacuum pumping is stopped, otherwise an alarm is issued; or, Within a fourth time after the rapid inflation, detecting whether the pressure in the reaction chamber (110) is greater than the film taking pressure; When the pressure in the reaction chamber (110) is greater than the film taking pressure, the fast inflation is stopped, otherwise an alarm is triggered.

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