pneumatic control system for semiconductor equipment and semiconductor equipment

Abstract

This invention discloses a gas path control system for a semiconductor device and the semiconductor device itself. The gas path control system includes a vacuum gas path system, which comprises a main vacuum gas path, vacuum load units, branch paths, and a pressure control component. The main vacuum gas path is connected to a vacuum source. At least two vacuum load units are used to perform wafer adsorption operations. A branch path is configured one-to-one with a vacuum load unit, and each vacuum load unit is connected to the end of its corresponding branch path. The pressure control component is located upstream of the adsorption surface of each vacuum load unit. When the load end of a vacuum load unit is in an unloaded state, the gas path is closed. When the load end is in an adsorption state, the gas path is open. Therefore, this invention can prevent a sudden drop in vacuum pressure within the vacuum gas path from affecting the adsorption pressure values ​​of other vacuum load units, reducing the frequency of device alarms.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing equipment technology, and more specifically to a pneumatic control system for semiconductor equipment and semiconductor equipment. Background Technology

[0002] In semiconductor equipment, various gases and working environments are often required by the plant system to achieve specific functions or meet performance requirements, with compressed air and vacuum being the most common. For example, in the front-end module (EFEM), the handling robots and pre-aligners responsible for wafer carrying, transporting, and pre-aligning rely on vacuum to hold the wafers in place. Similarly, the chucks used to hold wafers in the mainframe module also require vacuum to ensure wafer stability. Furthermore, some air-bearing motion stages require compressed air to form an air film for frictionless movement or to purge and cool heat-generating components. Therefore, a well-designed airflow system is essential to meet these diverse needs.

[0003] In existing technologies, vacuum circuit designs are typically quite simple: a single vacuum line is drawn directly from the plant's air supply, split into multiple branches via a splitter, each connected to a unit requiring vacuum. Each branch is usually equipped with a manual pressure-reducing valve to regulate the vacuum pressure and a solenoid valve to control the flow of air. However, this structure has significant shortcomings in practical applications. When multiple units using vacuum simultaneously activate their solenoid valves, the instantaneous increase in airflow can cause a sudden drop in vacuum pressure. If the vacuum pressure falls below the range required for wafer adsorption, the equipment will trigger an alarm and shut down, impacting production efficiency. Furthermore, for equipment with high requirements for wafer adsorption positioning accuracy and repeatability, even small pressure fluctuations within the allowable range can alter the adhesion between the wafer and the chuck, affecting the accuracy and stability of subsequent measurements, inspections, or processing. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a gas path control system for a semiconductor device and a semiconductor device, so as to avoid the sudden drop in vacuum pressure in the vacuum path from affecting the adsorption pressure value of other vacuum load units.

[0005] To achieve the above and other related objectives, the present invention provides a pneumatic control system for a semiconductor device. The pneumatic control system includes a vacuum pneumatic system, which includes:

[0006] The main vacuum circuit is connected to the vacuum source;

[0007] At least two vacuum load units are used to perform wafer adsorption operations;

[0008] There are at least two branches, and each branch is set up in a one-to-one correspondence with a vacuum load unit. Each vacuum load unit is connected to the end of the corresponding branch.

[0009] The pressure control component is located upstream of the adsorption surface of each vacuum load unit. When the load end of the vacuum load unit is in an unloaded state, the pressure control component controls the vacuum to be cut off to maintain the upstream vacuum pressure. When the load end is in an adsorption state, the pressure control component controls the vacuum to be opened to establish an adsorption path from the vacuum source to the load end.

[0010] Optionally, the pressure control component is a vacuum logic valve. When the load end of the vacuum load unit is in an unloaded state, the high-speed airflow generated by the vacuum source drives the valve core to operate, thereby cutting off the air path and maintaining the upstream vacuum pressure. When the load end is in an adsorption state, the airflow stops, and the valve core automatically opens under the action of the reset element, establishing an adsorption path from the vacuum source to the load end.

[0011] Optionally, the vacuum air path system also includes:

[0012] The main on / off valve is located in the main vacuum circuit and is used to control the on / off state of the main vacuum circuit.

[0013] Optionally, the vacuum air path system also includes:

[0014] Pressure regulating valves, located in the main vacuum circuit and / or each branch circuit, are used to regulate the vacuum pressure in the air circuit.

[0015] Optionally, the vacuum air path system also includes:

[0016] The buffer gas storage tank is located in the main vacuum circuit and downstream of the main on / off valve. It is used to store vacuum when the main on / off valve is open and to release vacuum when the vacuum load unit is turned on to suppress pressure fluctuations.

[0017] Optionally, the vacuum air path system also includes:

[0018] A pressure sensor is installed between the buffer gas tank and the vacuum load unit to detect the actual vacuum pressure supplied to the vacuum load unit in real time.

[0019] Alternatively, the vacuum load unit may be one of a handling arm, a pre-alignment unit, or a wafer chuck.

[0020] Optionally, the air path control system further includes a compressed air path system, which includes:

[0021] The main compressed air circuit is connected to the air source.

[0022] At least one air flotation structure;

[0023] At least one vacuum load unit is used to perform wafer adsorption operations;

[0024] Each compressed air branch is configured in a corresponding manner with the air flotation structure and the vacuum load unit, with the air flotation structure and the vacuum load unit respectively located at the end of the corresponding branch.

[0025] The vacuum generating unit is located on the compressed air branch where the vacuum load unit is located, and is located upstream of the vacuum load unit. It is used to convert the input air into vacuum gas to drive the vacuum load unit to work.

[0026] Optionally, the compressed air path system includes:

[0027] The shut-off valve is installed in the main compressed air circuit and is used to control the opening and closing of the main vacuum circuit.

[0028] Optionally, the compressed air path system also includes:

[0029] The pneumatic assembly is located on the main compressed air line and downstream of the shut-off valve; the pneumatic assembly includes an air filter, an oil mist separator, and a pressure regulating valve.

[0030] Optionally, the compressed air path system also includes:

[0031] The vacuum breaking unit is located in the compressed air branch and is connected in parallel with the vacuum generating unit upstream of the vacuum load unit;

[0032] The controller is configured to: after the vacuum load unit completes the process and cuts off the main compressed air path, control the vacuum breaking unit to open and introduce air into the vacuum load unit to eliminate the residual vacuum.

[0033] Optionally, the vacuum breaking unit includes:

[0034] A two-position three-way valve includes a first output terminal and a second output terminal, with the first output terminal connected to a vacuum generating unit;

[0035] The vacuum breaking branch has its inlet end connected to the second output end and its outlet end connected to the vacuum load unit.

[0036] Optionally, the vacuum breaking unit further includes:

[0037] A flow rate control valve, located on the vacuum breaking branch, is used to control the gas pressure to eliminate residual vacuum.

[0038] According to one aspect of the present invention, a semiconductor device is also provided, including the above-described pneumatic control system for the semiconductor device.

[0039] Compared with the prior art, the pneumatic control system and semiconductor device of the present invention have at least the following beneficial effects:

[0040] The gas path control system for semiconductor equipment of this invention includes a vacuum gas path system, comprising a main vacuum gas path, at least two vacuum load units, at least two branches, and a pressure control component. The main vacuum gas path is connected to a vacuum source. The at least two vacuum load units are used to perform wafer adsorption operations. Each branch corresponds to one vacuum load unit, and each vacuum load unit is connected to the end of its corresponding branch. The pressure control component is located upstream of the adsorption surface of each vacuum load unit. When the load end of a vacuum load unit is in an unloaded state, the pressure control component controls the vacuum to be cut off to maintain the upstream vacuum pressure; when the load end is in an adsorption state, the pressure control component controls the vacuum to be opened to establish an adsorption path from the vacuum source to the load end. Therefore, this invention can ensure that when the vacuum load unit is open to the atmosphere (unloaded state), the valve is closed, maintaining the vacuum pressure within the vacuum gas path, preventing a sudden drop in vacuum pressure within the vacuum gas path from affecting the adsorption pressure values ​​of other vacuum load units, reducing equipment alarm frequency, and improving working efficiency.

[0041] The pneumatic control system for semiconductor equipment of this invention includes a compressed air pneumatic system. At least one vacuum load unit is connected to the compressed air pneumatic system, and a vacuum generator is installed in the pneumatic structure to achieve vacuum load. This alleviates the heavy load on the vacuum pneumatic system and the instability of vacuum adsorption, avoiding alarms and shutdowns caused by fluctuations in equipment vacuum pressure. Simultaneously, the vacuum pressure generated by the vacuum generator ensures repeatability and stability, which is beneficial to the accuracy and stability of measurement results or price processing procedures in various semiconductor equipment.

[0042] The semiconductor device of the present invention includes the above-described gas path control system and similarly possesses the above-described technical effects. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the vacuum air circuit system in the air circuit control system of an embodiment of the present invention;

[0044] Figure 2 This is a schematic diagram of the compressed air circuit system in the air circuit control system of an embodiment of the present invention;

[0045] Figure 3 This is a schematic diagram of the compressed air circuit system in the air circuit control system of an embodiment of the present invention.

[0046] Illustration of reference numerals in the attached diagram:

[0047] 10. Vacuum circuit system; 11. Main vacuum circuit; 111. Main on / off valve; 112. Main pressure regulating valve; 113. First buffer gas storage tank; 114. First check valve; 12. Branch pressure regulating valve; 131. First branch; 132. Second branch; 133. Third branch; 14. First two-position three-way valve; 15. Pressure sensor; 16. Pressure control assembly; 17. First vacuum load unit; 18. Second vacuum load unit; 19. Third vacuum load unit.

[0048] 20. Compressed air circuit system; 21. Main compressed air circuit; 211. Shut-off valve; 212. Pneumatic components; 2121. Air filter; 2122. Oil mist separator; 2123. Pressure regulating valve; 213. Second check valve; 214. Second buffer outlet tank; 22. First compressed air branch; 221. First pressure regulating valve; 222. Normally open solenoid valve; 223. Air flotation structure; 23. Second compressed air branch; 231. Second pressure regulating valve; 232. Normally closed solenoid valve; 233. Vacuum generating unit; 2331. Vacuum generator; 2332. Filter; 2333. Silencer; 234. Fourth vacuum load unit; 241. Second two-position three-way valve; 242. Vacuum breaking branch; 243. Flow rate control valve. Detailed Implementation

[0049] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application. It should be noted that, unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0050] It should be understood that the illustrations provided in the embodiments of this invention are merely schematic representations of the basic concept of the invention. Although the illustrations only show components relevant to the invention and are not drawn according to the actual number, shape, and size of components in implementation, the shape, quantity, and proportion of each component can be arbitrarily changed in actual implementation, and the component layout may also be more complex. The structures, proportions, sizes, etc., shown in the accompanying drawings are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationships, or adjustments to the size, without affecting the effects and objectives that the invention can produce, should still fall within the scope of the technical content disclosed in this application.

[0051] Example 1

[0052] This embodiment provides a gas path control system for a semiconductor device, which includes a vacuum gas path system. (Refer to...) Figure 1 The vacuum circuit system includes a main vacuum circuit 11, at least two vacuum load units, at least two branch circuits, and a pressure control component 16.

[0053] The main vacuum path 11 is connected to a vacuum source. In this embodiment, the vacuum source is a plant vacuum source. One end of the main vacuum path 11 is connected to the plant vacuum source, and the other end is provided with multiple branches, each branch connecting to a vacuum load unit. The main vacuum path 11 is used to introduce the vacuum in the plant vacuum source into each vacuum load unit through the branches.

[0054] A vacuum load unit is used to perform wafer pick-up operations. Optionally, the vacuum load unit can be one of a handling arm, a pre-alignment unit, or a wafer chuck. Optionally, the vacuum path system includes at least two vacuum load units, with branches corresponding one-to-one with each vacuum load unit to supply gas to each vacuum load unit. In this embodiment, the vacuum path system includes three vacuum load units: a first vacuum load unit 17, a second vacuum load unit 18, and a third vacuum load unit 19. The first vacuum load unit 17 and the second vacuum load unit 18 are robotic arms for handling wafers, and the third vacuum load unit 19 is a pre-alignment unit. Of course, in other embodiments, more vacuum load units may be included, and wafer chucks may also be provided in the vacuum load units. This embodiment does not limit the number or type of vacuum load units.

[0055] Because the vacuum source in the vacuum circuit system is configured as a multi-branch system, when two or more vacuum-using load units simultaneously open their air circuit valves—for example, when the pre-aligner opens its vacuum to prepare for wafer adsorption, and the wafer chuck also opens its vacuum to prepare for wafer adsorption—the ends of two vacuum circuits are connected to the atmosphere. This can cause a sudden drop in vacuum pressure, which may not meet the pressure range required for the pre-aligner or wafer chuck to adsorb the wafer, leading to equipment alarms and shutdowns, affecting normal machine operation. Furthermore, even small fluctuations in vacuum pressure can cause minute displacement of the adsorbed wafer for equipment requiring high adsorption or positioning accuracy, thus affecting the accuracy and stability of subsequent quantity measurement or processing.

[0056] To address the aforementioned technical issues, this embodiment includes a pressure control component 16 upstream of each vacuum load unit. When the load end of the vacuum load unit is in an unloaded state, the pressure control component controls the vacuum supply to the vacuum load unit to cut off, maintaining the upstream vacuum pressure. When the load end is in an adsorption state, the pressure control component controls the vacuum supply to the vacuum load unit to open, establishing an adsorption path from the vacuum source to the load end. That is, it can effectively suppress a sudden drop in vacuum pressure even if the downstream vacuum load unit is in a vacuum state but no wafer is adsorbed. Therefore, this embodiment ensures that when the vacuum load unit is connected to the atmosphere (unloaded state), the gas path is closed, maintaining the vacuum pressure within the vacuum path and preventing a sudden drop in vacuum pressure within the vacuum path from affecting the adsorption pressure values ​​of other vacuum load units, reducing equipment alarm frequency, and improving working efficiency.

[0057] When the load end of the vacuum load unit is in an unloaded state, the high-speed airflow generated by the vacuum source drives the valve core to operate, cutting off the air path to maintain the upstream vacuum pressure. When the load end is in an adsorption state, the airflow stops, and the valve core automatically opens under the action of the reset element, establishing an adsorption path from the vacuum source to the load end. In this embodiment, the pressure control component 16 is a vacuum logic valve, which achieves valve closure or opening through vacuum pressure or internal spring force. When no wafer is adsorbed, the unobstructed vacuum airflow compresses the internal spring, closing the valve to suppress a sudden drop in vacuum pressure. When a wafer is adsorbed, the vacuum airflow reduces the spring extension, and the spring force partially opens the valve, thereby achieving the effect of adsorbing the wafer. Optionally, the vacuum logic valve is a vacuum logic valve with a filter. In other embodiments, the pressure control component 16 can also integrate a valve core with a spring in the air outlet of the vacuum load unit. When the suction cup is not in contact with the wafer, the air outlet is open. After the vacuum is turned on, the pressure difference above and below the valve core will overcome the spring force, sucking the valve core down, thereby automatically blocking the air outlet and preventing air leakage and pressure drop. When the wafer is being held, it covers the vent, eliminating the pressure difference. A spring lifts the valve core, opening the air path and allowing the suction cup to begin normally adsorbing the wafer. Optionally, the pressure control assembly may include a controller, an on / off valve, and a sensor. The on / off valve is located upstream of the vacuum load unit, and a sensor is installed on the vacuum load unit. When the sensor detects a workpiece on the vacuum load unit, it sends a signal to the controller to open the on / off valve, opening the air path. When no wafer is detected, the controller receives the signal and closes the on / off valve in the air path to prevent a sudden drop in vacuum pressure due to air leakage during no-load conditions.

[0058] Optionally, the vacuum circuit system also includes a main on / off valve 111, which is installed on the main vacuum circuit 11 and used to control the on / off of the main vacuum circuit 11. Optionally, the main on / off valve 111 is a manual shut-off valve, which can be used to cut off the plant gas supply during maintenance or repair.

[0059] Optionally, the vacuum circuit system further includes pressure regulating valves, which are disposed in the main vacuum circuit 11 and / or each branch circuit, for regulating the pressure in the circuit. In this embodiment, the pressure regulating valves include a main circuit pressure regulating valve 11 and a branch circuit pressure regulating valve 12, which are used to regulate the pressure in the main vacuum circuit 11 and the branch circuit, respectively. The main circuit pressure regulating valve 11 is located downstream of the main on / off valve 111.

[0060] Optionally, the vacuum circuit system further includes a buffer storage tank, defined as a first buffer storage tank 113, which is disposed in the main vacuum circuit 11 and downstream of the main on / off valve 111. This buffer storage tank stores vacuum when the main on / off valve 111 is open and releases vacuum to suppress pressure fluctuations when the vacuum load unit is activated. Optionally, a first check valve 114 is also disposed downstream of the first buffer storage tank 113. This first check valve 114 prevents vacuum backflow in the branch circuit.

[0061] In this embodiment, the vacuum circuit system further includes three branches, each corresponding to one of the three vacuum load units. Each branch is connected to the outlet of the first one-way valve 114. Furthermore, a branch pressure regulating valve 12 is provided at the inlet of each branch to adjust the vacuum pressure at the inlet to the pressure value required by the load unit. In this embodiment, since both the first vacuum load unit 17 and the second vacuum load unit 18 are handling arms, they can use the same branch pressure regulating valve 12. In each branch, a first two-position three-way valve 14, a pressure sensor 15, and a pressure control component 16 are sequentially connected from the inlet to the outlet. Each pressure control component 16 is connected to each vacuum load unit. The pressure control component 16 is positioned adjacent to the vacuum load unit, allowing for real-time adjustment of the pressure difference between the load end of the vacuum load unit and the pressure control component 16, ensuring the vacuum pressure in the gas path and preventing a sudden drop in vacuum pressure from affecting the vacuum pressure of other vacuum load units.

[0062] During normal operation, the plant's vacuum air source generates negative pressure, which is first divided into two branches after passing through the main vacuum air circuit 11. One branch first passes through the branch pressure regulating valve 12 and then splits into the first branch 131 and the second branch 132. The branch pressure regulating valve 12 adjusts the pressure to the normal vacuum pressure required for the first vacuum load unit 17 and the second vacuum load unit 18 to adsorb wafers. In this embodiment, the first vacuum load unit 17 is the first robotic arm, and the second vacuum load unit 18 is the second robotic arm. After the normal operating pressure is introduced into the first branch 131 and the second branch 132, the vacuum pressure in the air circuit can be observed through the pressure sensor 15. When the two-position three-way valve is open, it connects the vacuum pipeline, and the first and second robotic arms activate the vacuum. When closed, the first and second robotic arms are connected to the atmospheric environment of the equipment to achieve the effect of releasing the vacuum. Furthermore, the pressure can be uploaded to the host computer, and the vacuum logic valve can effectively suppress sudden drops in vacuum pressure. The vacuum entering the third branch 133 also passes through the branch pressure regulating valve 12, the first two-position three-way valve, the pressure sensor 15, and the vacuum logic valve to reach the pre-aligner. Because a vacuum logic valve is set in each branch in this embodiment, it can effectively avoid the situation where the vacuum pressure suddenly drops and the equipment alarms and crashes due to the connection between the end of two or more vacuum circuits and the atmosphere.

[0063] Example 2

[0064] Because vacuum circuit systems have numerous vacuum load units, maintaining a stable vacuum pressure is difficult when multiple units operate simultaneously. Alternatively, when any one or more vacuum load units are unloaded, vacuum leakage at the end of the unit can cause a drop in vacuum pressure, leading to unstable vacuum adsorption and potential equipment downtime or errors. Therefore, this embodiment provides a gas circuit control system for semiconductor devices. It connects at least one vacuum load unit to a compressed air circuit system and incorporates a vacuum generator within the gas circuit structure to achieve vacuum load, thereby alleviating the problems of heavy load and unstable vacuum adsorption in vacuum circuit systems.

[0065] The semiconductor device's pneumatic control system includes a compressed air pneumatic system. (Refer to...) Figure 2 The compressed air system includes a main compressed air passage 21, at least one air flotation structure 223, at least one vacuum load unit, and compressed air branch passages. The main compressed air passage 21 is connected to an air source. In this embodiment, the air source is a plant compressed air source. One end of the main compressed air passage 21 is connected to the air source, and the other end is connected to the air flotation structure 223 and the vacuum load unit respectively through the compressed air branch passages.

[0066] Optionally, the compressed air circuit system includes a shut-off valve 211, which is located in the main compressed air circuit 21 and used to control the opening and closing of the main vacuum circuit 11. In this embodiment, the shut-off valve 211 is a manual shut-off valve. Optionally, the compressed air circuit system includes a pneumatic assembly 212, which is located on the main compressed air circuit 21 and downstream of the shut-off valve 211. The pneumatic assembly 212 includes an air filter 2121, an oil mist separator 2122, and a pressure regulating valve 2123 to clean and regulate the pressure of the compressed air used in the plant. Optionally, a second check valve 213 is also located downstream of the pneumatic assembly 212. This check valve is installed before the air tank to prevent backflow of air in the air tank. Optionally, a second buffer air tank 214 is located downstream of the second check valve 213, and the end of the second buffer air tank 214 is connected to the compressed air branch. The added second buffer gas tank 214 can enhance the anti-interference ability of the gas circuit and help stabilize the gas circuit.

[0067] The number of compressed air branches can be determined based on the number of air flotation structures 223 and vacuum load units 234. A compressed air circuit system can be configured with one air flotation structure 223 and one vacuum load unit 234, corresponding to two compressed air branches. Of course, multiple air flotation structures 223 and vacuum load units 234 can be configured as needed, thus correspondingly providing multiple branches; this embodiment does not impose any limitations on this.

[0068] In this embodiment, the compressed air system includes an air flotation structure 223 and a vacuum load unit 234. Two compressed air branches are provided: a first compressed air branch 22 and a second compressed air branch 23. The first compressed air branch 22 is connected to the air flotation structure 223, and the second compressed air branch 23 is connected to the vacuum load unit 234. The first compressed air branch 22 includes, in sequence along the airflow direction, a first pressure regulating valve 221, a normally open solenoid valve 222, and the air flotation structure 223. The first pressure regulating valve 221 adjusts the air pressure to meet the normal operating requirements of the air-float motion table. The normally open solenoid valve 222 is used to close in special circumstances to cut off the compressed air. The second compressed air branch 23 includes, in sequence along the airflow direction, a second pressure regulating valve 231, a normally closed solenoid valve 232, a vacuum generator unit 233, a pressure sensor 15, and the vacuum load unit 234. Similarly, the second pressure regulating valve 231 adjusts the air pressure to meet the requirements of the vacuum load unit. The normally closed solenoid valve 232 is used to control the opening and closing of the gas path. Optionally, the vacuum generating unit 233 includes at least a vacuum generator 2331. The vacuum generator 2331 generates a negative pressure chamber through high-speed flowing compressed air, creating a vacuum in the pipeline. In this embodiment, the vacuum generating unit 233 also includes a filter 2332 and a silencer 2333. The filter 2332 ensures the cleanliness of the vacuum generator 2331, while the silencer 2333 prevents the discharged compressed air from generating noise. Optionally, a one-way valve (not shown in the figure) is also provided between the vacuum generating unit 233 and the pressure sensor 15. This one-way valve prevents backflow into the vacuum generator. The pressure sensor 15 can convert the pressure into an analog electrical signal and transmit it to the host computer for real-time pressure monitoring. The host computer can also set a pressure alarm threshold to avoid potential risks caused by insufficient or excessive vacuum.

[0069] In this embodiment, the air-floating structure 223 is an air-floating worktable used to support or move wafers, photomasks, and other workpieces. Air-floating holes are provided on the surface of the air-floating worktable. The air-floating worktable is connected to the main compressed air passage 21, and compressed air in the main compressed air passage 21 is transmitted to the air-floating holes to support or transport the workpieces located thereon. A vacuum load unit is used to perform wafer adsorption operations. Optionally, the vacuum load unit can be one of a handling arm, a pre-alignment unit, or a wafer chuck. Optionally, there is at least one vacuum load unit in the vacuum passage system, but multiple units can also be configured. In this embodiment, the vacuum load unit is a wafer chuck.

[0070] During normal operation, compressed air from the plant's compressed air source is introduced into two compressed air branches via the main compressed air line 21. In the first compressed air branch 22, the compressed air is adjusted to the normal operating pressure of the air-float platform by the first pressure regulating valve 221 to meet its operational needs. In the second compressed air branch 23, the compressed air is adjusted to a suitable vacuum pressure generated by the vacuum generating unit 233 by the second pressure regulating valve 231 to ensure proper wafer adsorption by the wafer chuck. The compressed air then passes through the normally closed solenoid valve 232 to the vacuum generating unit 233. The compressed air is discharged through a silencer, and the resulting negative pressure vacuum passes through a filter 2332 and a one-way valve to reach the wafer chuck. A pressure sensor 15 is installed before the wafer chuck to monitor the vacuum pressure and transmit the data to the host computer. Because the vacuum generator 2331 is used to generate the vacuum instead of directly using the factory's vacuum air source, it is more independent than other vacuum units. This avoids the sudden drop in vacuum pressure that occurs when any one or more of the multiple vacuum load units are turned on simultaneously and before the wafers are adsorbed, thus preventing equipment alarms and shutdowns that would affect the normal operation of the machine. The vacuum generator also avoids small fluctuations in the factory's vacuum, generating a very stable and repeatable vacuum pressure. This prevents the wafers from adsorbing the wafers due to fluctuations in vacuum pressure, which could lead to different degrees of adhesion between the wafers and the chucks, thus reducing the accuracy and stability of quantity detection or processing. In addition, the vacuum generator only relies on compressed air, which can reduce the factory's investment in vacuum systems, resulting in cost reduction and energy saving.

[0071] In some cases, when the wafer chuck releases the wafer from its gripper, atmospheric pressure alone may not be sufficient to promptly release the residual negative pressure at the wafer-chuck contact point. In such situations, when the robotic arm removes the wafer from the chuck, the force exerted on the wafer is opposite to the residual vacuum suction, potentially causing deformation of the wafer. To address this technical problem, this embodiment establishes pressure balance by introducing compressed air into the chuck, releasing the residual vacuum and achieving a vacuum-breaking effect. Specifically, refer to... Figure 3In this embodiment, a vacuum breaking unit and a controller (not shown in the figure) are provided in the compressed air circuit system. The vacuum breaking unit is located in the second compressed air branch 23, which is connected in parallel with the vacuum generating unit upstream of the vacuum load unit 234. The controller is configured to: after the vacuum load unit completes its process and cuts off the main compressed air circuit 21, control the vacuum breaking unit to open, and introduce air into the vacuum load unit to eliminate residual vacuum. In this embodiment, the vacuum breaking unit includes a vacuum breaking branch 242, which is located upstream of the vacuum load unit 234 and connected in parallel with the vacuum generating unit 233. Optionally, the vacuum breaking unit also includes a second two-position three-way valve 241, which includes a first output terminal and a second output terminal. The first output terminal is connected to the vacuum generating unit 233, and the second output terminal is connected to the inlet terminal of the vacuum breaking branch 242. The outlet terminal of the vacuum breaking branch 242 is connected to the vacuum load unit 234. The controller can control the two-position three-way valve to connect to either the vacuum breaking branch or the vacuum generating unit. Optionally, a flow rate control valve 243 is also provided on the vacuum breaking branch 242. This flow rate control valve 243 is used to control the gas pressure to eliminate residual vacuum. When wafers need to be adsorbed, the second two-position three-way valve 241 is opened, and compressed air passes through the second two-position three-way valve 241 to reach the vacuum generating unit 233 to generate a vacuum for the suction cup to adsorb the wafers. When adsorption needs to be released, the second two-position three-way valve 241 is closed, and compressed air finally reaches the suction cup through the flow rate control valve 243, where the compressed air plays the role of breaking the vacuum. The flow rate control valve adjusts the compressed air supplied to the suction cup from 243 to a suitable flow rate, ensuring that the vacuum is broken without affecting the displacement of the wafers. Furthermore, this embodiment does not require a separate connection or setting of a vacuum breaking air source; the vacuum breaking air source can be obtained directly by connecting the two-position three-way valve to the compressed air circuit, making the structure simpler.

[0072] Existing vacuum chucks for semiconductor equipment mostly use factory vacuum as the negative pressure source. The vacuum chuck of this invention uses a vacuum generator to produce vacuum, achieving relative system independence and avoiding alarms and system crashes caused by fluctuations in equipment vacuum pressure. Simultaneously, the vacuum pressure generated by the vacuum generator ensures repeatability and stability, which is beneficial to the accuracy and stability of measurement results or price processing procedures in various semiconductor equipment.

[0073] Semiconductor equipment often has multiple vacuum load units. Existing semiconductor equipment only uses solenoid valves to control the vacuum opening and closing at the front end of each vacuum load unit. This invention adds a pressure control component, such as a vacuum logic valve, between each vacuum load unit. Therefore, in a multi-vacuum load unit system, when some units are not adsorbing wafers, their corresponding vacuum logic valves automatically close, thus concentrating the limited vacuum flow to the units currently adsorbing wafers. This effectively avoids the problem of insufficient overall pressure caused by parallel leakage and prevents sudden drops in vacuum pressure, equipment alarms, and shutdowns caused by two or more vacuum circuit ends being connected to the atmosphere.

[0074] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A gas path control system of a semiconductor apparatus, characterized by, The air path control system includes a vacuum air path system, which includes: The main vacuum circuit is connected to the vacuum source; At least two vacuum load units are used to perform wafer adsorption operations; At least two branches are provided, each branch corresponding to a vacuum load unit, and each vacuum load unit is connected to the end of the corresponding branch. A pressure control component is disposed upstream of the adsorption surface of each vacuum load unit. When the load end of the vacuum load unit is in an unloaded state, the pressure control component controls the vacuum to be cut off to the vacuum load unit to maintain the upstream vacuum pressure; when the load end is in an adsorption state, the pressure control component controls the vacuum to be opened to the vacuum load unit to establish an adsorption path from the vacuum source to the load end.

2. The air path control system according to claim 1, characterized by, The pressure control component includes a vacuum logic valve. When the load end of the vacuum load unit is in an unloaded state, the high-speed airflow generated by the vacuum source drives the valve core to operate, thereby cutting off the air path and maintaining the upstream vacuum pressure. When the load end is in an adsorption state, the airflow stops, and the valve core automatically opens under the action of the reset element, establishing an adsorption path from the vacuum source to the load end.

3. The air path control system according to claim 1, characterized by, The vacuum circuit system also includes: The main on / off valve is installed in the main vacuum circuit and is used to control the on / off state of the main vacuum circuit.

4. The air path control system according to claim 1, characterized by, The vacuum circuit system also includes: A pressure regulating valve is provided in the main vacuum path and / or each of the branch paths for regulating the vacuum pressure in the air path.

5. The air path control system according to claim 3, characterized in that, The vacuum circuit system also includes: A buffer gas storage tank is installed in the main vacuum circuit and downstream of the main on / off valve. It is used to store vacuum when the main on / off valve is open and to release vacuum to suppress pressure fluctuations when the vacuum load unit is turned on.

6. The air path control system according to claim 5, characterized in that, The vacuum circuit system also includes: A pressure sensor is installed between the buffer gas storage tank and the vacuum load unit to detect the actual vacuum pressure supplied to the vacuum load unit in real time.

7. The air path control system according to claim 1, characterized in that, The vacuum load unit is one of a handling arm, a pre-alignment unit, or a wafer chuck.

8. The air path control system according to claim 1, characterized in that, The air circuit control system further includes a compressed air circuit system, which includes: The main compressed air circuit is connected to the air source. At least one air flotation structure; At least one vacuum load unit is used to perform wafer adsorption operations; The compressed air branch is provided in a one-to-one correspondence with the air flotation structure and the vacuum load unit, and the air flotation structure and the vacuum load unit are respectively located at the end of the corresponding branch; A vacuum generating unit is located on the compressed air branch where the vacuum load unit is located, and is located upstream of the vacuum load unit. It is used to convert the input air into vacuum gas to drive the vacuum load unit to work.

9. The air path control system according to claim 8, characterized in that, The compressed air circuit system includes: A shut-off valve is installed in the main compressed air circuit to control the opening and closing of the main vacuum circuit.

10. The air path control system according to claim 9, characterized in that, The compressed air circuit system also includes: A pneumatic assembly is disposed on the main compressed air line and downstream of the shut-off valve; the pneumatic assembly includes an air filter, an oil mist separator, and a pressure regulating valve.

11. The gas path control system according to claim 8, characterized in that, The compressed air circuit system also includes: A vacuum breaking unit is disposed in the compressed air branch and connected in parallel with the vacuum generating unit upstream of the vacuum load unit; The controller is configured to: after the vacuum load unit completes the process and cuts off the main compressed air path, control the vacuum breaking unit to open and introduce air into the vacuum load unit to eliminate the residual vacuum.

12. The gas path control system according to claim 11, characterized in that, The vacuum breaking unit includes: A two-position three-way valve includes a first output terminal and a second output terminal, wherein the first output terminal is connected to the vacuum generating unit; The vacuum breaking branch has its inlet end connected to the second output end and its outlet end connected to the vacuum load unit.

13. The air path control system according to claim 12, characterized in that, The vacuum breaking unit also includes: A flow rate control valve is installed on the vacuum breaking branch to control the gas pressure for eliminating residual vacuum.

14. A semiconductor device, characterized by comprising: Including the pneumatic control system of the semiconductor device as described in any one of claims 1 to 13.

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