Cold pump baffle position adjusting device, vacuum chamber and vacuum adjusting method

Abstract

The invention belongs to the technical field of semiconductor equipment, and discloses a cold pump baffle position adjusting device, a vacuum chamber and a vacuum adjusting method, and the device comprises a mounting bracket which is mounted on the outer wall of the vacuum chamber; the driving transmission mechanism is mounted on the mounting bracket and is used for applying axial push-pull force to the connecting rod; the connecting rod is arranged in the corrugated pipe, one end of the connecting rod is connected with the output end of the driving transmission mechanism, and the connecting rod is used for generating axial linear motion under the driving of the driving transmission mechanism; one end of the corrugated pipe is connected to the inner wall of the vacuum cavity in a sealed mode, and the other end of the corrugated pipe is connected with the other end of the connecting rod and the baffle in a sealed mode. The position adjustment of the baffle can be controlled by operating outside the vacuum chamber, the baffle adjustment process steps are simplified, and the equipment debugging efficiency is improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of semiconductor equipment, and in particular, relates to a cold pump baffle position adjusting device, a vacuum chamber and a vacuum adjusting method. BACKGROUND

[0002] At present, cold pumps are widely used in physical vapor deposition (PVD) equipment for manufacturing thin films. In the process flow, the process pressure is an important parameter affecting the process result, and the process pressure is realized by adjusting the height of the baffle of the cold pump. The working principle of the cold pump is not to extract gas molecules to achieve vacuum as the mechanical pump does, but to utilize the random thermal motion characteristics of gas molecules in the chamber. The cold pump functions to provide an extremely cold surface in the chamber by using a cold plate. When the gas molecules collide with the cold surface in random motion, they lose kinetic energy and are captured and frozen on the cold plate inside the pump, thereby achieving vacuum. In this way, the number of gas molecules in the chamber becomes smaller and smaller, and the vacuum degree becomes higher and higher.

[0003] The cold pump is sealed and installed at the mounting interface of the vacuum chamber, and the cold plate extends into the vacuum chamber. The baffle is arranged between the gas molecule heat source and the cold plate in the chamber, and is used to block the movement of gas molecules and affect the pumping speed of the cold pump, thereby affecting the process pressure of the vacuum chamber. Therefore, the structure of the baffle is crucial to the efficient operation of the vacuum system.

[0004] At present, the baffle is fixedly installed, and the design height of the cold pump baffle is determined by the type of the chamber. In the process, the gas inlet amount cannot be controlled by freely adjusting the height to realize the function of adjusting the pumping speed of the cold pump. If the height of the cold pump baffle needs to be adjusted, the chamber needs to be filled to the atmospheric state, the cold pump baffle needs to be taken out, the screw gap needs to be adjusted to realize the function of adjusting the pumping speed of the cold pump, and after completion, the chamber needs to be restored to vacuum. This greatly reduces the efficiency of equipment debugging.

[0005] The current cold pump baffle adjusting mode is relatively cumbersome. Therefore, a device is needed that can adjust the pumping speed of the cold pump without damaging the chamber environment and in the process. SUMMARY

[0006] The cold pump baffle position adjusting device, the vacuum chamber and the vacuum adjusting method of the present application drive the baffle to move the position through the lead screw transmission, thereby adjusting the distance between the baffle and the pump port to realize the adjustment of the pumping speed of the cold pump. Moreover, the stretchability of the bellows is good, so that even in the process of moving the baffle, the reliable sealing of the vacuum chamber can be ensured.

[0007] According to one aspect of the present application, a cold pump baffle position adjusting device is provided, comprising: a mounting bracket installed on the outer wall of the vacuum chamber; A driving transmission mechanism is installed on the mounting bracket for applying axial push-pull force to the connecting rod; A connecting rod is placed in the bellows, one end of which is connected to the output end of the driving transmission mechanism for generating axial linear motion under the drive of the driving transmission mechanism; The bellows is sealed and connected to the inner wall of the vacuum chamber at one end, and is sealed and connected to the other end of the connecting rod and the baffle at the other end.

[0008] Optionally, the driving transmission mechanism includes a driving mechanism and a lead screw and a nut, one end of the mounting bracket is fixedly connected to the outer wall of the vacuum chamber, the output end of the driving mechanism is used to drive the rotation of the lead screw, the nut is threadedly connected with the lead screw, and the connecting rod is fixedly connected with the nut.

[0009] Optionally, the driving mechanism is a rotary motor, the rotary motor is installed at the other end of the mounting bracket, and the output shaft of the rotary motor is fixedly connected with the lead screw.

[0010] Optionally, the mounting bracket includes a first mounting plate and a second mounting plate arranged in parallel and spaced apart, and a support rod connected therebetween, the first mounting plate has a first exposed hole for the connecting rod to pass through, the second mounting plate is used for mounting the rotary motor, and the second mounting plate has a second exposed hole for the output shaft of the rotary motor to pass through.

[0011] Optionally, the support rod is used to limit the rotation of the nut.

[0012] Optionally, a transparent shielding cover is further arranged between the first mounting plate and the second mounting plate.

[0013] Optionally, one end of the bellows is fixedly connected with a third mounting plate, the third mounting plate is used to seal and connect the one end of the bellows to the inner side of the vacuum chamber, the other end of the bellows is aligned with the first exposed hole, and the connecting rod is sealed and connected to the other end of the bellows through the first exposed hole and the port.

[0014] Optionally, the other end of the bellows is further fixedly connected with a fourth mounting plate, and the baffle has a fifth mounting plate arranged at the upper end, the baffle is installed at the other end of the bellows by clamping the baffle through the fourth mounting plate and the fifth mounting plate.

[0015] Optionally, a control module is further included, the control module is connected with the driving transmission mechanism and a pressure sensor for measuring the vacuum degree in the vacuum chamber, the control module is used to compare the actual pressure in the vacuum chamber with a target pressure, calculate the pressure deviation, and further send a control instruction to the driving transmission mechanism to adjust the position of the baffle according to the pressure deviation.

[0016] Optionally, the baffle plate has a through hole at a position corresponding to the support column of the cold pump.

[0017] According to an aspect of the present application, there is also provided a vacuum chamber comprising a pedestal for carrying a wafer, a cold pump, and the cold pump baffle plate position adjusting device of any one of the preceding claims.

[0018] According to an aspect of the present application, there is also provided a vacuum adjusting method using the cold pump baffle plate position adjusting device, comprising the following steps: Step S1, the control module obtains the actual pressure in the vacuum chamber, and compares the actual pressure with the target pressure to obtain a pressure deviation; Step S2, the pressure deviation is compared with a pressure deviation threshold value, if the pressure deviation is less than the pressure deviation threshold value, the control module does not send a baffle plate position adjusting instruction, if the pressure deviation is greater than or equal to the pressure deviation threshold value, the control module sends a baffle plate position adjusting instruction to the drive transmission mechanism, so that the baffle plate moves to adjust the distance from the pump port until the pressure deviation is less than the pressure deviation threshold value.

[0019] Optionally, if the pressure deviation is greater than or equal to the pressure deviation threshold value, and the pressure in the vacuum chamber is too low, the drive transmission mechanism controls the screw to rotate forward, and the baffle plate moves to reduce the distance from the pump port; If the pressure in the vacuum chamber is too high, the drive transmission mechanism controls the screw to rotate in reverse, and the baffle plate moves to increase the distance from the pump port.

[0020] The cold pump baffle plate position adjusting device, the vacuum chamber and the vacuum adjusting method of the present application have the following beneficial effects compared with the prior art: (1) The screw transmission drives the baffle plate to move to adjust the pumping speed of the cold pump. The adjusting drive transmission mechanism is outside the vacuum chamber, so it is not necessary to fill the chamber to atmospheric pressure for adjustment, and it is not necessary to restore the chamber to a vacuum state, thus simplifying the baffle plate adjustment process steps and improving the equipment debugging efficiency.

[0021] (2) The corrugated pipe has good stretchability. One end of the corrugated pipe is sealingly connected to the vacuum chamber, the other end of the corrugated pipe is sealingly connected to the baffle plate through the fourth mounting plate and the fifth mounting plate, and the connecting rod is arranged inside the corrugated pipe. During the movement of the baffle plate driven by the connecting rod, one end of the corrugated pipe moves with it. Since the corrugated pipe has good stretchability, it can maintain the sealing of the vacuum chamber.

[0022] (3) The screw transmission drives the baffle plate to move to adjust the pumping speed of the cold pump. The baffle plate moves efficiently and reliably. In the past, the height of each support column was adjusted to adjust the position of the baffle plate, which was troublesome. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a perspective view of a cold pump baffle position adjusting device according to an embodiment of the present application; Figure 2 is a schematic view of a cold pump baffle position adjusting device connected to a baffle according to an embodiment of the present application; Figure 3 is a schematic view of a cold pump baffle position adjusting device mounted on a vacuum chamber according to an embodiment of the present application.

[0024] Figure 4 is a schematic view of a vacuum chamber according to an embodiment of the present application.

[0025] Reference signs: mounting bracket 1, drive transmission mechanism 2, lead screw 3, nut 4, connecting rod 5, bellows 6, baffle 7, first mounting plate 101, second mounting plate 102, support rod 103, first mounting hole 1011, first exposed hole 1012, second mounting hole 1021, second exposed hole 1022, shielding cover 104, third mounting plate 601, fourth mounting plate 602, fifth mounting plate 701, support column 702, vacuum chamber 200, base 400, cold pump 300, cold pump baffle position adjusting device 100, valve 310. DETAILED DESCRIPTION

[0026] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0027] A cold pump is mounted on a mounting interface of a vacuum chamber, a cold plate extends into the interior of the vacuum chamber, and a baffle is arranged between a gas molecule heat source and the cold plate in the chamber. Currently, the baffle is fixedly mounted, and a support column 702 is arranged between the baffle and the mounting interface. In order to adapt to different process pressure requirements, the height of the support column 702 can be adjusted to adapt to the position of the baffle required by different process pressures. However, the adjustment is made in the vacuum chamber, and when the position of the cold pump baffle needs to be adjusted, the chamber needs to be filled to the atmospheric state first, and then the personnel can operate, open the chamber, take out the cold pump baffle, adjust the height of the support column, realize the function of adjusting the pumping speed of the cold pump, and then restore the vacuum of the chamber. This greatly reduces the efficiency of equipment debugging.

[0028] The present application can adjust the position of the baffle through the lead screw drive, can quickly adjust the position of the baffle in the process, and is flexible and applicable to different process pressure requirements. Moreover, the present application combines the good telescopic characteristics of the bellows with the lead screw drive structure for controlling the position of the baffle, so that the bellows can maintain good sealing effect of the vacuum chamber in the process of driving the baffle position by the lead screw.

[0029] It should be noted that the mounting interface of the cold pump is usually at the lower end of the vacuum chamber, which makes the pump port of the cold pump horizontally arranged and the baffle horizontally blocked above the pump port. Because the particulate matter on the inner wall of the vacuum chamber or the tiny contaminants generated in the process will fall due to gravity. These contaminants will directly fall on the baffle of the cold pump instead of falling on the cold plate, which greatly reduces the maintenance frequency and performance degradation risk of the cold pump. However, the present application does not exclude that the cold pump can be installed on the side of the vacuum chamber. Hereinafter, the cold pump installed at the lower end of the vacuum chamber is taken as an example for illustration.

[0030] Figure 1 is a perspective view of the cold pump baffle position adjusting device of the present application embodiment, Figure 2 is a schematic view of the cold pump baffle position adjusting device of the present application embodiment connected with the baffle. Please refer to Figure 1 Figure 2 According to one aspect of the present application, the present embodiment provides a cold pump baffle position adjusting device, comprising a mounting bracket 1 fixedly connected with a vacuum chamber for mounting other adjusting members; a drive transmission mechanism 2 for applying axial push-pull force to a connecting rod 5; the connecting rod 5 is connected with the output end of the drive transmission mechanism 2 at one end; a bellows 6 having a baffle 7 mounted thereon, the bellows 6 is sealingly connected with the other end of the connecting rod 5 for linear movement together with the connecting rod 5, so as to adjust the position of the baffle.

[0031] The mounting bracket 1 is used for mounting the cold pump baffle position adjusting device outside the vacuum chamber, comprising a first mounting plate 101 and a second mounting plate 102 arranged in parallel and spaced apart, and a support rod 103 connected between the first mounting plate 101 and the second mounting plate 102. The first mounting plate 101 has a plurality of first mounting holes 1011, which can be uniformly arranged in the circumferential direction of the first mounting plate. For example, the first mounting plate is a square plate, and a first mounting hole 1011 is arranged at each right angle. For example, the first mounting plate is a circular plate, and a plurality of first mounting holes are uniformly arranged in the circumferential direction. The first mounting hole 1011 is used for fixedly mounting the mounting bracket 1 on the outer wall of the vacuum chamber. The mounting bracket 1 can be fixedly mounted on the outer wall of the vacuum chamber by passing a bolt through the first mounting hole 1011. The present embodiment also does not exclude that other connection methods can be used to fixedly mount the mounting bracket 1 on the outer wall of the vacuum chamber, such as welding, clamping, etc.

[0032] ​The first mounting plate 101 has a first exposed hole 1012 at its center for the connecting rod 5 to pass through.

[0033] The second mounting plate 102 is used to mount a drive transmission mechanism 2, which may include a rotary motor, a lead screw, and a nut. The second mounting plate 102 has a second mounting hole 1021, through which bolts can be passed to the second mounting hole 1021 and the housing of the rotary motor to fix the housing of the rotary motor onto the mounting bracket 1. The second mounting plate 102 also has a second exposed hole 1022 for the output shaft of the rotary motor to pass through. The output shaft of the rotary motor is coaxially connected to the lead screw 3, which can drive the lead screw to generate rotational motion.

[0034] Alternatively, a lead screw motor can be used directly as the drive transmission mechanism. Since the lead screw and the output shaft of the rotary motor are integrally formed, a coupling is not required to connect the lead screw and the rotary motor. This is more direct than traditional drive methods, eliminates the need for couplings and other transmission components, resulting in a simpler overall structure, saving space and improving economic efficiency.

[0035] Furthermore, the first mounting hole 1011 can be aligned with the second mounting hole 1021, allowing a long bolt to pass through both the second mounting hole 1021 and the first mounting hole 1011 simultaneously, thereby mounting the rotary motor and the mounting bracket onto the outer wall of the vacuum chamber. Alternatively, the mounting bracket can be mounted onto the outer wall of the vacuum chamber using a bolt passing through the first mounting hole, and then the rotary motor can be mounted onto the mounting bracket using a bolt passing through the second mounting hole.

[0036] The above-described drive transmission mechanism using a rotary motor and a lead screw nut is merely exemplary; in fact, this application does not limit the form of the drive transmission mechanism. For example, the drive transmission mechanism can also be a gear transmission, where a rotary motor drives a first gear to rotate, and an integral second gear is machined at the end of the lead screw. The meshing of the first and second gears drives the lead screw to generate rotational motion. In this manner, the rotary motor and the first gear can be mounted on the outer wall of the vacuum chamber, and the lead screw can be mounted on the second mounting plate 102 via bearings. The rotational power can then be transmitted to the lead screw through the rotation of the rotary motor.

[0037] Similarly, the drive transmission mechanism can also be a belt drive, chain drive, or other drive transmission forms, as long as it can drive the lead screw to produce rotational motion. The specific structure will not be described in detail here.

[0038] Alternatively, this application may also employ hydraulic rods, pneumatic rods, linear push rods, etc., connected to the connecting rod to generate linear push-pull force. However, this application preferably uses a drive transmission method employing a rotary motor and a lead screw and nut. The following description uses only the lead screw and nut drive transmission method as an example.

[0039] A support rod 103 is also connected between the first mounting plate 101 and the second mounting plate 102. The two ends of the support rod 103 can be fixedly connected to the first mounting plate 101 and the second mounting plate 102 respectively. The installation position of the support rod 103 should prevent the nut 4 from rotating, that is, the support rod 103 restricts the rotational movement of the nut 4.

[0040] The nut 4 is screwed onto the lead screw 3. In the prior art, the lead screw 3, as the driving element, performs helical transmission with the nut 4 in two forms: the lead screw 3 rotates and the nut 4 moves; the nut 4 is fixed, and the lead screw 3 rotates and moves. This application adopts a transmission form in which the lead screw 3 rotates and the nut 4 moves, which requires restricting the rotation of the nut 4. There are many structures for restricting the rotation of the nut. For example, the nut 4 can be a block with two parallel sidewalls, such as... Figure 1 As shown, two parallel sidewalls are machined on the side of the round nut, for example, by milling or other mechanical processing methods. At least two support rods 103 are located on the outer sides of the two sidewalls, and the distance between the two support rods 103 is equal to the distance between the two sidewalls, which prevents the nut from rotating. Thus, the nut 4 can move along the length of the lead screw by rotating the lead screw.

[0041] Of course, to ensure the stability of the mounting bracket, multiple support rods can be installed between the first and second mounting plates.

[0042] One end of the connecting rod 5 is coaxially fixedly connected to the nut 4, and is used to move linearly along with the nut.

[0043] In some embodiments, a shield 104 is further provided between the first mounting plate and the second mounting plate. The shield 104 may be a U-shaped transparent shell, used to fasten between the first mounting plate and the second mounting plate from the side, thereby protecting the safety of external operators. The connection between the shield and the mounting bracket may be a snap-fit ​​connection or a fastener connection.

[0044] One end of the bellows 6 is fixedly connected to a third mounting plate 601, and the other end is fixedly connected to a fourth mounting plate 602. The third mounting plate 601 is used to fix one end of the bellows to the inside of the vacuum chamber. The opening of the other end of the bellows 6 is aligned or substantially aligned with the first exposed hole 1012. This allows the connecting rod 5 to pass through the first exposed hole 1012 and be fixedly connected to the other end of the bellows.

[0045] The fourth mounting plate 602 is fixedly connected to the baffle 7. The fourth mounting plate may have multiple mounting holes. The baffle 7 is provided with a fifth mounting plate 701 at its upper end. The baffle 7 is clamped by the fourth mounting plate 602 and the fifth mounting plate 701. Multiple bolts are passed through the fourth mounting plate 602, the baffle 7 and the fifth mounting plate 701 to install the baffle 7 at the other end of the corrugated pipe 6.

[0046] In some embodiments, since the pump inlet of the cold pump is provided with a support column 702 to support the height of the baffle, the baffle may have a through hole at the position corresponding to the support column 702, thereby allowing the height of the baffle to be adjusted over the support column on the cold pump. It should be noted that this is a baffle configuration applicable to current cold pump structures. Alternatively, a completely new cold pump could be used, eliminating the need for a support column and relying entirely on screw drive to adjust the baffle position.

[0047] One end of the bellows is fixedly connected to the inside of the vacuum chamber by the third mounting plate 601, and the opening on this side forms a sealed connection with the first exposed hole 1012, thereby ensuring that there is no leakage inside the vacuum chamber.

[0048] A corrugated pipe is a flexible pipe fitting with a corrugated shape. Compared with ordinary hoses of the same diameter and material, the corrugated structure significantly improves pressure resistance. While meeting strength requirements, its weight is far lower than that of rigid pipes and fittings that achieve the same function. More importantly, corrugated pipes have good extensibility and compensation capabilities. They can be stretched or compressed along their axis, absorbing changes in piping system dimensions caused by thermal expansion and contraction, equipment vibration, or installation errors. In this embodiment, the corrugated pipe is applied so that as the connecting rod moves with the nut, the connecting rod drives the corrugated pipe to expand and contract, while the baffle fixedly connected to the corrugated pipe also moves accordingly. Due to the good extensibility of the corrugated pipe, it is itself a expandable sealing body. After being fixedly connected to the inner wall of the vacuum chamber, a reliable seal can be achieved, ensuring good sealing of the vacuum chamber while adjusting the position of the baffle.

[0049] The following describes the operation of the cold pump baffle position adjustment device. During the process, the gas flow rate is set and remains constant. The pumping speed is mainly determined by the cold pump, while the pressure is the target variable that needs to be controlled. With a fixed inlet gas flow rate Q, the chamber pressure P is inversely proportional to the cold pump's pumping speed. If it is necessary to reduce the vacuum chamber pressure, the pumping speed is increased; if it is necessary to increase the vacuum chamber pressure, the pumping speed is decreased.

[0050] The nut causes the baffle to move downwards, getting closer to the pump inlet of the cold pump. This increases the flow resistance of gas from the vacuum chamber to the pump, preventing the pump's powerful suction capacity from being fully utilized in the vacuum chamber, thus reducing the pumping speed.

[0051] More specifically, when the actual pressure is less than the target pressure, the nut moves the baffle downwards, reducing the pumping speed and allowing more gas to remain in place, thus increasing the pressure to the target value.

[0052] The nut moves the baffle upward, away from the pump inlet of the cold pump, which reduces the flow resistance of gas from the vacuum chamber to the pump. This means that the pump's powerful suction capacity cannot be fully applied to the vacuum chamber, thus increasing the pumping speed.

[0053] More specifically, when the actual pressure is greater than the target pressure, the gas is pumped away faster by increasing the pumping speed, thereby reducing the pressure to the target value.

[0054] By controlling the movement of the baffle through the nut and screw drive, the position of the baffle can be finely adjusted. The process of changing the pumping speed is smooth and continuous, avoiding sudden changes in airflow or pressure, which is crucial for the highly demanding PVD process.

[0055] In some embodiments, a control module may also be included, such as a PLC. This control module is connected to the drive transmission mechanism and can control parameters such as the start and stop of the drive transmission mechanism and its rotational speed. Furthermore, the control module is also connected to a pressure sensor that measures the vacuum level within the vacuum chamber, enabling real-time acquisition of pressure data within the vacuum chamber. Additionally, the control module may have an input unit for inputting the target pressure of the vacuum chamber, or it may be connected to the process control system of the vacuum chamber to obtain the target pressure from it.

[0056] The control module can compare the actual pressure in the vacuum chamber with the target pressure in real time, calculate the pressure deviation, and then send control commands to the drive transmission mechanism to adjust the position of the baffle according to the pressure deviation.

[0057] Specifically, if the pressure inside the vacuum chamber is too low, the control module sends a command to the drive transmission mechanism, which controls the lead screw to rotate forward, moving the baffle downwards a certain distance, reducing the distance between the baffle and the pump inlet, thus reducing the actual pumping speed of the cold pump in the chamber. If the pressure inside the vacuum chamber is too high, the control module sends a command to the drive transmission mechanism, which controls the lead screw to rotate in the opposite direction, moving the baffle upwards a certain distance, increasing the distance between the baffle and the pump inlet, thus increasing the actual pumping speed of the cold pump in the chamber.

[0058] According to one aspect of this application, a vacuum chamber 200 is also provided, such as... Figure 4 As shown, the system includes a base 400 for supporting the wafer, a cold pump 300, and the aforementioned cold pump baffle position adjustment device 100. The cold pump 300 is installed outside the vacuum chamber 100, and the valve 310 of the cold pump 300 is installed on the outer wall of the vacuum chamber.

[0059] According to one aspect of this application, a vacuum conditioning method is also provided, comprising the following steps: In step S1, the control module obtains the actual pressure inside the vacuum chamber through the pressure sensor and compares the actual pressure with the target pressure to obtain the pressure deviation.

[0060] The target pressure varies depending on the process. For example, some chemical vapor deposition and low-pressure chemical vapor deposition require a vacuum pressure range of approximately 100 Pa to 1000 Pa. This pressure range is conducive to the chemical reaction between gas molecules, ensuring that there is enough precursor gas to participate in the reaction, so as to obtain an appropriate deposition rate and good step coverage.

[0061] Physical vapor deposition (PVD) and dry etching require vacuum pressures ranging from approximately 0.1 Pa to 10 Pa. For PVD processes, such as sputtering, lower pressures are needed to increase the mean free path of sputtered atoms, allowing them to travel in a straight line from the target to the wafer surface, resulting in well-oriented and strongly bonded films. If the pressure is too high, sputtered atoms will scatter due to frequent collisions, leading to poor film quality. Similarly, dry etching requires lower pressures to generate directional ion bombardment, thus achieving anisotropic etching.

[0062] Ion implantation requires a vacuum pressure range of approximately 10. -4 Pa to 10 -2 In Pa, ion implanters need to accelerate ions to very high energies and precisely control their paths. This must be done under high vacuum to prevent ions from colliding with gas molecules and being scattered, neutralized, or having their energy altered, thus ensuring the accuracy of the implanted dose and the contour of the implantation distribution.

[0063] Based on the different target pressures set for different processes, the control module compares the actual pressure with the target pressure and calculates the pressure deviation.

[0064] In step S2, the control module compares the pressure deviation with a pressure deviation threshold. If the pressure deviation is less than the pressure deviation threshold, the control module does not send a command. If the pressure deviation is greater than or equal to the pressure deviation threshold, the control module sends a command to the drive transmission mechanism to control its operation. The drive transmission mechanism drives the lead screw to rotate, thereby causing the baffle to rise and fall to adjust the distance to the pump inlet until the pressure deviation is less than the pressure deviation threshold.

[0065] Specifically, if the pressure inside the vacuum chamber is too low, the control module sends a command to the drive transmission mechanism, which controls the lead screw to rotate forward, moving the baffle downwards a certain distance, reducing the distance between the baffle and the pump inlet, thus reducing the actual pumping speed of the cold pump in the chamber. If the pressure inside the vacuum chamber is too high, the control module sends a command to the drive transmission mechanism, which controls the lead screw to rotate in the opposite direction, moving the baffle upwards a certain distance, increasing the distance between the baffle and the pump inlet, thus increasing the actual pumping speed of the cold pump in the chamber.

[0066] Specifically, the pressure deviation threshold can be set according to process requirements. For example, the pressure deviation threshold can be ±5% of the target pressure. For example, if the target pressure is 0.1 Pa, then the pressure deviation threshold can be set between 0.095 Pa and 0.105 Pa.

[0067] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications are all within the protection scope of the claims of the present invention.

Claims

1. A cold-pump damper position adjustment device, characterized by, The cold-pump baffle position adjusting device comprises: a mounting bracket mounted on the outer wall of the vacuum chamber; a drive transmission mechanism mounted on the mounting bracket for applying axial push-pull force to the connecting rod; a connecting rod placed in the bellows, one end of which is connected with the output end of the drive transmission mechanism for generating axial linear motion under the drive of the drive transmission mechanism; a bellows, one end of which is sealingly connected to the inner wall of the vacuum chamber, and the other end of which is sealingly connected with the other end of the connecting rod and the baffle.

2. The cold-pump damper position adjustment device of claim 1, wherein, The drive transmission mechanism comprises a drive mechanism and a screw rod and a nut, one end of the mounting bracket is fixedly connected to the outer wall of the vacuum chamber, the output end of the drive mechanism is used to drive the screw rod to rotate, the nut is threadedly connected with the screw rod, and the connecting rod is fixedly connected with the nut.

3. The cold-pump damper position adjustment device of claim 2, wherein, The drive mechanism is a rotary motor, the rotary motor is mounted on the other end of the mounting bracket, and the output shaft of the rotary motor is fixedly connected with the screw rod.

4. The cold-pump damper position adjustment device of claim 3, wherein, The mounting bracket comprises first and second mounting plates arranged in parallel and spaced apart, and a support rod connected therebetween, the first mounting plate is provided with a first exposed hole for the connecting rod to pass through, the second mounting plate is used for mounting the rotary motor, and the second mounting plate is provided with a second exposed hole for the output shaft of the rotary motor to pass through.

5. The cold-pump damper position adjustment device of claim 4, wherein, The support rod is used for limiting the rotation of the nut.

6. The cold-pump damper position adjustment device of claim 4, wherein, A transparent shielding cover is further arranged between the first and second mounting plates.

7. The cold-pump damper position adjustment device of claim 4, wherein, One end of the bellows is fixedly connected with a third mounting plate, the third mounting plate is used for sealingly connecting one end of the bellows to the inner side of the vacuum chamber, the other end of the bellows is aligned with the first exposed hole, and the connecting rod passes through the first exposed hole and the port of the other end of the bellows to be sealingly connected with the other end of the bellows.

8. The cold-pump damper position adjustment device of claim 7, wherein, The other end of the bellows is further fixedly connected with a fourth mounting plate, the upper end of the baffle is provided with a fifth mounting plate, and the baffle is clamped and mounted on the other end of the bellows through the fourth and fifth mounting plates.

9. The cold-pump damper position adjustment device of claim 7, wherein, The cold-pump baffle position adjusting device further comprises a control module connected with the drive transmission mechanism and a pressure sensor for measuring the vacuum degree in the vacuum chamber, the control module is used for comparing the actual pressure in the vacuum chamber with the target pressure, calculating the pressure deviation, and further sending a control instruction to the drive transmission mechanism to adjust the position of the baffle according to the pressure deviation.

10. The cold-pump damper position adjusting device of claim 1, wherein, The baffle is provided with a through hole corresponding to the position of the cold-pump support column.

11. A vacuum chamber, characterized by, The cold-pump baffle position adjusting device comprises: a pedestal for carrying a wafer, a cold pump, and the cold-pump baffle position adjusting device according to any one of claims 1 to 10.

12. A vacuum adjustment method, characterized by, The cold-pump baffle position adjusting device according to claim 9 is used to perform the following steps: Step S1, the control module acquires the actual pressure in the vacuum chamber, compares the actual pressure with the target pressure, and obtains the pressure deviation; Step S2, the pressure deviation is compared with a pressure deviation threshold value, if the pressure deviation is less than the pressure deviation threshold value, the control module does not send a baffle position adjusting instruction, and if the pressure deviation is greater than or equal to the pressure deviation threshold value, the control module sends a baffle position adjusting instruction to the drive transmission mechanism, so that the baffle moves to adjust the distance from the pump port until the pressure deviation is less than the pressure deviation threshold value.

13. The vacuum conditioning method according to claim 12, wherein, If the pressure deviation is greater than or equal to the pressure deviation threshold value, and the pressure in the vacuum chamber is low, the drive transmission mechanism controls the screw to rotate forward, and the baffle moves to reduce the distance from the pump port; If the pressure in the vacuum chamber is high, the drive transmission mechanism controls the screw to rotate reversely, and the baffle moves to increase the distance from the pump port.

Images