Ejector pin structure with uniform stress and electrostatic chuck

Abstract

The utility model discloses a uniformly stressed ejector pin structure and an electrostatic chuck. The ejector pin structure comprises a bearing mechanism and an ejector pin driving mechanism arranged below the bearing mechanism, a plurality of ejector pin through holes in one-to-one correspondence with the ejector pins are formed in the bearing mechanism; the ejector pin driving mechanism comprises an ejector pin moving plate, at least one calibration substrate and a driving bottom plate which are sequentially connected from top to bottom through elastic supporting columns, a plurality of ejector pins are arranged on the ejector pin moving plate, one ends of the ejector pins are fixed to the upper surface of the ejector pin moving plate, the other ends of the ejector pins penetrate through the corresponding ejector pin through holes, and at least one driver is arranged on the driving bottom plate. A driving shaft of the driver penetrates through all the calibration substrates and is fixedly connected with the ejector pin moving plate; when the driver drives the driving shaft to move, the driving shaft drives all the ejector pins to move upwards or downwards in the corresponding ejector pin through holes through the ejector pin moving plate. The horizontal stability between the ejector pin moving plate and the driving bottom plate is improved, and the ejector pin moving plate is prevented from inclining as much as possible during movement.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor technology, and in particular to a uniformly stressed ejector pin structure and an electrostatic chuck. Background Technology

[0002] With the development of technology, the requirements for automation in the semiconductor industry are becoming increasingly stringent. Many devices in the semiconductor industry utilize ejector pin structures. For example, in the reaction chamber of a TEL (Transfer Electrode System), the wafer height is controlled by the raising and lowering of ejector pins. Furthermore, when a wafer is transferred into the reaction chamber of the TEL, the ejector pin mechanism controls the pin to rise, and a vacuum robot places the wafer onto the pin. Then, the ejector pin mechanism controls the pin to descend so that the wafer falls onto the surface of an electrostatic chuck (ESC) to perform the reaction operation. After the reaction is complete, the ejector pin mechanism again controls the pin to rise and lift the wafer, and the vacuum robot then transfers the wafer out of the TEL's reaction chamber. In short, the ejector pin mechanism is crucial for the robot's wafer transfer function.

[0003] In existing ejector plate mechanisms, uneven force distribution during operation can cause the ejector plate to tilt, leading to friction between the ejector plate and the via. This makes the wafers more susceptible to defects, resulting in yield issues. Furthermore, existing ejector plate mechanisms lack monitoring mechanisms to track the tilt of the ejector plate, forcing operators to rely on specific defect descriptions to determine the cause of wafer defects, making the defect assessment process complex and difficult. Utility Model Content

[0004] The purpose of this application is to provide a uniformly stressed ejector pin structure and an electrostatic chuck to solve the problem that uneven stress on the ejector pin plate in existing ejector pin mechanisms causes tilting, which in turn leads to friction between the ejector pin and the through-hole, affecting the relevant wafers and reducing yield.

[0005] In a first aspect, this application provides a uniformly stressed ejector pin structure, including a support mechanism and an ejector pin driving mechanism disposed below the support mechanism; the support mechanism is provided with a plurality of ejector pin through holes corresponding one-to-one with the ejector pins;

[0006] The ejector pin driving mechanism includes an ejector pin moving plate, at least one calibration base plate, and a driving base plate connected sequentially from top to bottom via elastic support columns. The ejector pin moving plate is provided with a plurality of ejector pins, one end of which is fixed to the upper surface of the ejector pin moving plate, and the other end of which passes through the corresponding ejector pin through hole. The driving base plate is provided with at least one driver, and the driving shaft of the driver passes through all the calibration base plates and is fixedly connected to the ejector pin moving plate.

[0007] When the driver drives the drive shaft to move, the drive shaft drives all the ejector pins to move upward or downward in their corresponding ejector pin through holes via the ejector pin moving plate.

[0008] In one embodiment of this application, the supporting mechanism includes a supporting platform and a filter cavity disposed under the supporting platform. The ejector pin through hole penetrates the supporting platform and the filter cavity, and a clamping member fitted onto the ejector pin is disposed inside the filter cavity.

[0009] In one embodiment of this application, the driver is a motor, and the drive shaft is a motor shaft.

[0010] In one embodiment of this application, there are multiple drivers, and the drive shafts of the multiple drivers are uniformly fixed on the ejector pin moving plate.

[0011] In one embodiment of this application, there is one driver, and the drive shaft of the driver is fixed at the center position of the ejector pin moving plate.

[0012] In one embodiment of this application, a clamping member is fitted on the motor shaft between the calibration substrate and the drive base plate.

[0013] In one embodiment of this application, the clamping member includes a sleeve and a sealing ring disposed on the upper end of the sleeve, and the clamping member is fixed to the upper surface of the filter cavity or to the lower surface of the calibration substrate.

[0014] In one embodiment of this application, the ejector driving mechanism further includes a level monitor, which includes a signal reflector vertically disposed on the ejector moving plate and a signal transceiver disposed on one side of the ejector moving plate. When the ejector moving plate is horizontal, the signal transceiver can receive the reflected signal reflected by the signal reflector. When the ejector moving plate is tilted, the signal transceiver cannot receive the reflected signal reflected by the signal reflector.

[0015] In one embodiment of this application, the pin drive mechanism further includes an alarm connected to the level monitor.

[0016] Secondly, this application provides an electrostatic chuck, including the aforementioned uniformly stressed ejector pin structure.

[0017] Compared with the prior art, one or more embodiments of the above solutions may have the following advantages or beneficial effects:

[0018] By applying the uniformly stressed ejector pin structure provided in this embodiment, one or more calibration substrates are set between the ejector pin moving plate and the drive base plate to improve the horizontal stability between them and minimize tilting of the ejector pin moving plate during movement. Clamping components are fitted onto the ejector pins and motor shafts to ensure they are vertical relative to the corresponding through holes, reducing friction between them. The uniform distribution of driving forces on the ejector pin moving plate, either by evenly distributing the drive shafts of multiple drivers under the ejector pin moving plate or by placing the drive shafts at the center of the ejector pin moving plate, further reduces the possibility of tilting. Finally, a level monitoring device is installed on the ejector pin moving plate to monitor its horizontal state in real time. This allows operators to promptly determine the cause of wafer defects based on the monitoring data, reducing the complexity and difficulty of the wafer defect determination process.

[0019] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of this invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used in conjunction with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0021] Figure 1 This is an example diagram showing the tilting of the ejector pin in an existing ejector pin structure.

[0022] Figure 2 This image shows a comparative example of defects on a wafer after it has been transported into and out of the reaction chamber using an existing ejector pin structure.

[0023] Figure 3 The diagram shown is a structural schematic of the uniformly stressed ejector pin structure described in the embodiments of this application.

[0024] Figure 4 The diagram shown is a simplified structural schematic of the electrostatic chuck described in an embodiment of this application.

[0025] Among them, 1 is the support platform, 2 is the ejector pin moving plate, 3 is the calibration base plate, 4 is the drive base plate, 5 is the clamping component, 6 is the sealing ring, 7 is the elastic support, 8 is the ejector pin, 9 is the driver, 10 is the drive shaft, 11 is the filter chamber, 12 is the signal transceiver, and 13 is the signal reflector. Detailed Implementation

[0026] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application 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.

[0027] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. Therefore, the drawings only show the components related to this application and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0028] like Figure 1 and Figure 2 As shown, existing ejector plate mechanisms generally suffer from tilting due to uneven force on the ejector plate, which causes friction between the ejector plate 8 and the through hole, leading to defects in the wafers and affecting the wafer yield. Figure 2 The image in the middle left shows the defect situation of the wafer before it enters the reaction chamber. Figure 2 The right-middle image shows the defects in the wafer after it exits the reaction chamber. Figure 2 It is known that wafer defects caused by uneven stress on the ejector plate have a significant impact on wafer yield. Therefore, the problem of uneven stress on the ejector plate urgently needs to be addressed. Furthermore, because the issue of uneven stress on the ejector plate has not yet received sufficient attention, there is a lack of regulatory mechanisms for this type of problem, resulting in the failure to promptly identify the causes of these defects.

[0029] The following embodiments of this application provide a uniformly stressed ejector pin structure and an electrostatic chuck, which solves the problem that uneven stress on the ejector pin plate of the existing ejector pin mechanism causes friction between the ejector pin and the through hole, affecting the relevant wafer and thus reducing the yield.

[0030] The following will describe in detail the principle and implementation of the uniformly stressed ejector pin structure and electrostatic chuck of this embodiment with reference to the accompanying drawings, so that those skilled in the art can understand the uniformly stressed ejector pin structure and electrostatic chuck of this embodiment without creative effort.

[0031] like Figure 3 As shown, this embodiment provides a uniformly stressed ejector pin structure, specifically including a support mechanism and an ejector pin driving mechanism disposed below the support mechanism.

[0032] The support mechanism is typically located within the reaction chamber to support the wafer. It usually features ejector pin through-holes for ejector pins 8 to pass through, enabling the wafer to be lifted and lowered. The number of ejector pin through-holes on the support mechanism is usually the same as the number of ejector pins 8, and the positions of the through-holes and ejector pins 8 correspond one-to-one. The diameter of the through-holes is slightly larger than the diameter of the ejector pins to allow the ejector pins 8 to move vertically within the through-holes.

[0033] The ejector pin drive mechanism is configured to provide ejector pins 8 and enable their vertical movement. Specifically, the ejector pin drive mechanism includes an ejector pin moving plate 2, a calibration base plate 3, and a drive base plate 4 arranged in parallel sequence. Multiple calibration base plates 3 can be arranged sequentially, and any two adjacent plates are connected by multiple identical elastic supports. These elastic supports can be springs with suitable elasticity and under compression, rubber pillars with a certain degree of elasticity, or other suitable elastic support elements; no fixed restrictions are imposed here. By placing one or more calibration base plates 3 between the ejector pin moving plate 2 and the drive base plate 4, and using elastic supports to connect adjacent plates, the horizontal stability between the ejector pin moving plate 2 and the drive base plate 4 can be improved, further enhancing the horizontal stability of the ejector pin moving plate 2. For example, assuming uneven force distribution on the ejector pin moving plate 2, the support of multiple calibration base plates 3 and elastic supports makes it difficult for the ejector pin moving plate 2 to undergo significant deformation, minimizing the displacement of the ejector pins 8 on the ejector pin moving plate 2.

[0034] Furthermore, multiple ejector pins 8 are vertically arranged on the upper surface of the ejector pin moving plate 2. One end of each ejector pin 8 is fixedly mounted on the upper surface of the ejector pin moving plate 2, and the other end of the ejector pin 8 passes through the corresponding ejector pin through hole on the support mechanism. When the ejector pin structure is working normally, the ejector pin moving plate 2 can drive the ejector pins 8 to move upward or downward within the ejector pin through hole. It should be noted that when moving upward, the tip of the ejector pin can pass through the ejector pin through hole to receive the wafer. When moving downward, the tip of the ejector pin can be hidden within the corresponding ejector pin through hole at most, and will not move out of the corresponding ejector pin through hole, to ensure that the ejector pin 8 is in a normal working state.

[0035] A driver 9 is mounted on the drive base plate 4. Through holes are also provided at corresponding positions on all calibration substrates 3. The drive shaft 10 of the driver 9 passes through the through holes on all calibration substrates 3 and is fixedly connected to the ejector pin moving plate 2 to provide drive for the ejector pin moving plate 2. That is, when the driver 9 drives the drive shaft 10 to move, the drive shaft 10 drives all ejector pins 8 to move via the ejector pin moving plate 2, causing all ejector pins 8 to move upwards or downwards within their corresponding ejector pin through holes.

[0036] In one embodiment, the driver 9 can be configured as a motor, in which case the drive shaft 10 is the motor shaft.

[0037] In one embodiment, multiple drivers 9 can be configured, and during configuration, the drive shafts 10 of the multiple drivers 9 can be uniformly fixed on the lower surface of the ejector pin moving plate 2. This ensures that the ejector pin moving plate 2 receives a uniform driving force, preventing the ejector pin moving plate 2 from tilting due to different driving forces.

[0038] In one embodiment, in order to reduce costs and reduce the size of the ejector pin structure, the driver 9 may be set to only one. In this case, in order to ensure that the ejector pin moving plate 2 is subjected to uniform driving force as much as possible, the drive shaft 10 of the driver 9 can be fixed at the center position of the ejector pin moving plate 2.

[0039] In one embodiment, reference is made to Figure 3 As shown, the support mechanism may specifically include a support platform 1 (i.e., an electrostatic chuck) and a filter chamber 11 disposed below the support platform 1. The support platform 1 is used to support the wafer during the reaction, while the filter chamber 11 provides support for the support platform 1. Since the reaction chamber is usually a vacuum environment and very clean, the filter chamber 11 can also protect the ejector pins 8 entering the reaction chamber, preventing them from being contaminated externally and bringing contaminants into the reaction chamber during their vertical movement, thus preventing contamination of the wafer. The ejector pin through-hole is provided through the support platform 1 and the filter chamber 11, and a clamping member 5 can also be installed inside the filter chamber 11, which is fitted onto the ejector pins 8. That is, each ejector pin 8 inside the filter chamber 11 is fitted with a clamping member 5. The clamping member 5 can keep the ejector pins 8 in a vertical position as much as possible to avoid friction between the ejector pins 8 and the ejector pin through-hole.

[0040] In one embodiment, a clamping component 5 may also be provided on the motor shaft between the calibration substrate 3 and the drive base plate 4. It plays a certain corrective role in the vertical movement of the motor shaft, and tries to avoid the problem of slight tilting of the ejector pin 8 caused by slight tilting of the motor shaft due to internal motor or installation.

[0041] Preferably, the clamping member 5 can be specifically configured as including a sleeve 7 and a sealing ring 6 disposed on the upper end of the sleeve 7, wherein the radius of the sleeve is set slightly larger than the radius of the ejector pin, and slightly smaller than the radius of the ejector pin through hole or the calibration through hole. The radius of the sealing ring 6 can be set between the radius of the ejector pin and the radius of the sleeve, so as to filter contaminants on the surface of the ejector pin 8 or the surface of the motor shaft. During installation, in order to achieve the filtering function, the clamping member 5 can be fixed in the upper surface of the filter cavity 11, and the clamping member 5 can be fixed between the calibration base plate 3 and the drive base plate 4, and fixed in the lower surface of the corresponding calibration base plate 3. It should be noted that the clamping member 5 can also be configured with other suitable structures, and there are no restrictions on its fixed configuration here.

[0042] In one embodiment, reference is made to Figure 3As shown, the needle drive mechanism may also include a level monitor to monitor the horizontal status of the ejector pin moving plate 2. Specifically, the level monitor may include a signal reflector 13 vertically mounted on the ejector pin moving plate 2 and a signal transceiver 12 mounted on one side of the ejector pin moving plate 2. The signal transmission paths of the signal reflector 13 and the signal transceiver 12 must satisfy the following: when the ejector pin moving plate 2 is horizontal, the signal transceiver 12 can receive the reflected signal reflected by the signal reflector 13, while when the ejector pin moving plate 2 is tilted, the signal transceiver 12 cannot receive the reflected signal reflected by the signal reflector 13. For example, the transmitting end and receiving end of the signal transceiver 12 can be set at a certain distance, and the signal can be sent to the signal reflector 13 at a certain angle, so that when the ejector pin moving plate 2 is set horizontally, the signal reflector 13 can just return the signal at a fixed angle, and the receiving end of the signal transceiver 12 can receive the signal; however, if the ejector pin moving plate 2 is tilted to a certain extent, the signal reflector 13 will also move at an angle, and the angle of the returned signal will change accordingly. At this time, the receiving end of the signal transceiver 12 will fail to receive the signal, and a warning signal will be issued.

[0043] In one embodiment, the needle drive mechanism may also include an alarm connected to a level monitor. When the level monitor detects a warning signal, it can send an alarm signal to the alarm, allowing staff to address the issue promptly. In other words, staff can monitor the level of the ejector pin moving plate 2 in real time using the level monitor and alarm, thus promptly identifying the cause of wafer defects and reducing the complexity and difficulty of the wafer defect determination process.

[0044] The uniformly stressed ejector pin structure provided in this embodiment improves the horizontal stability between the ejector pin moving plate and the drive base plate by setting one or more calibration substrates between them, minimizing tilting of the ejector pin moving plate during movement. Clamping components are fitted onto the ejector pins and motor shafts to ensure they are vertical relative to the corresponding through holes, reducing friction between them. The uniform distribution of driving forces on the ejector pin moving plate by evenly distributing the drive shafts of multiple drivers under the ejector pin moving plate or placing them at the center of the plate further reduces the possibility of tilting. Finally, a level monitoring device is installed on the ejector pin moving plate to monitor its horizontal state in real time. This allows operators to promptly identify the causes of wafer defects based on the monitoring data, reducing the complexity and difficulty of the wafer defect determination process.

[0045] like Figure 4As shown, this embodiment also provides an electrostatic chuck, specifically including the uniformly stressed ejector pin structure as described above. The electrostatic chuck employing the uniformly stressed ejector pin structure can improve wafer yield and reduce wafer defects caused by problems with the ejector pin structure.

[0046] Although the embodiments disclosed in this utility model are as described above, the content described is merely for the purpose of facilitating understanding of this utility model and is not intended to limit this utility model. Any person skilled in the art to which this utility model pertains may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in this utility model, but the protection scope of this utility model shall still be determined by the scope defined in the appended claims.

Claims

1. A uniformly stressed ejector pin structure, characterized in that, It includes a support mechanism and a pin drive mechanism disposed below the support mechanism; the support mechanism is provided with a plurality of pin through holes corresponding one-to-one with the pins; The ejector pin driving mechanism includes an ejector pin moving plate, at least one calibration base plate, and a driving base plate connected sequentially from top to bottom via elastic support columns. The ejector pin moving plate is provided with a plurality of ejector pins, one end of which is fixed to the upper surface of the ejector pin moving plate, and the other end of which passes through the corresponding ejector pin through hole. The driving base plate is provided with at least one driver, and the driving shaft of the driver passes through all the calibration base plates and is fixedly connected to the ejector pin moving plate. When the driver drives the drive shaft to move, the drive shaft drives all the ejector pins to move upward or downward in their corresponding ejector pin through holes via the ejector pin moving plate.

2. The uniformly stressed ejector pin structure according to claim 1, characterized in that, The supporting mechanism includes a supporting platform and a filter chamber disposed under the supporting platform. The ejector pin through hole penetrates the supporting platform and the filter chamber. A clamping member fitted onto the ejector pin is disposed inside the filter chamber.

3. The uniformly stressed ejector pin structure according to claim 1, characterized in that, The driver is a motor, and the drive shaft is a motor shaft.

4. The uniformly stressed ejector pin structure according to claim 3, characterized in that, There are multiple drivers, and the drive shafts of the multiple drivers are evenly fixed on the ejector pin moving plate.

5. The uniformly stressed ejector pin structure according to claim 3, characterized in that, There is one driver, and the drive shaft of the driver is fixed at the center position of the ejector pin moving plate.

6. The uniformly stressed ejector pin structure according to claim 3, characterized in that, A clamping component is fitted onto the motor shaft between the calibration substrate and the drive base plate.

7. The uniformly stressed ejector pin structure according to claim 2, characterized in that, The clamping member includes a sleeve and a sealing ring disposed on the upper end of the sleeve, and the clamping member is fixed to the upper surface of the filter chamber.

8. The uniformly stressed ejector pin structure according to claim 6, characterized in that, The clamping member includes a sleeve and a sealing ring disposed on the upper end of the sleeve, and the clamping member is fixed to the lower surface of the calibration substrate.

9. The uniformly stressed ejector pin structure according to claim 1, characterized in that, The ejector driving mechanism also includes a level monitor, which includes a signal reflector vertically mounted on the ejector moving plate and a signal transceiver mounted on one side of the ejector moving plate. When the ejector moving plate is horizontal, the signal transceiver can receive the reflected signal reflected by the signal reflector. When the ejector moving plate is tilted, the signal transceiver cannot receive the reflected signal reflected by the signal reflector.

10. The uniformly stressed ejector pin structure according to claim 9, characterized in that, The pin drive mechanism also includes an alarm connected to the level monitor.

11. An electrostatic chuck, characterized in that, Includes a uniformly stressed ejector pin structure as described in any one of claims 1-10.

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