Wafer clamping mechanism and four-probe resistance measuring device
By designing multi-level limiting and control components, the same wafer clamping mechanism can be adapted to wafers of different diameters, solving the problem of insufficient applicability of the stage limiting structure in the existing technology, improving work efficiency and reducing labor intensity.
Patent Information
- Application Number
- CN202520471950.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2026-02-10
- Estimated Expiration
- 2035-03-18
AI Technical Summary
Existing stage limiting structures can only limit wafers of a single diameter, and cannot adapt to wafers of different diameters, resulting in the need for frequent stage replacements, low work efficiency, and high labor intensity.
A wafer clamping mechanism was designed, which adopts a multi-level limiting component and a control component. The control component independently drives each level of the limiting component to switch between working and standby states, thereby achieving radial limiting of wafers of different diameters and adapting to various wafer specifications.
This improves the applicability of the wafer clamping mechanism, reduces the number of times the stage needs to be changed manually, increases work efficiency, and reduces labor intensity.
Smart Images
Figure CN223899686U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of semiconductor processing equipment technology, and in particular to a wafer clamping mechanism and a four-probe resistance measuring device. Background Technology
[0002] During wafer fabrication, resistivity testing is necessary to ensure product quality. To perform resistivity testing, the wafer is first placed on a stage, and a limiting structure on the stage is used to radially restrict its movement. This prevents the wafer from radially shifting relative to the stage during subsequent testing, ensuring the proper functioning of the test probes.
[0003] Existing stage-mounted limiting structures can only limit wafers of a single diameter. However, during wafer manufacturing, wafers of different diameters are produced according to actual needs, and a single stage cannot limit wafers of different diameters. Therefore, it is necessary to repeatedly change stages to meet the limiting requirements for wafers of different diameters. The disassembly and replacement of stages must be done manually by workers, which is not only inefficient but also labor-intensive and prone to fatigue. Utility Model Content
[0004] The purpose of this invention is to provide a wafer clamping mechanism and a four-probe resistance measuring device to limit the movement of wafers with different diameters and meet actual limiting requirements.
[0005] To achieve this objective, the present invention adopts the following technical solution:
[0006] Wafer clamping mechanism, including:
[0007] A stage for supporting a wafer, wherein the center of the stage coincides with the center of the wafer;
[0008] The multi-level limiting components and control components are arranged sequentially on circles of different radii with the center of the stage as the center. Each level of the limiting components is used to limit one of a variety of wafers with different diameters.
[0009] The control component is independently connected to each of the limiting components to drive each limiting component to switch independently between a working state and a standby state. The limiting component in the working state can radially limit and support the wafer on the stage, while the other limiting components in the standby state do not interfere with the wafer supported on the stage.
[0010] Alternatively, each level of the limiting component includes: at least two abutting members, each abutting member falling on a circumference of the same radius centered on the center of the platform; and
[0011] At least two driving elements are provided, each of which has an output terminal electrically connected to one of the abutment elements to drive the corresponding abutment element to switch between the working state and the standby state. The abutment element in the working state can abut against the wafer in the radial direction, while the abutment element in the standby state does not interfere with the wafer.
[0012] As an optional solution, the platform is provided with multiple sets of through holes, each set of through holes is corresponding to a set of limiting components, each set of through holes includes at least two through holes on a circumference with the center of the platform as the center and located on the same radius, each through hole penetrates the platform in the vertical direction, and each through hole is provided with an abutment member.
[0013] The driving member can drive the corresponding abutment to extend or retract from the upper surface of the platform through the corresponding through hole.
[0014] As an optional feature, the angle between the radial line connecting two adjacent through holes in each group and the center of the platform shall be no less than 45° and no more than 135°.
[0015] As an optional feature, the surface of the abutment is covered with an elastic cushioning layer.
[0016] As an optional solution, the platform is provided with a feeding port, and the feeding port is provided with a multi-stage conveying recess extending radially with the platform as the center. The multi-stage conveying recess is used to accommodate the feeding hand for clamping the wafer, and the multi-stage conveying recess can accommodate at least two different sizes of feeding hands.
[0017] As an optional solution
[0018] The stage is provided with multiple levels of annular air channels, which are arranged sequentially on circles of different radii with the center of the stage as the center. Each level of the annular air channel is used to adsorb and fix one of a variety of wafers with different diameters.
[0019] As an optional solution, the wafer clamping mechanism further includes:
[0020] The negative pressure power source and connecting pipes, each of the annular air passages is independently connected to the negative pressure power source through its own connecting pipe.
[0021] As an optional solution, the wafer clamping mechanism further includes:
[0022] The control platform is communicatively connected to the control component. The control platform is equipped with multiple control buttons, each of which corresponds to a first-level limit component. The control buttons can switch between a pressed state and a reset state. The pressed state corresponds to the working state of the limit component, and the reset state corresponds to the standby state of the limit component.
[0023] The four-probe resistance testing device includes a transfer mechanism, a probe mechanism, a transport mechanism, and a wafer clamping mechanism as described above. The transport mechanism is configured to load and unload wafers to feed and remove them from the stage. The probe mechanism is mounted on the transfer mechanism and is configured to measure the resistivity of the wafer. The transfer mechanism is configured to drive the probe mechanism to move relative to the wafer.
[0024] The beneficial effects of this utility model are:
[0025] The wafer clamping mechanism provided by this utility model, by setting up multi-level limiting components, enables each level of limiting component to limit one of multiple wafers with different diameters. The control component drives each level of limiting component to switch between a working state of radially limiting the wafer and a standby state where it does not interfere with the wafer. When one of multiple wafers with different diameters is coaxially supported on the stage, the control component can drive the corresponding limiting component to the working state according to the actual diameter of the wafer supported on the stage, and drive the other limiting components to the standby state, so as to achieve radial limiting of the wafer of that diameter. This enables the same wafer clamping mechanism to adapt to the clamping requirements of multiple wafers of different sizes, improves the usability of the wafer clamping mechanism, avoids multiple manual replacements by the operator, improves work efficiency, and reduces labor intensity.
[0026] This invention also provides a four-probe resistance measuring device. By applying the above-mentioned wafer clamping mechanism, radial positioning of various wafers with different diameters can be achieved, thereby improving the efficiency of subsequent resistivity measurement of the wafers. Attached Figure Description
[0027] Figure 1 This is a first structural schematic diagram of the wafer clamping mechanism provided in this embodiment of the present invention;
[0028] Figure 2 This is a schematic diagram of the second structure of the wafer clamping mechanism provided in this embodiment of the present invention;
[0029] Figure 3 This is a cross-sectional schematic diagram of the wafer clamping mechanism provided in an embodiment of the present utility model;
[0030] Figure 4 yes Figure 3A magnified view of a portion of point A in the middle.
[0031] In the picture:
[0032] 100. First-level limiting component; 110. First abutment component; 120. First driving component;
[0033] 200. Second-level limit component;
[0034] 300. Third-level limit component;
[0035] 400, Platform; 410, Feeding port; 411, Multi-stage conveying notch; 420, Through hole; 430, Through hole. Detailed Implementation
[0036] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.
[0037] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0038] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0039] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.
[0040] When performing resistivity testing on wafers, the wafer must first be placed on a stage, and the stage's limiting structure must radially restrain the wafer to prevent radial displacement relative to the stage during subsequent testing, ensuring the normal operation of the test probes. Existing stage limiting structures can only restrain wafers of a single diameter. However, during wafer manufacturing, wafers of different diameters are produced according to actual needs, and a single stage cannot provide radial restraint for wafers of varying diameters. Therefore, it is necessary to repeatedly change stages to meet the radial restraint requirements for wafers of different diameters. The disassembly and replacement of stages require manual operation by staff, which is not only inefficient but also physically demanding and prone to fatigue.
[0041] To solve the above problems, such as Figures 1-3 As shown, this embodiment provides a wafer clamping mechanism. The wafer clamping mechanism includes multi-level limiting components, a control component, and a stage 400. The stage 400 supports the wafer, and its center coincides with the center of the wafer. The multi-level limiting components are arranged sequentially on circles of different radii with the center of the stage 400 as the center. Each limiting component is used to limit one type of wafer with different diameters. The control component is independently communicatively connected to each limiting component to drive each limiting component to switch between an active state and a standby state. In the active state, the limiting component can radially limit the wafer supported on the stage 400. In the standby state, the limiting component does not interfere with the wafer supported on the stage 400.
[0042] This wafer clamping mechanism incorporates multiple levels of limiting components, each capable of clamping one type of wafer with different diameters. A control component drives each limiting component to switch between a radially clamping state and a standby state where it does not interfere with the wafer. When one type of wafer with different diameters is supported on the stage 400, the control component activates the corresponding limiting component based on the actual diameter of the wafer on the stage 400, while keeping the remaining limiting components in standby mode. This achieves radial clamping of the wafer of that diameter, enabling the same wafer clamping mechanism to accommodate the clamping requirements of multiple wafers of different sizes. This improves the usability of the wafer clamping mechanism, avoids multiple manual replacements by operators, increases work efficiency, and reduces labor intensity.
[0043] In this embodiment, the technical solution is illustrated using wafers of 6-inch, 8-inch, and 12-inch sizes as examples. The multi-level limiting components in this embodiment include a first-level limiting component 100, a second-level limiting component 200, and a third-level limiting component 300. These components are arranged radially outwards from the end closest to the center of the stage 400. The third-level limiting component 300 can radially limit a 6-inch diameter wafer, the second-level limiting component 200 can radially limit an 8-inch diameter wafer, and the first-level limiting component 100 can radially limit a 12-inch diameter wafer. In other embodiments, the number of limiting components can be adaptively adjusted according to the number of wafers of different sizes; this embodiment does not impose specific limitations.
[0044] To facilitate the switching between working and standby states of the first-level limiting component 100, the second-level limiting component 200, and the third-level limiting component 300, the wafer clamping mechanism also includes a control platform. The control platform is communicatively connected to the control component and has three control buttons. These three control buttons correspond to the first-level limiting component 100, the second-level limiting component 200, and the third-level limiting component 300, respectively. The control buttons can switch between a pressed state and a reset state. The pressed state of the control button corresponds to the working state of the corresponding first-level limiting component 100, the second-level limiting component 200, and the third-level limiting component 300, while the reset state corresponds to the standby state of the corresponding first-level limiting component 100, the second-level limiting component 200, and the third-level limiting component 300. When the first-level limiting component 100 is needed to limit the wafer, the control button corresponding to the first-level limiting component 100 is pressed, and the other two control buttons are reset. When the second-level limiting component 200 is needed to limit the wafer, the control button corresponding to the second-level limiting component 200 is pressed, and the other two control buttons are reset. When the third-level limiting component 300 is needed to limit the wafer, the control button corresponding to the third-level limiting component 300 is pressed, and the other two control buttons are reset.
[0045] It should be noted that the specific structure and working principle of the control platform and control components are existing technologies and will not be elaborated here.
[0046] In actual operation, wafers need to be repeatedly placed on and removed from the stage 400. To facilitate the storage and retrieval of wafers relative to the stage 400, such as... Figure 1 As shown, the upper surface of the stage 400 includes a feeding port 410, through which wafers are fed onto the stage 400. When a wafer of a certain size needs to be fed onto the stage 400, the corresponding limiting component is driven to the working state according to the diameter of the wafer, and then the wafer is fed into the stage 400 from the feeding port 410, and the wafer is made to abut against the corresponding limiting component, thus realizing the wafer loading operation relative to the stage 400.
[0047] like Figure 1As shown, this embodiment provides a feeding port 410 that can adapt to different feeding components. It includes a multi-stage conveying recess 411 extending radially from the center of the stage 400. The feeding hand responsible for clamping and fixing the wafer within the feeding mechanism can move along the multi-stage conveying recess 411 to convey the wafer on the surface of the feeding hand to the stage 400. The multi-stage conveying recess 411 can accommodate at least two sizes of feeding hands. Understandably, in this embodiment, taking wafers with 6-inch, 8-inch, and 12-inch sizes as examples, the feeding hand within the feeding mechanism should be adapted to different sizes of feeding hands to ensure effective clamping and fixing of the wafers of different sizes. Furthermore, the larger the diameter of the wafer, the larger the size of the corresponding feeding hand. To ensure that feeding hands of different specifications can move along the multi-stage conveying recess 411, the multi-stage conveying recess 411 is a stepped structure with a stepped width. The width of the multi-stage conveying recess 411 gradually increases as it extends radially from the end near the center of the platform 400 to the end away from the center of the platform 400, so as to accommodate feeding hands of different specifications at the same time.
[0048] This embodiment provides a possible specific structure of a limiting component. Those skilled in the art can adjust this scheme through simple modifications, therefore the scope of protection of this application is not limited thereto.
[0049] Combination Figure 3 and Figure 4 The specific structure of the first-level limiting component 100 in this embodiment will be described. The first-level limiting component 100 includes two first abutting members 110 and two first driving members 120. The two first abutting members 110 are both located on a circle with the same radius centered on the center of the stage 400. The output terminal of each first driving member 120 is electrically connected to one of the first abutting members 110 to drive the corresponding first abutting member 110 to switch between a working state and a standby state. The first abutting member 110 in the working state can abut against the wafer radially, while the first abutting member 110 in the standby state does not interfere with the wafer, thereby achieving radial limiting of the wafer.
[0050] It should be noted that in other embodiments, the first-level limiting component 100 may also include three or more first abutting members 110 and first driving members 120, while ensuring that the number and position of the through holes 430 corresponding to the first-level limiting component 100 are adapted to the number of first abutting members 110. This embodiment does not make specific limitations.
[0051] Furthermore, in this embodiment, the first driving element 120 is a linear cylinder. In other embodiments, the first driving element 120 may also be a linear motor or other linear drive structure; this embodiment does not impose specific limitations.
[0052] In this embodiment, the platform 400 is provided with three sets of through holes 430. Each set of through holes 430 is corresponding to a set of limiting components. Each set of through holes 430 includes two through holes 430 on a circumference with the center of the platform 400 as the center and located on the same radius. Each through hole 430 penetrates the platform 400 in the vertical direction. Each through hole 430 is provided with a first abutting member 110. The first driving member 120 can drive the corresponding first abutting member 110 to extend or retract from the upper end face of the platform 400 from the corresponding through hole 430, thereby improving the structural compactness of the first-level limiting component 100 and the platform 400. Understandably, since this embodiment is adapted to 6-inch, 8-inch, and 12-inch wafers, three or more sets of limiting holes are provided on the stage 400, arranged radially with the center of the stage 400 as the center. In other embodiments, the number of limiting holes on the stage 400 can be adjusted according to actual needs; this embodiment does not impose a specific limitation. To further improve the limiting effect of the two first abutting members 110 on the wafer, in this embodiment, the angle between the two through holes 430 corresponding to the first-level limiting component 100 and the radial line connecting the center of the stage 400 is 90°. In other embodiments, the angle between the two through holes 430 corresponding to the first-level limiting component 100 and the radial line connecting the center of the stage 400 can also be arbitrarily adjusted within a range of not less than 45° and not more than 135°, according to actual needs; this embodiment does not impose a specific limitation.
[0053] To further enhance wafer protection, the surface of the first abutment 110 is covered with an elastic buffer layer. It should be noted that in this embodiment, the elastic buffer layer is made of rubber. Rubber has good elasticity, toughness, and wear resistance, resulting in a long service life. In other embodiments, the elastic buffer groove may also be made of sponge, cotton, or other elastic materials; this embodiment does not impose specific limitations.
[0054] Understandably, the specific structure and tooling principle of the second-level limit component 200 and the third-level limit component 300 are the same as those of the first-level limit component 100. To keep the text concise, the specific structure and working principle of the second-level limit component 200 and the third-level limit component 300 will not be described in detail here.
[0055] In this embodiment, the stage 400 has a first-stage annular air channel, a second-stage annular air channel, and a third-stage annular air channel. These three annular air channels are arranged radially around the center of the stage 400. The first-stage annular air channel is used to adsorb and fix wafers with a diameter of 12 inches, the second-stage annular air channel is used to adsorb and fix wafers with a diameter of 8 inches, and the third-stage annular air channel is used to adsorb and fix wafers with a diameter of 6 inches, thus achieving stable clamping and fixation of the wafer to the stage 400. Furthermore, the annular air channels can apply a uniform adsorption force to the wafer, improving wafer protection.
[0056] Optionally, the wafer-shaped structure includes a negative pressure power source and connecting pipes. The first-stage annular air passage, the second-stage annular air passage, and the third-stage annular air passage are independently connected to the negative pressure power source through their respective connecting pipes. It should be noted that, in this embodiment, as... Figure 1 As shown, the first-stage annular airway, the second-stage annular airway, and the third-stage annular airway are each provided with a through hole 420. The first-stage annular airway, the second-stage annular airway, and the third-stage annular airway are connected to their respective connecting pipes and negative pressure power sources through the through holes 420, so that the negative pressure power source provides a negative pressure environment for the first-stage annular airway, the second-stage annular airway, and the third-stage annular airway.
[0057] When a 12-inch diameter wafer is radially positioned on the stage 400, the negative pressure power source maintains a negative pressure state in the first-stage annular air passage, thereby adsorbing and fixing the wafer onto the stage 400. It should be noted that in this embodiment, the negative pressure power source is a vacuum pump. Vacuum pumps are highly responsive, easy to install and disassemble, and have stable output power.
[0058] Furthermore, in this embodiment, the first annular air channel, the second annular air channel, and the third annular air channel share the same negative pressure power source. The wafer clamping mechanism also includes three sealing plugs, which respectively seal the through holes 420 within the first annular air channel, the second annular air channel, and the third annular air channel. When the first annular air channel is needed to adsorb and fix the wafer, the sealing plug in the through hole 420 corresponding to the first annular air channel is removed, and the through holes 420 corresponding to the second and third annular air channels are sealed with sealing plugs. In other embodiments, the first annular air channel, the second annular air channel, and the third annular air channel may each be associated with a negative pressure power source; this embodiment does not impose specific limitations.
[0059] This embodiment also provides a four-probe resistance testing device. The four-probe resistance testing device includes a transfer mechanism, a probe mechanism, and the aforementioned wafer clamping mechanism. The probe mechanism is mounted on the transfer assembly and is configured to measure the resistivity of the wafer. The transfer mechanism is configured to drive the probe mechanism to move relative to the wafer. This four-probe resistance measuring device, by applying the aforementioned wafer clamping mechanism, can achieve radial clamping and fixing of various wafers with different diameters, improving the efficiency of subsequent wafer resistivity measurement. It should be noted that the specific structure and working principle of the transfer mechanism and the probe mechanism are existing technologies and will not be described in detail here.
[0060] To further improve the efficiency of wafer resistivity testing, the four-probe resistance testing device also includes a handling mechanism. This mechanism is configured to load and unload wafers, feeding them into and removing them from the stage 400. The specific structure and tooling principle of the handling mechanism are existing technologies and will not be described in detail here.
[0061] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.
Claims
1. A wafer clamping mechanism, characterized in that, include: A stage (400) for supporting a wafer, the center of which coincides with the center of the wafer; The multi-level limiting components and control components are arranged sequentially on circles of different radii with the center of the stage (400) as the center. Each level of the limiting components is used to limit one of a variety of wafers with different diameters. The control component is independently connected to each of the limiting components to drive each limiting component to switch independently between working state and standby state. The limiting component in the working state can radially limit the wafer supported on the stage (400). The other limiting components in the standby state do not interfere with the wafer supported on the stage (400).
2. The wafer clamping mechanism according to claim 1, characterized in that, Each level of the limiting assembly includes: at least two abutments, each abutment falling on a circumference of the same radius centered on the center of the platform (400); and At least two driving elements are provided, each of which has an output terminal electrically connected to one of the abutment elements to drive the corresponding abutment element to switch between the working state and the standby state. The abutment element in the working state can abut against the wafer in the radial direction, while the abutment element in the standby state does not interfere with the wafer.
3. The wafer clamping mechanism according to claim 2, characterized in that, The platform (400) has multiple sets of through holes (430), each set of through holes (430) is corresponding to a set of limiting components, each set of through holes (430) includes at least two through holes (430) on a circumference with the center of the platform (400) as the center and located on the same radius, each through hole (430) penetrates the platform (400) in the vertical direction, and each through hole (430) is provided with an abutment member; The driving member can drive the corresponding abutment to extend or retract from the upper surface of the platform (400) from the corresponding through hole (430).
4. The wafer clamping mechanism according to claim 3, characterized in that, The included angle between the radial lines connecting two adjacent through holes (430) in each group and the center of the platform (400) is not less than 45° and not greater than 135°.
5. The wafer clamping mechanism according to claim 2, characterized in that, The surface of the abutment is covered with an elastic buffer layer.
6. The wafer clamping mechanism according to any one of claims 1 to 5, characterized in that, The stage (400) is provided with a feeding port (410), and the feeding port (410) is provided with a multi-stage conveying recess (411) extending radially with the stage (400) as the center. The multi-stage conveying recess (411) is used to accommodate the feeding hand for clamping the wafer, and the multi-stage conveying recess (411) can accommodate at least two different sizes of feeding hands.
7. The wafer clamping mechanism according to any one of claims 1 to 5, characterized in that, The stage (400) is provided with multiple levels of annular air channels. The multiple levels of annular air channels are arranged in sequence on circles of different radii with the center of the stage (400) as the center. Each level of annular air channel is used to adsorb and fix one of a variety of wafers with different diameters.
8. The wafer clamping mechanism according to claim 7, characterized in that, The wafer clamping mechanism further includes: The negative pressure power source and connecting pipes, each of the annular air passages is independently connected to the negative pressure power source through its own connecting pipe.
9. The wafer clamping mechanism according to any one of claims 1 to 5, characterized in that, The wafer clamping mechanism further includes: The control platform is communicatively connected to the control component. The control platform is equipped with multiple control buttons, each of which corresponds to a first-level limit component. The control buttons can switch between a pressed state and a reset state. The pressed state corresponds to the working state of the limit component, and the reset state corresponds to the standby state of the limit component.
10. A four-probe resistance testing device, characterized in that, The device includes a transfer mechanism, a probe mechanism, a transport mechanism, and a wafer clamping mechanism as described in any one of claims 1 to 9, wherein the transport mechanism is configured to load and unload wafers to feed and remove wafers from the stage (400); the probe mechanism is mounted on the transfer mechanism and is configured to measure the resistivity of the wafer; the transfer mechanism is configured to drive the probe mechanism to move relative to the wafer.