Chip stress calibration device and calibration method

Abstract

The invention discloses a chip stress calibration device and calibration method, and relates to the technical field of microelectronic device testing, the chip stress calibration device comprises a base, a bearing table, a pressure applying assembly, a driving assembly, a pressure sensor and an electric signal measuring element; wherein the bearing table is fixedly arranged on the base, the bearing table is used for bearing a chip, a limiting structure is arranged on the bearing table, and the limiting structure is provided with a limiting surface for limiting the chip; the pressure applying assembly is movably arranged on the base, the pressure applying assembly is located at the end, away from the limiting structure, of the base, and the pressure applying assembly is provided with a pressure applying face used for making contact with the side wall of the chip and applying acting force close to the limiting structure to the chip; the driving assembly is arranged on the base and used for driving the pressure applying assembly to move in the direction parallel to the upper surface of the base. The pressure sensor is connected with the pressure applying assembly and is used for detecting the acting force applied to the chip by the pressure applying assembly; the electric signal measuring element is used for being electrically connected with the chip so as to monitor electric signal changes of the chip.

Description

Technical Field

[0001] This invention relates to the field of microelectronic device testing technology, specifically to a chip stress calibration device and calibration method. Background Technology

[0002] As the integration level of chips or microsystems increases, a series of failure issues may occur due to mechanical and thermal stresses generated in the chip's packaging structure or packaging integration process, as well as under operating conditions, such as silicon interposer breakage and stacked chip breakage. Therefore, stress sensing elements are needed to test the stress at the packaging interface, and the stress test data feedback can be used to optimize the chip packaging or microsystem integration structure or packaging process.

[0003] Stress sensing elements typically output electrical signals, therefore, they need to be calibrated first. The principle is to establish a correlation between the magnitude of the output signal and the applied known stress by relating the change in the electrical signal of the stress sensing element. Existing stress application methods mainly include the three-point bending method and the four-point bending method. However, these methods apply pressure to the chip surface at one or two points to cause the chip to bend. The stress after bending can be calculated by calibrating the chip size and the distance between the fulcrums. The stress distribution is significantly affected by the fulcrum spacing and chip size, resulting in a large error in the calculated stress and reduced calibration accuracy. Summary of the Invention

[0004] The purpose of this invention is to provide a chip stress calibration device and calibration method to solve the problem that the stress distribution applied to the chip is affected by the chip size, resulting in large calculation stress errors and reduced calibration accuracy when performing chip stress calibration.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] In a first aspect, the present invention provides a chip stress calibration device, comprising:

[0007] Base;

[0008] A support platform is fixedly mounted on a base. The support platform is used to support the chip. A limiting structure is provided on the support platform. The limiting structure has a limiting surface for limiting the chip.

[0009] The pressure application component is movably disposed on the base. The pressure application component is located at one end of the base away from the limiting structure. The pressure application component has a pressure application surface for contacting the sidewall of the chip and applying a force to the chip close to the limiting structure.

[0010] A drive assembly is disposed on the base and is used to drive the pressure application assembly to move in a direction parallel to the upper surface of the base;

[0011] A pressure sensor, connected to a pressure application component, is used to detect the pressure applied to the chip by the pressure application component;

[0012] Electrical signal measuring elements are used to electrically connect to a chip to monitor changes in the chip's electrical signals.

[0013] Compared with the prior art, the chip stress calibration device provided in this application uses a base as the overall support foundation, a support platform fixedly set on the base surface for placing the chip, and a limiting structure set on the support platform closely adhering to the chip sidewall to achieve chip positioning and force application, ensuring that the chip will not move during the force application process and affect the stress calculation; the pressure application component is located on the base at one end away from the limiting structure and is movable along a direction parallel to the base surface. The pressure application component can move on the base to contact the other sidewall of the chip and apply a force close to the limiting structure to the sidewall of the chip; the driving component is set on the base and is used to drive the pressure application component to move along a direction parallel to the upper surface of the base; the pressure sensor is connected to the pressure application component to detect the applied force value; and the electrical signal measuring element contacts the chip surface to monitor changes in the chip's electrical signal. During operation: The drive component moves the pressure application component on the base toward the support platform on which the chip is placed, causing the pressure surface to contact one sidewall of the chip and apply a pushing force to the sidewall, pushing the chip to adhere to the limiting surface of the limiting structure, forming a stress field on the chip surface; the pressure sensor simultaneously outputs the applied force data, and the actual stress value is calculated by combining it with the chip's cross-sectional area; the electrical signal measurement element collects changes in the electrical signal on the chip in real time, realizing dynamic correlation calibration between stress and electrical signal. This setup allows for the adaptation of chips of any size by adhering the chip to the limiting structure, avoiding the chip size limitations caused by the fixed fulcrum spacing of traditional three-point bending or four-point bending methods; and the force direction parallel to the chip surface eliminates the drawbacks of uneven stress distribution caused by the traditional force applied perpendicular to the chip surface, improving calibration accuracy.

[0014] Optionally, in the above-mentioned chip stress calibration device, the driving component includes:

[0015] The first drive motor is fixedly mounted on the base;

[0016] The first drive screw has its axis parallel to the upper surface of the base. One end of the first drive screw is rotatably connected to the base, and the other end of the first drive screw is connected to the drive end of the first drive motor. The pressure application component is disposed on the base and threadedly engaged with the first drive screw.

[0017] Optionally, in the above-mentioned chip stress calibration device, a first slide rail is also provided on the base, the extension direction of the first slide rail is parallel to the upper surface of the base, and the pressure application component is guided and connected to the first slide rail.

[0018] Optionally, in the above-mentioned chip stress calibration device, the pressure application component includes:

[0019] The bracket is movable on the base in a direction parallel to the surface of the base;

[0020] The second drive motor is fixedly mounted on the bracket.

[0021] The second drive screw has its axis perpendicular to the upper surface of the base. One end of the second drive screw is rotatably connected to the bracket, and the other end of the second drive screw is connected to the drive end of the second drive motor.

[0022] The pressure-applying component is mounted on the bracket and threaded to the second drive screw. The pressure sensor is connected to the pressure-applying component to detect the force applied by the pressure-applying component.

[0023] Optionally, in the above-mentioned chip stress calibration device, the pressure-applying component includes:

[0024] A support platform is mounted on a bracket and threadedly connected to a second drive screw. A pressure sensor is fixedly connected to the support platform.

[0025] The cantilever includes a first part and a second part that are fixed to each other. The first part is parallel to the upper surface of the base, and the second part is perpendicular to the upper surface of the base. The first part is fixedly connected to the pressure sensor.

[0026] The pusher blade is fixedly connected to the second part and is used to contact the sidewall of the chip and apply force.

[0027] Optionally, in the above-mentioned chip stress calibration device, the support stage includes:

[0028] The substrate is fixedly mounted on the base.

[0029] A wafer carrier stage is fixedly mounted on a substrate and is used to place chips. The limiting structure includes a driving component and a pushing component, and the pushing component has a portion that moves horizontally on the surface of the wafer carrier stage.

[0030] Optionally, in the above-mentioned chip stress calibration device, the driving component includes a third driving motor and a third driving screw. The third driving motor is fixedly mounted on the support platform, the axial direction of the third driving screw is parallel to the upper surface of the base, one end of the third driving screw is rotatably connected to the support platform, and the other end of the third driving screw is connected to the driving end of the third driving motor. The pushing component is threadedly engaged with the third driving screw, and the third driving screw is used to drive the pushing component to contact the chip.

[0031] The pushing component includes a push block and a stop block. The push block is threadedly connected to the third drive screw, and the stop block is slidably disposed on the wafer stage. The stop block is connected to one end of the push block and is used to limit contact with the end of the chip.

[0032] Optionally, in the chip stress calibration device described above, both the limiting surface of the limiting structure and the pressure surface of the pressure application component are provided with adhesives, which are used to bond and fix the chip to the sidewall.

[0033] Optionally, in the above-mentioned chip stress calibration device, the electrical signal measuring element includes two probes, and the chip stress calibration device also includes a controller. The controller is communicatively connected to the pressure sensor and the two probes, respectively. The two probes are used to contact the two pads of the chip surface stress sensing element.

[0034] Secondly, the present invention provides a chip stress calibration method, wherein the chip stress calibration method uses any of the above-mentioned chip stress calibration devices to perform stress calibration, and includes the following steps:

[0035] The chip is placed on the support stage, and one side wall of the chip contacts the limiting surface of the limiting structure of the support stage.

[0036] The pressure application component is moved to the other side of the chip by the driving component, so that the pressure application surface of the pressure application component contacts the other side wall of the chip;

[0037] A force is applied to the chip by a pressure-applying component;

[0038] The pressure data of the chip and the electrical signal of the electrical signal measuring element are collected synchronously through pressure sensors and electrical signal measuring elements.

[0039] The stress calibration of the chip is completed by associating pressure data and electrical signals.

[0040] Compared with the prior art, the beneficial effects of the chip stress calibration method provided in this application are the same as those of the chip stress calibration device described above, and will not be repeated here. Attached Figure Description

[0041] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0042] Figure 1 This is a schematic diagram of the overall structure of a chip stress calibration device proposed in an embodiment of the present invention;

[0043] Figure 2 This is a top view schematic diagram of a chip stress device proposed in an embodiment of the present invention.

[0044] Reference numerals: 100 is base, 200 is support platform, 210 is base body, 220 is substrate stage, 230 is limiting structure, 2301 is driving component, 23011 is third driving motor, 23012 is third driving screw, 2302 is pushing component, 23021 is push block, 23022 is stop block, 300 is pressure application component, 310 is bracket, 320 is second driving motor, 330 is second driving screw, 340 is pressure application component, 3401 is support platform, 3402 is cantilever, 3403 is push knife, 400 is driving component, 410 is first driving motor, 420 is first driving screw, 500 is pressure sensor, 600 is probe, 700 is first slide rail, 800 is chip. Detailed Implementation

[0045] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below 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 are not intended to limit the present invention.

[0046] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0047] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.

[0048] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, 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 invention.

[0049] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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 invention according to the specific circumstances.

[0050] Firstly, please refer to Figure 1 The chip stress calibration device provided in this embodiment of the invention includes: a base, a support platform, a pressure application component, a driving component, a pressure sensor, and an electrical signal measuring element; wherein, the support platform is fixedly disposed on the base, the support platform is used to support the chip, and a limiting structure is provided on the support platform, the limiting structure having a limiting surface for limiting the chip; the pressure application component is movably disposed on the base, the pressure application component is located at one end of the base away from the limiting structure, the pressure application component has a pressure application surface for contacting the sidewall of the chip and applying a force to the chip close to the limiting structure; the driving component is disposed on the base, and is used to drive the pressure application component to move in a direction parallel to the upper surface of the base; the pressure sensor is connected to the pressure application component, and is used to detect the pressure applied to the chip by the pressure application component; the electrical signal measuring element is used to be electrically connected to the chip to monitor changes in the chip's electrical signal.

[0051] In specific implementation: In the chip 800 stress calibration device provided in this application, the base 100 serves as the overall support foundation, and the support platform 200 is fixedly set on the surface of the base 100 for placing the chip 800. The limiting structure 230 set on the support platform 200 is in close contact with the side wall of the chip 800 to realize the positioning and force of the chip 800, ensuring that the chip 800 will not move during the force application process, thus affecting the stress calculation; the pressure application component 300 is located at the end of the base 100 away from the limiting structure 230, along the parallel surface of the base 100. The pressure application component 300 is configured to move on the base 100 to contact the other sidewall of the chip 800 and apply a force close to the limiting structure 230 to the sidewall of the chip 800. The driving component 400 is disposed on the base 100 and is used to drive the pressure application component 300 to move in a direction parallel to the upper surface of the base 100. The pressure sensor 500 is connected to the pressure application component 300 to detect the applied force value. The electrical signal measuring element contacts the surface of the chip 800 to monitor the changes in the electrical signal of the chip 800. During operation: the drive component 400 drives the pressure application component 300 to move on the base 100 toward the support platform 200 on which the chip 800 is placed, thereby contacting one side wall of the chip 800 and applying a pushing force to the side wall of the chip 800, pushing the chip 800 to adhere to the surface of the limiting structure 230, forming a stress field on the surface of the chip 800; the pressure sensor 500 synchronously outputs the applied force data, and calculates the actual stress value in combination with the cross-sectional area of ​​the chip 800; the electrical signal measuring element collects the changes in electrical signals on the chip 800 in real time, realizing dynamic correlation calibration between stress and electrical signals. With this setting, by adhering the chip 800 to the limiting structure 230, it can accommodate chips 800 of any size, avoiding the size limitations of the chip 800 caused by the fixed fulcrum spacing of the traditional three-point bending method or four-point bending method; and the force direction parallel to the surface of the chip 800 eliminates the drawbacks of uneven stress distribution caused by the traditional force applied perpendicular to the surface of the chip 800, improving calibration accuracy.

[0052] As one possible implementation, such as Figure 1 As shown, the drive assembly 400 includes a first drive motor 410 and a first drive screw 420; wherein, the first drive motor 410 is fixedly disposed on the base 100; the axial direction of the first drive screw 420 is parallel to the upper surface of the base 100, one end of the first drive screw 420 is rotatably connected to the base 100, and the other end of the first drive screw 420 is connected to the drive end of the first drive motor 410; the pressure application assembly 300 is disposed on the base 100 and threadedly engaged with the first drive screw 420.

[0053] As one possible implementation, such as Figure 1As shown, the drive assembly 400 includes a first drive motor 410 and a first drive screw 420; wherein, the first drive motor 410 is mounted and fixed on the side of the base 100; the first drive screw 420 is horizontally arranged and axially parallel to the upper surface of the base 100, one end of the first drive screw 420 is rotatably connected to a pre-set support on the base 100 through a bearing assembly, and the other end is connected to the output shaft of the first drive motor 410 through a coupling; the pressure application assembly 300 is disposed on the base 100 and has a threaded hole at the bottom, and engages with the first drive screw 420 through its threaded hole, allowing the first drive screw 420 and the base 100 to rotate relative to each other, and the pressure application assembly 300 converts the rotational motion of the first drive screw 420 into horizontal linear displacement through the threaded engagement. During operation, the chip 800 is placed at a specific position on the support platform 200. After the first drive motor 410 is started, it drives the first drive screw 420 to rotate. The pressure application component 300 moves horizontally along the screw axis, pushing the pressure application component 300 close to the chip 800 on the support platform 200 until it contacts the chip 800, thereby applying a thrust to the side wall of the chip 800. The applied thrust value is detected by the pressure sensor 500 connected to the pressure application component 300, and the change of electrical signal of the chip 800 is monitored by the electrical signal measuring element to achieve stress calibration of the chip 800.

[0054] In some embodiments, the drive assembly 400 is a hydraulic assembly, including a hydraulic cylinder disposed on the base 100 and a hydraulic rod parallel to the upper surface of the base 100. The pressure application assembly 300 is disposed on the base 100, and the pushing end of the hydraulic rod is connected to one end of the pressure application assembly 300, which can apply a force to the pressure application assembly 300 to move horizontally on the upper surface of the base 100.

[0055] As one possible implementation, a first slide rail 700 is also provided on the base 100. The extension direction of the first slide rail 700 is parallel to the upper surface of the base 100, and the pressure application component 300 is guided and connected to the first slide rail 700.

[0056] Specifically, the first slide rail 700 is fixed to the upper surface of the base 100 by bolts or integrally formed on the upper surface of the base 100, and its extension direction is parallel to the upper surface of the base 100. The bottom of the pressure application component 300 is provided with a slider structure, and the pressure application component 300 forms a sliding fit with the guide groove of the first slide rail 700 through the slider structure. In this structure, the first slide rail 700 is fixed to the surface of the base 100 as a rigid reference, and the pressure application component 300 is embedded in the guide groove of the slide rail through the slider to achieve horizontal movement constraint. During operation, when the drive component 400 pushes the pressure application component 300 to move horizontally, the slider integral with the pressure application component 300 slides along the guide groove of the first slide rail 700. The circumferential torque generated by the rotation of the first drive screw 420 on the pressure application component 300 is resisted by the groove wall of the guide groove contacting the side of the slider, ensuring that the pressure application component 300 only translates in a single direction and avoiding the deflection of the pusher 3403. With this configuration, the first slide rail 700 guides and eliminates radial offset during the movement of the pressure application component 300, ensuring that the pressure application component 300 can always be perpendicularly attached to the side wall of the chip 800; the guiding mechanism of the first slide rail 700 for the pressure application component 300 compensates for the fit clearance of the transmission system, improves the positioning accuracy of repeated displacements, and ensures that the experiment can be accurately and repeatedly implemented.

[0057] As one possible implementation, such as Figure 1 As shown, the pressure application assembly 300 includes a bracket 310, a second drive motor 320, a second drive screw 330, and a pressure application component 340. The bracket 310 is movably mounted on the base 100 in a direction parallel to the surface of the base 100. The second drive motor 320 is fixedly mounted on the bracket 310. The axial direction of the second drive screw 330 is perpendicular to the upper surface of the base 100. One end of the second drive screw 330 is rotatably connected to the bracket 310, and the other end is connected to the drive end of the second drive motor 320. The pressure application component 340 is mounted on the bracket 310 and threadedly fitted to the second drive screw 330. A pressure sensor 500 is connected to the pressure application component 340 and is used to detect the pressure of the pressure application component 340.

[0058] Specifically, the bracket 310 is movably mounted on the base 100 in a direction parallel to the surface of the base 100. It can move horizontally on the base 100 through the cooperation of the first drive motor 410 and the first drive screw 420, with the bottom of the bracket 310 threadedly engaging with the first drive screw 420. The first drive motor 410 drives the first drive screw 420 to rotate, thus achieving horizontal movement of the bracket 310 on the base 100. Alternatively, one side of the bracket 310 can be connected to a hydraulic component, which drives the movement of the bracket 310. The second drive motor 320 is fixedly mounted on the top of the bracket 310 with bolts. The second drive screw 330 is perpendicular to the upper surface of the base 100, with its lower end rotatably connected to the bracket 310 via a bearing, and its upper end connected to the output shaft of the second drive motor 320 via a coupling. The pressure applying component 340 has a threaded hole that forms a threaded engagement with the second drive screw 330, and the pressure sensor 500 is connected to the pressure applying component 340. In specific implementation, when it is necessary to drive the pressure-applying component 340 to contact the side wall of the chip 800, the first drive motor 410 is first started to drive the bracket 310 to move the pressure-applying component 340 horizontally on the base 100 to above the chip 800 placed on the support platform 200. Then, the second drive motor 320 is started to move the pressure-applying component 340 in a direction perpendicular to the base 100 closer to the chip 800. With this configuration, the first drive screw 420 drives the bracket 310 to move horizontally, adjusting the horizontal relative position of the bracket 310 and the pressure-applying component 340 with the chip 800; the second drive screw 330 drives the pressure-applying component 340 to move, adjusting the vertical relative position of the pressure-applying component 340 with the chip 800, achieving precise positioning between the pressure-applying component 340 and the chip 800, so that the pressure-applying component 340 accurately contacts the side wall of the chip 800 and applies force; the pressure sensor 500 detects the pressure value transmitted by the pressure-applying component 340 in real time. Vertical and horizontal movements are separated and designed together to avoid interference from combined movements, ensuring the accuracy of the applied force direction.

[0059] In some embodiments, a hydraulic cylinder is used to drive the vertical movement of the pressure-applying component 340. The hydraulic cylinder is fixed to the top of the bracket 310, and its driving end is connected to the pressure-applying component 340. The pressure-applying component 340 is driven to move in a direction perpendicular to the chip 800 by driving the hydraulic cylinder; or a gear and rack transmission is used, with the rack fixed to the bracket 310 and the gear motor driving the pressure-applying component 340 to move vertically.

[0060] As one possible implementation, such as Figure 1As shown, the pressure-applying component 340 includes a support platform 3401, a cantilever 3402, and a pusher 3403. The support platform 3401 is threadedly connected to the second drive screw 330, and the pressure sensor 500 is fixedly connected to the support platform 3401. The cantilever 3402 includes a first part and a second part fixed to each other. The first part is parallel to the upper surface of the base 100, and the second part is perpendicular to the upper surface of the base 100. The first part is fixedly connected to the pressure sensor 500. The pusher 3403 is fixedly connected to the second part and is used to contact the sidewall of the chip 800 and apply force. Specifically, the support platform 3401 has a threaded through hole in its center, forming a threaded engagement with the second drive screw 330. The pressure sensor 500 is fixed to the side surface of the support platform 3401 by bolts. The cantilever 3402 adopts an L-shaped integrated structure, with its first part extending horizontally and rigidly connected to the pressure sensor 500, and its second part extending vertically downwards. The pusher 3403 is bolted to the end of the second part of the cantilever 3402. In this structure, the support platform 3401 converts the rotation of the second drive screw 330 into displacement perpendicular to the surface of the chip 800. The cantilever 3402 acts as a force transmission intermediary, and the pusher 3403 acts as the force-applying actuator. During operation: when the second drive motor 320 starts, the rotation of the second drive screw 330 drives the support platform 3401 to move vertically, causing the cantilever 3402 and the pusher 3403 to move synchronously. After the pusher 3403 contacts the sidewall of the chip 800, the applied force is rigidly transmitted to the pressure sensor 500 through the cantilever 3402, which outputs pressure data in real time. The 90° angle design between the first horizontal section and the second vertical section of the cantilever 3402 ensures that the pusher 3403 remains parallel to the sidewall of the chip 800 during vertical movement.

[0061] Furthermore, the surface of the pusher 3403 perpendicular to the upper surface of the base 100 is a plane. When the pusher 3403 contacts the chip 800, its planar contact surface is in full contact with the sidewall of the chip 800, avoiding stress concentration caused by point contact. By ensuring that the plane is in parallel contact with the sidewall of the chip 800, the direction of force application is parallel to the surface of the chip 800. This avoids uneven stress distribution caused by point contact at the point of force application, thus preventing stress gradient errors and increasing the accuracy of stress calibration.

[0062] In one possible implementation, the support platform 200 includes a base 210 and a wafer stage 220. The base 210 is fixedly disposed on the base 100, and the wafer stage 220 is fixedly disposed on the base 210. The wafer stage 220 is used to place the chip 800. The limiting structure 230 includes a driving component 2301 and a pushing component 2302. The pushing component 2302 has a portion that moves horizontally on the surface of the wafer stage 220. The third drive motor 23011 is fixedly disposed on the support platform 200. The axial direction of the third drive screw 23012 is parallel to the upper surface of the base 100. One end of the third drive screw 23012 is rotatably connected to the support platform 200, and the other end of the third drive screw 23012 is connected to the driving end of the third drive motor 23011. The limiting structure 230 is threadedly engaged with the third drive screw 23012, and the third drive screw 23012 is used to drive the limiting structure 230 to contact the chip 800.

[0063] The support platform 200 includes a fixed base 210, a wafer carrier 220 for placing the chip 800 mounted thereon, and a limiting structure 230 slidably mounted on the wafer carrier 220. A third drive motor 23011 is fixed to one end of the support platform 200, and a third drive screw 23012 is horizontally positioned and axially parallel to the surface of the wafer carrier 220. One end of the screw is rotatably connected to the support platform 200 via a bearing seat, and the other end is connected to the output shaft of the third drive motor 23011 via a coupling. The bottom of the limiting structure 230 has a threaded interface that forms a threaded engagement with the third drive screw 23012. In this structure, the wafer carrier 220 serves as a static reference surface, and the limiting structure 230 achieves horizontal displacement through the transmission of the third drive screw 23012. In specific implementation: After the chip 800 is placed on the stage 220, the third drive motor 23011 starts and drives the third drive screw 23012 to rotate. The limiting structure 230 moves horizontally along the screw axis of the third drive screw 23012 through threaded engagement, pushing the stop block 23022 to fit tightly against the side wall of the chip 800 to achieve positioning; and limiting the chip 800 to a specific position. When the pressure application component 300 applies pressure to the side wall of the chip 800, the chip 800 will not move, ensuring accurate stress calculation.

[0064] Furthermore, such as Figure 2 As shown, the limiting structure 230 includes a push block 23021 and a stop block 23022; wherein, the push block 23021 is threadedly connected to the third drive screw 23012; the stop block 23022 is slidably disposed on the plate stage 220, and the stop block 23022 is connected to one end of the push block 23021.

[0065] The pusher block 23021 has a threaded through hole at its bottom, forming a threaded connection with the third drive screw 23012. The stop block 23022 is mounted on the wafer stage 220 and is connected to the front end of the pusher block 23021. In this structure, the third drive screw 23012 is horizontally mounted on the support platform 200, and the pusher block 23021 converts the rotational motion of the third drive screw 23012 into linear displacement. The stop block 23022 directly contacts the sidewall of the chip 800. During operation: after the third drive motor 23011 starts, it drives the third drive screw 23012 to rotate. The pusher block 23021 moves horizontally along the axial direction of the third drive screw 23012, pushing the stop block 23022 to slide along the wafer stage 220 until it is in close contact with the sidewall of the chip 800 to complete the positioning and limit the chip 800 to a specific position. This configuration improves the positioning stability of the chip 800 and prevents scratches on the chip 800 surface by having the stop block 23022 make face-to-face contact with the sidewall of the chip 800; and the face-to-face contact between the stop block 23022 and the sidewall of the chip 800 ensures the uniformity of stress on the surface of the chip 800.

[0066] Furthermore, the support platform 200 is also equipped with a slide rail, the extension direction of which is parallel to the upper surface of the support platform 200. The push block 23021 is connected to the slide rail guide. Specifically, the slide rail is fixedly installed on the surface of the support platform 200 by bolts, and its extension direction is parallel to the upper surface of the support platform 200. The bottom of the push block 23021 is provided with a slider structure, which forms a sliding fit with the guide groove of the slide rail. In this structure, the slide rail is fixed to the surface of the support platform 200 as a rigid reference, and the push block 23021 is embedded in the guide groove of the slide rail through the slider to achieve horizontal movement constraint. During operation: when the third drive screw 23012 rotates, the push block 23021 moves horizontally along the axial direction of the third drive screw 23012, and the slider slides along the guide groove of the slide rail. The circumferential torque generated by the rotation of the third drive screw 23012 is resisted by the contact between the groove wall and the side of the slider, ensuring that the push block 23021 only moves in a single direction and avoiding the deflection or pitch of the stop block 23022. With this configuration, the slide rail guide eliminates radial offset during the movement of the push block 23021, ensuring that the stop block 23022 is always perpendicularly attached to the side wall of the chip 800.

[0067] As one possible implementation, both the limiting surface of the limiting structure 230 and the pressure surface of the pressure application component 300 are provided with adhesives, which are used to bond and fix to the sidewall of the chip 800.

[0068] Specifically, the adhesive can be an adhesive layer, which is fixed to the contact surface of the limiting structure 230 facing the chip 800 and the contact surface of the pressure application component 300 facing the chip 800. In this structure, the adhesive layer covers the contact surfaces, wherein the adhesive layer of the limiting structure 230 is used to bond and fix to one side wall of the chip 800, and the adhesive layer of the pressure application component 300 is used to bond and fix to the other side wall of the chip 800. During operation: In tensile stress calibration mode, chip 800 is first placed on support platform 200. Limiting structure 230 is bonded to chip 800 via adhesive layer on its surface. Pressure application component 300 moves to the other side of chip 800 and is bonded to the other side wall of chip 800 via adhesive layer on its surface. Subsequently, pressure application component 300 moves away from chip 800, applying a tensile force away from chip 800. At this time, both sides of chip 800 are rigidly connected to limiting structure 230 and pressure application component 300 via adhesive components, achieving uniform tensile stress loading. The adhesive component allows the chip 800 stress calibration device to be compatible with both pushing and stretching modes, overcoming the limitation of traditional bending methods that can only achieve unidirectional stress. The adhesive contact surface is fully bonded to the chip 800, avoiding stress concentration caused by point contact. Furthermore, the replaceable adhesive component adapts to the surface characteristics of chips 800 made of different materials. In some embodiments, the adhesive includes an electromagnetic adsorption adhesive that generates magnetic attraction to fix the metal chip 800 after being energized; or a vacuum suction cup adhesive is provided on the limiting structure 230 and the pressure application component 300 to fix the sidewall of the chip 800 by negative pressure adsorption.

[0069] As one possible implementation, the electrical signal measuring element includes two probes 600, and the chip 800 stress calibration device also includes a controller, which is communicatively connected to the pressure sensor 500 and the two probes 600, respectively. The two probes 600 are used to contact the two pads of the stress sensing element on the surface of the chip 800.

[0070] Specifically, two probes 600 are mounted on the side of the base 100, with their tips corresponding to the two pads of the stress sensing element on the surface of the chip 800. The controller is communicatively connected to the signal output terminals of the pressure sensor 500 and the probes 600 via wires. The probes 600 are used to acquire electrical signals, and the controller is used for data processing. During operation: when the pressure application component 300 applies force to the chip 800, the two probes 600 simultaneously contact the pads on the surface of the chip 800, acquiring the resistance or voltage change signal of the stress sensing element in real time; the controller simultaneously receives the pressure data transmitted by the pressure sensor 500 and the electrical signal transmitted by the probes 600, dynamically correlating the stress value with the electrical signal response. This configuration achieves direct acquisition of electrical signals through direct contact between the dual probes 600 and the pads, eliminating transmission losses introduced by indirect measurement; the controller synchronously processes stress and electrical signal data, establishing real-time calibration data and avoiding errors caused by step-by-step measurements.

[0071] Secondly, embodiments of the present invention also provide a chip stress calibration method, wherein the method uses any of the chip stress calibration devices described in the above embodiments to perform stress calibration, and includes the following steps:

[0072] Step S100: Place the chip on the carrier stage, with one side wall of the chip in contact with the limiting surface of the limiting structure of the carrier stage;

[0073] In step S200, the pressure application component is driven to move to the other side of the chip by the driving component, so that the pressure application surface of the pressure application component contacts the other side wall of the chip.

[0074] Step S300: Apply force to the chip through the pressure application component;

[0075] Step S400: The pressure data of the chip and the electrical signal of the electrical signal measuring element are synchronously acquired through the pressure sensor and the electrical signal measuring element.

[0076] Step S500: Associate the pressure data and electrical signals to complete the stress calibration of the chip.

[0077] In practice, the chip under test 800 is placed freely on the wafer stage 220 of the support platform 200. The third drive motor 23011 is started to drive the third drive screw 23012 to rotate, pushing the stop block 23022 of the limiting structure 230 to move horizontally along the wafer stage 220 until the stop block 23022 is in close contact with one side wall of the chip 800 to complete the positioning. If it is in stretching mode, an adhesive is added to the contact surface between the stop 23022 and the chip 800 to achieve fixed bonding; the first drive motor 410 is started to drive the first drive screw 420 to rotate, which drives the bracket 310 of the pressure application component 300 to move horizontally along the first slide rail 700 of the base 100 to the other side of the chip 800. Then the second drive motor 320 is started to drive the second drive screw 330 to rotate, so that the pressure application component 340 descends vertically. The height of the pusher 3403 is adjusted by the cantilever 3402 until its planar contact surface is parallel and aligned with the side wall of the chip 800. If it is for tensile stress calibration, adhesive is simultaneously applied to the contact surface of the pusher 3403. The component is bonded and fixed to the sidewall of chip 800 to form a bidirectional rigid connection. The two probes 600 of the electrical signal measuring element are respectively contacted with the two pads of the stress sensing element on the surface of chip 800. The position of the probes 600 is finely adjusted to ensure stable contact. Then, the driving component is adjusted to drive the pressure application component to apply different magnitudes of force to the sidewall of the chip 800 under test, and the data of the pressure sensor and the electrical signal of the electrical signal measuring element are collected simultaneously to realize the direct acquisition of electrical signals. The data is transmitted to the controller, which processes the stress and electrical signal data simultaneously, establishes real-time calibration data, generates a stress calibration curve, and completes the stress calibration of the chip under test.

[0078] Compared with the prior art, the beneficial effects of the chip stress calibration method provided in the embodiments of the present invention are the same as those of the chip stress calibration device provided in the above embodiments, and will not be repeated here.

[0079] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0080] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A chip stress calibration device, characterized in that, include: Base; A support platform is fixedly mounted on the base. The support platform is used to support the chip. A limiting structure is provided on the support platform. The limiting structure has a limiting surface for limiting the chip. A pressure-applying component is movably disposed on the base. The pressure-applying component is located at one end of the base away from the limiting structure. The pressure-applying component has a pressure-applying surface for contacting the sidewall of the chip and applying a force to the chip close to the limiting structure. A driving component, disposed on the base, is used to drive the pressure application component to move in a direction parallel to the upper surface of the base; A pressure sensor, connected to the pressure application component, is used to detect the pressure applied to the chip by the pressure application component; An electrical signal measuring element is provided, which is electrically connected to the chip to monitor changes in the electrical signal of the chip.

2. The chip stress calibration device according to claim 1, characterized in that, The driving component includes: A first drive motor is fixedly mounted on the base; A first drive screw, the axis of which is parallel to the upper surface of the base, one end of which is rotatably connected to the base, and the other end of which is connected to the drive end of the first drive motor. The pressure application component is disposed on the base and threadedly engaged with the first drive screw.

3. The chip stress calibration device according to claim 1, characterized in that, The base is also provided with a first slide rail, the extension direction of the first slide rail is parallel to the upper surface of the base, and the pressure application component is guided and connected to the first slide rail.

4. The chip stress calibration device according to claim 1, characterized in that, The pressure application component includes: A bracket, which is movably disposed on the base in a direction parallel to the surface of the base; The second drive motor is fixedly mounted on the bracket. The second drive screw has its axis perpendicular to the upper surface of the base. One end of the second drive screw is rotatably connected to the bracket, and the other end of the second drive screw is connected to the drive end of the second drive motor. A pressure-applying component is disposed on the bracket and threadedly connected to the second drive screw. The pressure sensor is connected to the pressure-applying component and is used to detect the force applied by the pressure-applying component.

5. The chip stress calibration device according to claim 4, characterized in that, The pressure-applying component includes: A support platform is provided on the bracket and threaded to the second drive screw, and the pressure sensor is fixedly connected to the support platform; The cantilever includes a first part and a second part fixed to each other. The first part is parallel to the upper surface of the base, and the second part is perpendicular to the upper surface of the base. The first part is fixedly connected to the pressure sensor. A pusher blade is fixedly connected to the second part and is used to contact the sidewall of the chip and apply force.

6. The chip stress calibration device according to claim 1, characterized in that, The support platform includes: The substrate is fixedly disposed on the base; A wafer carrier stage is fixedly disposed on the substrate and is used to place a chip. The limiting structure includes a driving component and a pushing component, and the pushing component has a portion that moves horizontally on the surface of the wafer carrier stage.

7. The chip stress calibration device according to claim 6, characterized in that, The driving component includes a third driving motor and a third driving screw. The third driving motor is fixedly mounted on the support platform. The axial direction of the third driving screw is parallel to the upper surface of the base. One end of the third driving screw is rotatably connected to the support platform, and the other end of the third driving screw is connected to the driving end of the third driving motor. The pushing component is threadedly engaged with the third driving screw. The third driving screw is used to drive the pushing component to contact the chip. The pushing component includes a push block and a stop block. The push block is threadedly connected to the third drive screw, and the stop block is slidably disposed on the wafer stage. The stop block is connected to one end of the push block and is used to limit contact with the end of the chip.

8. The chip stress calibration device according to claim 1, characterized in that, Both the limiting surface of the limiting structure and the pressure surface of the pressure application component are provided with adhesive members, which are used to bond and fix to the sidewall of the chip.

9. The chip stress calibration device according to claim 1, characterized in that, The electrical signal measuring element includes two probes, and the chip stress calibration device further includes a controller. The controller is communicatively connected to the pressure sensor and the two probes, respectively. The two probes are used to contact the two pads of the chip surface stress sensing element.

10. A method for calibrating chip stress, characterized in that, Stress calibration using the chip stress calibration apparatus according to any one of claims 1-9 includes the following steps: The chip is placed on the support platform, and one side wall of the chip contacts the limiting surface of the limiting structure of the support platform; The driving component drives the pressure application component to move to the other side of the chip, so that the pressure application surface of the pressure application component contacts the other side wall of the chip; A force is applied to the chip through the pressure-applying component; The pressure data and electrical signals of the chip are acquired synchronously by the pressure sensor and the electrical signal measuring element. The stress calibration of the chip is completed by associating the pressure data with the electrical signals.

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