Wafer multi-level test device and test method

Abstract

The invention relates to the technical field of wafer testing, in particular to a wafer multi-level testing device and method, the wafer multi-level testing device comprises a rack, a wafer bearing table, a testing head and a probe card, the probe card comprises a testing circuit board, an adjusting substrate and a testing probe, the wafer bearing table and the testing head are both arranged on the rack, and the testing circuit board is installed on the testing head. According to the invention, the adjusting substrate is arranged and is movably connected with the test head, so that the adjusting substrate can freely stretch out and draw back to release stress when being heated, the deformation quantity of the adjusting substrate can be reduced, and the adjusting substrate is extruded to change the warping shape of the adjusting substrate into a straight shape, so that the position of the test probe is adjusted; the influence caused by the horizontal position offset of the end part of the test probe is avoided, and the test probe has elasticity and can adapt to the displacement deviation in the vertical direction, so that the problems of probe alignment failure, poor contact or test signal distortion of the test device caused by the position offset of the test probe due to high-temperature warping of the circuit board are avoided.

Description

Technical Field

[0001] This invention relates to the field of wafer testing technology, specifically to a wafer multi-level testing device and testing method. Background Technology

[0002] With the rapid development of semiconductor manufacturing technology, the requirements for evaluating the reliability of integrated circuit interconnects are becoming increasingly stringent. Electromigration (EM) testing, as a key evaluation method, is usually conducted in high-temperature environments above 300°C to accelerate the failure process and predict the lifespan of metal wires. However, during such high-temperature testing, the testing equipment itself, especially the probe card, is susceptible to thermal deformation, leading to decreased testing accuracy and efficiency, which has become a major bottleneck restricting testing reliability and efficiency.

[0003] In existing technologies, to shorten the temperature pretreatment time before testing, a solution is to add a heat insulation layer to the lower surface of the circuit board of the probe card to reduce temperature fluctuations and accelerate the preheating process. For example, the utility model patent with application number CN202320427782.1 uses this method, which alleviates the temporary probe position shift caused by excessively rapid temperature changes to a certain extent. However, under continuous high-temperature steady-state conditions, the circuit board material itself will still undergo significant thermal expansion and warping deformation, resulting in three-dimensional spatial position deviations of the densely arranged micron-level test probes. This probe position shift caused by material thermal deformation persists even after the system reaches thermal equilibrium, easily leading to misalignment, abnormal contact resistance, or electrical signal distortion, seriously affecting the accuracy and repeatability of electrical performance testing.

[0004] To avoid probe position displacement caused by high-temperature warping of circuit boards, a wafer multi-level testing device and testing method are proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a wafer multi-level testing device and testing method. By allowing the adjustment substrate to freely expand and contract to release stress when heated, the deformation of the adjustment substrate is reduced. Then, by pressing the adjustment substrate with a lateral limiting plate and a longitudinal extrusion, the adjustment substrate can be changed from a warped shape to a straight shape, thereby adjusting the position of the test probe and avoiding the horizontal position deviation of the test probe tip, which would have an impact. The test probe is elastic and can adapt to vertical displacement deviation, thereby avoiding the test probe position deviation caused by high temperature warping of the circuit board, which would cause problems such as test device probe alignment failure, poor contact, or test signal distortion.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A multi-level wafer testing apparatus includes a rack, a wafer carrier stage, a test head, and a probe card. The probe card includes a test circuit board, an adjustment substrate, and test probes. The wafer carrier stage and the test head are both mounted on the rack. The wafer carrier stage is configured to support, translate, rotate, and heat the wafer. The test head is equipped with a test circuit board, and the test probes are connected to the test circuit board and are elastic. An adjustment substrate is movably connected to the test head, and the test probes penetrate the adjustment substrate. The test head is provided with a lateral limiting mechanism and a longitudinal limiting mechanism, and lateral limiting plates and longitudinal limiting plates are respectively connected to the lateral limiting mechanism and the longitudinal limiting mechanism. Both the lateral limiting plates and the longitudinal limiting plates are in contact with the adjustment substrate. The test head is provided with a positioning element for positioning the adjustment substrate.

[0007] By setting an adjustment substrate, which is movably connected to the test head, the adjustment substrate can freely expand and contract to release stress when heated, thus reducing the deformation of the adjustment substrate. Furthermore, by pressing the adjustment substrate with a lateral limiting plate and longitudinal compression, even if the adjustment substrate undergoes warping deformation, it can be straightened from a warped shape. This adjusts the position of the test probe and avoids the horizontal position deviation of the test probe tip, which would have an impact. The test probe is elastic and can adapt to vertical displacement deviation, thereby avoiding the test probe position deviation caused by high temperature warping of the circuit board, which could lead to test device probe alignment failure, poor contact, or test signal distortion.

[0008] Preferably, the positioning element includes two positioning slots symmetrically arranged on the test head, and two positioning rods symmetrically arranged on the adjustment base plate. The two positioning rods are slidably installed inside the two positioning slots respectively. One of the positioning slots has a positioning surface inside, and the positioning rod inside the positioning slot is in contact with the positioning surface. The positioning surface is perpendicular to the common plane of the two positioning slots.

[0009] The positioning component, with its two positioning rods, prevents the adjustment base plate from moving in the lateral direction. When the positioning rods are in contact with the positioning surface, they can be positioned in the longitudinal direction, thereby preventing the test probe from moving too far in the horizontal direction, which could lead to stress fatigue damage to the test probe.

[0010] Preferably, a spring is provided inside the positioning groove, with both ends of the spring contacting the positioning rod and the inner wall of the positioning groove, respectively, and the spring force direction is towards the positioning surface.

[0011] The spring inside the positioning groove can keep the adjusting plate stable by squeezing the positioning rod, avoiding vibration caused by the adjusting plate moving up and down the horizontal and vertical limiting plates, which would easily lead to stress fatigue and damage to the test probe. The spring can also squeeze the positioning rod to move towards the positioning surface, ensuring that the positioning rod fits the positioning surface. This prevents the adjusting plate from moving due to warping when the horizontal limiting plate moves down, which would cause the adjusting plate to deviate and result in excessive deformation of the test probe, thus damaging the test probe.

[0012] Preferably, the positioning surface has a first inclined surface, and the positioning rod has a second inclined surface that fits with the first inclined surface, the height of the first inclined surface being greater than the height of the second inclined surface.

[0013] The setting of inclined plane one and inclined plane two, with the height of inclined plane one being greater than the height of inclined plane two, allows the adjusting base plate to be raised to a certain height under the action of spring force. This prevents the horizontal limiting plate from generating a horizontal component force on the adjusting base plate when it squeezes the adjusting base plate, thus avoiding the problem of the positioning rod not being able to fit with the positioning surface.

[0014] Preferably, the lateral limiting plate and the longitudinal limiting plate are made of elastic material. The lateral limiting plate bends upward from the middle to both sides. The test head is provided with at least three lateral limiting mechanisms, and the number of each mechanism is a basic number. Multiple lateral limiting mechanisms are equidistantly connected to the lateral limiting plate. The lateral limiting mechanism located in the middle is fixedly connected to the middle of the lateral limiting plate. The test head is provided with at least two longitudinal limiting mechanisms. The longitudinal limiting plate bends upward from one end of the positioning surface to the other end. The longitudinal limiting plate is fixedly connected to the longitudinal limiting mechanism at one end of the positioning surface. The longitudinal limiting mechanism located on the side of the positioning surface away from the longitudinal limiting plate and the lateral limiting mechanisms located on both sides are provided with sliding rods. The longitudinal limiting mechanism located on the side of the positioning surface away from the longitudinal limiting plate is slidably connected to the longitudinal limiting plate through the sliding rods, and the lateral limiting mechanisms located on both sides are slidably connected to the lateral limiting plate through the sliding rods.

[0015] The adjustment substrate is usually warped along the middle. Therefore, the lateral limiting plate is designed to bend upwards from the middle to both sides, so that the lateral limiting plate can flatten the adjustment substrate from the middle to both sides. The longitudinal limiting plate bends upwards from one end of the positioning surface to the other end, so that the lateral limiting plate can flatten the adjustment substrate along one side of the positioning surface. This ensures the flatness of the adjustment substrate, avoids the test probe position deviation, and ensures that the adjustment substrate will not deform to the side of the positioning surface. This avoids the positioning surface restricting the deformation of the adjustment substrate, which would prevent the adjustment substrate from being flattened.

[0016] Preferably, the test head is provided with a step, the height of which is 2-5 μm greater than the height of the adjustment base plate, and both the lateral limiting plate and the longitudinal limiting plate are in contact with the step.

[0017] The step design allows the lateral and longitudinal limiting plates to be pressed together on the step, enabling expansion and contraction even when the test temperature changes, thus preventing irregular deformation of the adjustment substrate. The step height is 2-5µm greater than the adjustment substrate height, ensuring that the deformation of the adjustment substrate is within the normal range and will not cause excessive displacement of the test probe position. Furthermore, the step design prevents direct pressure on the adjustment substrate, so the deformation of the adjustment substrate under pressure will not encounter significant resistance, thereby avoiding excessive friction that would prevent the adjustment substrate from being flattened.

[0018] Preferably, multiple heat-conducting grooves are formed on the contact surface between the test head and the adjustment substrate.

[0019] The heat-conducting grooves can relieve stress on the test head, prevent the test head from expanding and arching due to thermal expansion, and ensure the positioning accuracy of the test head. The heat-conducting grooves can also improve the uniformity of the temperature of the regulating substrate and prevent irregular deformation caused by uneven heating of the regulating substrate.

[0020] Preferably, the test probe includes a connecting part, an elastic part, and a detection part. The connecting part is connected to the test circuit board, and the detection part is connected to the connecting part through the elastic part. The elastic part is bent, and the bending direction is toward the radial direction of the test circuit board.

[0021] The flexible bending design allows the test probes to bend to one side when compressed, thus avoiding stress fatigue damage caused by bending to the opposite side. The bending direction is towards the radial direction of the test circuit board, which can prevent the elastic part from generating torque when adjusting the thermal expansion and contraction of the substrate, thus avoiding stress fatigue damage.

[0022] A testing method applied to the aforementioned wafer multi-level testing apparatus includes the following steps: S1. First, place the wafer on the wafer carrier stage and preheat the wafer and probe card; S2. After preheating, start the lateral limiting mechanism to push the lateral limiting plate down to squeeze the adjusting plate, and stop when the internal pressure of the lateral limiting mechanism reaches the set value. S3. After the lateral limiting mechanism stops extending, the longitudinal limiting mechanism is activated to push the longitudinal limiting plate down to squeeze the adjusting plate, and stops when the internal pressure of the longitudinal limiting mechanism reaches the set value. S4. After the longitudinal limiting mechanism stops extending, control the wafer carrier stage to adjust the wafer position and control the test head to move down so that the test probe contacts the wafer. S5. After the test probe contacts the wafer, the wafer electromigration test begins.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By setting an adjustment base plate, and movably connecting the adjustment base plate to the test head, the adjustment base plate can freely expand and contract to release stress when heated, thus reducing the deformation of the adjustment base plate. By pressing the adjustment base plate with the lateral limiting plate and the longitudinal extrusion, the adjustment base plate can be changed from a warped shape to a straight shape, thereby adjusting the position of the test probe and avoiding the horizontal position deviation of the test probe tip, which would have an impact. The test probe is elastic and can adapt to the vertical displacement deviation, thereby avoiding the test probe position deviation caused by the high temperature warping of the circuit board, which would cause the test device to fail to align the probe, poor contact, or test signal distortion.

[0024] 2. The positioning components prevent the test probe from moving too far horizontally, which could lead to stress fatigue damage. The spring in the positioning groove keeps the adjusting plate stable by squeezing the positioning rod, preventing vibration caused by the adjusting plate moving up and down the horizontal and vertical limiting plates. This would prevent the test probe from being easily damaged by stress fatigue. The spring can also squeeze the positioning rod to move towards the positioning surface, ensuring that the positioning rod fits the positioning surface. This prevents the adjusting plate from warping and moving when the horizontal limiting plate moves down, which could cause the adjusting plate to deviate and result in excessive deformation of the test probe, thus damaging the test probe.

[0025] 3. By setting inclined plane one and inclined plane two on the positioning surface and positioning rod respectively, and the height of inclined plane one is greater than the height of inclined plane two, the adjustment base plate can be raised to a certain height under the action of spring force. This prevents the horizontal limiting plate from generating a horizontal component force on the adjustment base plate when it squeezes the adjustment base plate, thus avoiding the problem that the positioning rod cannot fit with the positioning surface, resulting in excessive deformation of the test probe and damage to the test probe. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the present invention; Figure 3 for Figure 2 Enlarged view of a portion of point A in the middle; Figure 4 for Figure 1 Sectional view at point BB; Figure 5 for Figure 4 Enlarged view of a section at point C; Figure 6 This is a cross-sectional view of the panel and mounting plate of the present invention when separated; Figure 7 for Figure 6 Enlarged view of a section at point D; Figure 8 This is a cross-sectional view of the contact block portion of the present invention.

[0027] In the diagram: 1. Rack; 2. Wafer carrier stage; 3. Test head; 4. Probe card; 41. Test circuit board; 42. Adjustment substrate; 43. Test probe; 431. Connecting part; 432. Elastic part; 433. Detection part; 5. Lateral limiting mechanism; 6. Longitudinal limiting mechanism; 7. Lateral limiting plate; 8. Longitudinal limiting plate; 9. Positioning component; 91. Positioning groove; 92. Positioning rod; 93. Positioning surface; 10. Spring; 11. Inclined surface one; 12. Inclined surface two; 13. Sliding rod; 14. Step; 15. Heat conduction groove; 16. Servo system. Detailed Implementation

[0028] Please see Figures 1 to 8 This invention provides a wafer multi-level testing device and testing method, the technical solution of which is as follows: A multi-level wafer testing apparatus includes a rack 1, on which a wafer carrier stage 2 is mounted. The wafer carrier stage 2 is configured to support, translate, rotate, and heat wafers. A servo system 16 is mounted on the rack 1, including a servo motor and a lead screw. A test head 3 is connected to the lead screw, and a probe holder 4 is mounted on the test head 3. The probe holder 4 includes a test circuit board 41, an adjustment substrate 42, and test probes 43. The test circuit board 41 is bolted to the test head, and the test probes 43 are connected to the test circuit board 41. The test probes 43 include a connecting portion 431, an elastic portion 432, and a detection portion 433. The elastic portion 432 is elastic. The connecting part 431 is connected to the test circuit board 41, and the detection part 433 is connected to the connecting part 431 through the elastic part 432. An adjustment base plate 42 is movably mounted on the test head 3, and the connecting part 431 passes through the adjustment base plate 42. The test head 3 is provided with a lateral limiting mechanism 5 and a longitudinal limiting mechanism 6. A lateral limiting plate 7 and a longitudinal limiting plate 8 are respectively connected to the lateral limiting mechanism 5 and the longitudinal limiting mechanism 6 (the lateral direction and the longitudinal direction are represented by the X and Y directions in the attached figure, respectively). The lateral limiting plate 7 and the longitudinal limiting plate 8 are both in contact with the adjustment base plate 42. The test head 3 is provided with a positioning part 9. In order to reduce the vibration of the test head 3, the lateral limiting mechanism 5 and the longitudinal limiting mechanism 6 are connected to the adjustment base plate 42. All limiting mechanisms 6 are hydraulic cylinders. During preheating of the probe card 4 and the wafer, the lateral limiting mechanism 5 and the longitudinal limiting mechanism 6 are not extended. At this time, the lateral limiting plate 7 and the longitudinal limiting plate 8 will not press against the adjusting substrate 42. During preheating, because the adjusting substrate 42 is movably mounted on the test head 3, it can freely expand and contract to release stress when the temperature changes, thus reducing the deformation of the adjusting substrate 42. After preheating, the lateral limiting mechanism 5 extends, pushing the lateral limiting plate 7 to press against the adjusting substrate 42, preventing the adjusting substrate 42 from arching laterally. When the lateral limiting mechanism 5 stops, the longitudinal limiting mechanism 6 extends, allowing the adjusting substrate 42 to no longer arch laterally. When the longitudinal direction of the adjustment substrate 42 is no longer arched, the adjustment substrate 42 can be straightened from its warped shape when it warps, thereby adjusting the position of the test probe 43 and avoiding the horizontal position displacement of the end of the test probe 43. The elastic part 432 is elastic and can adapt to the vertical displacement deviation, thereby avoiding the test probe 43 position displacement caused by the high temperature warping of the circuit board, which would cause the test device to fail to align the probe, poor contact or test signal distortion. The positioning part 9 can position the adjustment substrate and avoid the problem of excessive displacement of the adjustment substrate 42, which would cause excessive deformation of the test probe 43 and damage.The positioning component 9 includes two positioning grooves 91 symmetrically arranged on the test head 3, and two positioning rods 92 symmetrically arranged on the adjustment base plate 42. The two positioning rods 92 are located on the longitudinal symmetry plane of the adjustment base plate 42. The two positioning rods 92 are slidably installed inside the two positioning grooves 91 respectively. One of the positioning grooves 91 has a positioning surface 93 inside. The positioning rod 92 located inside the positioning groove 91 is in contact with the positioning surface 93. The positioning surface 93 is perpendicular to the common plane of the two positioning grooves 91. Since the two positioning rods 92 are located on the longitudinal symmetry plane of the adjustment base plate 42 and are located in the positioning grooves 91 respectively, the lateral deformation of the adjustment base plate 42 is from the middle to the two sides. Lateral deformation is achieved to position the adjustment substrate 42 in the lateral direction, while the positioning rod 92 fits against the positioning surface 93 to position the adjustment substrate 42 in the longitudinal direction. This allows the position of the test probe 43 to be adjusted according to the extension and retraction of the adjustment substrate 42, thereby preventing the adjustment substrate 42 from moving freely and causing the test probe 43 to move too far in the horizontal direction, resulting in stress fatigue or excessive deformation and damage to the test probe 43. A spring 10 is provided inside the positioning groove 91, with both ends of the spring 10 contacting the positioning rod 92 and the inner wall of the positioning groove 91, respectively. The spring force direction of the spring 10 is towards the positioning surface 93, which can always push the adjustment substrate 42. The plate 42 is attached to the positioning surface 93 to prevent the adjustment plate 42 from warping and moving when the lateral limiting plate 7 moves downward, which could cause the adjustment plate 42 to deviate and result in excessive deformation of the test probe 43, leading to damage. The spring 10 constantly presses the positioning rod 92 to keep the adjustment plate 42 stable, preventing vibration caused by the upward movement of the adjustment plate 42 on the lateral limiting plate 7 and the longitudinal limiting plate 8, which could easily lead to stress fatigue and damage to the test probe 43. The positioning surface 93 has a first inclined surface 11, and the positioning rod 92 has a second inclined surface 12 that fits against the first inclined surface 11. The height of the first inclined surface 11 is greater than the height of the second inclined surface 12. When the spring 10 pushes the positioning rod 92... When inclined plane 11 is attached to inclined plane 12, since the height of inclined plane 11 is greater than the height of inclined plane 12, the positioning rod 92 moves obliquely upward along inclined plane 11. This ensures that when the transverse limiting plate 7 presses against the adjusting base plate 42, the positioning rod 92 remains attached to inclined plane 11 and stops moving when the adjusting base plate 42 is attached to the test head 3. This avoids the transverse limiting plate 7 exerting a horizontal force on the adjusting base plate 42, preventing the positioning rod 92 from failing to attach to the positioning surface 93. Furthermore, the lifting of the adjusting base plate 42 creates a gap between its lower side and the test head 3, resulting in more uniform temperature during preheating and cooling of the adjusting base plate 42 and preventing irregular deformation due to uneven heating.

[0029] The transverse limiting plate 7 and the longitudinal limiting plate 8 are made of nickel-based high-temperature alloy. Nickel-based high-temperature alloy has good elasticity and can withstand a maximum temperature of 800℃. The transverse limiting plate 7 bends upward from the middle to both sides. The test head 3 is equipped with three transverse limiting mechanisms 5, which are equidistantly connected to the transverse limiting plate 7. The transverse limiting mechanism 5 located in the middle is fixedly connected to the middle of the transverse limiting plate 7. The test head 3 is equipped with two longitudinal limiting mechanisms 6. The longitudinal limiting plate 8 bends upward from one end of the positioning surface 93 to the other end. The longitudinal limiting plate 8 located on the positioning surface 93 is fixedly connected to the longitudinal limiting mechanism 6. The longitudinal limiting mechanism 6 located on the side away from the longitudinal limiting plate 8 on the positioning surface 93, as well as the transverse limiting mechanisms 5 located on both sides, are equipped with... A sliding rod 13 is provided. The longitudinal limiting mechanism 6, located on the side of the positioning surface 93 away from the longitudinal limiting plate 8, is slidably connected to the longitudinal limiting plate 8 via the sliding rod 13. The transverse limiting mechanisms 5 located on both sides are slidably connected to the transverse limiting plate 7 via the sliding rod 13. The transverse limiting plate 7 is designed to bend upwards from the center to both sides, so that the transverse limiting plate 7 can flatten the adjusting substrate 42 from the center to both sides. The longitudinal limiting plate 8 bends upwards from one end of the positioning surface 93 to the other end, so that the transverse limiting plate 7 can flatten the adjusting substrate 42 along one side of the positioning surface 93. This ensures the flatness of the adjusting substrate 42, prevents the test probe 43 from shifting position, and ensures that the adjusting substrate 42 does not deform towards the positioning surface 93, thus preventing the positioning surface 93 from restricting the adjusting substrate 42. Deformation prevents the adjustment substrate 42 from being flattened. The test head 3 has a step 14, the height of which is 5µm greater than the height of the adjustment substrate 42. The lateral limiting plate 7 and the longitudinal limiting plate 8 are attached to the step 14. The lateral limiting plate 7 and the longitudinal limiting plate 8 are pressed onto the step 14, and the warpage height of the adjustment substrate 42 is 5µm, ensuring that the deformation of the adjustment substrate 42 is within the normal range and will not cause excessive displacement of the test probe 43. Furthermore, the step 14 prevents direct pressure on the adjustment substrate 42. Therefore, even when the adjustment substrate 42 is deformed by pressure, it still has gaps for movement and will not experience significant resistance, thus avoiding excessive friction that would prevent the adjustment substrate 42 from being flattened. The elastic part 432 is bent. Furthermore, the bending direction is towards the radial direction of the test circuit board 41; the bending setting of the elastic part 432 allows the test probe 43 to bend to one side when squeezed, thereby avoiding stress fatigue damage caused by bending to the opposite side. The bending direction is towards the radial direction of the test circuit board 41, which can prevent the elastic part 432 from generating torque when the adjustment substrate 42 expands and contracts with heat, thus avoiding stress fatigue damage. Multiple heat-conducting grooves 15 are formed on the contact surface between the test head 3 and the adjustment substrate 42. The setting of the heat-conducting grooves 15 can release the stress of the test head 3, prevent the test head 3 from arching due to thermal expansion, and ensure the positioning accuracy of the test head 3. The setting of the heat-conducting grooves 15 can also improve the temperature uniformity of the adjustment substrate 42, and prevent the adjustment substrate 42 from being irregularly deformed due to uneven heating.

[0030] A testing method applied to the aforementioned wafer multi-level testing apparatus includes the following steps: S1. First, place the wafer on the wafer carrier stage 2 and preheat the wafer and probe card 4. At this time, the lateral limiting mechanism 5 and the longitudinal limiting mechanism 6 are not extended. The positioning rod 92 is squeezed by the adjusting substrate 42 and rises 3um along the inclined plane 11. S2. After preheating, multiple lateral limiting mechanisms 5 are activated to push the lateral limiting plates 7 down to press the adjusting base plate 42. The middle part of the lateral limiting plate 7 first contacts the adjusting base plate 42, and then the two lateral limiting plates 7 on both sides contact the adjusting base plate 42. During this process, the lateral limiting plates change from a curved shape to a straight shape, pressing the adjusting base plate 42 flat from the middle to both sides. When the lateral adjusting base plate 42 contacts the step 14, the lateral limiting mechanism 5 stops extending by pressure control. S3. After the lateral limiting mechanism 5 stops extending, multiple longitudinal limiting mechanisms 6 are activated to push the longitudinal limiting plate 8 down to press the adjusting base plate 42. The end of the longitudinal limiting plate 8 located on the positioning surface 93 side first contacts the adjusting base plate 42, and then the other end of the longitudinal limiting plate 8 contacts the adjusting base plate 42. During this process, the longitudinal limiting plate changes from a curved shape to a straight shape, pressing the adjusting base plate 42 flat along the lateral limiting plate 7 along the positioning surface 93 side. When the longitudinal adjusting base plate 42 contacts the step 14, the longitudinal limiting mechanism 6 stops extending by pressure control. S4. After the longitudinal limiting mechanism 6 stops extending, control the wafer carrier stage 2 to adjust the wafer position and control the test head 3 to move down so that the test probe 43 contacts the wafer. S5. After the test probe 43 contacts the wafer, the wafer electromigration test begins. Once completed, the test head 3 is moved upwards, and the wafer can be repositioned. The test head 3 is then moved downwards again to perform the wafer electromigration test once more.

[0031] The specific embodiment of the present invention has been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the embodiments described above. For those skilled in the art, various changes, modifications, substitutions, and variations made to these embodiments without departing from the principles and ideas of the present invention should still fall within the protection scope of the present invention.

Claims

1. A wafer multi-level testing device, characterized in that, The system includes a rack (1), a wafer carrier stage (2), a test head (3), and a probe card (4). The probe card (4) includes a test circuit board (41), an adjustment substrate (42), and test probes (43). The wafer carrier stage (2) and the test head (3) are both mounted on the rack (1). The wafer carrier stage (2) is configured to support and be able to translate, rotate, and heat the wafer. The test head (3) is equipped with the test circuit board (41), and the test probes (43) are connected to the test circuit board (41) and are elastic. The adjustment substrate (42) is movably connected to the test head (3), and the test probes (43) penetrate the adjustment substrate (42). The test head (3) is provided with a lateral limiting mechanism (5) and a longitudinal limiting mechanism (6). The lateral limiting mechanism (5) and the longitudinal limiting mechanism (6) are respectively connected with a lateral limiting plate (7) and a longitudinal limiting plate (8). The lateral limiting plate (7) and the longitudinal limiting plate (8) are both attached to the adjustment substrate (42). The test head (3) is provided with a positioning component (9). The positioning component (9) is used to position the adjustment substrate (42). The lateral limiting mechanism (5), the longitudinal limiting mechanism (6), the lateral limiting plate (7), the longitudinal limiting plate (8) and the positioning component (9) together constitute a precise constraint and positioning of the position and shape of the adjustment substrate (42) when performing electrical performance testing.

2. The wafer multi-level testing device according to claim 1, characterized in that, The positioning component (9) includes two positioning slots (91) symmetrically arranged on the test head (3). Two positioning rods (92) are symmetrically arranged on the adjustment base plate (42). The two positioning rods (92) are slidably installed inside the two positioning slots (91). One of the positioning slots (91) has a positioning surface (93) inside. The positioning rod (92) located inside the positioning slot (91) is in contact with the positioning surface (93). The positioning surface (93) is perpendicular to the common plane of the two positioning slots (91).

3. The wafer multi-level testing device according to claim 2, characterized in that, The positioning groove (91) is provided with a spring (10), and the two ends of the spring (10) are in contact with the positioning rod (92) and the inner wall of the positioning groove (91) respectively. The spring force direction of the spring (10) is towards the positioning surface (93).

4. The wafer multi-level testing device according to claim 3, characterized in that, The positioning surface (93) has a first inclined surface (11), and the positioning rod (92) has a second inclined surface (12) that fits with the first inclined surface (11). The height of the first inclined surface (11) is greater than the height of the second inclined surface (12).

5. A wafer multi-level testing device according to claim 2, characterized in that, The transverse limiting plate (7) and the longitudinal limiting plate (8) are made of elastic material. The transverse limiting plate (7) bends upward from the middle to both sides. The test head (3) is provided with at least 3 transverse limiting mechanisms (5), and the number of each mechanism is a base number. Multiple transverse limiting mechanisms (5) are equidistantly connected on the transverse limiting plate (7). The transverse limiting mechanism (5) located in the middle is fixedly connected to the middle of the transverse limiting plate (7). The test head (3) is provided with at least 2 longitudinal limiting mechanisms (6). The longitudinal limiting plate (8) bends upward from one end to the other along the positioning surface (93). The longitudinal limiting plate (8) is fixedly connected to the longitudinal limiting mechanism (6) at one end of the positioning surface (93). The longitudinal limiting mechanism (6) located on the side of the positioning surface (93) away from the longitudinal limiting plate (8) and the transverse limiting mechanism (5) located on both sides are provided with slide rods (13). The longitudinal limiting mechanism (6) located on the side of the positioning surface (93) away from the longitudinal limiting plate (8) is slidably connected to the longitudinal limiting plate (8) through the slide rods (13). The transverse limiting mechanism (5) located on both sides is slidably connected to the transverse limiting plate (7) through the slide rods (13).

6. The wafer multi-level testing device according to claim 5, characterized in that, The test head (3) is provided with a step (14), the height of which is 2-5 μm greater than the height of the adjustment base plate (42), and the horizontal limiting plate (7) and the vertical limiting plate (8) are both in contact with the step (14).

7. The wafer multi-level testing device according to claim 1, characterized in that, Multiple heat-conducting grooves (15) are formed on the contact surface between the test head (3) and the adjustment base plate (42).

8. The wafer multi-level testing device according to claim 1, characterized in that, The test probe (43) includes a connecting part (431), an elastic part (432), and a detection part (433). The connecting part (431) is connected to the test circuit board (41), and the detection part (433) is connected to the connecting part (431) through the elastic part (432). The elastic part (432) is bent, and the bending direction is towards the radial direction of the test circuit board (41).

9. A test method applied to the wafer multi-level testing apparatus according to any one of claims 1-8, characterized in that, Includes the following steps: S1. First, place the wafer on the wafer carrier stage (2) and preheat the wafer and probe card (4); S2. After preheating, start the transverse limiting mechanism (5), push the transverse limiting plate (7) down to squeeze the adjusting plate (42), and stop when the internal pressure of the transverse limiting mechanism (5) reaches the set value. S3. After the lateral limiting mechanism (5) stops extending, the longitudinal limiting mechanism (6) is activated, pushing the longitudinal limiting plate (8) down to squeeze the adjusting plate (42), and stopping when the internal pressure of the longitudinal limiting mechanism (6) reaches the set value. S4. After the longitudinal limiting mechanism (6) stops extending, control the wafer carrier stage (2) to adjust the wafer position and control the test head (3) to move down so that the test probe (43) contacts the wafer; S5. After the test probe (43) comes into contact with the wafer, the wafer electromigration test begins.

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