Probe station and monitoring method

Abstract

The invention relates to the field of semiconductor test equipment, and provides a probe station and a monitoring method.The probe station comprises a base, a test frame, a slide holder module, a probe module and an image acquisition module, the test frame comprises a frame body and a mounting table which are integrally formed, the frame body is connected with the base, the test frame and the base define a containing cavity, and the mounting table is arranged in the containing cavity; a through groove communicated with the accommodating cavity is formed in the mounting table; the slide holder module is located in the accommodating cavity, the slide holder module comprises a first driving assembly connected to the base and a slide holder connected to the first driving assembly, the probe module comprises a second driving assembly and a probe, the second driving assembly is connected with the mounting table, and the probe is connected with the second driving assembly; the image acquisition module is connected with the mounting table and comprises an acquisition part, and the acquisition part is located above the through groove. The monitoring method comprises four steps of calibration, inspection, calculation and output, and is used for monitoring the deformation of the probe station. According to the probe station and the monitoring method, the test result can be more reliable.

Description

Technical Field

[0001] The present application relates to the field of semiconductor testing equipment, and in particular to a probe station and a monitoring method. Background Art

[0002] In the field of semiconductor testing, probe station probes are typically used to contact the electrodes of wafer die to perform power-on testing of the die. This allows for the identification and elimination of substandard die during the wafer manufacturing phase, thereby improving packaging yield. However, current probe station test fixtures typically utilize a split connection structure, which is susceptible to slight movement or deformation under external stimulation or impact, resulting in misalignment between the probe and electrode contact position, and poor test accuracy and reliability. Summary of the Invention

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a probe station that can improve test accuracy and make test results more reliable.

[0004] The present application also proposes a monitoring method for monitoring the deformation of the probe station.

[0005] The probe station according to the embodiment of the present application includes a base, a test frame, a slide stage module, a probe module and an image acquisition module; The test frame includes an integrally formed frame body and a mounting platform. The frame body is connected to the base. The test frame and the base enclose a accommodating cavity that passes through along the Y-axis direction. Along the Z-axis direction, the mounting platform is provided with a through slot that communicates with the accommodating cavity. The stage module is located in the accommodating cavity and includes a first drive assembly and a stage. The first drive assembly is connected to the base, and the stage is connected to the output end of the first drive assembly. The first drive assembly is used to drive the stage to move along the X-axis direction and / or the Y-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other. The probe module includes a second drive assembly and a probe, the second drive assembly is connected to the mounting platform, and the probe is connected to the output end of the second drive assembly. The second drive assembly is used to drive the probe to move along the Z-axis direction so that the probe can enter or exit the accommodating cavity through the through slot; The image acquisition module is connected to the mounting platform. The image acquisition module includes an acquisition part, which is located above the through slot.

[0006] The probe station according to the embodiment of the present application has at least the following beneficial effects: the wafer stage is used to carry the wafer, the first drive component is used to drive the wafer stage to move in the accommodating cavity along the X-axis direction and / or the Y-axis direction to transport the wafer to the bottom of the through slot, and the second drive component is used to drive the probe to move along the Z-axis direction through the through slot into the accommodating cavity, so that the probe can contact the wafer on the wafer stage for testing. At the same time, the acquisition part can capture images of the wafer stage area through the through slot, which is convenient for adjusting the relative positions of the wafer stage and the probe. In addition, the wafer stage module is mounted on the frame, the probe module and the image acquisition module are mounted on the mounting table, and the frame and the mounting table are integrally formed, so that the mounting table can more effectively resist micro-movement or deformation caused by external excitation, vibration and other factors. Therefore, during the test operation, the relative positions of the wafer stage module, the probe module and the image acquisition module are more certain, thereby facilitating stable image acquisition and precise contact between the probe and the electrode, which is beneficial to improving test accuracy and reliability.

[0007] According to some embodiments of the present application, the probe station further includes a strain structure and a monitoring module. The strain structure is connected to a side of the mounting platform facing the base, and the strain structure is electrically connected to the monitoring module.

[0008] According to some embodiments of the present application, the first driving component includes an X-axis moving platform and a Y-axis moving platform. The carrier stage is connected to the X-axis moving platform. Along the X-axis direction, the X-axis moving platform is movably connected to the Y-axis moving platform. Along the Y-axis direction, the Y-axis moving platform is movably connected to the base. Along the Z-axis direction, the X-axis moving platform is located between the Y-axis moving platform and the carrier stage.

[0009] According to some embodiments of the present application, the carrier stage is rotatably connected to the first driving assembly around the Z-axis direction.

[0010] According to some embodiments of the present application, the probe station includes two probe modules, which are spaced apart and arranged at both ends of the through slot along the X-axis direction.

[0011] According to some embodiments of the present application, the probe station further includes a test module, the test module is connected to the base, the first drive assembly is provided with a test channel along the Z-axis direction, and the slide stage covers a side of the test channel away from the test module; Among them, the slide stage is a transparent structure.

[0012] The monitoring method according to an embodiment of the present application is used to monitor the deformation of the probe station in any of the above embodiments, and the monitoring method includes calibration, detection, calculation and output steps: Calibration: Based on the reference voltage of the reference branch, adjust the initial voltages of multiple monitoring branches connected in parallel with the reference branch so that each initial voltage is equal to the reference voltage; Detection: Detect the voltage of each monitoring branch after the deformation of the monitored area to obtain the strain voltage; Calculation: Calculate the strain state of each location in the monitored area based on the reference voltage and strain voltage; Output: According to the strain state, output the strain distribution diagram and / or strain distribution matrix representing the strain state.

[0013] According to the monitoring method of the embodiment of the present application, it has at least the following beneficial effects: the calibration step is used to make the initial voltage of each monitoring branch consistent to compensate for the arrangement of the strain structure, so as to facilitate the subsequent steps to uniformly measure the strain degree of the strain structure through voltage changes; the detection step is used to detect the voltage changes of each detection branch, so as to calculate the strain degree at the corresponding monitoring position of each monitoring branch in the calculation step, and then output the strain distribution diagram and / or strain distribution matrix representing the strain state. Therefore, through the monitoring method of the present application, the deformation of the probe station can be monitored in real time, which facilitates the timely termination of the detection operation when the deformation of the probe station is too large, so as to ensure the accuracy and reliability of the detection operation.

[0014] According to some embodiments of the present application, based on Calculate the strain state at each location in the area to be monitored; in, is the strain sensitivity coefficient, Indicates the The strain value of each monitoring branch, represents the reference voltage, Indicates the The strain voltage of each monitoring branch, Indicates the The value representing the strain state detected by each monitoring branch in the area to be monitored, and .

[0015] According to some embodiments of the present application, the reference branch is configured with two reference resistors connected in series, and a reference voltage is measured between the two reference resistors. Each monitoring branch is configured with a strain structure and an adjustable resistor connected in series, and the strain structure is arranged in the area to be monitored; In the calibration step, the resistance of the adjustable resistor is adjusted to be equal to the resistance of the strain structure, and an initial voltage is measured between the strain structure and the adjustable resistor.

[0016] According to some embodiments of the present application, before arranging the monitoring branch, the upper limit of the resistance of the strain structure is measured and recorded as a first resistance value, and an adjustable resistor having an upper limit of a second resistance value is selected based on the first resistance value; The first resistance value is smaller than the second resistance value.

[0017] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present application is further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1 This is a schematic diagram of the structure of the probe station according to an embodiment of the present application; Figure 2 This is a structural diagram of the wafer stage module according to an embodiment of the present application; Figure 3 This is a schematic structural diagram of the probe module according to an embodiment of the present application; Figure 4 This is a schematic diagram of the assembly of the test stand and the base according to the embodiment of the present application; Figure 5 It is an equivalent schematic diagram of the split test frame; Figure 6 This is an equivalent schematic diagram of the integrated test stand according to an embodiment of the present application; Figure 7 It is a simulation diagram of split and integrated test racks; Figure 8 This is a circuit diagram of the strain structure and monitoring module according to an embodiment of the present application; Figure 9 This is a circuit diagram of the monitoring method according to an embodiment of the present application; Figure 10 A side view of the probe station according to an embodiment of the present application; Figure 11 This is a bottom view of the probe station according to an embodiment of the present application.

[0019] Reference numerals: test stand 100 , frame 110 , accommodating cavity 111 , mounting platform 120 , through slot 121 , mounting slot 122 , base 130 ; The wafer stage module 200, the first driving assembly 210, the X-axis moving platform 211, the Y-axis moving platform 212, the test channel 213, and the wafer stage 220; Probe module 300, second driving assembly 310, probe 320; Image acquisition module 400 , image acquisition seat 410 , collector 420 , acquisition unit 421 . DETAILED DESCRIPTION

[0020] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0021] In the description of this application, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on this application.

[0022] In the description of this application, "several" means more than one, "plurality" means two or more, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The terms "first" and "second" are used solely to distinguish technical features and are not to be construed as indicating or implying relative importance, or as implicitly specifying the number or order of the technical features indicated.

[0023] In the description of this application, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in this application based on the specific content of the technical solution.

[0024] In the description of this application, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples.

[0025] The following describes the embodiments of the present application in conjunction with the accompanying drawings: refer to Figures 1 to 4According to the probe station of the embodiment of the present application, it includes a base 130, a test frame 100, a carrier stage module 200, a probe module 300 and an image acquisition module 400. The test frame 100 includes an integrally formed frame body 110 and a mounting platform 120. The frame body 110 is connected to the base 130. The test frame 100 and the base 130 enclose a accommodating cavity 111 that passes through along the Y-axis direction. Along the Z-axis direction, the mounting platform 120 is provided with a through groove 121, and the through groove 121 is connected to the accommodating cavity 111. The stage module 200 is located in the accommodating cavity 111. The stage module 200 includes a first drive component 210 and a stage 220. The first drive component 210 is connected to the base 130. The stage 220 is connected to the output end of the first drive component 210. The stage 220 is used to carry the workpiece to be measured (such as a wafer). The first drive component 210 is used to drive the stage 220 to move along the X-axis direction and / or the Y-axis direction to adjust the position of the stage 220 so that the stage 220 can move to the bottom of the through slot 121 for detection operations, or move out from under the through slot 121. The X-axis direction, the Y-axis direction and the Z-axis direction are perpendicular to each other.

[0026] The probe module 300 includes a second drive component 310 and a probe 320. The second drive component 310 is connected to the mounting table 120. The probe 320 is connected to the output end of the second drive component 310. The second drive component 310 is used to drive the probe 320 to move along the Z-axis direction so that the probe 320 can enter or exit the accommodating cavity 111 through the through slot 121. Therefore, when the first drive component 210 drives the wafer stage 220 to move to the bottom of the through slot 121, the second drive component 310 drives the probe 320 close to the wafer stage 220 so that the probe 320 contacts the electrode of the wafer core particle to realize the power-on test of the core particle. The image acquisition module 400 is connected to the mounting table 120. The image acquisition module 400 includes an acquisition part 421. The acquisition part 421 is located above the through slot 121. During the movement and testing of the probe 320, the acquisition part 421 acquires the image of the stage 220 area through the optical lens. The acquired image is transmitted to the controllers of the first drive component 210 and the second drive component 310 through the signal line. Based on the acquired image, the relative position of the stage 220 and the probe 320 can be adjusted to make the alignment of the two more accurate.

[0027] Based on the above, the one-piece structural feature of the test frame 100 in the present application, on the one hand, eliminates the assembly process between the frame 110 and the mounting table 120, and the assembly efficiency is higher. On the other hand, it enhances the overall structural rigidity of the test frame 100, so that the mounting table 120 can effectively resist the slight movement or deformation caused by external excitation, vibration and other factors. Therefore, during the testing operation, the mounting table 120 can more stably carry the probe module 300 and the image acquisition module 400, so that the wafer stage module 200, the probe module 300 and the image acquisition module 400 have a more certain relative position relationship. The image collected by the collection unit 421 can more accurately reflect the relative position of the probe 320 and the wafer core electrode. Based on the more accurate image, the alignment of the probe 320 and the core electrode can be more accurately adjusted, thereby improving the accuracy and reliability of the test.

[0028] refer to Figures 1 to 4 Specifically, during assembly, the wafer stage module 200 is first assembled with the base 130, and then the base 130 is connected to the test frame 100. The first drive assembly 210 drives the wafer stage 220 using a method including, but not limited to, a linear motor structure, a ball screw transmission structure, or a synchronous belt transmission structure. The accommodating cavity 111 is continuous along the Y-axis to avoid movement of the wafer stage 220, thereby ensuring the loading and unloading of wafers on the wafer stage 220. The second drive assembly 310 can be driven in the same manner as the first drive assembly 210, or it can use a cylinder or electric push rod as a driving structure. The acquisition unit 421 can be an acquisition structure composed of an industrial camera and a lens. When the position of the stage 220 and the probe 320 is adjusted, the image information collected by the acquisition unit 421 can provide real-time position feedback for the position adjustment of the acquisition unit 421 and the probe 320, which is beneficial for the operator or the control system to calibrate the position parameters of the stage 220 and the probe 320, so that the contact position of the probe 320 and the wafer electrode is more in line with the test requirements, and the movement positioning of the stage 220 is also more accurate.

[0029] refer to Figures 4 to 6 Compared with the solution in which the frame 110 and the mounting platform 120 are separate structures, the integrated test stand 100 of the present application has a more stable structure. The specific analysis is as follows: For the split test frame 100, the frame 110 and the mounting platform 120 are equivalent to a simply supported beam structure. For example, in the split test frame 100, the frame 110 and the mounting platform 120 are connected by bolts and other connecting parts. If the mounting platform 120 is subjected to a load along the Z-axis direction, the mounting platform 120 has a tendency to bend or deform. Bolts and other connecting parts are difficult to completely constrain the connection between the mounting platform 120 and the frame 110. Therefore, based on the principle of leverage, there will be an articulated rotational motion at the connection between the mounting platform 120 and the frame 110, that is, along the Y-axis direction, the two ends of the corresponding connection between the mounting platform 120 and the frame 110 are equivalent to hinges.

[0030] Furthermore, for the simply supported beam structure equivalent to the test frame 100, The deflection function at position is , then the uniformly distributed load The deflection function acting on the entire beam is: ; in, is the deflection, is the unit load acting on the simply supported beam, is Young's modulus, is the moment of inertia of the cross section, is the panel width.

[0031] According to the above deflection function, The maximum deflection is at (i.e., the maximum deformation of the simply supported beam), and the maximum deflection is obtained by substituting: .

[0032] For the integrally molded test frame 100 in this application, the connection between the mounting platform 120 and the frame body 110 is set to the opposite ends A and B. Based on the integrally molded structure, the deflection and rotation angle of ends A and B are 0. Taking end B as an example, the maximum deflection of the integrally molded test frame 100 in this application is calculated as follows: According to the structural equivalent effect, the B end can be equivalent to and ,in is the support force of the frame 110 on the mounting platform B end, is the bending moment of the mounting platform 120 at the B end, so ,and , and furthermore, ; The deflection function under the action is: ; The deflection function under the action is: ; Deflection function under action: ; and then, 、 、 The deflection function under the action of the resultant force is: ,Will Substituting the above resultant force deflection function, we can obtain: ; Arranged available, ; Further calculation of the maximum deformation (i.e. ), we can get ; Based on the above, the ratio of the maximum deformation between the split type and this application is: ; Therefore, the deformation of the mounting platform 120 in this application is only .

[0033] It should be noted that, in static state, unit load can be understood as unit mass and gravitational acceleration The product of; Under dynamic conditions, the unit load needs to consider the acceleration. If the acceleration under dynamic conditions is , the unit load under dynamic conditions should be Since the dynamics is based on the dynamic force balance state and linear basis, the calculation method under dynamics is the same as that under statics, and the unit load gravity acceleration is Change to dynamic acceleration That’s it, I won’t go into details here.

[0034] Reference Figure 7 The present application also provides a comparison of simulation results based on the split test frame 100 and the integrated test frame 100 of the present application. Based on the simulation results, it can be seen that the ratio of the maximum deformation of the split (B) and the integrated (A) is: 0.0098596 / 0.001923=5.13, which is close to the theoretical value, to further confirm that the integrated test frame of the present application is superior to the split test frame.

[0035] refer to Figure 1 In some embodiments, the probe station also includes a strain structure and a monitoring module. The strain structure is connected to the side of the mounting platform 120 facing the base 130, and the strain structure is electrically connected to the monitoring module. The strain structure can be a strain gauge, an optical fiber sensor, a laser sensor, or other structure that can realize deformation detection. The strain structure and the monitoring module are set to facilitate monitoring the deformation of the mounting platform 120, so as to stop the test when the mounting platform 120 produces a large deformation, thereby ensuring the accuracy and reliability of the test structure.

[0036] For example, if a strain gauge is used, the strain gauge is electrically connected to the monitoring module. When the mounting platform 120 is deformed, the strain gauge is deformed along with the mounting platform 120, thereby causing the resistance value of the strain gauge itself to change. The monitoring module monitors the strain of the mounting platform 120 by detecting the change in the resistance value of the strain gauge. If a fiber optic sensor is used, the fiber optic sensor includes a fiber Bragg grating (FBG), which is fixed to the side of the mounting platform 120 facing the base 130. When the mounting platform 120 is deformed, the fiber Bragg grating is deformed along with the mounting platform 120, causing the grating of the fiber Bragg grating to change periodically, thereby changing the wavelength of the fiber Bragg grating reflected wave. The monitoring module can monitor the deformation of the mounting platform 120 by analyzing the change in the wavelength of the reflected wave. If a laser sensor is used, the transmitting end and the receiving end of the laser sensor are relatively arranged on the base 130, and the laser beam path of the laser sensor passes through the surface of the mounting platform 120 facing the base 130. The laser sensor forms a signal connection with the monitoring module. When the mounting platform 120 is deformed, the surface position of the mounting platform 120 facing the base 130 changes, causing the phase of the laser beam after reflection on the surface to change. The monitoring module can accurately measure the slight deformation of the mounting platform 120 by measuring the phase change.

[0037] The following uses the combination of strain gauges and monitoring modules as an example to further explain the monitoring principle in this application: refer to Figure 8 and Figure 10 , along the Z-axis direction, the strain gauge is attached to the bottom of the mounting platform 120. Multiple strain gauges can be attached to the bottom of the mounting platform 120, and the strain gauges are arranged at intervals. The arrangement methods include but are not limited to: arranging at intervals along the X-axis direction, arranging at intervals along the Y-axis direction, or distributing in an array form below the mounting platform 120, so that the multiple strain gauges can correspond to different areas below the mounting platform 120 respectively, thereby realizing the monitoring of the strain conditions at various locations below the mounting platform 120.

[0038] The strain gauge is composed of multiple resistance wires arranged reciprocatingly to form a wire grid structure. When the mounting platform 120 bends downward to produce deformation, the strain gauge will deform along with the mounting platform 120. At this time, the strain gauge is stretched, and the internal resistance wire becomes thinner due to the stretching, and the resistance value of the strain gauge itself increases. The specific monitoring module includes a reference branch and multiple monitoring branches. Each monitoring branch is connected in parallel with the reference branch. The reference branch contains two reference resistors connected in series. ,and The connection point between the two reference resistors is used as the reference voltage measurement point. Taking the setting of 7 strain gauges as an example, the number of monitoring branches is the same as the number of strain gauges, and each monitoring branch is provided with an adjustable resistor connected in series with the strain gauge one-to-one, and in each monitoring branch, the voltage of the monitoring branch (such as the initial voltage and the strain voltage) is measured between the adjustable resistor and the strain gauge.

[0039] When the strain gauge is strained due to the deformation of the mounting platform 120, the resistance value of the strain gauge changes accordingly, causing the total resistance of the monitoring branch to change. Since each monitoring branch is connected in parallel with the reference branch, when the input voltage is stable, the voltage between the adjustable resistor and the strain gauge in the monitoring branch will change with the change of the total resistance of the monitoring branch. By capturing this voltage change, the monitoring module can measure the change in the resistance value of the strain gauge, and then evaluate the strain degree of the strain gauge, and ultimately realize the monitoring of the strain degree of the mounting platform 120.

[0040] It should be noted that the reference Figure 8 , if the input voltage to the monitoring module is , then in the reference branch, the voltage between the two reference resistors , Corresponding to 7 strain gauges, Corresponding to 7 adjustable resistors.

[0041] refer to Figures 1 to 4 In some embodiments, the first driving assembly 210 includes an X-axis moving platform 211 and a Y-axis moving platform 212, and the carrier stage 220 is connected to the X-axis moving platform 211. Along the X-axis direction, the X-axis moving platform 211 is movably connected to the Y-axis moving platform 212. Along the Y-axis direction, the Y-axis moving platform 212 is movably connected to the base 130. Along the Z-axis direction, the X-axis moving platform 211 is located between the Y-axis moving platform 212 and the carrier stage 220 to realize the driving of the carrier stage 220.

[0042] Specifically, one of the Y-axis mobile platform 212 and the base 130 is provided with a guide groove, and the other corresponding position is provided with a guide rail. The guide rail is slidably arranged in the guide groove to form a sliding guide fit. At the same time, a motor and a screw-nut transmission mechanism are connected to the base 130, and the nut pair of the screw-nut transmission mechanism is fixedly connected to the Y-axis mobile platform 212. When the motor is started and drives the screw to rotate, the screw-nut pair produces a linear movement along the Y-axis direction, thereby driving the Y-axis mobile platform 212 to move along the Y-axis direction relative to the base 130. Similarly, the screw-nut mechanism is also used to achieve relative movement between the X-axis mobile platform 211 and the Y-axis mobile platform 212. Specifically, the X-axis mobile platform 211 cooperates with the guide groove on the Y-axis mobile platform 212 through the guide rail, or the Y-axis mobile platform 212 cooperates with the guide groove on the X-axis mobile platform 211 through the guide rail, and relative displacement in the X-axis direction is achieved through the screw-nut transmission.

[0043] Thus, when the Y-axis moving platform 212 moves relative to the base 130, since the wafer carrier 220 is connected to the X-axis moving platform 211, and the X-axis moving platform 211 is connected to the Y-axis moving platform 212, the wafer carrier 220 can be driven to adjust its position along the Y-axis direction. When the X-axis moving platform 211 moves relative to the Y-axis moving platform 212, the position of the wafer carrier 220 can be adjusted along the X-axis direction. Through the coordinated action of the X-axis moving platform 211 and the Y-axis moving platform 212, the planar position of the wafer carrier 220 can be adjusted, so that the position to be tested of the wafer carried by the wafer carrier 220 is aligned with the through slot 121 on the mounting platform 120, thereby realizing the detection of wafer core particles at different positions on the wafer.

[0044] refer to Figures 1 to 4In some embodiments, the stage 220 is rotatably connected to the first driving assembly 210 around the Z-axis direction to achieve rotational movement of the stage 220 around the Z-axis direction, further improving the position adjustment flexibility of the stage 220.

[0045] Specifically, the first drive assembly 210 includes an X-axis mobile platform 211 and a Y-axis mobile platform 212. The stage 220 is rotatably connected to the X-axis mobile platform 211 about the Z-axis. Along the Z-axis, a circular groove is provided on the side of the X-axis mobile platform 211 near the stage 220, matching the outer periphery of the stage 220. The bottom area of ​​the stage 220 fits within this circular groove, enabling the stage 220 to rotate about the Z-axis relative to the X-axis mobile platform 211. The outer periphery of the stage 220 is provided with an annular tooth structure. A drive motor is fixedly mounted on the X-axis mobile platform 211, and the motor's output shaft is connected to the outer periphery of the stage 220 via a synchronous belt. The tension of the synchronous belt is adjusted by a tensioning bearing provided on the X-axis mobile platform to ensure that the synchronous belt maintains effective tension during transmission.

[0046] When the motor starts, the driving wheel drives the synchronous belt, which, through meshing, drives the wafer stage 220 to rotate about the Z axis, thereby adjusting the angular position of the wafer on the wafer stage 220. Thus, the position adjustment of the wafer stage 220 includes translation adjustment along the X and Y axes, as well as rotation adjustment about the Z axis. This provides both position and angle adjustment capabilities within a two-dimensional plane, further enhancing the flexibility of the wafer stage 220's position adjustment. This allows the die to be rotated to the optimal angle on the wafer to achieve more accurate alignment with the probes 320 of the probe module 300.

[0047] During the power-on test of the wafer core, after the wafer stage 220 is adjusted to the target position through the X-axis moving platform 211 and the Y-axis moving platform 212, the angle of the wafer can be further fine-tuned by rotating the wafer stage 220 around the Z-axis so that the electrode of the wafer core is completely aligned with the axis of the probe 320. This is beneficial to improving the stability of electrical signal transmission and the reliability of test results. It can also compensate for slight installation deviations of the wafer through active adjustment, thereby improving the adaptability of the probe station to complex test scenarios.

[0048] refer to Figures 1 to 4In other embodiments, in order to detect the movement and rotational strokes of the stage 220, a photoelectric sensor is provided at the end of the guide rail or around the stage 220. Specifically, the photoelectric sensor includes a transmitter and a receiver, and can adopt a beam-type or reflective structure design: for the detection of linear motion, a photoelectric sensor is installed at the end of the guide rail of the X-axis moving platform 211 or the Y-axis moving platform 212 (i.e., the travel limit position), and the transmitter and the receiver are respectively arranged on both sides of the guide rail or on the same side. When the stage 220 moves to the end of the guide rail along with the moving platform, the edge of the stage 220 or the moving platform triggers the sensor, causing it to generate an electrical signal change. For the detection of rotational stroke, an annular sensing area is provided on the circumferential edge of the stage 220, and a photoelectric sensor is installed on the corresponding X-axis moving platform 211. By detecting the scale or mark in the annular area, real-time monitoring of the rotation angle of the stage 220 is achieved.

[0049] refer to Figures 1 to 4 In some embodiments, the probe station includes two probe modules 300. Along the X-axis direction, the probe modules 300 are spaced apart at both ends of the through slot 121. Through the independent driving and coordinated cooperation of the dual probe modules 300, the probe 320 can be more accurately aligned with the electrode of the wafer core particle.

[0050] Specifically, the through slot 121 passes through the mounting table 120 and is connected to the accommodating cavity 111, and is used to expose the wafer on the wafer stage 220. Along the X-axis direction, mounting slots 122 are respectively provided at the left and right ends of the through slot 121. The second driving components 310 of the two probe modules 300 are installed in the above-mentioned mounting slots 122 one by one, and each second driving component 310 independently drives a probe 320 to move along the Z-axis direction, so that the position adjustments of the two probes 320 in the Z-axis direction are decoupled from each other (that is, the two probes 320 can have different Z-axis positions) to adapt to the differences in height or spatial position of the wafer core electrode.

[0051] Among them, each second drive assembly 310 includes a drive motor, a conveyor belt, a screw nut mechanism and a probe holder. The drive motor is fixed to the probe holder, the motor output shaft is connected to the driving wheel, and the conveyor belt surrounds the driving wheel and the driven wheel at the end of the screw to form a transmission connection. When the drive motor rotates, the conveyor belt drives the screw to rotate, and the screw nut pair converts the rotational motion into linear motion along the Z axis, thereby driving the probe 320 connected to the nut pair to move up and down independently, realizing the precise adjustment of each Z axis position, which can effectively adapt to the electrode height difference caused by factors such as warping and uneven thickness on the wafer surface.

[0052] The probe holder can adopt a precision slide structure, and its fine-tuning function is realized by a screw micrometer mechanism. The fixed base plate of the precision slide is connected to the bottom of the mounting groove 122, and the sliding table body slides with the fixed base plate through a linear guide rail. The screw micrometer is installed on one side of the fixed base plate, and the end of the screw of the micrometer is fixed to the sliding table body, thereby realizing fine-tuning of the position of the probe 320 along the X-axis direction or the Y-axis direction to compensate for the wafer placement deviation or mechanical assembly error.

[0053] refer to Figure 10 and Figure 11 In some embodiments, the probe station further includes a test module, which is connected to the base 130. Along the Z-axis direction, the first drive component 210 is provided with a test channel 213, and the carrier stage 220 covers the side of the test channel 213 away from the test module, and the carrier stage 220 is a transparent structure. Specifically, along the Z-axis direction, a through test channel 213 is provided inside the first drive component 210, and the test channel 213 is perpendicular to the bearing plane of the carrier stage 220. The carrier stage 220 covers the side of the test channel 213 away from the test module, and the carrier stage 220 is configured as a transparent structure. For example, the carrier stage 220 is made of transparent materials such as glass and quartz to ensure that the detection signal can penetrate the carrier stage 220.

[0054] The test module can be a device with optical or radiographic detection capabilities, such as a spectrometer or radiation testing system. When the wafer stage module 200, driven by the first drive assembly 210, moves directly below the mounting platform 120, the detection signal (such as light or radiation) emitted by the test module travels upward along the Z-axis through the test channel 213 and shines through the transparent wafer stage 220 onto the wafer surface, thereby enabling non-contact testing of the wafer's optical properties, material properties, and other parameters.

[0055] Thus, the probe station of the present application can realize diversified detection of wafers through the cooperation of the test module and the transparent stage 220 without removing the stage 220. Since the stage 220 is made of transparent material and covers the test channel 213, the detection signal does not need to undergo complex optical path adjustment and can directly penetrate the stage 220 to act on the wafer, reducing signal attenuation and position deviation during the detection process, which is beneficial to improving detection efficiency and data accuracy. The setting of the test channel 213 provides a dedicated transmission path for the detection signal, avoiding interference with other components and ensuring the stability of the detection process.

[0056] refer to Figure 1In other embodiments, the image acquisition module 400 further includes an image acquisition base 410 and a collector 420. The image acquisition base 410 is connected to the mounting platform 120, and the collector 420 is connected to the image acquisition base 410. The collector 420 includes a collection portion 421. The collector 420 extends along the Z-axis. The image acquisition base 410 may utilize a combination of slide rails and a precision slide table to enable coarse and fine adjustment of the position of the collector 420 along the X-axis and / or the Z-axis, thereby clearly capturing wafer images. The collector 420 may be a horizontal CCD (charge-coupled device). When two probe modules 300 are arranged in a spaced relationship along the X-axis, the collector 420 extends along the Z-axis between the two probe modules 300, such that the collection portion 421 is located between the two probe modules 300, and the probes 320 of both probe modules 300 are within the image acquisition range of the collection portion 421.

[0057] refer to Figures 1 to 10 The monitoring method according to the embodiment of the present application is used to monitor the deformation of the probe station in any of the above embodiments, specifically, to monitor the deformation of the mounting platform 120. The monitoring method includes four steps: calibration, detection, calculation, and output, as follows: Calibration: Based on the reference voltage of the reference branch, the initial voltages of multiple monitoring branches connected in parallel with the reference branch are adjusted so that each initial voltage is equal to the reference voltage. After calibration, the voltages of each monitoring branch in the initial state remain consistent, thereby compensating for the deformation of the strain structure during installation, making it easier to uniformly measure the degree of strain through voltage changes in the future.

[0058] Detection: Detect the voltage of each monitoring branch after the monitored area is deformed to obtain the strain voltage. That is, when the monitored area of ​​the mounting platform 120 is deformed, the strain structure in the corresponding area deforms along with the mounting platform 120 and changes its resistance value, causing the total resistance of the corresponding monitoring branch to change. Since each monitoring branch is connected in parallel with the reference branch, when the input voltage is stable, the voltage at the measurement point between the adjustable resistor and the strain structure in the monitoring branch will change. The changed voltage value is the strain voltage.

[0059] Calculation: Based on the reference voltage and strain voltage, the strain state of each location in the monitored area is calculated to realize the identification of deformation conditions at different locations based on the strain voltage. That is, the monitoring module uses the reference voltage determined in the calibration step as the basis, combined with the strain voltage of each monitoring branch obtained in the detection step, and performs calculations through a preset calculation model. It should be understood that the calculation model is established based on the correspondence between resistance change and voltage change, and the correspondence between resistance change of the strain structure and strain degree. It can convert the voltage change of each monitoring branch into the strain value of the corresponding strain gauge location, thereby realizing the identification of deformation conditions at different locations in the monitored area of ​​the mounting platform 120 based on the strain voltage, and obtaining the strain state at each location.

[0060] Output: Based on the strain state, the strain distribution diagram and / or strain distribution matrix representing the strain state is output. The output results facilitate the operator to directly observe the strain results. At the same time, the monitoring module can compare the strain value at each position with the preset strain upper limit. When the strain value exceeds the preset upper limit, it can promptly send a signal to stop the measurement operation, ensuring the accuracy and reliability of the test results.

[0061] Specifically, refer to Figure 8 The reference branch uses two precision resistors in series ,and , and measure the reference voltage between two precision resistors in series , is the input voltage. In each monitoring branch, is an adjustable resistor, which is connected in series with the strain structures at different positions in the monitored area. It is indicated that when the strain structure is attached, the strain structure is prone to slight deformation. Therefore, it is necessary to adjust the resistance value of the adjustable resistor of each monitoring branch so that 、 、 … , making When the strain structure deforms, the resistance value changes accordingly. Consequently, the strain voltage of the monitoring branch differs from the initial voltage. The strain voltage is the current voltage value of the detection branch after the strain structure is strained. This is used to assess the degree of strain at various locations within the monitored area. The greater the strain voltage, the greater the degree of strain.

[0062] In addition, reference Figure 9In the process of voltage detection, a multi-channel voltage acquisition card can be used to realize the synchronous acquisition of the voltage of each monitoring branch. Each acquisition channel of the multi-channel voltage acquisition card forms a one-to-one corresponding electrical connection with the monitoring point between the adjustable resistor and the strain gauge in a monitoring branch, ensuring that the voltage signal of each monitoring branch can be independently and accurately transmitted to the multi-channel voltage acquisition card. When the monitored area is deformed, the strain voltage of each monitoring branch is transmitted to the multi-channel voltage acquisition card through the corresponding acquisition channel. The multi-channel voltage acquisition card converts these analog voltage signals into digital signals for subsequent calculation and processing.

[0063] The collected digital voltage signal is transmitted to the control processing module, which incorporates a pre-set calculation model based on the relationship between the resistance change and the degree of strain, and the relationship between the resistance change and the voltage change. Because different strain voltages correspond to different resistance changes in the strain gauge, and different resistance changes correspond to different strain levels in the strain gauge, the control processing module uses this calculation model to calculate the input digital voltage signal and convert the strain voltage of each monitoring branch into strain data at the corresponding location.

[0064] After the calculations are complete, the control processing module transmits the obtained strain degree data to the display unit. The display unit processes this data according to pre-set graphical and matrixing rules, outputting a strain distribution diagram and / or strain distribution matrix representing the strain state. By observing the strain distribution diagram and / or strain distribution matrix on the display unit, operators can quickly identify locations within mounting platform 120 where strain anomalies exist, thereby screening out any abnormal parts or entire machines.

[0065] refer to Figure 8 and Figure 9 In some embodiments, based on Calculate the strain state at each location in the area to be monitored, is the strain sensitivity coefficient, Indicates the The strain value of each monitoring branch, represents the reference voltage, Indicates the The strain voltage of each monitoring branch, Indicates the The value representing the strain state detected by each monitoring branch in the area to be monitored, and Based on this formula, the strain degree of each monitoring branch can be calculated.

[0066] Specifically, the calculation formula in this application is discussed and derived: definition , under external load (such as movement or deformation of the mounting platform caused by the probe module or external excitation), the The strain value of each monitoring branch is (If the strain structure is a strain gauge, then represents the strain value of the strain gauge), so we can know ; in, The resistance value changes due to the strain generated by the strain structure. is the resistance of the strain structure in a static state, that is ; Measured The strain voltage of each monitoring branch is: ; Combine , , we can know In this calculation formula, there are different strain structures according to different materials. Therefore, by measuring the strain voltage and reference voltage of the monitoring branch, calculating the strain value of the monitoring branch, and outputting a strain distribution diagram and / or a strain distribution matrix representing the strain state, the strain degree of the strain structure can be measured, and the measurement is more convenient and quick.

[0067] refer to Figure 8 and Figure 9 In some embodiments, the reference branch is configured with two reference resistors connected in series, and a reference voltage is measured between the two reference resistors. Each monitoring branch is configured with a strain structure and an adjustable resistor connected in series, and the strain structure is arranged in the area to be monitored; wherein, in the calibration step, the resistance of the adjustable resistor is adjusted to be equal to the resistance of the strain structure, and the initial voltage is measured between the strain structure and the adjustable resistor. Compared with the solution of achieving virtual balance by presetting a correction coefficient in the monitoring module and converting the initial voltage of each monitoring branch into a value equivalent to the reference voltage according to the correction coefficient, the embodiment of the present application enables the calibration process to act directly on the monitoring branch where the strain structure is located, which can physically offset the resistance deviation of the strain structure caused by the assembly micro-change, effectively avoiding the problem of the overall balance of the reference branch being broken due to the adjustment of the reference resistor, without relying on the calculation error that may be introduced by the software algorithm to compensate, the calibration between the monitoring branches does not interfere with each other, and when multiple strain structures are arranged, the assembly micro-change of each strain structure can be accurately balanced, and the adjustment is more flexible and convenient.

[0068] refer to Figure 8 and Figure 9In some embodiments, before deploying the monitoring branch, the upper resistance limit of the strain gauge structure is measured and recorded as a first resistance value. Based on the first resistance value, an adjustable resistor with an upper resistance limit of a second resistance value is selected; the first resistance value is smaller than the second resistance value. This allows the adjustable resistor to fully offset resistance changes in the strain gauge structure caused by factors such as installation stress during assembly, facilitating deformation monitoring with a uniform voltage and ensuring monitoring accuracy.

[0069] It should be noted that the adjustable resistor can be a sliding rheostat, which changes the length of the resistor wire connected to the circuit by adjusting the position of the slider, thereby achieving continuous adjustment of the resistance value. The strain structure can be a strain gauge, and the upper limit of the resistance of the strain structure refers to the resistance value exhibited when the strain structure is stretched to its maximum extent. The measurement method can be: the strain structure is installed according to the fixed method used in actual assembly, simulated by pasting it on a test board, and then a gradually increasing tensile force is applied to the test board, causing the strain structure to be stretched along with the test board until the strain structure reaches a critical state where irreversible damage (such as wire grid breakage or substrate cracking) is imminent. At this point, the resistance value of the strain structure is detected by a resistance measuring instrument. This resistance value is the upper limit of the resistance of the strain structure (i.e., the first resistance value).

[0070] The embodiments of the present application have been described in detail above with reference to the accompanying drawings. However, the present application is not limited to the above embodiments. Various modifications can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the purpose of the present application. In addition, the embodiments of the present application and the features of the embodiments can be combined with each other unless there is a conflict.

Claims

1. A probe station, characterized in that include: base; The test stand comprises an integrally formed frame body and a mounting platform, wherein the frame body is connected to the base, the test stand and the base enclose a receiving cavity that passes through along the Y-axis direction, and the mounting platform is provided with a through slot along the Z-axis direction, the through slot communicating with the receiving cavity; a stage module located in the accommodating cavity, the stage module comprising a first drive assembly and a stage, the first drive assembly being connected to the base, the stage being connected to an output end of the first drive assembly, the first drive assembly being configured to drive the stage to move along the X-axis direction and / or the Y-axis direction, wherein the X-axis direction, the Y-axis direction, and the Z-axis direction are mutually perpendicular; The probe module includes a second drive assembly and a probe, wherein the second drive assembly is connected to the mounting platform, and the probe is connected to the output end of the second drive assembly, and the second drive assembly is used to drive the probe to move along the Z-axis direction so that the probe can enter or exit the accommodating cavity through the through slot; An image acquisition module is connected to the mounting platform. The image acquisition module includes an acquisition portion, and the acquisition portion is located above the through slot.

2. The probe station according to claim 1, characterized in that The probe station further includes a strain structure and a monitoring module. The strain structure is connected to a side of the mounting platform facing the base, and the strain structure is electrically connected to the monitoring module.

3. The probe station according to claim 1, characterized in that The first driving component includes an X-axis moving platform and a Y-axis moving platform. The carrier stage is connected to the X-axis moving platform. Along the X-axis direction, the X-axis moving platform is movably connected to the Y-axis moving platform. Along the Y-axis direction, the Y-axis moving platform is movably connected to the base. Along the Z-axis direction, the X-axis moving platform is located between the Y-axis moving platform and the carrier stage.

4. The probe station according to claim 1, characterized in that The wafer stage is rotatably connected to the first driving assembly around the Z-axis direction.

5. The probe station according to claim 1, characterized in that The probe station includes two probe modules. Along the X-axis direction, the probe modules are spaced apart and arranged at both ends of the through slot.

6. The probe station according to claim 1, characterized in that The probe station further includes a test module connected to the base. The first drive assembly is provided with a test channel along the Z-axis direction, and the slide stage covers a side of the test channel away from the test module. Wherein, the slide stage is a transparent structure.

7. A monitoring method for monitoring the deformation of the probe station according to any one of claims 1 to 6, characterized in that: The following steps are involved: Calibration: adjusting the initial voltages of a plurality of monitoring branches connected in parallel with the reference branch according to the reference voltage of the reference branch so that each of the initial voltages is equal to the reference voltage; Detection: Detecting the voltage of each monitoring branch after the monitored area is deformed to obtain the strain voltage; Calculation: Calculating the strain state of each location in the area to be monitored based on the reference voltage and the strain voltage; Output: According to the strain state, output a strain distribution diagram and / or a strain distribution matrix representing the strain state.

8. The monitoring method according to claim 7, characterized in that: based on Calculating the strain state at each location in the area to be monitored; in, is the strain sensitivity coefficient, Indicates the The strain value of each monitoring branch, represents the reference voltage, Indicates the The strain voltage of each monitoring branch, Indicates the The value representing the strain state monitored by the monitoring branch in the area to be monitored, and .

9. The monitoring method according to claim 7, characterized in that: The reference branch is configured with two reference resistors connected in series, and the reference voltage is measured between the two reference resistors. Each monitoring branch is configured with a strain structure and an adjustable resistor connected in series, and the strain structure is arranged in the area to be monitored; Wherein, in the calibration step, the resistance of the adjustable resistor is adjusted to be equal to the resistance of the strain structure, and the initial voltage is measured between the strain structure and the adjustable resistor.

10. The monitoring method according to claim 9, characterized in that: Before arranging the monitoring branch, measuring the upper limit of the resistance of the strain structure and recording it as a first resistance value, and selecting the adjustable resistor having a resistance upper limit of a second resistance value according to the first resistance value; The first resistance is smaller than the second resistance.

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