Manufacturing method of multi-carrier probe card and probe card

Abstract

The invention discloses a manufacturing method of a multi-carrier probe card. The manufacturing method comprises the following steps: firstly, carrying out reference positioning and horizontal correction on a PCB (Printed Circuit Board); the second carrier is aligned and fixed on the PCB; next, the assembly is transferred to a needle adjusting device, and a standard reference point on an integrated glass mask fixed on the device is used as a unified space reference to accurately calibrate the second carrier; and finally, by taking the calibrated second carrier and the standard reference point as a common reference, sequentially carrying out step-by-step fine adjustment and fixation on the first carrier and the third carrier, so that the needle point and needle position deviation between the carriers is less than or equal to 10 microns. According to the method, the multi-stage positioning process of fixing the intermediate carrier, performing high-precision reference calibration and performing step-by-step reference alignment is established, so that error accumulation is effectively controlled, high-precision cooperative positioning among multiple carriers is realized, and the test precision and the product yield of the probe card are improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor testing technology, and specifically to a method for manufacturing a multi-carrier probe card for testing semiconductor chips such as display driver chips, and the probe card itself. Background Technology

[0002] In the semiconductor chip manufacturing process, probe testing is a critical step to ensure chip performance and yield. As chip manufacturing processes become increasingly advanced and their structures more complex, single-carrier probe cards can no longer meet the testing requirements of multiple areas and high density. Therefore, probe cards that use multiple carriers (i.e., multiple independent tip carriers) working together have become a development trend.

[0003] However, the introduction of multi-carrier systems has brought new technical challenges: the relative position (pin position) deviation of the probe tips (i.e., probes) between different carriers is difficult to control precisely. Due to the large accumulation of carrier installation errors, existing positioning technologies cannot control the pin position deviation between multiple carriers within the 10μm required by advanced processes. This leads to misalignment of the probes with the chip pads during testing, causing problems such as test signal distortion and reduced product yield.

[0004] In existing technologies, solutions have been developed to improve the accuracy of needle position calibration. For example, published document TW111110234A discloses a needle position calibration fixture and probe calibration device. This device supports the needle position calibration piece by placing a rigid transparent substrate (such as glass, quartz, or sapphire) on a hollowed-out window of the fixture frame, thereby improving the flatness of the calibration piece and thus enhancing the accuracy of single needle position calibration. This solution primarily addresses the warping and deformation problems caused by the calibration piece being suspended. However, it does not address the fundamental challenge of how to collaboratively position multiple independent carriers on a single probe card to achieve high-precision control of their relative needle positions.

[0005] Therefore, how to achieve precise control of the needle tip position deviation (≤10μm) between multiple carriers has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for manufacturing a multi-carrier probe card. This method establishes a multi-level positioning and calibration process based on a unified high-precision benchmark, which can stably control the tip position deviation between multiple carriers within 10μm.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: On one hand, the present invention provides a method for fabricating a multi-carrier probe card, comprising the following steps: S1: PCB reference positioning and leveling. The PCB board is fixed onto a fixture, which is then placed on the projector's worktable. Reference marks on the PCB board are acquired using the projector. The fixture's orientation is adjusted to ensure the PCB board is horizontal and fixed, guaranteeing its reference plane is parallel to the projector's imaging plane, thus establishing the initial assembly reference.

[0008] S2: Second Carrier Alignment and Fixing. Adhesive material is applied to a predetermined position on the second carrier. The second carrier coated with the adhesive material is then transferred to the target assembly area on the PCB board, allowing it to adhere to the PCB board surface. The distribution area of ​​the needle tips on the second carrier and the reference marks on the PCB board are acquired in real time using a projector. Based on the imaging information, the position and angle of the second carrier are finely adjusted so that its needle tips align with the predetermined alignment marks on the PCB board. After adjustment, the adhesive material is cured, thereby fixing the second carrier to the PCB board.

[0009] S3: Precise calibration based on an integrated glass mask. The fixture, which holds the PCB board and the second carrier, is moved to and fixed within the working area of ​​the alignment device. A pre-set integrated glass mask is taken and fixed onto the reference frame of the alignment device. The alignment device uses its laser positioning system to position the integrated glass mask to ensure its stability. The image acquisition module of the alignment device captures a standard reference point on the integrated glass mask, and using this standard reference point as a unified spatial reference, the position of the fixture is adjusted so that the reference mark point on the PCB board and the alignment mark point on the second carrier coincide with the position of the standard reference point on the integrated glass mask, thereby completing the precise calibration of the second carrier in the coordinate system of the alignment device.

[0010] S4: Step-by-step alignment and fixation of the first and third carriers. Using the second carrier calibrated in step S3 and the standard reference point on the integrated glass mask as common references, the first and third carriers are aligned and adjusted sequentially. The first carrier is moved to the preset assembly position on the PCB board. Through the fine-tuning mechanism of the needle adjustment device and based on the real-time feedback from the image acquisition module, the position and angle of the first carrier are finely adjusted so that the needle position deviation between its needle tip and the needle tip of the second carrier is ≤10μm, and the alignment mark of the first carrier is aligned with the standard reference point of the integrated glass mask. After the adjustment of the first carrier is completed, the third carrier is adjusted according to the same process. After the positions of the first and third carriers are both adjusted, the first and third carriers are fixed to the PCB board using the same adhesive curing method as in step S2, thus completing the fabrication of the multi-carrier probe card.

[0011] Preferably, the integrated glass mask is a rigid transparent substrate with high hardness and high light transmittance, having a Mohs hardness ≥5, light transmittance ≥85%, and thickness ≤380μm. More preferably, the integrated glass mask is made of sapphire, quartz, or glass.

[0012] Preferably, the adhesive material is a UV-curable resin or a thermosetting resin.

[0013] Preferably, in step S4, the fine-tuning mechanism is a precision displacement stage, and the operator performs manual or semi-automatic fine-tuning based on the visual image provided by the image acquisition module.

[0014] On the other hand, the present invention provides a multi-carrier probe card manufactured using the above-described manufacturing method, namely, a multi-carrier probe card with a specific high-precision alignment structure obtained by the aforementioned method.

[0015] Preferably, in the probe card, the needle tip position deviation among the first carrier, the second carrier, and the third carrier is ≤10μm.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Extremely High Positioning Accuracy: This invention creatively proposes a multi-level positioning strategy: "PCB horizontal correction → second carrier fixing → glass mask unified benchmark calibration → subsequent carriers undergoing step-by-step fine-tuning with the fixed carrier as a reference." By fixing the second carrier first and calibrating it using a high-precision integrated glass mask, it becomes a reliable intermediate spatial benchmark. Subsequent carriers use it as a reference for alignment, greatly reducing error propagation and accumulation, and ensuring the stringent requirement of pin tip position deviation ≤10μm between multiple carriers.

[0017] 2. Excellent system stability and reliability: An integrated glass mask serves as the constant highest-precision reference throughout the entire calibration process, ensuring stable physical properties unaffected by environmental factors. All carriers are ultimately firmly bonded to the PCB board via curing, preventing positional drift during use and improving the overall mechanical stability and lifespan of the probe card.

[0018] 3. High process versatility: The core of this method lies in the process logic of benchmark establishment and step-by-step reference, rather than the specific number of carriers. Therefore, it can be flexibly adapted to the fabrication of probe cards containing three or more carriers. By adjusting the benchmark mark design, it can meet the testing needs of different chip products, and has broad application prospects.

[0019] 4. Visualized operation and improved efficiency: The entire process relies heavily on visual feedback from the projector and the needle adjustment equipment, which transforms abstract positional deviations into intuitive image information. This reduces the absolute dependence on the operator's experience, improves the accuracy of adjustments and overall production efficiency, and is conducive to standardization and mass production. Attached Figure Description

[0020] Figure 1 This is a schematic flowchart of the multi-carrier probe card fabrication method of the present invention; Figure 2 This is a front view of the multi-carrier probe card of the present invention. Figure 3 This is a schematic diagram of the assembly fixture and probe card for the projector of the present invention; Figure 4 This is a schematic diagram of the structural system of the needle adjustment device of the present invention; Figure 5 This is a schematic diagram showing the alignment of the multi-carrier probe card and the glass mask of the present invention; Figure 6 This is a schematic diagram of the PCB board structure of the present invention; Figure 7 This is a schematic diagram of the structure of the glass mask of the present invention.

[0021] Illustration: 10. PCB board; 11. Reference mark point; 12. Second alignment mark; 40. Second carrier; 401. First alignment mark; 60. Glass mask; 61. Standard reference point; 20. Fixture; 201. Leveling mechanism; 30. Projector; 50. Needle adjustment device; 51. Reference frame; 52. Image acquisition module; 53. Precision fine-tuning mechanism; 70. First carrier; 701. Third alignment mark; 80. Third carrier; 801. Fourth alignment mark; 100. Probe. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0023] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0024] Furthermore, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components; they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0026] Example: Fabrication of a three-carrier probe card for testing display driver chips.

[0027] like Figure 1-7 As shown, in this embodiment, the three-carrier probe card includes a PCB board 10, a first carrier 70, a second carrier 40, and a third carrier 80. Probes 100 are arranged on the lower surfaces of the first carrier 70, the second carrier 40, and the third carrier 80. One or more high-precision reference marks 11 are pre-fabricated on the PCB board 10, and these reference marks 11 are used for alignment with the second carrier 40. One or more high-precision second alignment marks 12 are also pre-fabricated on the PCB board, and these second alignment marks 12 are used for alignment with the tips of the probes on the second carrier 40. One or more first alignment marks 401 corresponding to the reference marks 11 are pre-fabricated on the second carrier 40. These first alignment marks 401 are used for alignment with the reference marks 11 on the PCB board 10 and the standard reference points 61 on the glass mask 60 corresponding to the second carrier 40 to install the second carrier 40. One or more high-precision third alignment marks 701 are pre-fabricated on the first carrier 70. These third alignment marks 701 are used to align with the standard reference point 61 on the glass mask 60 corresponding to the first carrier 70 for mounting the first carrier 70. One or more high-precision fourth alignment marks 801 are pre-fabricated on the third carrier 80. These fourth alignment marks 801 are used to align with the standard reference point 61 on the glass mask 60 corresponding to the third carrier 80 for mounting the third carrier 80. The marks provided on the PCB board 10, the second carrier 40, the first carrier 70, and the third carrier 80 together constitute the structural basis for achieving and ensuring high-precision alignment among multiple carriers.

[0028] In this embodiment, the method for fabricating a three-carrier probe card includes the following steps: First, execute S1. Select a PCB board 10 with a specific circuit design, on which high-precision reference marks 11 are pre-fabricated. Mount the PCB board 10 onto a special fixture 20, and place the fixture 20 on the worktable of a high-precision projector 30, with the front of the projector serving as the image display area. Turn on the projector 30, aligning its lens with the surface of the PCB board 10 to capture the image of the reference marks 11. By adjusting the leveling mechanism 201 at the bottom of the fixture 20, make the reference surface of the PCB board 10 parallel to the imaging surface of the projector 30, and then lock the fixture 20 to complete the horizontal correction and fixation of the PCB board 10.

[0029] Next, proceed to step S2. Prepare a second carrier 40, with multiple microprobes 100 implanted on its lower end face. Apply UV-curable resin to a predetermined area on the back of the second carrier 40. Use a robotic arm to transfer the second carrier 40 to the designated second carrier assembly area on the PCB board 10, allowing it to initially adhere to the surface of the PCB board 10. The projector 30 acquires images of the probe tip area on the second carrier 40 in real time, relative to the pre-set second alignment mark 12 on the PCB board 10. Use the robotic arm to finely adjust the X and Y coordinates and rotation angle θ of the second carrier 40 until the probe tip is aligned with the center of the second alignment mark 12. After confirming the position, use a UV light source to irradiate and rapidly cure the resin, thereby firmly bonding and fixing the second carrier 40 to the PCB board 10.

[0030] Subsequently, S3 is executed. The entire fixture 20 (along with the fixed PCB board 10 and the second carrier 40) is transferred to and fixed in the workstation of a high-precision alignment device 50. A one-piece sapphire glass mask 60 is taken out. The glass mask has a Mohs hardness ≥5 and a light transmittance ≥85%, and its surface is etched with standard reference points 61. The glass mask 60 is installed on the dedicated reference frame 51 of the alignment device 50. The device uses a laser positioning system (not shown in the figure) to assist in positioning and lock the glass mask 60 in place. The image acquisition module 52 (such as a CCD camera) on the alignment device 50 is activated and focused on the surface of the glass mask 60 to clearly capture the standard reference points 61. Then, the image acquisition module 52 or the fixture 20 is moved to sequentially bring the reference mark point 11 of the PCB board 10 and the first alignment mark 401 (which can be associated with the second alignment mark 12) on the second carrier 40 into the field of view. By manipulating the macroscopic displacement stage of the needle adjustment device 50, the position of the fixture 20 is adjusted until, in the image acquisition module 52, the center of the reference mark 11 and the center of the alignment mark 401 on the second carrier are completely aligned with the center of the standard reference point 61. This step ensures that the second carrier 40 is accurately positioned in the global coordinate system (based on the glass mask 60).

[0031] Finally, execute S4. Prepare the first carrier 70. Using the precisely positioned second carrier 40 and the standard reference point 61 of the glass mask 60 as a common reference, transfer the UV-coated first carrier 70 to the first carrier assembly area on the PCB board 10. Guided by the real-time magnified image from the image acquisition module 52, and through the precision fine-tuning mechanism 53 of the pin adjustment device 50 (such as a piezoelectric ceramic drive stage), the position of the first carrier 70 is adjusted with extreme precision. There are two adjustment goals: first, to ensure that the positional deviation between the pin tip at the lower end of the first carrier 70 and the pin tip of the second carrier 40 in the image is within 10μm; second, to align the center of the third alignment mark 701 of the first carrier 70 with the standard reference point 61. This is a process requiring repeated fine-tuning. After achieving the requirements, UV-curing fixes the first carrier 70. Subsequently, following the same procedure, the third carrier 80 is aligned and fixed (the procedure is the same as for the first carrier 70).

[0032] After all the carriers are fixed in place, necessary cleaning and electrical checks are performed, thus completing the fabrication of a high-precision three-carrier probe card.

[0033] Furthermore, the tip position deviation of each carrier in the above-mentioned multi-carrier probe cards was checked. Specifically, the tip displacement of the three sets of multi-carrier probe cards was detected using a Keyence VHX series digital microscope. Each probe card was measured 5 times, and the detection data were recorded as follows (unit: μm):

[0034] As can be seen from the above test data, the average tip position deviations of the three groups of probe card samples were 6.604 μm, 7.858 μm, and 9.498 μm, respectively, all strictly meeting and exceeding the design target of ≤10 μm, demonstrating the effectiveness and reliability of the fabrication method of this invention. The fluctuation range of the five test data for each group of samples was small (e.g., the range for group A was 1.32 μm, for group B it was 1.41 μm, and for group C it was 1.79 μm), indicating that the fabrication process of this invention has good consistency and repeatability.

[0035] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A method for fabricating a multi-carrier probe card, characterized in that, Includes the following steps: S1: Fix the PCB board to the fixture and perform horizontal alignment to establish an initial reference; S2: Align and fix the second carrier at the target position on the PCB board; S3: The fixture with the PCB board and the second carrier fixed thereon is transferred to the needle adjustment device. The second carrier is precisely calibrated using the standard reference point fixed on the integrated glass mask of the needle adjustment device. The position of the fixture is adjusted by observing through the image acquisition module of the needle adjustment device so that the reference mark point of the PCB board and the alignment mark of the second carrier are consistent with the position of the standard reference point. S4: Using the calibrated second carrier and the standard reference point as a common reference, the first carrier and the third carrier are aligned and fixed to the PCB board in sequence. The alignment of the first carrier and the third carrier satisfies the following conditions: the needle position deviation between the needle tip of the first carrier and the needle tip of the second carrier is ≤10μm, and the alignment mark of the first carrier is aligned with the standard reference point.

2. The method for fabricating a multi-carrier probe card according to claim 1, characterized in that, The integrated glass mask is made of sapphire, quartz, or glass.

3. The method for fabricating a multi-carrier probe card according to claim 2, characterized in that, The integrated glass mask has a Mohs hardness ≥5, light transmittance ≥85%, and thickness ≤380μm.

4. The method for fabricating a multi-carrier probe card according to claim 1, characterized in that, In steps S2 and S4, the carrier is fixed to the PCB board by applying and curing the adhesive material, wherein the curing operation is performed after the alignment is completed.

5. The method for fabricating a multi-carrier probe card according to claim 4, characterized in that, The bonding material is a UV-curable resin or a thermosetting resin.

6. The method for fabricating a multi-carrier probe card according to claim 1, characterized in that, In step S1, the reference mark point image on the PCB board is acquired by a projector to assist in completing the horizontal correction.

7. The method for fabricating a multi-carrier probe card according to claim 1, characterized in that, In step S3, the needle adjustment device is equipped with a reference frame and a laser positioning system for fixing and positioning the integrated glass mask.

8. The method for fabricating a multi-carrier probe card according to claim 1, characterized in that, In step S4, visual feedback is provided through the image acquisition module of the needle adjustment device to guide and utilize the fine-tuning mechanism of the needle adjustment device to make fine adjustments to the positions of the first carrier and the third carrier.

9. A multi-carrier probe card, characterized in that, It is manufactured using the method described in any one of claims 1 to 8.

10. The multi-carrier probe card according to claim 9, characterized in that, In the probe card, the needle tip position deviation between the first carrier, the second carrier, and the third carrier is ≤10μm.

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