A reflow soldering device for ceramic substrate and its use method

Abstract

The present application relates to a kind of reflow soldering carrier for ceramic substrate and its use method, the carrier includes base, positioning plate, mounting plate and press block, base is used to carry and fix ceramic substrate;Positioning plate covers on ceramic substrate, positioning plate is opened with several first positioning holes, the position of first positioning hole and the position of pin on ceramic substrate one-to-one correspondence, support column is placed in first positioning hole;Mounting plate covers on positioning plate, and with base and positioning plate detachable connection;Second positioning hole is opened in the position corresponding to first positioning hole of mounting plate;The upper end of press block is detachably connected with mounting plate, and lower end is equipped with elastic pad, and elastic pad is in turn through second positioning hole and first positioning hole and support column closely contact.The present application is compact in structure, easy to operate, applicable to the welding of a variety of ceramic substrate;Single welding can complete the welding of all support column, and the cost is lower;After welding, support column flatness is good, and strength is high.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor wafer testing, and in particular to a reflow soldering carrier for a ceramic substrate and a method of using the same. Background Art

[0002] The growing semiconductor industry is placing increasingly stringent requirements on wafer testing. Probe cards serve as the interface between test chips and test equipment during wafer testing. Their primary purpose is to test the electrical performance of chips before packaging, screening out defective products before proceeding to the packaging process. Specifically, the probes in the probe card make direct contact with the chip, extracting electrical signals and working with supporting instruments to complete wafer testing. Probe cards play a crucial role in both the development of early chip testing and ensuring yield during mass production.

[0003] During probe card assembly, support pins are typically secured to the MLC (ceramic substrate) using a soldering iron or adhesive. However, in 3D MEMS (Micro-Electro-Mechanical System) probe cards, storage probe cards typically feature a high number of pins (such as spring-loaded pins and probes) and a high probe compression stroke. Soldering with a soldering iron can lead to poor support pin surface flatness, low soldering strength, and poor positioning accuracy. Summary of the Invention

[0004] The present invention provides a reflow soldering carrier for a ceramic substrate and a method of using the same to solve the above technical problems.

[0005] In order to solve the above technical problems, the present invention provides a reflow soldering carrier for ceramic substrates, comprising a base, a positioning plate, a mounting plate and a pressing block.

[0006] The base is used to carry and fix the ceramic substrate;

[0007] The positioning plate is covered on the ceramic substrate, and a plurality of through first positioning holes are formed on the positioning plate. The positions of the first positioning holes correspond to the positions of the pins on the ceramic substrate, and the support columns are placed in the first positioning holes.

[0008] The mounting plate covers the positioning plate and is detachably connected to the base and the positioning plate; a second positioning hole is formed at a position of the mounting plate corresponding to the first positioning hole;

[0009] The upper end of the pressing block is detachably connected to the mounting plate, and an elastic pad is installed at the lower end. The elastic pad passes through the second positioning hole and the first positioning hole in sequence and is in close contact with the support column.

[0010] Preferably, the base is provided with a plurality of positioning pins, and the positioning plate is provided with a plurality of third positioning holes matching the positioning pins.

[0011] Preferably, the first positioning hole is composed of a circular through hole and a cross through groove with overlapping centers, and the inner diameter of the circular through hole is larger than the outer diameter of the support column.

[0012] Preferably, the pressing block is T-shaped, both ends of the transverse plate of the T-shaped pressing block are fixed to the mounting plate by bolts respectively, and the elastic pad is installed at the bottom of the longitudinal plate.

[0013] Preferably, the elastic pad is made of foamed silicone.

[0014] Preferably, the positioning plate and the mounting plate are respectively provided with a plurality of through slots and / or through holes.

[0015] Preferably, the reflow soldering vehicle for the ceramic substrate further comprises a steel screen printing plate for implanting tin on the pins of the ceramic substrate.

[0016] Preferably, the stencil printing plate is provided with a plurality of stencil printing patterns corresponding one-to-one to the pins of the ceramic substrate, the stencil printing pattern comprises a solid portion in the middle and a plurality of hollow portions surrounding the solid portion, and a partition is provided between two adjacent hollow portions.

[0017] Preferably, the hollow portion is in the shape of a sector with a missing central angle.

[0018] The present invention also provides a method for using the above-mentioned reflow soldering carrier for ceramic substrates, comprising the following steps:

[0019] Step 1: Based on the base, install the ceramic substrate, positioning plate and mounting plate so that the first positioning holes, the second positioning holes and the pins on the ceramic substrate correspond one to one;

[0020] Step 2: Place the support column into the first positioning hole of the positioning plate, and install the pressing block on the mounting plate so that the elastic pad squeezes the support column.

[0021] Compared with the prior art, the reflow soldering carrier for ceramic substrates provided by the present invention and the method of using the same have the following advantages:

[0022] 1. The carrier provided by the present invention has a compact structure, is easy to operate, occupies little space, and is suitable for MLC welding applications of various sizes, especially for welding high-needle-count storage probe cards that require a large number of spring pins;

[0023] 2. The carrier proposed by the present invention can complete the welding of all support columns in a single welding operation, which is low in cost. After welding, the support columns have good flatness and high positioning accuracy.

[0024] 3、 The tin paste coverage area is large, and the welding strength is high.

[0025] 4、 The mounting environment and transportation conditions of the carrier are not limited, and the expansibility is strong. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A structure diagram of a reflow soldering carrier for a ceramic substrate in an embodiment of the present application;

[0027] Figure 2 A front view of a reflow soldering carrier for a ceramic substrate in an embodiment of the present application;

[0028] Figure 3 A partial enlarged view of Figure 2 ;

[0029] Figure 4 An installation diagram of a base and a positioning plate in an embodiment of the present application;

[0030] Figure 5 A schematic diagram of the positional relationship between a pressing block and a support column in an embodiment of the present application;

[0031] Figure 6 A top view of a first positioning hole in an embodiment of the present application;

[0032] Figure 7 A structure diagram of a steel mesh printing plate in an embodiment of the present application;

[0033] Figure 8 A top view of a steel mesh printing pattern in an embodiment of the present application.

[0034] In the figure: 01-ceramic substrate, 02-support column; 10-base, 11-positioning pin, 20-positioning plate, 21-first positioning hole, 22-third positioning hole, 30-mounting plate, 31-second positioning hole, 40-pressing block, 41-elastic pad, 42-cross plate, 43-longitudinal plate, 50-steel mesh printing plate, 51-steel mesh printing pattern, 52-solid part, 53-hollow part, 54-barrier. DETAILED DESCRIPTION

[0035] In order to more fully describe the technical solutions of the above-mentioned application, the following specific examples are given to prove the technical effects; it should be emphasized that these examples are used to illustrate the present application and not to limit the scope of the present application.

[0036] The reflow soldering carrier for a ceramic substrate provided by the present application is used to carry and fix the ceramic substrate 01 and the support column 02, and then cooperate with the soldering furnace to complete the reflow soldering, so as to realize the connection of the ceramic substrate 01 and the support column 02. As shown inFigure 1 and Figure 2 As shown, the reflow soldering carrier includes a base 10, a positioning plate 20, a mounting plate 30 and a pressing block 40, wherein:

[0037] The base 10 is used to support and fix the ceramic substrate 01 .

[0038] The positioning plate 20 is covered on the ceramic substrate 01, and a plurality of through first positioning holes 21 are opened on the positioning plate 20. The positions of the first positioning holes 21 correspond one-to-one to the positions of the pins (PAD) on the ceramic substrate 01. The support column 02 is placed in the first positioning hole 21, thereby fixing the relative position of the ceramic substrate 01 and the support column 02.

[0039] The mounting plate 30 covers the positioning plate 20 and is detachably connected to the base 10 and the positioning plate 20. For example, bolts can be used to connect the base 10, the positioning plate 20 and the mounting plate 30 to avoid changes in the relative positions of the fixed ceramic substrate 01 and the support column 02. A second positioning hole 31 is provided at a position corresponding to the first positioning hole 21 on the mounting plate 30.

[0040] The upper end of the pressure block 40 is detachably connected to the mounting plate 30, and the lower end is mounted with an elastic pad 41. The elastic pad 41 passes through the second positioning hole 31 and the first positioning hole 21, and is in close contact with the support column 02. In other words, after the pressure block 40 is mounted on the mounting plate 30, the elastic pad 41 exerts a downward pressure on the support column 02, thereby ensuring the flatness of the support column 02.

[0041] The carrier provided by the present invention only requires a single welding operation to complete the welding of all support columns 02, which has a low cost. After welding, the support columns 02 have good flatness and high positioning accuracy. In addition, the carrier has a compact structure, is easy to operate, and occupies little space. It is suitable for MLC welding occasions of various sizes, and is particularly suitable for welding high-needle-count storage probe cards that require the use of a large number of spring needles.

[0042] In some embodiments, please refer to Figure 2 and Figure 4 The base 10 is provided with a plurality of positioning pins 11, and the positioning plate 20 is provided with a plurality of third positioning holes 22 that match the positioning pins 11, thereby positioning the relative positions of the base 10, the ceramic substrate 01 and the positioning plate 20. In some embodiments, the third positioning holes 22 can be staggered with the first positioning holes 21. Please refer to Figure 4The third positioning holes 22 are arranged in a line, and the first positioning holes 21 are also arranged in a line, with the two lines parallel and spaced apart. This approach ensures that each first positioning hole 21 has at least two positioning points (the positioning points are composed of the third positioning hole 22 and the positioning pin 11 inserted into the third positioning hole 22), thereby maximizing the accuracy of the positioning of the support column 02 and avoiding the problem of having too few positioning points or a positioning point too far from the first positioning hole 21, which may cause a first positioning hole 21 (support column 02) to be misaligned with the PAD on the ceramic substrate 01.

[0043] In some embodiments, please refer to Figure 6 The first positioning hole 21 is composed of a circular through hole and a cross groove with overlapping centers. The inner diameter of the circular through hole is larger than the outer diameter of the support column 02, which facilitates the insertion of the support column 02 into the first positioning hole 21. When the support column 02 is inserted into the first positioning hole 21, the four circular arcs can position the support column 02, and the cross groove serves to reduce the contact area between the positioning plate 20 (the inner wall of the first positioning hole 21) and the support column 02. As the reflow soldering progresses, the temperature in the furnace rises, and the solder paste changes from a solid paste to a liquid and adheres to the four sides of the support column 02. After the temperature drops, the solder paste solidifies. Due to machining errors and assembly requirements, the first positioning hole 21 is larger than the diameter of the support column 02. Therefore, when the solder paste solidifies, the support column 02 will inevitably undergo a small displacement (the displacement amount is the machining error amount), that is, the support column 02 will contact the inner wall of the first positioning hole 21. This will cause a force to exist between the ceramic substrate 01 and the positioning plate 20 when the ceramic substrate 01 is removed after the reflow soldering is completed, making it difficult to remove. The cross groove can reduce the contact area between the support column 02 and the positioning plate 20, thereby reducing the difficulty of separation.

[0044] In some embodiments, please refer to Figure 3 and Figure 5 The pressure block 40 is T-shaped, with both ends of its horizontal plate 42 bolted to the mounting plate 30. The elastic pad 41 is mounted on the bottom of the vertical plate 43. This ensures a secure connection between the pressure block 40 and the mounting plate 30. Furthermore, the vertical adjustment of the vertical plate 43 via the horizontal plate 42 allows for precise control of the elastic pad 41's planar contact with the support column 02, preventing uneven force on the support column 02. Of course, the distance from the bottom of the pressure block 40 to the top of the support column 02 should be less than the thickness of the elastic pad 41. That is, when the screws are tightened, the elastic pad 41 will be compressed to the same height, thereby ensuring the flatness of the support column 02 after welding.

[0045] In some embodiments, the elastic pad 41 can be made of foamed silicone, which can be adhered to the bottom of the pressing block 40 (longitudinal plate 43) to achieve flexible extrusion of the support column 02 by the pressing block 40. Of course, the elastic pad 41 can also be made of other materials with soft, extrudable and heat-resistant properties, as long as it can achieve the above-mentioned functions and effects.

[0046] In some embodiments, the positioning plate 20 and the mounting plate 30 are respectively provided with a plurality of through slots and / or through holes, so that the temperature in the furnace can be more evenly reflected on the ceramic substrate 01 during the reflow process. Figure 4 The through slots and / or through holes on the positioning plate 20 can be replaced by the first positioning hole 21 and the third positioning hole 22, or can be opened separately; please refer to Figure 1 The through slots and / or through holes on the mounting plate 30 may directly cover the location of the third positioning hole 22 , or may be opened at other locations.

[0047] In some embodiments, please refer to Figure 7 The reflow soldering carrier also includes a stencil printing plate 50 for soldering tin on the pins of the ceramic substrate 01. In some embodiments, the stencil printing plate 50 is provided with a plurality of stencil printing patterns 51 corresponding to the pins of the ceramic substrate 01. In this embodiment, the ceramic substrate 01 has 33 pins, the stencil printing patterns 51 are 33, and the corresponding support pillars 02 are also 33. The 33 support pillars 02 can complete the reflow soldering simultaneously. In some embodiments, please focus on Figure 8 The stencil-printed pattern 51 includes a solid portion 52 in the middle and a plurality of hollow portions 53 surrounding the solid portion 52, with a partition 54 provided between two adjacent hollow portions 53. Thus, after soldering, the PAD surface corresponding to the hollow portion 53 is covered with solder paste, while the central area corresponding to the solid portion 52 is free of solder paste. This ensures that during the reflow process after the support column 02 is installed, the solder paste does not climb upward along the internal threads of the support column 02. In some embodiments, the hollow portion 53 is a fan-shaped portion with a missing central angle. This expands the solder paste coverage area and improves the soldering strength while ensuring that the solder paste does not climb upward along the internal threads of the support column 02.

[0048] The present invention also provides a method for using the above-mentioned reflow soldering carrier for ceramic substrates, comprising the following steps:

[0049] During the pre-processing process, a stencil printing plate 50 may be used to implant tin on the pins of the ceramic substrate 01 so that each pin has sufficient solder paste.

[0050] Step 1: Based on the base 10 , install the ceramic substrate 01 , positioning plate 20 and mounting plate 30 , so that the first positioning holes 21 , the second positioning holes 31 and the pins on the ceramic substrate 01 correspond one to one to ensure the position of the support column 02 .

[0051] Step 2: Place the support column 02 into the first positioning hole 21 of the positioning plate 20 , and install the pressing block 40 on the mounting plate 30 so that the elastic pad 41 squeezes the support column 02 to ensure the flatness of the support column 02 .

[0052] After step 2 is completed, the reflow soldering carrier is assembled and the reflow soldering process can begin.

[0053] It should be noted that the support column 02 can also be placed into the first positioning hole 21 before the mounting plate 30 is installed; or it can be placed into the first positioning hole 21 through the second positioning hole 31 after the mounting plate 30 is installed; or it can be combined with the pressure block 40 and the elastic pad 41 thereon and then simultaneously placed into the first positioning hole 21. The above installation process does not affect the implementation effect of this application and is therefore not limited.

[0054] The above method can ensure that the support column 02 has good flatness and high positioning accuracy after welding, and the cost is low; there is no restriction on the installation environment and transportation conditions of the carrier, and the scalability is strong.

[0055] In summary, the present invention provides a reflow soldering carrier for ceramic substrates and a method of using the same, which carrier includes a base 10, a positioning plate 20, a mounting plate 30 and a pressing block 40, wherein the base 10 is used to carry and fix the ceramic substrate 01; the positioning plate 20 covers the ceramic substrate 01, and a plurality of through first positioning holes 21 are provided on the positioning plate 20, the positions of the first positioning holes 21 correspond one-to-one to the positions of the pins on the ceramic substrate 01, and the support column 02 is placed in the first positioning hole 21; the mounting plate 30 covers the positioning plate 20 and is detachably connected to the base 10 and the positioning plate 20; a through second positioning hole 31 is provided at a position of the mounting plate 30 corresponding to the first positioning hole 21; the upper end of the pressing block 40 is detachably connected to the mounting plate 30, and an elastic pad 41 is installed at the lower end, and the elastic pad 41 passes through the second positioning hole 31 and the first positioning hole 21 in sequence and is in close contact with the support column 02. The carrier provided by the present invention only requires a single welding operation to complete the welding of all support columns 02, which has a low cost. After welding, the support columns 02 have good flatness and high positioning accuracy. In addition, the carrier has a compact structure, is easy to operate, and occupies little space. It is suitable for MLC welding occasions of various sizes, and is particularly suitable for welding high-needle-count storage probe cards that require the use of a large number of spring needles.

[0056] Obviously, those skilled in the art may make various changes and modifications to the invention without departing from the spirit and scope of the invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A reflow soldering carrier for a ceramic substrate, characterized in that: Including base, positioning plate, mounting plate and pressure block, The base is used to carry and fix the ceramic substrate; The positioning plate is covered on the ceramic substrate, and a plurality of through first positioning holes are opened on the positioning plate. The positions of the first positioning holes correspond to the positions of the pins on the ceramic substrate one by one. The support pillars are placed in the first positioning holes. The first positioning holes are composed of a circular through hole and a cross groove with overlapping centers. The inner diameter of the circular through hole is larger than the outer diameter of the support pillar. The cross groove divides the circular through hole into four arc wall surfaces. The mounting plate covers the positioning plate and is detachably connected to the base and the positioning plate; a second positioning hole is formed at a position of the mounting plate corresponding to the first positioning hole; The upper end of the pressing block is detachably connected to the mounting plate, and an elastic pad is installed at the lower end. The elastic pad passes through the second positioning hole and the first positioning hole in sequence and is in close contact with the support column. The carrier also includes a stencil printing plate for tinning the pins of the ceramic substrate, the stencil printing plate being provided with a plurality of stencil printing patterns corresponding one to one with the pins of the ceramic substrate, the stencil printing pattern including a solid portion in the middle and a plurality of hollow portions surrounding the solid portion, a partition being provided between two adjacent hollow portions, and the hollow portion being in the shape of a sector with a missing central angle; The positioning plate and the mounting plate are respectively provided with a plurality of through slots and / or through holes.

2. The reflow soldering device for ceramic substrates according to claim 1, wherein: The base is provided with a plurality of positioning pins, and the positioning plate is provided with a plurality of third positioning holes matching the positioning pins.

3. The reflow soldering device for ceramic substrates according to claim 1, wherein: The pressing block is T-shaped, and both ends of the transverse plate of the T-shaped pressing block are fixed to the mounting plate by bolts respectively, and the elastic pad is installed at the bottom of the longitudinal plate.

4. The reflow soldering device for ceramic substrates according to claim 1, wherein: The elastic pad is made of foamed silica gel.

5. A method for using the reflow soldering carrier for a ceramic substrate according to any one of claims 1 to 4, characterized in that: The steps include: Step 1: Based on the base, install the ceramic substrate, positioning plate and mounting plate so that the first positioning holes, the second positioning holes and the pins on the ceramic substrate correspond one to one; Step 2: Place the support column into the first positioning hole of the positioning plate, and install the pressing block on the mounting plate so that the elastic pad squeezes the support column.

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