Semiconductor chilling plate welding structure and method

Abstract

The invention discloses a semiconductor chilling plate welding structure and method, and aims to overcome the defect that the performance of thermoelectric semiconductor particles is degraded due to the fact that soldering tin for assembling a semiconductor chilling plate is likely to overflow from the side edge and make contact with a bismuth telluride material. The thermoelectric module comprises two substrates and a plurality of thermoelectric semiconductor particles arranged between the two substrates, a plurality of copper bonding pads in one-to-one correspondence with the thermoelectric semiconductor particles are preassembled on the opposite surfaces of the two substrates, sunken tin filling grooves are formed in the copper bonding pads, the tin filling grooves are filled with assembling soldering tin, the tin filling grooves are completely covered by the end portions of the thermoelectric semiconductor particles, and the thermoelectric semiconductor particles are arranged on the two substrates. And the assembly soldering tin is welded with the end parts of the thermoelectric semiconductor particles. In the assembling process of the semiconductor chilling plate, soldering tin is not prone to overflowing from the side edge and making contact with the bismuth telluride material, contact reaction is avoided, the reliability of the semiconductor chilling plate is enhanced, and the amount of the soldering tin is well controlled.

Description

Technical Field

[0001] The present invention relates to thermoelectric refrigeration technology, and more specifically, to a semiconductor refrigeration plate welding structure and method. Background Art

[0002] As the reliability requirements for semiconductor refrigeration increase, the control of solder becomes a very large factor in the process of semiconductor refrigeration chip assembly. For bismuth telluride materials, copper and tin elements will react with it and greatly attenuate its performance. In addition, due to the conventional assembly process, solder easily overflows from the side and contacts the bismuth telluride material. Protecting the bismuth telluride around will affect its performance and is costly. In conventional processes, the thickness and movement position of the solder in the semiconductor refrigeration chip assembly are difficult to control, and it will bulge and bypass the protective nickel layer to directly contact the thermoelectric semiconductor particles, causing the performance of the thermoelectric semiconductor particles to attenuate. Summary of the invention

[0003] In order to overcome the above-mentioned shortcomings, the present invention provides a semiconductor refrigeration plate welding structure and method. During the assembly process of the semiconductor refrigeration plate, the solder is not easy to overflow from the side and contact the bismuth telluride material, thereby avoiding contact reaction, enhancing the reliability of the semiconductor refrigeration plate, and well controlling the amount of solder.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions: a semiconductor refrigeration plate welding structure, comprising two substrates and a plurality of thermoelectric semiconductor particles arranged between the two substrates, a plurality of copper soldering pads corresponding to the thermoelectric semiconductor particles are pre-installed on the opposite surfaces of the two substrates, a sunken tin filling groove is arranged on the copper soldering pad, the tin filling groove is filled with assembly solder, the ends of the thermoelectric semiconductor particles completely cover the tin filling groove, and the assembly solder is welded to the ends of the thermoelectric semiconductor particles.

[0005] In the semiconductor refrigeration plate welding structure of the present patent application, a copper pad is first pre-installed on a substrate, and assembly solder is filled in a tin filling groove on the copper pad. The ends of the thermoelectric semiconductor particles are attached to the surface of the copper pad, and the ends of the thermoelectric semiconductor particles completely cover the tin filling groove. After heating, the assembly solder is welded to the ends of the thermoelectric semiconductor particles. The solder is not easy to overflow from the side and contact the bismuth telluride material of the thermoelectric semiconductor particles, thereby preventing the tin element from reacting with the bismuth telluride material to cause the performance of the thermoelectric semiconductor particles to decay.

[0006] During the assembly process of the semiconductor refrigeration chip, the solder is not easy to overflow from the side and contact the bismuth telluride material, thus avoiding contact reaction, enhancing the reliability of the semiconductor refrigeration chip, and well controlling the amount of solder.

[0007] Preferably, a soldering layer is provided on the inner wall of the tin-filling tank and on the surface of the copper pad facing the thermoelectric semiconductor particles. The soldering layer includes a protective nickel layer and a metal plating layer. The assembly solder is bonded and connected to the metal plating layer.

[0008] The protective nickel layer protects the copper pads and prevents oxidation and corrosion on the surface of the copper pads. The metal plating ensures the reliability of welding.

[0009] Preferably, welding layers are provided on both end surfaces of the thermoelectric semiconductor particles, the welding layers comprising a protective nickel layer and a metal plating layer, and the assembly solder is bonded and connected to the metal plating layer.

[0010] The protective nickel layer protects the thermoelectric semiconductor particles, and the metal plating is beneficial to improving the reliability of welding between the thermoelectric semiconductor and the assembly solder.

[0011] Preferably, the edge of the soldering layer on the surface of the copper pad protrudes outward to form a circle of positioning flange.

[0012] During the process of buckling the thermoelectric semiconductor particles and the substrate, the positioning flange limits the thermoelectric semiconductor particles and prevents the end faces of the thermoelectric semiconductor particles from deviating from the assembly solder.

[0013] Preferably, the end faces of the thermoelectric semiconductor particles are placed within the range surrounded by the positioning flange and can be moved to any position, and the end faces of the thermoelectric semiconductor particles always completely cover the tin filling groove.

[0014] The end faces of the thermoelectric semiconductor particles always completely cover the tin-filling groove, and during the heating and welding process, the molten assembly solder is prevented from flowing outward from the edges of the end faces of the thermoelectric semiconductor particles.

[0015] Preferably, sinking grooves are arranged on the opposite surfaces of the two substrates, the sinking grooves are arranged in one-to-one correspondence with the copper pads, and the copper pads are embedded in the sinking grooves.

[0016] The arrangement of the sinker groove facilitates the pre-installation of the copper pad onto the substrate.

[0017] Preferably, a circuit selection groove is provided on the surface of the substrate opposite to the thermoelectric semiconductor particles, and a circuit selection groove is provided between two adjacent front and rear copper pads and between two adjacent left and right copper pads. The circuit selection groove is empty or circuit solder is filled in the empty circuit selection groove to achieve disconnection or conduction of adjacent copper pads.

[0018] The setting of the loop selection groove facilitates the electrical connection between different thermoelectric semiconductor particles, thereby realizing the electrical connection of the entire semiconductor cooling sheet. The conduction of adjacent copper pads is achieved by filling the loop solder, which is convenient and reliable.

[0019] A semiconductor refrigeration plate welding method realizes the welding of a semiconductor refrigeration plate welding structure, comprising the following steps: S1, processing a plurality of sinking grooves and loop selection grooves on a substrate; S2, installing a copper soldering pad in the sinking groove; S3, filling the tin filling groove on the copper soldering pad with assembly solder; S4, placing thermoelectric semiconductor particles at corresponding positions on the substrate; S5, heating the assembled substrate and the thermoelectric semiconductor particles together, and connecting the thermoelectric semiconductor particles and the substrate together through the assembly solder after cooling.

[0020] In this patent application, the bismuth telluride material of the assembled solder and thermoelectric semiconductor particles is isolated from the structure to avoid contact reaction, thereby ensuring the performance of the semiconductor refrigeration plate. The loop selection groove is selectively filled with loop solder according to the required position to form a complete loop and realize a variety of different loop designs. The sinking groove and the loop selection groove can be formed by directly opening holes on the substrate, without the need to open the mold substrate, reducing costs and having good versatility. By controlling the size and depth of the sinking groove and the loop selection groove, the amount of tin used can be controlled.

[0021] Preferably, in the S3 process, loop solder is filled in the loop selection groove between two copper pads that need to be connected to each other.

[0022] The loop soldering and assembly soldering are both performed in S3. In S5, the loop soldering and assembly soldering are heated simultaneously to complete reliable welding.

[0023] Another solution is to fill the loop solder in the loop selection groove between the two copper pads that need to be connected to each other after S5.

[0024] After the thermoelectric semiconductor particles and the assembly solder are welded, the loop solder is filled.

[0025] Compared with the prior art, the present invention has the following beneficial effects: (1) during the semiconductor cooling plate assembly process, the solder is not easy to overflow from the side and contact the bismuth telluride material, thus avoiding contact reaction, enhancing the reliability of the semiconductor cooling plate, and well controlling the amount of solder; (2) the end faces of the thermoelectric semiconductor particles always completely cover the tin filling groove, and during the heating and welding process, the molten assembly solder is prevented from flowing out from the edge of the end faces of the thermoelectric semiconductor particles; (3) during the buckling process of the thermoelectric semiconductor particles and the substrate, the positioning flange plays a limiting role on the thermoelectric semiconductor particles, preventing the end faces of the thermoelectric semiconductor particles from deviating from the assembly solder. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the present invention.

[0027] Figure 2 It is an exploded view of the present invention.

[0028] Figure 3 It is a cross-sectional view of the present invention.

[0029] Figure 4 The present invention Figure 3 Enlarged view of point I in the middle.

[0030] Figure 5 It is a top view of the substrate of the present invention.

[0031] Figure 6 It is a bottom view of the substrate of the present invention.

[0032] Figure 7 It is a schematic diagram of the substrate structure of the present invention.

[0033] Figure 8 It is a schematic diagram of the copper pad structure of Example 3 of the present invention.

[0034] In the figure: 1. substrate, 2. thermoelectric semiconductor particles, 3. copper pad, 4. tin filling groove, 5. assembly solder, 6. welding layer, 7. protective nickel layer, 8. metal plating, 9. tin containing groove, 10. positioning flange, 11. sinking groove, 12. loop selection groove, 13. loop solder. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further described in detail below through specific embodiments and in conjunction with the accompanying drawings: Embodiment 1: A semiconductor refrigeration plate welding structure (see attached Figure 1 To Attachment Figure 7 ), comprising two substrates 1 and a plurality of thermoelectric semiconductor particles 2 arranged between the two substrates 1, the plurality of thermoelectric semiconductor particles 2 are distributed in a rectangular array, the ends of the thermoelectric semiconductor particles 2 are all square, a plurality of copper pads 3 corresponding to the thermoelectric semiconductor particles 2 are pre-installed on the opposite surfaces of the two substrates 1, a sunken tin-filling groove 4 is arranged on the copper pad 3, the tin-filling groove 4 is filled with assembly solder 5, the assembly solder 5 fills the tin-filling groove 4, the ends of the thermoelectric semiconductor particles 2 are attached to the surface of the copper pad 3, the ends of the thermoelectric semiconductor particles 2 completely cover the tin-filling groove 4, and the assembly solder 5 is welded to the ends of the thermoelectric semiconductor particles 2.

[0036] A soldering layer 6 is provided on the inner wall of the tin-filling groove 4 and on the surface of the copper pad 3 facing the thermoelectric semiconductor particles 2. The soldering layer 6 includes a protective nickel layer 7 and a metal plating layer 8. The protective nickel layer 7 is provided between the surface of the copper pad 3 and the metal plating layer 8. The metal plating layer 8 is a gold plating layer or a tin plating layer. The assembly solder 5 is bonded and connected to the metal plating layer 8. The protective nickel layer 7 protects the copper pad 3 and prevents oxidation and corrosion on the surface of the copper pad 3. The metal plating layer 8 ensures the reliability of welding.

[0037] A welding layer 6 is provided on both end surfaces of the thermoelectric semiconductor particle 2, and the welding layer 6 includes a protective nickel layer 7 and a metal plating layer 8. The protective nickel layer 7 is provided between the end surface of the thermoelectric semiconductor particle 2 and the metal plating layer 8, and the metal plating layer 8 is a gold plating layer or a tin plating layer. The assembly solder 5 is bonded and connected to the metal plating layer 8. The protective nickel layer 7 protects the thermoelectric semiconductor particle 2, and the metal plating layer 8 is conducive to improving the reliability of welding the thermoelectric semiconductor and the assembly solder 5.

[0038] The edge of the welding layer 6 on the surface of the copper pad 3 protrudes outward to form a circle of positioning flanges 10, and the positioning flanges 10 are in a square frame structure. During the buckling process of the thermoelectric semiconductor particles 2 and the substrate 1, the positioning flanges 10 limit the thermoelectric semiconductor particles 2 to prevent the end faces of the thermoelectric semiconductor particles 2 from deviating from the assembly solder 5. The contour area of ​​the end faces of the thermoelectric semiconductor particles 2 is larger than the opening of the tin filling groove 4. The end faces of the thermoelectric semiconductor particles 2 are placed within the range surrounded by the positioning flanges 10 and moved to any position, and the end faces of the thermoelectric semiconductor particles 2 always completely cover the tin filling groove 4.

[0039] The two substrates 1 are provided with a sinking groove 11 on the opposite surfaces thereof, and the sinking groove 11 is provided in a one-to-one correspondence with the copper pad 3, and the copper pad 3 is embedded in the sinking groove 11. The setting of the sinking groove 11 facilitates the pre-installation of the copper pad 3 on the substrate 1. The substrate 1 is provided with a circuit selection groove 12 on the surface opposite to the thermoelectric semiconductor particles 2, and a circuit selection groove 12 is provided between the two adjacent copper pads 3 in the front and back and between the two adjacent copper pads 3 in the left and right, and the circuit selection groove 12 is connected between the two adjacent sinking grooves 11. The circuit selection groove 12 is vacant or the circuit solder 13 is filled in the vacant circuit selection groove 12 to realize the disconnection or conduction of the adjacent copper pads 3. The setting of the circuit selection groove 12 facilitates the electrical connection between different thermoelectric semiconductor particles 2, thereby realizing the electrical connection of the entire semiconductor refrigeration plate. The conduction of the adjacent copper pads 3 is realized by filling the circuit solder 13, which is convenient and reliable.

[0040] A semiconductor refrigeration plate welding method realizes the welding of a semiconductor refrigeration plate welding structure, comprising the following steps: S1, processing a plurality of sinking grooves 11 and circuit selection grooves 12 on a substrate 1; processing a plurality of sinking grooves 11 arranged in a rectangular array on the front side of the substrate 1, processing a plurality of circuit selection grooves 12 arranged in a rectangular array on the back side of the substrate 1, and providing a circuit selection groove 12 between two adjacent sinking grooves 11 in front and back and between two adjacent sinking grooves 11 in the upper and lower directions.

[0041] S2, install the copper pad 3 into the sinking groove 11; drill a solder groove on the copper pad 3 in advance, and plate a protective nickel layer 7 and a metal plating layer 8 on the surface of the copper pad 3 corresponding to the side wall, bottom surface and opening end of the solder groove in sequence, and the metal plating layer 8 is a gold plating layer or a tin plating layer; then pre-install the copper pad 3 into the sinking groove 11 on the substrate 1.

[0042] S3, fill the assembly solder 5 in the tin filling groove 4 on the copper pad 3; and at the same time fill the loop solder 13 in the loop selection groove 12 between the two copper pads 3 that need to be connected to each other. The loop solder 13 welds the two adjacent copper pads 3 together to achieve electrical connection.

[0043] S4, placing the thermoelectric semiconductor particles 2 at corresponding positions on the substrate 1; two ends of the thermoelectric semiconductor particles 2 are respectively bonded to the assembly solders 5 on the two substrates 1.

[0044] S5, the assembled substrate 1 and the thermoelectric semiconductor particles 2 are heated together, and the assembly solder 5 and the loop solder 13 are melted to achieve welding of the substrate 1 and the thermoelectric semiconductor particles 2, and welding of two adjacent copper pads 3. After cooling, the thermoelectric semiconductor particles 2 and the substrate 1 are connected together by the assembly solder 5.

[0045] In this patent application, the assembly solder 5 and the bismuth telluride material of the thermoelectric semiconductor particles 2 are isolated from the structure to avoid contact reaction, thereby ensuring the performance of the semiconductor refrigeration plate. The loop selection groove 12 is selectively filled with loop solder 13 according to the required position to form a complete loop and realize a variety of different loop designs. The sinking groove 11 and the loop selection groove 12 can be formed by directly opening a hole on the substrate 1, and there is no need to open the mold substrate 1, which reduces costs and has good versatility. By controlling the size and depth of the sinking groove 11 and the loop selection groove 12, the amount of tin used can be controlled.

[0046] Embodiment 2: A semiconductor refrigeration plate welding structure (see attached Figure 1 To Attachment Figure 7 ), comprising two substrates 1 and a plurality of thermoelectric semiconductor particles 2 arranged between the two substrates 1, the plurality of thermoelectric semiconductor particles 2 are distributed in a rectangular array, the ends of the thermoelectric semiconductor particles 2 are all square, a plurality of copper pads 3 corresponding to the thermoelectric semiconductor particles 2 are pre-installed on the opposite surfaces of the two substrates 1, a sunken tin-filling groove 4 is arranged on the copper pad 3, the tin-filling groove 4 is filled with assembly solder 5, the assembly solder 5 fills the tin-filling groove 4, the ends of the thermoelectric semiconductor particles 2 are attached to the surface of the copper pad 3, the ends of the thermoelectric semiconductor particles 2 completely cover the tin-filling groove 4, and the assembly solder 5 is welded to the ends of the thermoelectric semiconductor particles 2.

[0047] A soldering layer 6 is provided on the inner wall of the tin-filling groove 4 and on the surface of the copper pad 3 facing the thermoelectric semiconductor particles 2. The soldering layer 6 includes a protective nickel layer 7 and a metal plating layer 8. The protective nickel layer 7 is provided between the surface of the copper pad 3 and the metal plating layer 8. The metal plating layer 8 is a gold plating layer or a tin plating layer. The assembly solder 5 is bonded and connected to the metal plating layer 8. The protective nickel layer 7 protects the copper pad 3 and prevents oxidation and corrosion on the surface of the copper pad 3. The metal plating layer 8 ensures the reliability of welding.

[0048] A welding layer 6 is provided on both end surfaces of the thermoelectric semiconductor particle 2, and the welding layer 6 includes a protective nickel layer 7 and a metal plating layer 8. The protective nickel layer 7 is provided between the end surface of the thermoelectric semiconductor particle 2 and the metal plating layer 8, and the metal plating layer 8 is a gold plating layer or a tin plating layer. The assembly solder 5 is bonded and connected to the metal plating layer 8. The protective nickel layer 7 protects the thermoelectric semiconductor particle 2, and the metal plating layer 8 is conducive to improving the reliability of welding the thermoelectric semiconductor and the assembly solder 5.

[0049] The edge of the welding layer 6 on the surface of the copper pad 3 protrudes outward to form a circle of positioning flanges 10, and the positioning flanges 10 are in a square frame structure. During the buckling process of the thermoelectric semiconductor particles 2 and the substrate 1, the positioning flanges 10 limit the thermoelectric semiconductor particles 2 to prevent the end faces of the thermoelectric semiconductor particles 2 from deviating from the assembly solder 5. The contour area of ​​the end faces of the thermoelectric semiconductor particles 2 is larger than the opening of the tin filling groove 4. The end faces of the thermoelectric semiconductor particles 2 are placed within the range surrounded by the positioning flanges 10 and moved to any position, and the end faces of the thermoelectric semiconductor particles 2 always completely cover the tin filling groove 4.

[0050] The two substrates 1 are provided with a sinking groove 11 on the opposite surfaces thereof, and the sinking groove 11 is provided in a one-to-one correspondence with the copper pad 3, and the copper pad 3 is embedded in the sinking groove 11. The setting of the sinking groove 11 facilitates the pre-installation of the copper pad 3 on the substrate 1. The substrate 1 is provided with a circuit selection groove 12 on the surface opposite to the thermoelectric semiconductor particles 2, and a circuit selection groove 12 is provided between the two adjacent copper pads 3 in the front and back and between the two adjacent copper pads 3 in the left and right, and the circuit selection groove 12 is connected between the two adjacent sinking grooves 11. The circuit selection groove 12 is vacant or the circuit solder 13 is filled in the vacant circuit selection groove 12 to realize the disconnection or conduction of the adjacent copper pads 3. The setting of the circuit selection groove 12 facilitates the electrical connection between different thermoelectric semiconductor particles 2, thereby realizing the electrical connection of the entire semiconductor refrigeration plate. The conduction of the adjacent copper pads 3 is realized by filling the circuit solder 13, which is convenient and reliable.

[0051] A semiconductor refrigeration plate welding method realizes the welding of a semiconductor refrigeration plate welding structure, comprising the following steps: S1, processing a plurality of sinking grooves 11 and circuit selection grooves 12 on a substrate 1; processing a plurality of sinking grooves 11 arranged in a rectangular array on the front side of the substrate 1, processing a plurality of circuit selection grooves 12 arranged in a rectangular array on the back side of the substrate 1, and providing a circuit selection groove 12 between two adjacent sinking grooves 11 in front and back and between two adjacent sinking grooves 11 in the upper and lower directions.

[0052] S2, install the copper pad 3 into the sinking groove 11; drill a solder groove on the copper pad 3 in advance, and plate a protective nickel layer 7 and a metal plating layer 8 on the surface of the copper pad 3 corresponding to the side wall, bottom surface and opening end of the solder groove in sequence, and the metal plating layer 8 is a gold plating layer or a tin plating layer; then pre-install the copper pad 3 into the sinking groove 11 on the substrate 1.

[0053] S3, filling the solder filling groove 4 on the copper pad 3 with assembly solder 5.

[0054] S4, placing the thermoelectric semiconductor particles 2 at corresponding positions on the substrate 1; two ends of the thermoelectric semiconductor particles 2 are respectively bonded to the assembly solders 5 on the two substrates 1.

[0055] S5, the assembled substrate 1 and the thermoelectric semiconductor particles 2 are heated together, and the assembly solder 5 is melted to realize the welding of the substrate 1 and the thermoelectric semiconductor particles 2. After cooling, the thermoelectric semiconductor particles 2 and the substrate 1 are connected together by the assembly solder 5.

[0056] After S5, the loop selection groove 12 between the two copper pads 3 that need to be connected to each other is filled with melted loop solder 13. After cooling, the loop solder 13 welds the two adjacent copper pads 3 together to achieve electrical connection.

[0057] In this patent application, the assembly solder 5 and the bismuth telluride material of the thermoelectric semiconductor particles 2 are isolated from the structure to avoid contact reaction, thereby ensuring the performance of the semiconductor refrigeration plate. The loop selection groove 12 is selectively filled with loop solder 13 according to the required position to form a complete loop and realize a variety of different loop designs. The sinking groove 11 and the loop selection groove 12 can be formed by directly opening a hole on the substrate 1, and there is no need to open the mold substrate 1, which reduces costs and has good versatility. By controlling the size and depth of the sinking groove 11 and the loop selection groove 12, the amount of tin used can be controlled.

[0058] Embodiment 3: A semiconductor refrigeration plate welding structure (see attached Figure 1 , Attachment Figure 2 , Attachment Figure 5 To Attachment Figure 8 ), comprising two substrates 1 and a plurality of thermoelectric semiconductor particles 2 arranged between the two substrates 1, the plurality of thermoelectric semiconductor particles 2 are distributed in a rectangular array, the ends of the thermoelectric semiconductor particles 2 are all square, a plurality of copper pads 3 corresponding to the thermoelectric semiconductor particles 2 are pre-installed on the opposite surfaces of the two substrates 1, a sunken tin-filling groove 4 is arranged on the copper pad 3, the tin-filling groove 4 is filled with assembly solder 5, the assembly solder 5 fills the tin-filling groove 4, the ends of the thermoelectric semiconductor particles 2 are attached to the surface of the copper pad 3, the ends of the thermoelectric semiconductor particles 2 completely cover the tin-filling groove 4, and the assembly solder 5 is welded to the ends of the thermoelectric semiconductor particles 2.

[0059] A welding layer 6 is provided on the inner wall of the tin-filling groove 4 and on the surface of the copper pad 3 facing the thermoelectric semiconductor particle 2. The welding layer 6 includes a protective nickel layer 7 and a metal plating layer 8. The protective nickel layer 7 is provided between the surface of the copper pad 3 and the metal plating layer 8. The metal plating layer 8 is a gold plating layer or a tin plating layer. The assembly solder 5 is bonded and connected to the metal plating layer 8. A plurality of tin-containing grooves 9 are provided on the surface of the metal plating layer 8 near the edge of the tin-filling groove 4, and the end surface of the thermoelectric semiconductor particle 2 covers the tin-containing grooves 9. The solder accidentally leaked during the heating process of the assembly solder 5 can be accommodated in the tin-containing grooves 9 to prevent the solder from leaking from the side of the end surface of the thermoelectric semiconductor particle 2. The protective nickel layer 7 protects the copper pad 3 and prevents the surface of the copper pad 3 from oxidation and corrosion. The metal plating layer 8 ensures the reliability of welding.

[0060] A welding layer 6 is provided on both end surfaces of the thermoelectric semiconductor particle 2, and the welding layer 6 includes a protective nickel layer 7 and a metal plating layer 8. The protective nickel layer 7 is provided between the end surface of the thermoelectric semiconductor particle 2 and the metal plating layer 8, and the metal plating layer 8 is a gold plating layer or a tin plating layer. The assembly solder 5 is bonded and connected to the metal plating layer 8. The protective nickel layer 7 protects the thermoelectric semiconductor particle 2, and the metal plating layer 8 is conducive to improving the reliability of welding the thermoelectric semiconductor and the assembly solder 5.

[0061] The edge of the welding layer 6 on the surface of the copper pad 3 protrudes outward to form a circle of positioning flanges 10, and the positioning flanges 10 are in a square frame structure. During the buckling process of the thermoelectric semiconductor particles 2 and the substrate 1, the positioning flanges 10 limit the thermoelectric semiconductor particles 2 to prevent the end faces of the thermoelectric semiconductor particles 2 from deviating from the assembly solder 5. The contour area of ​​the end faces of the thermoelectric semiconductor particles 2 is larger than the opening of the tin filling groove 4. The end faces of the thermoelectric semiconductor particles 2 are placed within the range surrounded by the positioning flanges 10 and moved to any position, and the end faces of the thermoelectric semiconductor particles 2 always completely cover the tin filling groove 4.

[0062] The two substrates 1 are provided with a sinking groove 11 on the opposite surfaces thereof, and the sinking groove 11 is provided in a one-to-one correspondence with the copper pad 3, and the copper pad 3 is embedded in the sinking groove 11. The setting of the sinking groove 11 facilitates the pre-installation of the copper pad 3 on the substrate 1. The substrate 1 is provided with a circuit selection groove 12 on the surface opposite to the thermoelectric semiconductor particles 2, and a circuit selection groove 12 is provided between the two adjacent copper pads 3 in the front and back and between the two adjacent copper pads 3 in the left and right, and the circuit selection groove 12 is connected between the two adjacent sinking grooves 11. The circuit selection groove 12 is vacant or the circuit solder 13 is filled in the vacant circuit selection groove 12 to realize the disconnection or conduction of the adjacent copper pads 3. The setting of the circuit selection groove 12 facilitates the electrical connection between different thermoelectric semiconductor particles 2, thereby realizing the electrical connection of the entire semiconductor refrigeration plate. The conduction of the adjacent copper pads 3 is realized by filling the circuit solder 13, which is convenient and reliable.

[0063] A semiconductor refrigeration plate welding method realizes the welding of a semiconductor refrigeration plate welding structure, comprising the following steps: S1, processing a plurality of sinking grooves 11 and circuit selection grooves 12 on a substrate 1; processing a plurality of sinking grooves 11 arranged in a rectangular array on the front side of the substrate 1, processing a plurality of circuit selection grooves 12 arranged in a rectangular array on the back side of the substrate 1, and providing a circuit selection groove 12 between two adjacent sinking grooves 11 in front and back and between two adjacent sinking grooves 11 in the upper and lower directions.

[0064] S2, install the copper pad 3 into the sinking groove 11; drill a solder groove on the copper pad 3 in advance, and plate a protective nickel layer 7 and a metal plating layer 8 on the surface of the copper pad 3 corresponding to the side wall, bottom surface and opening end of the solder groove in sequence, and the metal plating layer 8 is a gold plating layer or a tin plating layer; then pre-install the copper pad 3 into the sinking groove 11 on the substrate 1.

[0065] S3, fill the assembly solder 5 in the tin filling groove 4 on the copper pad 3; and at the same time fill the loop solder 13 in the loop selection groove 12 between the two copper pads 3 that need to be connected to each other. The loop solder 13 welds the two adjacent copper pads 3 together to achieve electrical connection.

[0066] S4, placing the thermoelectric semiconductor particles 2 at corresponding positions on the substrate 1; two ends of the thermoelectric semiconductor particles 2 are respectively bonded to the assembly solders 5 on the two substrates 1.

[0067] S5, the assembled substrate 1 and the thermoelectric semiconductor particles 2 are heated together, and the assembly solder 5 and the loop solder 13 are melted to achieve welding of the substrate 1 and the thermoelectric semiconductor particles 2, and welding of two adjacent copper pads 3. After cooling, the thermoelectric semiconductor particles 2 and the substrate 1 are connected together by the assembly solder 5.

[0068] In this patent application, the assembly solder 5 and the bismuth telluride material of the thermoelectric semiconductor particles 2 are isolated from the structure to avoid contact reaction, thereby ensuring the performance of the semiconductor refrigeration plate. The loop selection groove 12 is selectively filled with loop solder 13 according to the required position to form a complete loop and realize a variety of different loop designs. The sinking groove 11 and the loop selection groove 12 can be formed by directly opening a hole on the substrate 1, and there is no need to open the mold substrate 1, which reduces costs and has good versatility. By controlling the size and depth of the sinking groove 11 and the loop selection groove 12, the amount of tin used can be controlled.

[0069] The above-described embodiments are only preferred solutions of the present invention and are not intended to limit the present invention in any form. Other variations and modifications are possible without exceeding the technical solutions described in the claims.

Claims

1. A semiconductor refrigeration plate welding structure, comprising two substrates and a plurality of thermoelectric semiconductor particles arranged between the two substrates, characterized in that: A plurality of copper pads corresponding to the thermoelectric semiconductor particles are pre-installed on the opposite surfaces of the two substrates. A sunken tin-filling groove is provided on the copper pad. The tin-filling groove is filled with assembly solder. The ends of the thermoelectric semiconductor particles completely cover the tin-filling groove. The assembly solder is welded to the ends of the thermoelectric semiconductor particles.

2. A semiconductor refrigeration plate welding structure according to claim 1, characterized in that: A welding layer is arranged on the inner wall of the tin-filling tank and on the surface of the copper pad facing the thermoelectric semiconductor particles. The welding layer includes a protective nickel layer and a metal plating layer. The assembly solder is bonded and connected to the metal plating layer.

3. The semiconductor refrigeration plate welding structure according to claim 1 is characterized in that: Welding layers are arranged on both end surfaces of the thermoelectric semiconductor particles. The welding layers include a protective nickel layer and a metal plating layer. The assembly solder is bonded and connected with the metal plating layer.

4. A semiconductor refrigeration plate welding structure according to claim 2, characterized in that: The edge of the solder layer on the surface of the copper pad protrudes outward to form a circle of positioning flange.

5. A semiconductor refrigeration plate welding structure according to claim 4, characterized in that: The end surface of the thermoelectric semiconductor particle is placed within the range surrounded by the positioning flange and can be moved to any position, and the end surface of the thermoelectric semiconductor particle always completely covers the tin filling groove.

6. The semiconductor refrigeration plate welding structure according to claim 1 is characterized in that: The opposite surfaces of the two substrates are both provided with sinking grooves, the sinking grooves are arranged correspondingly to the copper pads, and the copper pads are embedded in the sinking grooves.

7. A semiconductor refrigeration plate welding structure according to any one of claims 1 to 6, characterized in that: A circuit selection groove is arranged on the surface of the substrate opposite to the thermoelectric semiconductor particles. A circuit selection groove is arranged between two adjacent front and rear copper pads and between two adjacent left and right copper pads. The circuit selection groove is vacant or circuit solder is filled in the vacant circuit selection groove to realize the disconnection or conduction of adjacent copper pads.

8. A semiconductor refrigeration plate welding method, characterized in that: The welding of the semiconductor refrigeration plate welding structure described in any one of claims 1 to 7 comprises the following steps: S1, processing a plurality of sinking grooves and circuit selection grooves on a substrate; S2, installing a copper soldering pad in the sinking groove; S3, filling the tin filling groove on the copper soldering pad with assembly solder; S4, placing thermoelectric semiconductor particles at corresponding positions on the substrate; S5, heating the assembled substrate and thermoelectric semiconductor particles together, and connecting the thermoelectric semiconductor particles and the substrate together through assembly solder after cooling.

9. A semiconductor cooling plate welding method according to claim 8, characterized in that: In the S3 process, loop solder is filled in the loop selection groove between two copper pads that need to be connected to each other.

10. A semiconductor cooling plate welding method according to claim 8, characterized in that: After S5, the loop solder is filled in the loop selection groove between the two copper pads that need to be connected to each other.

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