Thermoelectric refrigerating unit with mixed single-stage and multi-stage structure and manufacturing method of thermoelectric refrigerating unit

Abstract

The invention discloses a thermoelectric refrigerating unit with a mixed single-stage and multi-stage structure and a manufacturing method of the thermoelectric refrigerating unit, relates to the technical field of thermoelectric refrigerating units, and aims to solve the problem that an existing thermoelectric refrigerating unit cannot process uneven heat flux density. The thermoelectric refrigerating unit comprises substrates arranged on the two sides and a mixed refrigerating structure arranged between the substrates on the two sides, the mixed refrigerating structure comprises a multi-stage refrigerating area arranged in the center area and a single-stage refrigerating area around the multi-stage refrigerating area, and the multi-stage refrigerating area comprises a plurality of layers of multi-stage structure semiconductor particles. The single-stage refrigeration area comprises single-stage structure semiconductor particles, and the height of the single-stage structure semiconductor particles is flush with the height of the multi-stage refrigeration area; the invention further discloses a corresponding manufacturing method. According to the invention, high-intensity cooling of local hot spots and uniform temperature control of the whole base surface can be realized on the same device.

Description

A thermoelectric cooler with a hybrid single-stage and multi-stage structure and its manufacturing method. Technical Field

[0001] This invention relates to the field of thermoelectric cooler technology, specifically to a thermoelectric cooler with a hybrid single-stage and multi-stage structure and its manufacturing method. Background Technology

[0002] With the expansion of thermoelectric technology applications, thermoelectric coolers are now found in everything from everyday household appliances to aerospace. Typically, the shape of the device to be cooled is not perfectly regular, and the heat distribution is difficult to achieve perfectly uniformity. In some optical applications, most of the heat is concentrated in localized areas with extremely high heat flux and temperature. Conversely, the area around the base receives less heat, resulting in lower heat flux and temperature. During operation, the base's working surface experiences highly uneven temperature distribution, leading to localized overheating, thermal stress, and thermal gradients. This can cause laser wavelength drift, unstable output power, increased noise, modulator operating point shift, and performance degradation of passive devices. Simultaneously, thermal stress accelerates material aging, leading to solder joint cracking, chip damage, significantly shortening device lifespan, and reducing system stability and reliability.

[0003] For example, Chinese patent CN109950390A discloses a multi-stage thermoelectric cooler structure and its fabrication method. This thermoelectric cooler includes: multiple ceramic substrates, multiple layers of thermoelectric particles, and solder connecting the ceramic substrates and thermoelectric particles together. The ceramic substrates are direct plated ceramic substrates (DPC), and the solder is a copper-tin alloy solder. The stages of the multi-stage thermoelectric cooler are electrically interconnected using vertical through-holes. However, this still fails to solve the problem of uniform heat dissipation. Summary of the Invention

[0004] This invention solves the problem that existing thermoelectric coolers cannot handle uneven heat flux density. It proposes a thermoelectric cooler with a hybrid single-stage and multi-stage structure and its manufacturing method, which achieves high-intensity cooling of local hot spots and uniform temperature control of the entire base surface on the same device.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a thermoelectric cooler with a hybrid single-stage and multi-stage structure, comprising substrates disposed on both sides and a hybrid cooling structure disposed between the two substrates, wherein the hybrid cooling structure comprises a multi-stage cooling region disposed in the central region and single-stage cooling regions surrounding the multi-stage cooling region, wherein the multi-stage cooling region comprises several layers of multi-stage structured semiconductor particles, and the single-stage cooling region comprises single-stage structured semiconductor particles, wherein the height of the single-stage structured semiconductor particles is flush with the height of the multi-stage cooling region.

[0006] The present invention discloses a thermoelectric cooler with a hybrid single-stage and multi-stage structure, which integrates a hybrid cooling structure including a multi-stage cooling region and a single-stage cooling region. The multi-stage cooling region is located at the center of the device and directly below the target temperature control device. The single-stage cooling region is located around the multi-stage cooling region. Its cold end face and the cold end face of the multi-stage cooling region are kept at the same height plane through a common substrate, forming a continuous but non-uniform composite cooling surface.

[0007] The present invention is further configured such that: the substrate includes a common cold-end cooling substrate and a common hot-end heat dissipation substrate, the common cold-end cooling substrate is connected to the cold ends of the multi-stage cooling region and the single-stage cooling region respectively, and the common hot-end heat dissipation substrate is connected to the hot ends of the multi-stage cooling region and the single-stage cooling region respectively.

[0008] In this technical solution, the common cold end cooling substrate is located at the top, and the common hot end heat dissipation substrate is located at the bottom.

[0009] The present invention is further configured such that: the multi-level structure semiconductor particles are formed by stacking multiple PN junctions in series, and the single-level structure semiconductor particles are formed by connecting and linking a single PN junction in series.

[0010] In this technical solution, the multi-stage cooling zone is composed of two or three PN junctions stacked in series, which, after being powered on, forms the maximum cooling temperature difference to suppress the high temperature generated by the heat source.

[0011] The present invention is further configured such that: the multi-level structure semiconductor particles include a first layer of multi-level structure semiconductor particles and a second layer of multi-level structure semiconductor particles, and a high power density intermediate substrate is disposed between the first layer of multi-level structure semiconductor particles and the second layer of multi-level structure semiconductor particles; the multi-level cooling region is formed by stacking two-layer PN junctions in series through the high power density intermediate substrate.

[0012] The present invention is further configured such that the thermocouple grains of the multi-stage refrigeration region and the single-stage refrigeration region are made of thermoelectric materials with the same composition.

[0013] In this technical solution, the thermocouple grains in both the stage-cooling region and the single-stage cooling region are based on Bi2Te3.

[0014] The present invention is further configured such that the thermocouple grains of the multi-stage cooling region and the single-stage cooling region are selected with different thermoelectric materials according to their operating temperature range.

[0015] The present invention is further configured such that the ratio of the number of PN junction pairs in the single-stage refrigeration region to the number of PN junction pairs in the multi-stage refrigeration region is in the range of 3:1 to 10:1.

[0016] In this technical solution, the above-described settings ensure a balance between homogenization and localized cooling capabilities.

[0017] The present invention is further configured such that: the multi-stage cooling region is respectively connected to a multi-stage negative electrode wire and a multi-stage positive electrode wire, the single-stage cooling region is respectively connected to a single-layer positive electrode wire and a single-layer negative electrode wire, and the multi-stage cooling region and the single-stage cooling region are connected to an external driving circuit through wires.

[0018] In this technical solution, the external drive circuit can control multi-stage and single-stage structures individually to regulate the temperature difference of the cold surface more evenly, or the entire circuit can be connected in series or parallel for convenient control.

[0019] The present invention is further configured such that the substrate is made of aluminum nitride or aluminum oxide material with high thermal conductivity.

[0020] A method for manufacturing a thermoelectric cooler with a hybrid single-stage and multi-stage structure, applicable to the aforementioned thermoelectric cooler with a hybrid single-stage and multi-stage structure, includes the following steps: S1, fixing a common heat dissipation substrate, fabricating a first layer of multi-stage P-type particles and a first layer of multi-stage N-type particles using a grid sheet, and covering it with a high power density intermediate substrate; S2, fabricating a second layer of multi-stage P-type particles and a second layer of multi-stage N-type particles using a grid sheet; S3, fabricating a single-stage P-type particle and a single-stage N-type particle using a grid sheet, and covering it with a common cold-end cooling substrate; S4, heating and cleaning in a vacuum furnace, and welding single-stage and multi-stage structure wires.

[0021] Regarding the above manufacturing method, before fixing the common heat dissipation substrate, the following process is also included: a synchronous sintering process for PN junctions of different heights is pre-set, the substrates are assembled from the inside out, and solder paste is printed on all substrates by screen printing.

[0022] The present invention provides a thermoelectric cooler with a hybrid single-stage and multi-stage structure, which brings the following technical effects: 1. It precisely targets the cooling capacity to the most needed area, avoiding the ultra-high power consumption caused by using a multi-stage structure globally, and significantly improving the energy efficiency ratio; 2. The single-stage area acts as a thermal homogenizer, effectively eliminating the huge temperature gradient that may occur at the edges of the multi-stage area, greatly improving the overall temperature distribution uniformity of the optical device substrate; 3. The integrated design reduces the package volume and internal connection interface, reduces contact thermal resistance and the risk of failure due to mismatch in thermal expansion coefficients, and improves the mechanical reliability and lifespan of the device; 4. The dual-zone independent power supply design allows for real-time adjustment of the cooling strategy according to changes in thermal load, resulting in a high degree of intelligence. Attached Figure Description

[0023] Figure 1 is an exploded view of a thermoelectric cooler with a hybrid single-stage and multi-stage structure according to the present invention.

[0024] Figure 2 is an overall schematic diagram of a thermoelectric cooler with a hybrid single-stage and multi-stage structure according to the present invention.

[0025] Figure 3 is a cross-sectional view of a thermoelectric cooler with a hybrid single-stage and multi-stage structure according to the present invention, with respect to AA.

[0026] Figure 4 is an internal schematic diagram of a thermoelectric cooler with a hybrid single-stage and multi-stage structure according to the present invention.

[0027] Figure 5 is a flowchart of a method for manufacturing a thermoelectric cooler with a hybrid single-stage and multi-stage structure according to the present invention.

[0028] The attached figures are labeled as follows: 1. Common cold end cooling substrate; 2. Second layer multi-level structure semiconductor particle; 3. High power density intermediate substrate; 4. First layer multi-level structure semiconductor particle; 5. Single-level structure semiconductor particle; 6. Common hot end heat dissipation substrate; 7. Single-layer structure positive electrode wire; 8. Multi-level structure positive electrode wire; 9. Multi-level structure negative electrode wire; 10. Single-layer structure negative electrode wire. Detailed Implementation

[0029] Example 1: To address the problem that existing thermoelectric coolers cannot handle uneven heat flux density, this example proposes a thermoelectric cooler with a hybrid single-stage and multi-stage structure. Referring to Figures 1 to 4, it includes substrates on both sides and a hybrid cooling structure in the middle of the two substrates. The hybrid cooling structure includes a multi-stage cooling region and a single-stage cooling region. The multi-stage cooling region is located in the central region, and the single-stage cooling region is located around the multi-stage cooling region. The multi-stage cooling region mainly includes several layers of multi-stage semiconductor particles, and the single-stage cooling region includes single-stage semiconductor particles 5. The height of the single-stage semiconductor particles 5 is aligned with the height of the multi-stage cooling region.

[0030] The present invention discloses a thermoelectric cooler with a hybrid single-stage and multi-stage structure. The hybrid cooling structure includes a multi-stage cooling region and a single-stage cooling region. The multi-stage cooling region is located at the center of the device and directly below the target temperature control device. The single-stage cooling region is located around the multi-stage cooling region. Its cold end face and the cold end face of the multi-stage cooling region are kept at the same height plane through a common substrate, forming a continuous but non-uniform composite cooling surface. The function of the single-stage cooling region is to assist in heat dissipation and minimize the temperature difference of the entire cold surface.

[0031] Referring to Figures 1, 2 and 3, the aforementioned substrate mainly includes a common cold-end cooling substrate 1 and a common hot-end heat dissipation substrate 6. The common cold-end cooling substrate 1 is connected to the cold ends of the multi-stage cooling region and the single-stage cooling region, respectively, and the common hot-end heat dissipation substrate 6 is connected to the hot ends of the multi-stage cooling region and the single-stage cooling region, respectively.

[0032] Multilevel semiconductor particles are formed by stacking multiple PN junctions in series, while single-level semiconductor particles are formed by connecting and linking single-layer PN junctions in series.

[0033] In this technical solution, the multi-stage cooling region is composed of two or three PN junctions stacked in series, which, when energized, creates the maximum cooling temperature difference to suppress the high temperature generated by the heat source. The single-stage cooling region consists of a single PN junction connected in series, with the particle height level with that of the multi-stage region.

[0034] Referring to Figures 2, 3 and 4, the multi-level structure semiconductor particles mainly include a first-layer multi-level structure semiconductor 4 and a second-layer multi-level structure semiconductor particle 2. A high-power-density intermediate substrate 3 is also provided between the second-layer multi-level structure semiconductor particle 2 and the first-layer multi-level structure semiconductor particle 4. The multi-level cooling region is formed by stacking double-layer PN junctions in series through the high-power-density intermediate substrate 3.

[0035] In this embodiment, the thermocouple grains in the multi-stage cooling region and the single-stage cooling region use thermoelectric materials with the same composition. For example, Bi2Te3-based materials can be used in both.

[0036] The ratio of the number of PN junction pairs in a single-stage cooling region to that in a multi-stage cooling region is controlled between 3:1 and 10:1 to ensure a balance between homogenization capability and local cooling capability.

[0037] Referring to Figures 1, 2, and 4, the multi-stage cooling region is connected to the multi-stage negative electrode wire 9 and the multi-stage positive electrode wire 8, respectively, and the single-stage cooling region is connected to the single-layer positive electrode wire 7 and the single-layer negative electrode wire 10, respectively. The multi-stage cooling region and the single-stage cooling region are connected to the external driving circuit through wires.

[0038] In this technical solution, the external drive circuit can control multi-stage and single-stage structures individually to regulate the temperature difference of the cold surface more evenly, or the entire circuit can be connected in series or parallel for convenient control.

[0039] In this embodiment, the common cold end cooling substrate 1 and the common hot end heat dissipation substrate 6 are made of aluminum nitride or aluminum oxide materials with high thermal conductivity.

[0040] In this embodiment, the spacing between the guide vanes in the multi-stage cooling zone is made as small as possible to improve power density and enable it to carry the maximum heat transfer. The surrounding single-stage cooling zones can be set as needed, and there is no requirement for high-density arrangement.

[0041] In this embodiment, the multi-stage cooling zone and the single-stage cooling zone can be connected in series / parallel for power supply or controlled separately for power supply. If more flexible control of temperature uniformity is required, the input current of the two zones can be adjusted independently to achieve dynamic and adaptive fine thermal management. If the control system is limited and can only connect one set of control circuits, the single-stage loop particles can be matched according to the multi-stage loop ratio.

[0042] In this embodiment, the temperature difference during forced cooling in the multi-stage refrigeration structure is wider than that in the single-stage refrigeration structure, ranging from 20 to 30°C. The two structures can be coordinated according to actual working conditions, allowing for greater adjustment flexibility.

[0043] This embodiment proposes a thermoelectric cooler with a hybrid single-stage and multi-stage structure, which can achieve high-intensity cooling of local hot spots and uniform temperature control of the entire base surface on the same device. Existing conventional thermoelectric coolers have uniformly arranged particles, which makes it impossible to handle the problem of uneven heat flux density. Even with the addition of a heat spreader, it is difficult to achieve the desired effect. A common method is to change the local particle density, but due to the extreme temperature difference of a single layer of particles, it is impossible to form a larger temperature difference to suppress heat in areas with high heat flux density. This invention introduces the concept of multi-stage hybrid arrangement and adopts a hybrid structure thermoelectric cooler, which integrates a single-layer and multi-layer hybrid cooling structure and includes the following components: a common hot end heat dissipation substrate 6, a common cold end cooling substrate 1, a high power density intermediate substrate 3, single-stage semiconductor particles 5, a first layer of multi-stage semiconductor particles 4, a second layer of multi-stage semiconductor particles 2, and single-layer and multi-stage conductive wires.

[0044] The beneficial effects of the technical solution in this embodiment are reflected in the following aspects.

[0045] 1. High efficiency and low power consumption: The cooling capacity is "precisely deployed" to the areas that need it most, avoiding the ultra-high power consumption caused by using a multi-level structure globally, and the energy efficiency ratio is significantly improved.

[0046] 2. Excellent temperature uniformity: The single-level region acts as a "thermal homogenizer," effectively eliminating the huge temperature gradients that may occur at the edges of multi-level regions, and greatly improving the overall temperature distribution uniformity of the optical device substrate.

[0047] 3. Compact structure and high reliability: The integrated design reduces the package size and internal connection interface, reduces contact thermal resistance and the risk of failure due to mismatch of thermal expansion coefficients, and improves the mechanical reliability and lifespan of the device.

[0048] 4. Dynamic controllability: The dual-zone independent power supply design allows for real-time adjustment of cooling strategies based on changes in thermal load, resulting in a high degree of intelligence.

[0049] Example 2 This example proposes a thermoelectric cooler with a hybrid single-stage and multi-stage structure, including substrates on both sides and a hybrid cooling structure in the middle of the two substrates. The hybrid cooling structure includes a multi-stage cooling region and a single-stage cooling region. The multi-stage cooling region is located in the central region, and the single-stage cooling region is located around the multi-stage cooling region. The multi-stage cooling region mainly includes several layers of multi-stage structure semiconductor particles, and the single-stage cooling region includes single-stage structure semiconductor particles 5. The height of the single-stage structure semiconductor particles 5 is aligned with the height of the multi-stage cooling region.

[0050] The present invention discloses a thermoelectric cooler with a hybrid single-stage and multi-stage structure. The hybrid cooling structure includes a multi-stage cooling region and a single-stage cooling region. The multi-stage cooling region is located at the center of the device and directly below the target temperature control device. The single-stage cooling region is located around the multi-stage cooling region. Its cold end face and the cold end face of the multi-stage cooling region are kept at the same height plane through a common substrate, forming a continuous but non-uniform composite cooling surface. The function of the single-stage cooling region is to assist in heat dissipation and minimize the temperature difference of the entire cold surface.

[0051] The difference from Example 1 is that in this example, the thermocouple grains of the multi-stage cooling region and the single-stage cooling region are selected with different thermoelectric materials according to their operating temperature range, in order to further improve the overall performance. For example, the first layer of multi-stage structure semiconductor particles 4 in the multi-stage cooling region uses Bi2Te3, and the second layer of multi-stage structure semiconductor particles 2 uses SbTe-based materials.

[0052] Example 3 This example proposes a thermoelectric cooler with a hybrid single-stage and multi-stage structure. Referring to Figures 1 to 4, it includes substrates disposed on both sides and a hybrid cooling structure disposed between the two substrates. The hybrid cooling structure includes a multi-stage cooling region and a single-stage cooling region. The multi-stage cooling region is disposed in the central region, and the single-stage cooling region is disposed around the multi-stage cooling region. The multi-stage cooling region mainly includes several layers of multi-stage structure semiconductor particles, and the single-stage cooling region includes single-stage structure semiconductor particles 5. The height of the single-stage structure semiconductor particles 5 is aligned with the height of the multi-stage cooling region.

[0053] Referring to Figures 1, 2 and 3, the aforementioned substrate mainly includes a common cold-end cooling substrate 1 and a common hot-end heat dissipation substrate 6. The common cold-end cooling substrate 1 is connected to the cold ends of the multi-stage cooling region and the single-stage cooling region, respectively, and the common hot-end heat dissipation substrate 6 is connected to the hot ends of the multi-stage cooling region and the single-stage cooling region, respectively.

[0054] Multilevel semiconductor particles are formed by stacking multiple PN junctions in series, while single-level semiconductor particles are formed by connecting and linking single-layer PN junctions in series.

[0055] In this technical solution, the multi-stage cooling region is composed of two or three PN junctions stacked in series, which, when energized, creates the maximum cooling temperature difference to suppress the high temperature generated by the heat source. The single-stage cooling region consists of a single PN junction connected in series, with the particle height level with that of the multi-stage region.

[0056] Referring to Figures 2, 3 and 4, the multi-level structure semiconductor particles mainly include a first-layer multi-level structure semiconductor 4 and a second-layer multi-level structure semiconductor particle 2. A high-power-density intermediate substrate 3 is also provided between the second-layer multi-level structure semiconductor particle 2 and the first-layer multi-level structure semiconductor particle 4. The multi-level cooling region is formed by stacking double-layer PN junctions in series through the high-power-density intermediate substrate 3.

[0057] In this embodiment, the thermocouple grains in the multi-stage cooling region and the single-stage cooling region use thermoelectric materials with the same composition. For example, Bi2Te3-based materials can be used in both.

[0058] The ratio of the number of PN junction pairs in a single-stage cooling region to that in a multi-stage cooling region is controlled between 3:1 and 10:1 to ensure a balance between homogenization capability and local cooling capability.

[0059] Referring to Figures 1, 2, and 4, the multi-stage cooling region is connected to the multi-stage negative electrode wire 9 and the multi-stage positive electrode wire 8, respectively, and the single-stage cooling region is connected to the single-layer positive electrode wire 7 and the single-layer negative electrode wire 10, respectively. The multi-stage cooling region and the single-stage cooling region are connected to the external driving circuit through wires.

[0060] In this technical solution, the external drive circuit can control multi-stage and single-stage structures individually to regulate the temperature difference of the cold surface more evenly, or the entire circuit can be connected in series or parallel for convenient control.

[0061] In this embodiment, the common cold end cooling substrate 1 and the common hot end heat dissipation substrate 6 are made of aluminum nitride or aluminum oxide materials with high thermal conductivity.

[0062] In this embodiment, the spacing between the guide vanes in the multi-stage cooling zone is made as small as possible to improve power density and enable it to carry the maximum heat transfer. The surrounding single-stage cooling zones can be set as needed, and there is no requirement for high-density arrangement.

[0063] In this embodiment, the multi-stage cooling zone and the single-stage cooling zone can be connected in series / parallel for power supply or controlled separately for power supply. If more flexible control of temperature uniformity is required, the input current of the two zones can be adjusted independently to achieve dynamic and adaptive fine thermal management. If the control system is limited and can only connect one set of control circuits, the single-stage loop particles can be matched according to the multi-stage loop ratio.

[0064] In this embodiment, the temperature difference during forced cooling in the multi-stage refrigeration structure is wider than that in the single-stage refrigeration structure, ranging from 20 to 30°C. The two structures can be coordinated according to actual working conditions, allowing for greater adjustment flexibility.

[0065] This embodiment proposes a thermoelectric cooler with a hybrid single-stage and multi-stage structure, which can achieve high-intensity cooling of local hot spots and uniform temperature control of the entire base surface on the same device. Existing conventional thermoelectric coolers have uniformly arranged particles, which makes it impossible to handle the problem of uneven heat flux density. Even with the addition of a heat spreader, it is difficult to achieve the desired effect. A common method is to change the local particle density, but due to the extreme temperature difference of a single layer of particles, it is impossible to form a larger temperature difference to suppress heat in areas with high heat flux density. This invention introduces the concept of multi-stage hybrid arrangement and adopts a hybrid structure thermoelectric cooler, which integrates a single-layer and multi-layer hybrid cooling structure and includes the following components: a common hot end heat dissipation substrate 6, a common cold end cooling substrate 1, a high power density intermediate substrate 3, single-stage semiconductor particles 5, a first layer of multi-stage semiconductor particles 4, a second layer of multi-stage semiconductor particles 2, and single-layer and multi-stage conductive wires.

[0066] This embodiment describes the present invention in further detail through a preferred embodiment and in conjunction with the accompanying drawings. Referring to Figure 1, the thermoelectric cooler consists of, from top to bottom, a common cold end cooling substrate 1, a second layer of multi-level structure semiconductor particles 2, a high power density intermediate substrate 3, a first layer of multi-level structure semiconductor particles 4, a single-level structure semiconductor particles 5, and a common hot end heat dissipation substrate 6.

[0067] In this embodiment, the hybrid cooling structure includes a two-stage cooling region at the center and a single-stage cooling region surrounding it. The two-stage cooling region is formed by stacking double-layer PN junction thermoelectric materials in series through a high-power-density intermediate substrate 3. The single-stage cooling region is formed by connecting conventional single-layer PN junctions in series through a common cold-end cooling substrate 1 and a common hot-end heat dissipation substrate 6.

[0068] The common cold-end cooling substrate 1 connects the cold ends of the two regions into a unified mounting plane. The common hot-end heat dissipation substrate 6 provides a unified heat dissipation path for all PN junctions.

[0069] The two-stage cooling zone and the single-stage cooling zone are connected by a single-layer positive conductor 7, a multi-stage positive conductor 8, a multi-stage negative conductor 9, and a single-layer negative conductor 10, respectively, and can be connected to an external drive circuit for independent control.

[0070] Example 4 is based on Example 1. This example also proposes a method for manufacturing a thermoelectric cooler with a hybrid single-stage and multi-stage structure. Referring to Figure 5, it includes the following steps.

[0071] Step S1: Fix the common heat dissipation substrate. Then, use a grid sheet to create a first layer of multi-level structure P-type particles and a first layer of multi-level structure N-type particles. Finally, cover with a high power density intermediate substrate.

[0072] After screen printing solder paste onto all the substrates, first fix the common heat dissipation substrate on the base, insert the first layer of multi-level structure P-type particle grid sheet, pour in the particles, gently shake the mold left and right until the particles fill the grooves, then pour out the excess particles and remove the grid sheet; insert the first layer of multi-level structure N-type particle grid sheet, pour in the particles, gently shake the mold left and right until the particles fill the grooves, then pour out the excess particles and remove the grid sheet; then, cover with the high power density intermediate substrate and press down slightly.

[0073] Step S2: Use grid sheets to create P-type particles with a second layer of multi-level structure and N-type particles with a second layer of multi-level structure.

[0074] Specifically, insert the second layer of the multi-level structure P-type particle grid sheet, pour in the particles, gently shake the mold from side to side until the particles fill the grooves, then pour out the excess particles and remove the grid sheet; insert the second layer of the multi-level structure N-type particle grid sheet, pour in the particles, gently shake the mold from side to side until the particles fill the grooves, then pour out the excess particles and remove the grid sheet.

[0075] Step S3: Use grid sheets to create single-level P-type particles and single-level N-type particles, and cover them with a common cold end cooling substrate.

[0076] Specifically, insert a single-stage P-type particle grid sheet, pour in particles, and gently shake the mold from side to side until the grooves are filled. Then, pour out the excess particles and remove the grid sheet. Insert a single-stage N-type particle grid sheet, pour in particles, and gently shake the mold from side to side until the grooves are filled. Then, pour out the excess particles and remove the grid sheet. Cover with the common cold-end cooling substrate and press down slightly.

[0077] Step S4: Heat and clean in a vacuum furnace, then weld single-stage and multi-stage wires.

[0078] Specifically, after removing the entire thermoelectric cooler, it is placed in a vacuum furnace, a temperature profile is set, and after sintering, it is removed and placed in a solvent to clean the flux. Then, the module is placed on a heating platform, the heating temperature is set, and the wires are soldered using a soldering gun. First, single-stage wires are soldered, then multi-stage wires are soldered. Finally, the flux is cleaned again with a solvent, and the manufacturing process is complete.

Claims

1. A thermoelectric cooler with a hybrid single-stage and multi-stage structure, characterized in that, It includes substrates on both sides and a hybrid cooling structure in the middle of the two substrates. The hybrid cooling structure includes a multi-stage cooling region in the central region and a single-stage cooling region around the multi-stage cooling region. The multi-stage cooling region includes several layers of multi-stage semiconductor particles. The single-stage cooling region includes single-stage semiconductor particles (5). The height of the single-stage semiconductor particles (5) is flush with the height of the multi-stage cooling region.

2. A thermoelectric cooler with a hybrid single-stage and multi-stage structure according to claim 1, characterized in that, The substrate includes a common cold end cooling substrate (1) and a common hot end heat dissipation substrate (6). The common cold end cooling substrate (1) is connected to the cold ends of the multi-stage cooling region and the single-stage cooling region, respectively. The common hot end heat dissipation substrate (6) is connected to the hot ends of the multi-stage cooling region and the single-stage cooling region, respectively.

3. A thermoelectric cooler with a hybrid single-stage and multi-stage structure according to claim 1 or 2, characterized in that, The multi-level semiconductor particles are formed by stacking multiple PN junctions in series, and the single-level semiconductor particles (5) are formed by connecting and linking a single PN junction in series.

4. A thermoelectric cooler with a hybrid single-stage and multi-stage structure according to claim 3, characterized in that, The multi-level semiconductor particles include a first-level multi-level semiconductor particle (4) and a second-level multi-level semiconductor particle (2). A high-power-density intermediate substrate (3) is also provided between the first-level multi-level semiconductor particle (4) and the second-level multi-level semiconductor particle (2). The multi-level cooling region is formed by stacking two-layer PN junctions in series through the high-power-density intermediate substrate (3).

5. A thermoelectric cooler with a hybrid single-stage and multi-stage structure according to claim 1 or 2, characterized in that, The thermocouple grains in the multi-stage refrigeration region and the single-stage refrigeration region use thermoelectric materials with the same composition.

6. A thermoelectric cooler with a hybrid single-stage and multi-stage structure according to claim 1 or 2, characterized in that, The thermocouple grains in the multi-stage cooling region and the single-stage cooling region are selected with different thermoelectric materials according to their operating temperature range.

7. A thermoelectric cooler with a hybrid single-stage and multi-stage structure according to claim 1, 2, or 4, characterized in that, The ratio of the number of PN junction pairs in the single-stage cooling region to the number of PN junction pairs in the multi-stage cooling region ranges from 3:1 to 10:

1.

8. A thermoelectric cooler with a hybrid single-stage and multi-stage structure according to claim 3, characterized in that, The multi-stage cooling zones are respectively connected to multi-stage negative electrode wires (9) and multi-stage positive electrode wires (8), and the single-stage cooling zones are respectively connected to single-layer positive electrode wires (7) and single-layer negative electrode wires (10). The multi-stage cooling zones and the single-stage cooling zones are connected to an external driving circuit through wires.

9. A thermoelectric cooler with a hybrid single-stage and multi-stage structure according to claim 1 or 2, characterized in that, The substrate is made of aluminum nitride or aluminum oxide material with high thermal conductivity.

10. A method for manufacturing a thermoelectric cooler with a hybrid single-stage and multi-stage structure, applicable to the thermoelectric cooler with a hybrid single-stage and multi-stage structure as described in any one of claims 1 to 9, characterized in that, The process includes the following steps: S1, fixing a common heat dissipation substrate, using a grid sheet to create a first layer of multi-level structured P-type particles and a first layer of multi-level structured N-type particles, and covering it with a high power density intermediate substrate; S2, using a grid sheet to create a second layer of multi-level structured P-type particles and a second layer of multi-level structured N-type particles; S3, using a grid sheet to create a single-level structured P-type particles and a single-level structured N-type particles, and covering it with a common cold end cooling substrate; S4, heating and cleaning in a vacuum furnace, and welding single-level structured wires and multi-level structured wires.

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