CN-122028639-A - Anisotropic heat conduction filling type thermoelectric refrigeration device and manufacturing method thereof

CN122028639ACN 122028639 ACN122028639 ACN 122028639ACN-122028639-A

Abstract

The invention provides an anisotropic heat conduction filling type thermoelectric refrigeration device and a manufacturing method thereof, belonging to the technical field of thermoelectric refrigeration devices, comprising the following steps of preparing anisotropic heat conduction slurry, wherein the anisotropic heat conduction slurry comprises a high polymer resin matrix, hexagonal boron nitride and a dispersing agent; the method comprises the steps of carrying out pretreatment on the whole device, filling anisotropic heat conduction slurry into a gap in a vacuum environment, placing a thermoelectric refrigerator filled with the slurry on a rotary heating table in the center of a magnetic field generating device, applying a constant horizontal magnetic field, enabling the rotary heating table to rotate at a constant speed, carrying out in-situ heating and curing on the device under the state of keeping the magnetic field and the rotation, removing a protective film on the outer surface of the device, cleaning glue overflowing around the device, and carrying out secondary post-curing treatment on the device. The invention utilizes electromagnetic field to construct directional heat transfer path with high horizontal heat conduction and high vertical heat insulation, and improves thermal property while providing stable mechanical support and protection.

Inventors

XU JIANMING
CAO YUHAO
MOU YUN
LIU RUIJIE
HUANG YIQIAN
CHEN SIYU

Assignees

中山大学

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1. The manufacturing method of the anisotropic heat conduction filling type thermoelectric refrigeration device is characterized by comprising the following steps of: Preparing anisotropic heat conduction slurry, wherein the anisotropic heat conduction slurry comprises a high polymer resin matrix, hexagonal boron nitride and a dispersing agent; Selecting a thermoelectric refrigerator with welded parts, cleaning and surface activating the whole device, and then performing film-sticking protection on the outer surface of the ceramic substrate; Filling the anisotropic heat-conducting slurry into gaps between the ceramic substrates and the heat-conducting arms at two sides of the thermoelectric refrigerator in a vacuum environment, placing the thermoelectric refrigerator filled with the slurry on a rotary heating table at the center of a magnetic field generating device, applying a constant horizontal magnetic field, and simultaneously enabling the rotary heating table to rotate at a constant speed; And removing the protective film on the outer surface of the device and cleaning the glue overflow around the device after the in-situ heating and curing are completed, and then carrying out secondary post-curing treatment on the device.
2. The method of manufacturing an anisotropic conductive filled thermoelectric refrigeration device of claim 1 wherein the anisotropic conductive paste has an initial viscosity of 2000-5000 mPa s.
3. The method for manufacturing an anisotropic heat-conducting filled thermoelectric refrigeration device according to claim 1, wherein in the anisotropic heat-conducting paste, the polymer resin matrix is alicyclic epoxy resin or addition type liquid silicone rubber, the viscosity of the polymer resin matrix is 100-mPa.s, and the mass percentage of the hexagonal boron nitride is 30-55%.
4. The method of manufacturing an anisotropic heat conductive filled thermoelectric refrigeration device according to claim 1, wherein the hexagonal boron nitride has a ratio of diameter to thickness of 30-100 and an average sheet diameter of 10-50 μm, and/or the anisotropic heat conductive paste further contains a negative thermal expansion powder.
5. The method of manufacturing an anisotropic heat conductive filled thermoelectric refrigeration device as set forth in claim 1 wherein a silane coupling agent modified layer having a thickness of 0.5 to 5 μm is coated on the side wall of the heat conductive arm before filling the anisotropic heat conductive paste, and the modified layer is chemically bonded to the polymer resin matrix.
6. The method for manufacturing an anisotropic heat conductive filled thermoelectric refrigeration device according to claim 1, wherein the strength B of the horizontal magnetic field and the viscosity eta of the anisotropic heat conductive paste satisfy the following relationship that B2/eta is not less than 10T 2 /(Pa.s).
7. The method of fabricating an anisotropic conductive filled thermoelectric refrigeration device of claim 1 wherein said post-curing employs a gradient temperature post-curing process.
8. The method for manufacturing an anisotropic heat-conducting filling type thermoelectric refrigeration device according to claim 1, wherein the surface activation treatment is performed by cleaning with argon plasma, and the treatment time is 60-120s.
9. The method for manufacturing an anisotropic heat conductive filled thermoelectric refrigeration device as set forth in any one of claims 1 to 4 and 6 to 8 further comprising the step of plating a parylene film on the surface of said heat conductive arm by a vacuum vapor deposition method after said surface activation treatment.
10. An anisotropic heat conduction filling type thermoelectric refrigeration device is characterized by being manufactured by adopting the manufacturing method of any one of claims 1-9, and comprises two sides of ceramic substrates, a P-type heat conduction arm and an N-type heat conduction arm which are connected between the two sides of the ceramic substrates, a radiator connected with the ceramic substrates at the hot end, and anisotropic heat conduction slurry filled in gaps between the two sides of the ceramic substrates and the P-type heat conduction arm and the N-type heat conduction arm, wherein the anisotropic heat conduction slurry comprises a polymer resin matrix, hexagonal boron nitride and a dispersing agent.

Description

Anisotropic heat conduction filling type thermoelectric refrigeration device and manufacturing method thereof Technical Field The invention belongs to the technical field of thermoelectric refrigeration devices, and particularly relates to an anisotropic heat conduction filling type thermoelectric refrigeration device and a manufacturing method thereof. Background With the rapid development of modern microelectronic technology, optoelectronic technology and aerospace field, the thermal management problem of high power density electronic components is increasingly prominent due to the continuous improvement of the integration level of devices. The semiconductor thermoelectric refrigerator (Thermoelectric Cooler, TEC) is used as a solid-state refrigeration device for directly converting electric energy and heat energy by utilizing the Peltier effect (PELTIER EFFECT), and is an irreplaceable key thermal management component in the fields of a 5G optical module, a high-power laser diode, an infrared detector, a biomedical chip and the like by virtue of the unique advantages of no moving part, no noise, small volume, high temperature control precision (up to +/-0.01 ℃) and the like, and being capable of realizing local accurate cooling. In the above application scenario, the TEC device needs to have not only extremely high thermoelectric conversion efficiency, but also must be able to withstand severe mechanical environment and long-term thermal cycling impact. The core structure of a TEC typically consists of upper and lower ceramic substrates and P-type and N-type semiconductor thermally conductive arms (typically bismuth telluride based materials) sandwiched therebetween. When current passes, heat is pumped from the cold end ceramic substrate to the hot end ceramic substrate, thereby achieving refrigeration. However, as device dimensions are miniaturized and power densities increase, heat flux density per unit area increases dramatically, which presents unprecedented challenges to the thermal conduction mechanism inside TECs. Traditional heat dissipation designs tend to focus on external heat sinks, neglecting the thermal and mechanical behavior of the internal packaging structure of the TEC device. In addition, TEC devices face extremely complex multi-physical field coupling environments during actual service. On one hand, the huge temperature difference between the cold and hot ends can generate remarkable thermal expansion mismatch between the ceramic substrate and the heat conducting arm, so that huge shearing thermal stress is caused, and on the other hand, the thermoelectric material belongs to a brittle material and has extremely weak mechanical impact resistance. Under the frequent application scene of vibrations such as on-vehicle radar, mobile terminal, unprotected TEC very easily takes place heat conduction arm fracture or solder joint and peels off the inefficacy. Therefore, how to cooperatively optimize the thermal performance (refrigeration efficiency and soaking capability) and mechanical performance (structural strength and reliability) of the TEC has become a common key problem to be overcome in the field of the current thermoelectric technology. The current thermoelectric cooler field has the problem that high mechanical strength, excellent horizontal heat dissipation capability and extremely low vertical parasitic heat conduction cannot be achieved at the same time. The conventional filling scheme inevitably causes thermal resistance reduction in the vertical direction, thermal short circuit and refrigeration efficiency sacrifice if the heat-conducting glue is filled with high mechanical strength, and cannot solve the problem of thermal stress concentration caused by local hot spots if an air medium or low heat-conducting glue is adopted for maintaining the refrigeration efficiency. With the development of the TEC device towards miniaturization and high heat flux density, local hot spots become main reasons for early failure of the device, and the requirement cannot be met only by virtue of substrate heat dissipation. Therefore, there is an urgent need for a new filling structure that can effectively regulate the direction of heat flow, i.e. "good conductors" in the horizontal direction to eliminate hot spots, and "insulators" in the vertical direction to prevent thermal shorts, while also providing adequate mechanical support. Disclosure of Invention Aiming at the technical problems that the mechanical strength and the refrigeration efficiency are difficult to be compatible in the existing thermoelectric refrigerator packaging technology, and the vertical thermal short circuit and the internal hot spot accumulation are caused by the conventional filling material, the invention aims to provide an anisotropic heat conduction filling type thermoelectric refrigeration device and a manufacturing method thereof, so that the technical bottleneck that the thermal performance and the mechanical per