Reversible adhesive flexible semiconductor refrigeration device and preparation method and application thereof

Abstract

The application discloses a reversible adhesion flexible semiconductor refrigeration device and a preparation method and application thereof, and belongs to the technical field of semiconductor refrigeration. The device comprises a pi-type thermoelectric pair interconnection array, a substrate layer, a connecting material and a reversible adhesion layer. The pi-type thermoelectric pair interconnection array comprises a packaging material, an interconnection electrode and N / P-type thermoelectric arms (arranged at intervals and connected in series in a thermal parallel structure by the interconnection electrode, and embedded in the packaging material in the upper half part), the bottom end of the pi-type thermoelectric pair interconnection array is embedded with the substrate layer, and the substrate layer is connected with the reversible adhesion layer through the connecting material (a phase change temperature control type). In the preparation, the pi-type thermoelectric pair interconnection array and the reversible adhesion substrate are prepared first, and then the device is obtained through bonding, filling of the substrate layer material and solidification. The device realizes efficient refrigeration and convenient disassembly by switching the interface adhesion through temperature control, overcomes the traditional defects, and is suitable for wearable electronics, miniature medical treatment and portable devices.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor refrigeration technology, and particularly relates to a reversibly adhesive flexible semiconductor refrigeration device, its preparation method, and its application. Background Technology

[0002] Flexible thermoelectric cooling devices rely on the Peltier effect of thermoelectric materials to achieve precise temperature control through an applied electric field. They also offer significant advantages such as being noiseless, vibration-free, and compact, perfectly meeting the core requirements of emerging fields like wearable electronics and micro-medical devices for flexible cooling technology. Traditional rigid thermoelectric modules are not only difficult to adapt to curved surfaces but also involve complex and cumbersome manufacturing processes. In contrast, flexible devices employ organic thermoelectric materials or inorganic / organic composite structures, retaining excellent thermoelectric performance while possessing good mechanical flexibility, effectively overcoming the shortcomings of traditional products.

[0003] With the rapid iteration of the Internet of Things (IoT) and portable devices, localized thermal management issues are becoming increasingly prominent. Developing efficient and low-cost flexible thermoelectric cooling technology has become crucial for addressing this pain point and is one of the core research hotspots in the field of energy materials. However, when thermoelectric cooling devices are operating, the high thermal resistance between the interfaces leads to a significant amount of heat loss at the contact interface between the device and the heat source. Existing solutions often use high thermal conductivity interface materials to fill the gaps to exclude air, or optimize the contact effect by increasing pressure and improving adhesive strength. However, these solutions have significant limitations: for scenarios requiring frequent device disassembly, such as human body cooling or mobile phone cooling back clips, high adhesive strength severely affects the ease of disassembly, while low adhesive strength increases contact thermal resistance, directly restricting cooling efficiency. Therefore, developing a flexible semiconductor device with adjustable adhesion between the device and the heat source, achieving both low interface thermal resistance and efficient cooling while ensuring easy disassembly, has become a pressing technical challenge in this field. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention proposes a reversibly adhesive flexible semiconductor cooling device, its fabrication method, and its applications.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A reversibly adhesive flexible semiconductor cooling device, comprising: a π-type thermocouple interconnect array, a substrate layer, a connecting material, and a reversible adhesive layer;

[0007] The π-type thermocouple interconnect array includes: encapsulation material, interconnect electrodes, and thermocouples; wherein, the thermocouples include N-type semiconductor thermocouple arms and P-type semiconductor thermocouple arms, which are arranged at intervals and interconnected at their top ends by interconnect electrodes to form π-type thermocouple interconnect units, and the bottom ends of two π-type thermocouple interconnect units are interconnected by interconnect electrodes to form a π-type thermal parallel and electrical series structure; the upper part of the thermocouple is embedded in the encapsulation material;

[0008] The bottom end of the π-type thermocouple interconnect array is embedded in the substrate layer;

[0009] The base layer is connected to the reversible adhesion layer via a connecting material.

[0010] This invention uses N-type and P-type semiconductor thermoelectric units to form thermoelectric pairs through thermal parallel and electrical series connections. These pairs are then encapsulated with a packaging material to serve as thermoelectric units, with flexible metal acting as connecting wires between the thermoelectric units. A flexible, temperature-controlled, reversible adhesive material serves as the interface material between the device and the heat source. A porous foam material and a highly thermally conductive substrate are used to connect and encapsulate the device with the reversible adhesive material.

[0011] The working principle of the reversible adhesive flexible semiconductor cooling device provided by this invention is as follows: During operation, when a direct current is applied to the thermoelectric cooling device, its cold end temperature decreases, causing the phase change material (hydrated salt) in the reversible adhesion layer to undergo a liquid-solid phase transition. During the phase transition, hydrogen bonds within the gel are released, forming a strong bond between the device and the heat source, effectively reducing interfacial contact thermal resistance and thus improving cooling efficiency. When it is necessary to disassemble the device, a solid-liquid phase transition is initiated in the phase change material (hydrated salt) in the reversible adhesion layer through temperature control. The release of water consumes the hydrogen bonds within the gel, significantly weakening the bond between the device and the heat source, thus enabling convenient disassembly.

[0012] Furthermore, the substrate layer is prepared from a matrix material and a reinforcing phase as raw materials;

[0013] The matrix material is selected from polyurethane, polydimethylsiloxane (PDMS) or biodegradable plastic (Ecoflex).

[0014] The reinforcing phase is selected from at least one of liquid metal, silver nanowires, copper nanoparticles, boron nitride, aluminum nitride, aluminum oxide, and graphene.

[0015] Furthermore, the connecting material is selected from nickel foam, titanium foam, or foam, with a thickness of 0.5-2 mm.

[0016] Furthermore, the reversible adhesion layer is a flexible temperature-controlled reversible adhesion material, including phase change temperature-controlled reversible adhesion materials.

[0017] Furthermore, the preparation method of the phase change temperature-controlled reversible adhesive material includes the following steps: mixing water, acrylamide, anhydrous sodium sulfate and borax and heating and stirring, adding oxidized carboxymethylated nanocellulose, stirring evenly and then adding catalyst and crosslinking agent, continuing to stir, adding thermal initiator, and obtaining phase change temperature-controlled reversible adhesive material.

[0018] Furthermore, the encapsulation material is prepared from a matrix material and fillers as raw materials;

[0019] The matrix material is selected from polyurethane, polydimethylsiloxane, or epoxy resin;

[0020] The filler is selected from silica microspheres (particle size 30-700μm), aerogel or vermiculite.

[0021] Furthermore, the interconnecting electrodes are made of conductive metal.

[0022] Furthermore, the thermoelectric pair material is selected from chalcogenide thermoelectric materials based on (Bi,Sb)2(Te,Se)3, MgAgSb, Mg3(Bi,Sb)2, Ag2Se, or SnSe, such as Bi2Te3, Sb2Te3, MgAgSb, MgBi, Mg3Sb2, or SnSe.

[0023] The present invention also provides a method for preparing the reversibly adhered flexible semiconductor cooling device, comprising the following steps:

[0024] The thermocouple material is placed between two sets of metal electrode plates, and the thermocouple is connected to the metal plates by hot pressing welding. Encapsulation material is poured in, cured, and cut to obtain a π-type thermocouple interconnection array.

[0025] The bonding material is placed in a square mold, the reversible adhesion layer material is poured in, and a polymerization reaction is carried out to obtain a reversible adhesion substrate.

[0026] A sil-Poxy™ adhesive is applied to the bottom of the π-type thermocouple interconnect array and adhered to the reversible adhesive substrate. A base layer material is then poured in and cured to obtain a reversibly adhesive flexible semiconductor cooling device.

[0027] The present invention also provides an application of the reversibly adhesive flexible semiconductor cooling device in wearable electronic devices, micro medical devices or portable devices.

[0028] Compared with the prior art, the present invention has the following advantages and technical effects:

[0029] This invention utilizes the built-in temperature control function of a semiconductor thermoelectric cooling device to achieve flexible switching of interfacial adhesion by adjusting the temperature-controlled reversible adhesive material between the device and the heat source. When the device is cooling the heat source, the reversible adhesive material exhibits high adhesive strength, effectively reducing interfacial contact thermal resistance and significantly improving cooling efficiency. When disassembly of the device is required, the temperature control function of the device reduces the adhesive strength of the reversible adhesive material, making the disassembly process convenient and efficient. This semiconductor thermoelectric cooling device has a simple and reasonable structure, successfully overcoming the shortcomings of existing technologies.

[0030] Compared to traditional methods that reduce interfacial thermal resistance by increasing the thermal conductivity of interfacial materials, this invention not only overcomes the shortcomings of traditional methods, such as limited improvement in cooling efficiency and poor wearability, but also has the advantages of being lightweight and flexible, significantly reducing thermal resistance, and having better portability and wearing comfort. In addition, it is low in cost and has a simple manufacturing process. Attached Figure Description

[0031] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0032] Figure 1 A cross-sectional schematic diagram of the reversibly adhesive flexible semiconductor cooling device provided by the present invention;

[0033] Figure 2 A 3D schematic diagram of the reversible adhesive flexible semiconductor cooling device provided by the present invention;

[0034] Figure 3 This is a physical image of the reversibly adhesive flexible semiconductor cooling device prepared in Example 1 of the present invention;

[0035] Figure 4 The image shows a comparison of the adhesion forces of the reversibly adhesive flexible semiconductor refrigeration device prepared in Example 1 at different temperatures and on different materials.

[0036] Figure 5 The results show the cooling performance of the samples prepared in Example 1 and Comparative Example 1 when applied to the human body;

[0037] Among them, 1-interconnect electrode, 2-thermoelectric pair, 3-encapsulation material, 4-connection material, 5-reversible adhesion layer, and 6-substrate layer. Detailed Implementation

[0038] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0039] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0040] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0041] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be obvious to those skilled in the art. This specification and embodiments are merely exemplary.

[0042] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0043] Figure 1 This is a cross-sectional schematic diagram of the reversibly adhesive flexible semiconductor cooling device prepared in Example 1 of the present invention. Figure 2 This is a 3D schematic diagram; the structure includes: a π-type thermocouple interconnect array, a substrate layer 6, a connecting material 4, and a reversible adhesion layer 5; the π-type thermocouple interconnect array includes: an encapsulation material 3, interconnect electrodes 1, and thermocouples 2; wherein, the thermocouple 2 includes N-type semiconductor thermocouple arms and P-type semiconductor thermocouple arms, which are arranged at intervals and interconnected at their top ends by interconnect electrodes 1 to obtain π-type thermocouple interconnect units, and the bottom ends of two π-type thermocouple interconnect units are interconnected by interconnect electrodes 1 to form a π-type thermal parallel and electrical series structure; the upper half of the thermocouple 2 is embedded in the encapsulation material; the bottom end of the π-type thermocouple interconnect array is embedded in the substrate layer 6; the substrate layer 6 is connected to the reversible adhesion layer 5 through the connecting material 4.

[0044] The method for fabricating the reversibly adhered flexible semiconductor cooling device includes the following steps:

[0045] S1. Preparation of raw materials:

[0046] (1) Preparation of encapsulation material: Mix the matrix material and filler in a mass ratio of 1:(0.5-2) (e.g., 1:2) and stir evenly in a mixer to obtain a mixture. Add curing agent and stir evenly to obtain encapsulation material;

[0047] (2) Preparation of reversible adhesive layer material: Water, acrylamide, anhydrous sodium sulfate and borax are mixed and stirred at 50°C for 30 minutes. Then, 1 wt% of oxidized carboxymethylated nanocellulose (TOCNF) dispersion is added and stirred until homogeneous. Then, the catalyst tetramethylethylenediamine (TEMED) and the crosslinking agent N,N'-methylenebisacrylamide (MBAA) are added and stirred for 15 minutes. Finally, the thermal initiator ammonium persulfate (APS) is added.

[0048] (3) Preparation of base layer material: Add a reinforcing phase with a volume fraction of 2-60% (e.g., 60%) to the matrix material, stir evenly with a mixer, add curing agent, stir evenly, and obtain base layer material;

[0049] Fabrication of S2 and π-type thermocouple interconnect arrays:

[0050] Two sets of metal electrode plates matching the size of the thermocouple are prepared by transfer printing or laser cutting. The thermocouple material is placed between the two sets of metal electrode plates. The thermocouple is connected to the metal plate by hot pressing welding to form a thermal parallel and electrical series structure. Then the encapsulation material prepared in step (1) is poured into the interconnect structure, heated to 80°C to solidify and cut to obtain a π-type thermocouple interconnect array.

[0051] S3. Fabrication of reversible adhesion substrate:

[0052] Place the connecting material into a square mold, pour in the reversible adhesion layer material prepared in step (2), and polymerize at 70°C for 1 hour. After polymerization, wash away the unreacted monomers with deionized water to obtain a reversible adhesion substrate; wherein, the thickness of the reversible adhesion layer is half the thickness of the connecting material.

[0053] S4. Fabrication of reversibly adhered flexible semiconductor cooling devices:

[0054] The π-type thermocouple interconnect array prepared in step S2 is coated with a colloidal binder (Sil-Poxy™) and adhered to the reversible adhesive substrate prepared in step S3. The substrate material prepared in step (3) is then poured in and heated to cure at 40-100℃ to obtain a reversibly adhesive flexible semiconductor refrigeration device. The thickness of the substrate layer is the same as the thickness of the connecting material.

[0055] In the following optional embodiments of the present invention, in step (1) of preparing the encapsulation material, the matrix material is selected from polyurethane, polydimethylsiloxane (PDMS), or epoxy resin; the filler is selected from silica microspheres (particle size of 30-700 μm), aerogel, or vermiculite. Exemplarily, in the following preferred embodiments of the present invention, the matrix material of the encapsulation material is polydimethylsiloxane, and the filler is silica microspheres.

[0056] In the following optional embodiments of the present invention, in the preparation process of the reversible adhesive layer material in step (2) of S1, the ratio of water, acrylamide, anhydrous sodium sulfate, borax, TOCNF, catalyst, crosslinking agent and thermal initiator is 10mL∶1g∶1g∶0.38g∶5.36g∶50μL∶0.005g∶0.01g.

[0057] In the following optional embodiments of the present invention, in step (3) of S1, during the preparation of the substrate material, the matrix material is selected from polyurethane, polydimethylsiloxane (PDMS), or biodegradable plastic (Ecoflex); the reinforcing phase is selected from at least one of liquid metal, silver nanowires, copper nanoparticles, boron nitride, aluminum nitride, alumina, and graphene. Exemplarily, in the following preferred embodiments of the present invention, the matrix material of the substrate material is polydimethylsiloxane, and the reinforcing phase is a mixture of liquid metal and copper nanoparticles.

[0058] In the following optional embodiments of the present invention, in S2, the metal electrode plate is a copper sheet with a thickness of 0.05 mm. The thermoelectric couple material is selected from chalcogenide thermoelectric materials based on (Bi,Sb)2(Te,Se)3, MgAgSb, Mg3(Bi,Sb)2, Ag2Se, or SnSe. Exemplarily, in the following preferred embodiments of the present invention, in the thermoelectric couple, the P-type semiconductor thermoelectric arm is bismuth telluride (Bi). 0.5 Sb 1.5 Te3 or MgAg 0.95 Sb 0.99 N-type semiconductor thermoelectric arm bismuth telluride (Bi₂Se) 0.3 Te 2.7 or Mg 3.2 Bi 1.49 Sb 0.5 Se 0.01 .

[0059] In the following optional embodiments of the present invention, in S3, the connecting material is selected from nickel foam, titanium foam, or foam, and has a thickness of 0.5-2 mm. Exemplarily, in the following preferred embodiments of the present invention, the connecting material is nickel foam or titanium foam, and has a thickness of 1 mm or 1.5 mm.

[0060] The reversibly adhesive flexible semiconductor cooling device prepared by this invention can be applied in wearable electronic devices, micro medical devices, or portable devices.

[0061] Unless otherwise specified, "room temperature" in this invention refers to 25±2℃.

[0062] All raw materials used in this invention were purchased from the market.

[0063] The technical solution of the present invention will be further illustrated by the following embodiments.

[0064] Example 1

[0065] A method for fabricating a reversibly adhesive flexible semiconductor cooling device includes the following steps:

[0066] S1. Preparation of raw materials:

[0067] (1) Preparation of encapsulation material: Weigh 20g of PDMS prepolymer (brand name: Dow Corning 184 - main agent, a prepolymer of vinyl PDMS that provides the main skeleton structure of the elastomer) and 40g of silica microspheres (3M-A16) and stir them evenly in a mixer to obtain a mixture. Then add 2g of PDMS curing agent (brand name: Dow Corning 184 - curing agent, which contains hydrosilicone oil and platinum catalyst, so that the vinyl PDMS prepolymer in the main agent crosslinks with the Si-H groups in the curing agent and forms a three-dimensional network structure through an addition reaction). Stir evenly to obtain the encapsulation material.

[0068] (2) Preparation of reversible adhesive layer material: Take 10 mL of water, add 1 g of acrylamide, 1 g of anhydrous sodium sulfate and 0.38 g of borax, stir in a water bath at 50 °C for 30 minutes, add 5.36 g of 1 wt% TOCNF dispersion, stir evenly, add 50 μL of tetramethylethylenediamine (TEMED) and 0.005 g of MABA, continue stirring for 15 minutes, add 0.01 g of ammonium persulfate (APS) to obtain reversible adhesive layer material;

[0069] (3) Preparation of substrate material: Take 7g of PDMS prepolymer (containing 10wt% diluent to reduce viscosity, the diluent is FKL-1840 special diluent for FKL 184), 60g of gallium indium alloy (GaIn, composed of 75.5wt% Ga and 24.5wt% In) and 27g of copper (10μm, Aladdin) and mix them. Stir evenly with a mixer, add 1.4g of PDMS curing agent, stir evenly, and obtain the substrate material;

[0070] Fabrication of S2 and π-type thermocouple interconnect arrays:

[0071] Prepare a transfer paper, design the upper and lower electrode planar diagrams of the device using CAD and print them out using a printer. Transfer the ink on the transfer paper to a copper sheet (0.05mm) with polyimide high-temperature resistant tape on the back by hot pressing (hot pressing at 200℃ for 2 minutes). The dimensions of the interconnecting electrodes and thermoelectric arms are: length, width and height = 1mm × 1mm × 5mm. Finally, the upper and lower metal electrode plates are obtained by etching.

[0072] Apply solder paste (Sn) to the upper and lower metal electrode plates. 95 Sb5), and a P-type semiconductor thermoelectric arm with dimensions of 1mm × 1mm × 5mm (bismuth telluride Bi). 0.5 Sb 1.5 Te3 and N-type semiconductor thermoelectric arms bismuth telluride Bi2Se 0.3 Te 2.7 Arranged on matching electrode plates, thermocouples are connected to metal plates by hot-press welding to form a thermal parallel and electrical series structure. Then, the encapsulation material prepared in step (1) is poured into the interconnect structure, heated to 80°C to solidify and cut to obtain a π-type thermocouple interconnect array.

[0073] S3. Fabrication of reversible adhesion substrate:

[0074] Place the connecting material (1 mm thick titanium foam) into a square mold, pour in the reversible adhesion layer material prepared in step (2), and polymerize at 70°C for 1 hour. After polymerization, wash away the unreacted monomers with deionized water to obtain a reversible adhesion substrate; wherein, the thickness of the reversible adhesion layer is half the thickness of the connecting material.

[0075] S4. Fabrication of reversibly adhered flexible semiconductor cooling devices:

[0076] In step S2, a sil-poxy™ adhesive is applied to the bottom of the π-type thermocouple interconnect array and adhered to the reversible adhesive substrate prepared in step S3. The substrate material prepared in step (3) is then poured on and heated to cure, resulting in a reversibly adhesive flexible semiconductor refrigeration device (see physical image). Figure 3 (as shown in the figure). The thickness of the base layer is the same as the thickness of the connecting material.

[0077] Example 2

[0078] Same as Example 1, except that the P-type semiconductor thermoelectric arm Bismuth telluride with dimensions of 1mm × 1mm × 5mm in step S2 is used. 0.5 Sb 1.5 Te3 and N-type semiconductor thermoelectric arms bismuth telluride Bi2Se 0.3 Te 2.7Replaced with: a P-type semiconductor thermoelectric arm of bismuth telluride (MgAg) with dimensions of 1.5mm × 1.5mm × 3mm. 0.95 Sb 0.99 Bismuth telluride Mg and N-type semiconductor thermoelectric arms 3.2 Bi 1.49 Sb 0.5 Se 0.01 .

[0079] Example 3

[0080] Same as Example 1, except that the 1 mm thick titanium foam in step S3 is replaced with a 1.5 mm thick nickel foam.

[0081] Comparative Example 1

[0082] Same as Example 1, except that no reversible adhesion layer is added.

[0083] Performance testing:

[0084] 1. The reversibly adhesive flexible semiconductor cooling device prepared in Example 1 was subjected to adhesion force testing. The specific method is as follows:

[0085] S1. Sample preparation:

[0086] The reversible adhesive flexible semiconductor cooling device prepared in Example 1 was used as a test sample. The device has a built-in temperature control function and a temperature-controlled reversible adhesive material layer on one side.

[0087] S2. Experimental equipment and substrate:

[0088] A universal tensile testing machine (with a data acquisition computer), a temperature monitoring instrument (with thermocouples), and a regulated DC power supply (adjustable current) were used; glass and aluminum plates were selected as the test substrates.

[0089] S3. Experimental Procedure:

[0090] (1) Sample fixation and pre-conditioning of cooling temperature: one side of the test sample ( Figure 3 The sample (top surface) is fixed to the test substrate (initially a glass substrate, later replaced with an aluminum substrate) with strong adhesive, ensuring a firm and secure connection between the sample and the substrate. A thermocouple from a temperature monitoring device is placed on the surface of the reversible adhesion layer of the sample, ensuring close contact between the thermocouple and the sample surface. The test sample is connected to a regulated DC power supply, set to output a constant current of 0.1A, and the cooling program is started. The temperature change of the sample surface is monitored in real time using the temperature monitoring device. The current is adjusted to regulate the sample temperature to 20℃, and this temperature is maintained for 30 minutes after stabilization. After confirming no temperature fluctuations, the thermocouple is removed (to avoid interfering with subsequent adhesion operations), and the DC power supply is kept continuously supplying a constant current to maintain the sample temperature.

[0091] (2) Reversible Adhesive Layer Bonding and Fixing: Precisely bond the other end of the test sample with the reversible adhesive layer to the corresponding position on the same type of test substrate (glass / aluminum plate) to ensure alignment. Apply a constant pressure of 2N to the bonding area and hold for 10 minutes to ensure that the reversible adhesive layer and the substrate are completely and tightly bonded. Record the overlap area between the two. During the pressure application, keep the DC power supply continuously supplying a constant current to ensure that the sample temperature remains stable at the set 20℃.

[0092] (3) Tensile test and adhesive strength calculation: The fixed sample and the substrate are placed horizontally and fixed in a universal tensile testing machine. The DC power supply is kept at a constant current to maintain the sample temperature. The testing machine is set to stretch at a constant speed of 5 mm / min until the reversible adhesive layer is completely separated from the test substrate. The tensile force change curve is recorded by the matching computer, and the adhesive strength value at the corresponding temperature is calculated according to the formula adhesive strength (kPa) = maximum tensile force / overlapping area.

[0093] (4) Keep the above test parameters and operation steps unchanged, repeat steps (1)-(3) for glass and aluminum plates at 20℃ and 40℃ respectively, complete all group tests, and ensure the repeatability and accuracy of experimental data.

[0094] Figure 4 This is a comparison of the adhesion forces of the reversibly adhesive flexible semiconductor cooling device prepared in Example 1 at different temperatures and on different materials. Figure 4 As can be seen, when the temperature of the semiconductor cooling device is controlled at 20℃, the device exhibits high adhesion strength on both glass and aluminum plate surfaces. At 40℃, the adhesion strength decreases significantly, realizing the controllable switching of the adhesion performance of the flexible semiconductor cooling device with reversible adhesion at different temperatures. When the temperature is adjusted to above 40℃, the adhesion strength drops to 0.2kPa, and the device can be easily peeled off from the heat source.

[0095] 2. The refrigeration performance of the samples prepared in Example 1 and Comparative Example 1 was tested. The specific methods are as follows:

[0096] S1. Preparation of experimental samples and equipment:

[0097] (1) Preparation of simulated human skin: The prepolymer of PDMS (Dow Corning 184) and the curing agent were mixed at a mass ratio of 10:1. After degassing, the mixture was poured into a 5cm×5cm×1cm mold and cured at 80℃ for 2h to obtain a PDMS block that simulates human skin.

[0098] (2) Test samples: Take one reversibly adhesive flexible semiconductor refrigeration device prepared in Example 1 and one non-reversibly adhesive flexible semiconductor refrigeration device prepared in Comparative Example 1;

[0099] (3) Experimental equipment: 34℃ constant temperature heating table, silicone oil, temperature monitoring instrument (with thermocouple), regulated DC power supply (current adjustable), fan + air duct channel (including current regulator to change wind speed), anemometer, human test volunteers (in compliance with ethical standards);

[0100] S2. Construction of a simulated human skin heat transfer system:

[0101] (1) Apply a layer of silicone oil evenly to the surface of the heating table with the temperature set at 34℃ to improve the heat transfer efficiency;

[0102] (2) Place the prepared PDMS simulated skin (5cm×5cm×1cm) horizontally on the silicone oil coating surface of the heating table to ensure that the two are in close contact and construct a human skin heat transfer simulation device.

[0103] S3, Simulated system refrigeration performance test:

[0104] (1) Natural convection conditions test:

[0105] Sample bonding and temperature measurement setup: The reversible adhesive layer of the sample from Example 1 was bonded to the surface of the PDMS simulated skin. The thermocouple of the temperature monitoring instrument was placed at the interface between the sample and the PDMS to ensure that the thermocouple was in close contact with the interface to collect temperature data in real time. The sample from Comparative Example 1 was bonded to the new PDMS simulated skin surface in the same way, and the thermocouple was placed simultaneously.

[0106] Power supply and cooling test: Connect the sample of Example 1 to a regulated DC power supply, first apply a constant current of 0.1A to start the cooling program, and record the interface temperature change in real time with a temperature monitoring instrument until the temperature stabilizes; then adjust the current to 0.2A-2.0A in sequence, and record the corresponding cooling temperature (the temperature value of the device reduction) after each current stabilizes, to complete the full current range test.

[0107] Control test: Keep the natural convection (no wind) environment unchanged, connect the sample of Comparative Example 1 to a regulated DC power supply, and repeat the test according to the same current gradient (0.1A-2.0A) as described above, and record the cooling temperature data at each current.

[0108] (2) Forced convection condition test:

[0109] Convection system setup: A forced convection device was built using a fan and airflow channels. The wind speed was calibrated using an anemometer, adjusted to 1.5 m / s and kept stable. The PDMS simulated skin with the test sample attached was placed in the convection device to ensure that the airflow was uniformly flowing over the sample surface.

[0110] Cooling performance test: Repeat the power supply and data recording steps in the "natural convection test" (current 0.1A-2.0A) for the samples of Example 1 and Comparative Example 1 respectively, record the cooling temperature under different currents and wind speeds of 1.5m / s in real time, and compare the difference in cooling effect between forced convection and natural convection.

[0111] S4. Actual human body cooling performance test:

[0112] (1) Select healthy volunteers, clean their smooth skin areas (such as the forearm), and directly attach the reversible adhesive layer of the sample from Example 1 to the human skin surface. Place a thermocouple at the contact interface to connect a temperature monitoring instrument.

[0113] (2) Connect the sample to a regulated DC power supply and supply power in sequence according to the current gradient of 0.1A-2.0A. Record the temperature change of the human skin contact area (the temperature drop of the device) under each current in real time.

[0114] (3) Remove the sample from Example 1, attach the sample from Comparative Example 1 directly to the same skin area of ​​the volunteer, repeat the test according to the same current gradient as above, and record the corresponding cooling temperature data.

[0115] (4) Human body tests were conducted under natural convection (no wind) and forced convection (1.5 m / s) conditions to ensure that the test environment was consistent with the simulation system.

[0116] Figure 5 The figures show the cooling performance of the samples prepared in Example 1 and Comparative Example 1 when applied to the human body. As can be seen from the figures, compared with semiconductor thermoelectric devices without a reversible adhesion layer, the device of the present invention can improve the cooling capacity of human skin by more than 33.3%.

[0117] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A reversibly adhesive flexible semiconductor cooling device, characterized in that, The structure includes: π-type thermocouple interconnect array, substrate, connecting material and reversible adhesion layer; The π-type thermocouple interconnect array includes: encapsulation material, interconnect electrodes, and thermocouples; wherein, the thermocouples include N-type semiconductor thermocouple arms and P-type semiconductor thermocouple arms, which are arranged at intervals and interconnected at their top ends by interconnect electrodes to form π-type thermocouple interconnect units, and the bottom ends of two π-type thermocouple interconnect units are interconnected by interconnect electrodes to form a π-type thermal parallel and electrical series structure; the upper half of the thermocouple is embedded in the encapsulation material; The bottom end of the π-type thermocouple interconnect array is embedded in the substrate layer; The base layer is connected to the reversible adhesion layer via a connecting material; The material of the reversible adhesion layer is a phase change temperature-controlled reversible adhesion material; The preparation method of the phase change temperature-controlled reversible adhesive material includes the following steps: mixing water, acrylamide, anhydrous sodium sulfate and borax and heating and stirring, adding oxidized carboxymethylated nanocellulose, stirring evenly and then adding catalyst and crosslinking agent, continuing to stir, adding thermal initiator, and obtaining phase change temperature-controlled reversible adhesive material.

2. The reversibly adhesive flexible semiconductor cooling device according to claim 1, characterized in that, The substrate layer is prepared from matrix material and reinforcing phase as raw materials; The matrix material is selected from polyurethane, polydimethylsiloxane, or biodegradable plastic; The reinforcing phase is selected from at least one of liquid metal, silver nanowires, copper nanoparticles, boron nitride, aluminum nitride, aluminum oxide, and graphene.

3. The reversibly adhesive flexible semiconductor cooling device according to claim 1, characterized in that, The connecting material is selected from nickel foam, titanium foam, or foam, with a thickness of 0.5-2mm.

4. The reversibly adhesive flexible semiconductor cooling device according to claim 1, characterized in that, The encapsulation material is prepared from a matrix material and fillers as raw materials; The matrix material is selected from polyurethane, polydimethylsiloxane, or epoxy resin; The filler is selected from silica microspheres, aerogels, or vermiculite.

5. The reversibly adhesive flexible semiconductor cooling device according to claim 1, characterized in that, The interconnecting electrodes are made of conductive metal.

6. The reversibly adhesive flexible semiconductor cooling device according to claim 1, characterized in that, The thermoelectric pair material is selected from chalcogenide thermoelectric materials based on (Bi,Sb)2(Te,Se)3, MgAgSb, Mg3(Bi,Sb)2, Ag2Se, or SnSe.

7. A method for fabricating a reversibly adhered flexible semiconductor cooling device as described in any one of claims 1-6, characterized in that, Includes the following steps: The thermocouple material is placed between two sets of metal electrode plates, and the thermocouple is connected to the metal plates by hot pressing welding. Encapsulation material is poured in, cured, and cut to obtain a π-type thermocouple interconnection array. The bonding material is placed in a square mold, the reversible adhesion layer material is poured in, and a polymerization reaction is carried out to obtain a reversible adhesion substrate. A colloidal binder is applied to the bottom of the π-type thermocouple interconnect array and adhered to the reversible adhesive substrate. A base layer material is then poured in and cured to obtain a reversibly adhesive flexible semiconductor refrigeration device.

8. The application of a reversibly adhesive flexible semiconductor cooling device as described in any one of claims 1-6 in wearable electronic devices, micro medical devices, or portable devices.

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