A flexible thin-film thermoelectric sensor that can be easily integrated and its application

Abstract

The present invention discloses a flexible thin-film thermoelectric sensor that can be easily integrated and its application. The thermoelectric sensor comprises a flexible insulating substrate, a bottom electrode, a P-type thermoelectric film, and an N-type thermoelectric film sequentially deposited on the flexible insulating substrate. The P-type thermoelectric film, the bottom electrode, and the N-type thermoelectric film are connected end to end and deposited in a "snake-like" pattern on the flexible insulating substrate. The present invention uses a flexible insulating substrate to deposit the thermoelectric thin-film material, meeting the flexibility requirements of the temperature sensor and being suitable for accurate temperature measurement in complex application environments. In practical applications, the temperature sensor can be directly attached to the periphery of a heat source and converts the temperature difference signal into a voltage signal through the Seebeck effect. The sensor has an extremely fast response speed, does not require external power supply, has a simple structure, low process cost, high reliability, can generate a large temperature difference, and has high sensitivity.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal management of electronic devices, and in particular relates to a flexible thin-film thermoelectric sensor that can be easily integrated and applications thereof. Background Art

[0002] With the improvement of microsystem integration and microsystem operating frequency, the power consumption of microsystems continues to increase, and various thermal management problems caused by temperature are becoming increasingly prominent. For this reason, researchers at home and abroad have carried out in-depth research on solving the problem of dynamic temperature management in small areas, and temperature sensors have therefore become the focus of research at home and abroad.

[0003] Traditional temperature sensors include thermocouples, platinum resistance thermocouples, and bimetallic switches. However, these sensors are limited in their application in microsystems due to factors such as package size, linear performance, accuracy, and spatiotemporal resolution. With the advancement of integrated technology, device units capable of temperature sensing in silicon-based semiconductor integrated circuits include integrated resistors, MOS transistors, silicon diodes, bipolar transistors, and parasitic bipolar transistors in CMOS processes. These temperature sensors have varying principles and components, all predicated on accurately capturing the temperature distribution on the chip surface. However, these sensors generally suffer from excessive power consumption, which not only causes self-heating and affects temperature measurement accuracy, but also makes accurate temperature measurement difficult in complex application environments (such as curved and irregular surfaces), and complicates integration.

[0004] Therefore, it is very necessary to design and develop a passive flexible temperature sensor that is simple in process, easy to integrate, reliable and durable. Summary of the Invention

[0005] In view of this, the present invention provides a flexible thin-film thermoelectric sensor that can be easily integrated and its application. The sensor can convert the temperature difference signal into a voltage signal under passive conditions, thereby realizing high-precision and high-speed measurement of the near-junction temperature of key chips in the microsystem or the thermal distribution of key positions. It has a simple structure, low process cost and high reliability.

[0006] To achieve this goal, the present invention adopts the following technical solution: a flexible thin-film thermoelectric sensor that can be easily integrated, the thermoelectric sensor comprising: a flexible insulating substrate and a bottom electrode, a P-type thermoelectric film, and an N-type thermoelectric film sequentially deposited on the flexible insulating substrate, the P-type thermoelectric film, the bottom electrode, and the N-type thermoelectric film being connected end to end and deposited in a "snake-like" shape on the flexible insulating substrate.

[0007] Preferably, the material of the flexible insulating substrate is any one of polyimide, silicone rubber, silicone resin, polyethylene terephthalate and polyethylene naphthalate.

[0008] Preferably, the materials of the P-type thermoelectric film and the N-type thermoelectric film are both silicon-based materials.

[0009] Preferably, the silicon-based material includes but is not limited to crystalline silicon germanium and heavily doped silicon.

[0010] Preferably, the materials of the P-type thermoelectric film and the N-type thermoelectric film are one or more of Bi2Te3-based thermoelectric materials, Sb2Te3-based thermoelectric materials, SiGe alloy materials, semi-Halles compound thermoelectric materials, PbTe-based thermoelectric materials, skutterudite or filled skutterudite thermoelectric materials.

[0011] Preferably, the bottom electrode is made of any one of metals copper, aluminum, gold, silver, chromium and alloys.

[0012] Preferably, the P-type thermoelectric film and the N-type thermoelectric film are both deposited on the flexible insulating substrate by magnetron sputtering at room temperature, and are patterned by physical blocking of a metal mask or a photolithography mask.

[0013] Preferably, the bottom electrode is deposited on the flexible insulating substrate by magnetron sputtering at room temperature, and the bottom electrode is patterned by photolithography, etching, and debonding.

[0014] Preferably, one end of the thermoelectric sensor is connected to an external device via a compensation wire.

[0015] An application of a flexible thin-film thermoelectric sensor that can be easily integrated. The application uses the above-mentioned flexible thin-film thermoelectric sensor that can be easily integrated to perform temperature monitoring. During temperature monitoring, the flexible thin-film thermoelectric sensor is directly attached to the heat source of the device to be monitored.

[0016] The beneficial effects of the present invention are: the present invention provides a flexible thin-film thermoelectric sensor that can be easily integrated and its application, wherein the thermoelectric sensor uses a flexible insulating substrate to deposit the thermoelectric thin-film material, meets the flexibility requirements of the temperature sensor, and is suitable for accurate temperature measurement in complex application environments. In practical applications, the temperature sensor can be directly attached to the surroundings of the heat source, and the temperature difference signal is converted into a voltage signal through the Seebeck effect. It has an extremely fast response speed, does not require external power supply, has a simple structure, low process cost, high reliability, can generate a large temperature difference, and has high sensitivity. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Schematic diagram of the structure of a flexible thin film thermoelectric sensor that can be easily integrated in an embodiment of the present invention;

[0018] Figure 2 This is a distribution diagram of a flexible thin film thermoelectric sensor that can be easily integrated in an embodiment of the present invention when in use;

[0019] Figure 3 A diagram showing the relationship between temperature and Seebeck voltage of the flexible thin film thermoelectric sensor that can be easily integrated in the present invention;

[0020] In the figure: 1. P-type thermoelectric film 2. N-type thermoelectric film 3. Bottom electrode 4. Flexible insulating substrate 5. Heat source 100. Flexible thin-film thermoelectric sensor that can be easily integrated. DETAILED DESCRIPTION

[0021] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and it should be understood that the scope of protection of the present invention is not limited to such specific descriptions and embodiments. Those skilled in the art can make various other specific variations and combinations based on the technical teachings disclosed in the present invention without departing from the essence of the present invention, and such variations and combinations are still within the scope of protection of the present invention.

[0022] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] A flexible thin film pyroelectric sensor 100 that can be easily integrated, such as Figure 1 As shown, the thermoelectric sensor includes: a flexible insulating substrate 4 and a P-type thermoelectric film 1, an N-type thermoelectric film 2 and a bottom electrode 3 sequentially deposited on the flexible insulating substrate 4, and the P-type thermoelectric film 1, the bottom electrode 3 and the N-type thermoelectric film 2 are connected end to end and arranged in a "snake" shape on the flexible insulating substrate 4. When used, the flexible thin film thermoelectric sensor that can be easily integrated according to the present invention is directly attached to the surroundings of the heat source, such as Figure 2 As shown, the temperature difference signal is converted into a voltage signal through the Seebeck effect, no external energy supply is required, and the structure is simple, the process cost is low, and the reliability is high.

[0024] The material of the above-mentioned flexible insulating substrate 1 is any one of polyimide, silicone rubber, silicone resin, polyethylene terephthalate and polyethylene naphthalate; the materials of the P-type thermoelectric film 1 and the N-type thermoelectric film 2 are both silicon-based materials such as crystalline silicon germanium and heavily doped silicon, or can be one or more of Bi2Te3-based thermoelectric materials, Sb2Te3-based thermoelectric materials, SiGe alloy materials, semi-Halles compound thermoelectric materials, PbTe-type thermoelectric materials, skutterudite or filled skutterudite thermoelectric materials; the material of the bottom electrode 3 is any one of metal copper, aluminum, gold, silver, chromium and alloys.

[0025] The P-type and N-type thermoelectric films 1 and 2 are deposited on a flexible insulating substrate 4 at room temperature using magnetron sputtering and patterned using either physical blocking with a metal mask or a photolithography mask. The bottom electrode 3 is also deposited on the flexible insulating substrate 4 at room temperature using magnetron sputtering and patterned using photolithography, etching, and debonding. One end of the thermoelectric sensor is connected to an external device via a compensation wire.

[0026] An application of a flexible thin-film thermoelectric sensor that can be easily integrated. The application uses the above-mentioned flexible thin-film thermoelectric sensor that can be easily integrated to perform temperature monitoring. During temperature monitoring, the flexible thin-film thermoelectric sensor is directly attached to the heat source of the device to be monitored.

[0027] The present invention is based on the Seebeck effect in the thermoelectric effect. The hot end of the sensor is placed in a heat source with a higher temperature to be measured, so that a certain temperature gradient is generated between the hot end and the cold end of the sensor. Then, the temperature signal is converted into a voltage signal through the Seebeck effect. By calibrating the sensor, the relationship between the hot end heat source temperature and the output voltage signal can be obtained. After calibration, the hot end temperature can be obtained through the output voltage signal, that is, the chip temperature can be monitored. Figure 3 The figure shows the relationship between the temperature and Seebeck voltage of the temperature sensor. The linear equation obtained by calculation is E = 5.71429 × 10-6 + 0.012 × ΔT, R2 = 1, where E is the Seebeck voltage and ΔT is the temperature difference between the hot end and the cold end of the temperature sensor.

Claims

1. A flexible thin film thermoelectric sensor that can be easily integrated, characterized in that: When used, it is directly attached around the heat source. The thermoelectric sensor includes: a flexible insulating substrate and a bottom electrode, a P-type thermoelectric film and an N-type thermoelectric film deposited in sequence on the flexible insulating substrate. The P-type thermoelectric film, the bottom electrode and the N-type thermoelectric film are connected end to end and deposited in a "snake" shape on the flexible insulating substrate.

2. The flexible thin film thermoelectric sensor that can be easily integrated according to claim 1, characterized in that: The material of the flexible insulating substrate is any one or more of polyimide, silicone rubber, silicone resin, polyethylene terephthalate and polyethylene naphthalate.

3. The flexible thin film thermoelectric sensor that can be easily integrated according to claim 1, characterized in that: The materials of the P-type thermoelectric film and the N-type thermoelectric film are both silicon-based materials.

4. The flexible thin film thermoelectric sensor that can be easily integrated according to claim 3, characterized in that: The silicon-based material includes but is not limited to crystalline silicon germanium and heavily doped silicon.

5. The flexible thin film thermoelectric sensor that can be easily integrated according to claim 1, characterized in that: The materials of the P-type thermoelectric film and the N-type thermoelectric film are one or more of Bi2Te3-based thermoelectric materials, Sb2Te3-based thermoelectric materials, SiGe alloy materials, semi-Halles compound thermoelectric materials, PbTe-based thermoelectric materials, skutterudite or filled skutterudite thermoelectric materials.

6. The flexible thin film thermoelectric sensor capable of being easily integrated according to claim 1, characterized in that: The bottom electrode is made of any one of copper, aluminum, gold, silver, chromium and alloys.

7. The flexible thin film thermoelectric sensor capable of being easily integrated according to claim 1, characterized in that: The P-type thermoelectric film and the N-type thermoelectric film are both deposited on a flexible insulating substrate at room temperature by magnetron sputtering, and are patterned by physical shielding of a metal mask or a photolithography mask.

8. The flexible thin film thermoelectric sensor capable of being easily integrated according to claim 1, characterized in that: The bottom electrode is deposited on a flexible insulating substrate at room temperature by a magnetron sputtering method, and the bottom electrode is patterned by photolithography, etching, and degumming.

9. The flexible thin film thermoelectric sensor capable of being easily integrated according to claim 1, characterized in that: One end of the thermoelectric sensor is connected to an external device through a compensation wire.

10. An application of a flexible thin film thermoelectric sensor that can be easily integrated, characterized in that: The application utilizes the easily integrated flexible thin film thermoelectric sensor according to any one of claims 1 to 9 to perform temperature monitoring. During temperature monitoring, the flexible thin film thermoelectric sensor is directly attached around the heat source of the device to be monitored.

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