Preparation method of temperature enhanced photoelectric detector, early warning Internet of Things system and working method

Abstract

The invention belongs to the field of temperature alarm systems, discloses a preparation method of a temperature enhanced photoelectric detector, an early warning Internet of Things system and a working method, adopts an Nb3Se12I semiconductor material and constructs a quasi-one-dimensional nanowire structure, overcomes the defects that a traditional photoelectric detector works at normal temperature, and the performance of the traditional photoelectric detector is reduced along with temperature rise, and improves the performance of the early warning Internet of Things system. The material has excellent thermal stability and electronic structure characteristics, and can maintain and even enhance photoelectric response in a high-temperature environment. The quasi-one-dimensional nanowire structure improves the specific surface area and the carrier migration efficiency, and further enhances the photoelectric conversion performance under thermal excitation; the interdigital electrode structure provides a high-sensitivity signal acquisition capability, has strong adaptability, and is convenient for integration and mass production. Finally, when the temperature rises, the performance of the detector does not decline, but the response is enhanced, and the detector is especially suitable for intelligent early warning scenes in which temperature and illumination changes need to be monitored synchronously.

Description

Technical Field

[0001] This invention belongs to the field of temperature alarm systems, specifically relating to the preparation method of a temperature-enhanced photodetector, an early warning Internet of Things system, and its operating method. Background Art

[0002] As electronic devices become increasingly integrated and application environments become more complex, devices operating at high power densities often face risks of overload, overheating, and even fire. Traditional overload and fire early warning systems mostly rely on indirect methods such as thermistors, infrared sensors, or smoke detectors for early warning. These methods suffer from slow response times, limited accuracy, and lack real-time physical quantity coupling sensing capabilities. Furthermore, some sensors exhibit poor stability under high-temperature conditions, prone to drift and failure, making them unsuitable for continuous monitoring tasks in harsh high-temperature environments.

[0003] In recent years, sensors based on novel optoelectronic materials have attracted attention due to their high sensitivity and fast response capabilities. However, most existing photodetectors operate at room temperature, and their photoelectric performance typically decreases with increasing temperature, limiting their application in high-temperature fields. This is especially true in intelligent early warning scenarios that require simultaneous monitoring of temperature rise and changes in illumination, where stable and integrable material systems and device solutions are still lacking.

[0004] Patent CN119092587A discloses a photodetector based on anisotropic photothermal materials, its preparation method, and its encryption method, which mentions a Nb3Se... 12 I-nanowire photodetectors are extremely small in size, making them suitable for miniaturization applications. This material is easy to integrate into microelectronic devices, which helps to improve the integration level of the devices. In the field of microelectronics, this material shows significant advantages, especially in reducing device size and improving integration.

[0005] Therefore, there is an urgent need for a photodetector with high-temperature stability and temperature-enhanced photoelectric response characteristics to achieve rapid and accurate early warning of overload, overheating and potential fire risks of electronic equipment. This is especially important in smart home and industrial Internet of Things scenarios, and has broad application prospects. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of existing photodetectors, which operate at room temperature and whose photoelectric performance usually decreases with increasing temperature, thus limiting their application in intelligent early warning scenarios that require simultaneous monitoring of temperature rise and light changes. This invention provides a method for preparing a temperature-enhanced photodetector, an early warning IoT system, and a method for its operation.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a temperature-enhanced photodetector, comprising the following steps: According to Nb3Se 12 The stoichiometric ratio of each element in I is used to weigh Nb powder, Se powder and I crystal with a purity of 99.999%, and the Nb powder, Se powder and I crystal are synthesized into a semiconductor material by chemical vapor transport method. Photoresist is spin-coated onto a blank substrate, and a hollow interdigitated electrode pattern is photolithographically formed on the photoresist. A substrate with an interdigitated electrode structure having a source and a drain is fabricated based on the interdigitated electrode pattern. Semiconductor material is placed in anhydrous ethanol and subjected to ultrasonic treatment to separate the semiconductor material into quasi-one-dimensional nanowire material structures. Anhydrous ethanol dispersion of the quasi-one-dimensional nanowire material structures is dropped onto a substrate with a prepared interdigitated electrode structure and allowed to dry naturally. The dried substrate is then subjected to annealing post-treatment to obtain a temperature-enhanced photodetector.

[0008] A further improvement of the present invention is that, when fabricating a substrate with an interdigitated electrode structure having a source and a drain based on the interdigitated electrode pattern, a resistive thermal evaporation technique and a lift-off process are used.

[0009] A further improvement of the present invention is that when annealing the dried substrate, the annealing temperature is 120°C and the annealing time is 6 hours.

[0010] A further improvement of this invention is that I crystal is used as a transport agent, and the content of the transport agent is 2 mg / cm³. 3 .

[0011] A further improvement of this invention lies in Nb3Se 12 The Se vacancy concentration in I nanowires is 5%-10%.

[0012] A further improvement of the present invention is that the channel length of the interdigitated electrode is 30 µm and the channel width is 5 mm.

[0013] Secondly, the present invention provides an early warning Internet of Things system based on a temperature-enhanced photodetector, comprising: Temperature-enhanced photodetectors, employing Nb3Se... 12 A photodetector made of 1 nanowires is used to receive temperature and light intensity output current signals and send them to the control unit. The microcontroller unit is used to compare the current signal with a preset threshold and generate a control signal, which is then sent to the audible and visual alarm device, the relay control unit, and the wireless transmission module. An audible and visual alarm device is used to trigger an alarm based on received control signals. The relay control unit is used to shut off the power supply based on the received control signal; The wireless transmission module is used to send control information to the host computer.

[0014] A further improvement of this invention lies in that it is based on Nb3Se 12 The 1-nanowire photodetector includes a substrate, a dielectric layer disposed on the substrate, a source electrode and a drain electrode disposed on the dielectric layer, the source electrode and the drain electrode being distributed in the form of interdigitated electrodes, and a semiconductor channel layer between the source electrode and the drain electrode.

[0015] Thirdly, the present invention provides a method for operating an early warning Internet of Things system based on a temperature-enhanced photodetector, comprising the following steps: Based on Nb3Se 12 The photodetector of 1 nanowires collects the temperature and light intensity in the target area in real time and sends a current signal to the control unit. The control unit compares the current signal with a preset threshold. When the current signal is greater than the preset threshold, the control unit generates an alarm signal and a relay control signal. The alarm signal is sent to the audible and visual alarm device, the relay control signal is sent to the relay control unit, and the alarm signal and the relay control signal are sent together to the wireless transmission module. The audible and visual alarm device will trigger an audible and visual alarm based on the received alarm signal; The relay control unit controls the power supply to be turned off based on the received relay control signal; The wireless transmission module is used to send alarm signals and relay control signals to the host computer.

[0016] A further improvement of this invention is that the host computer performs remote monitoring and display based on the received alarm signals and relay control signals.

[0017] Compared with the prior art, the present invention has the following beneficial effects: This invention uses Nb3Se 12 By constructing a quasi-one-dimensional nanowire structure using semiconductor materials, this method overcomes the shortcomings of traditional photodetectors, which operate at room temperature and whose performance decreases with increasing temperature. It exhibits excellent thermal stability and electronic structure characteristics, maintaining or even enhancing photoelectric response at high temperatures. The quasi-one-dimensional nanowire structure increases specific surface area and carrier migration efficiency, further enhancing photoelectric conversion performance under thermal excitation. The interdigitated electrode structure provides high-sensitivity signal acquisition capabilities, strong adaptability, and ease of integration and mass production. In conclusion, this detector not only maintains its performance but also enhances its response with increasing temperature, making it particularly suitable for intelligent early warning scenarios requiring simultaneous monitoring of temperature and light changes, such as forest fire monitoring, equipment overheating alarms, and smart city security sensing, demonstrating promising application prospects.

[0018] The early warning Internet of Things system based on a temperature-enhanced photodetector provided by the present invention uses a photodetector made of Nb3Se 12 I nanowire material, whose optoelectronic performance is enhanced instead when the temperature rises, effectively overcoming the defect that the performance of traditional photodetectors deteriorates at high temperatures, and achieving a highly sensitive detection ability with synergistic enhancement of temperature and light. This system can operate stably in complex environments such as high temperature and high light intensity, significantly improving the environmental adaptability and reliability of the early warning system, and is particularly suitable for scenarios such as fire early warning and industrial high temperature monitoring. The system integrates a microcontroller unit, an acoustic-optic alarm device, a relay control unit, and a wireless transmission module, supports multi-module linkage control, can achieve on-site alarm, power-off protection, and remote information reporting, has the ability of intelligent judgment and rapid response, greatly improves the intelligent level and safety protection ability of the early warning system, and expands the application boundaries of the Internet of Things in the fields of disaster prevention and control, industrial safety, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Optical image of the quasi-one-dimensional semiconductor material Nb3Se 12 I crystal prepared in Example 2; Figure 2 Optical image of the interdigital electrode structure prepared in Example 2; Figure 3 Variation of the photocurrent of the temperature-enhanced photodetector prepared in Example 2 with temperature; Figure 4 Variation of the photocurrent of the temperature-enhanced photodetector prepared in Example 2 with time at different temperatures; Figure 5 Schematic diagram of the working mechanism of the temperature-enhanced photodetector prepared in Example 2; Figure 6 Optical image of the temperature-enhanced photodetector prepared in Example 2 for the overload and fire early warning Internet of Things system; Figure 7 Voltage variation of the temperature-enhanced photodetector prepared in Example 2 at different temperatures; Figure 8 Schematic diagram of the overload warning threshold alarm of the temperature-enhanced photodetector prepared in Example 2 for the overload and fire early warning Internet of Things system; Figure 9 Schematic diagram of the severe overload threshold alarm of the temperature-enhanced photodetector prepared in Example 2 for the overload and fire early warning Internet of Things system. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] To further understand the content of the present invention, the following describes the present invention in detail with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments are only for explaining the present invention rather than limiting it.

[0021] Example 1: A method for fabricating a temperature-enhanced photodetector includes the following steps: Step 1, according to Nb3Se 12 The stoichiometric ratio of each element in I was determined by weighing Nb powder, Se powder, and I crystals with a purity of 99.999% as the basis for synthesizing Nb3Se. 12 The raw material, I crystal, is used as a transport agent and is encapsulated in a vacuum quartz tube. This tube is then placed in a dual-temperature zone tube furnace, and the material is synthesized via chemical vapor transport.

[0022] Step two: First, spin-coat photoresist onto a blank substrate, then use a Heidelberg maskless lithography machine to prepare a hollow interdigitated electrode pattern, and finally use resistive thermal evaporation technology and a lift-off process to prepare a substrate with an interdigitated electrode structure having source and drain electrodes.

[0023] Step three: The semiconductor material synthesized in step one was placed in anhydrous ethanol and sonicated for 2 hours to separate it into quasi-one-dimensional nanowire structures. Then, using a disposable dropper, the anhydrous ethanol dispersion containing the material was vertically dropped onto the prepared interdigitated electrode structure substrate and allowed to air dry. Afterward, it was placed in a tube furnace under an inert gas atmosphere and annealed at 120 °C for 6 hours to ensure good contact characteristics between the nanomaterial and the substrate.

[0024] Step four involves installing the fabricated temperature-enhanced photodetector in a vacuum-conditioned semiconductor optoelectronic performance testing platform. A stable vacuum environment is maintained during testing to prevent interference from adsorbed molecules such as oxygen and water vapor. The device is operated under different temperature conditions by gradually adjusting the heating platform temperature, with a consistent laser irradiation power maintained at each temperature point for full-coverage irradiation. By periodically switching the laser on and off, the photocurrent response of the device at different temperatures is recorded and compared to evaluate its photoelectric performance changes under high-temperature conditions, thereby verifying its temperature-enhanced photoelectric response characteristics.

[0025] Step 5: Place the fabricated temperature-enhanced photodetector with interdigitated electrode structure on a hot stage, and connect the source and drain electrodes to the microcontroller unit respectively. Set an overload warning voltage threshold, and simulate the heating of the device under high load by adjusting the temperature of the hot stage. As the temperature rises, the output voltage of the temperature-enhanced photodetector continuously decreases. When the overload warning temperature is reached, an overload warning is triggered. At this time, the audible and visual alarm device triggers an alarm, and sends an "Overload warning" alarm message to the mobile terminal via wireless communication equipment.

[0026] Step six: Set a severe overload threshold and simulate equipment overheating under load using a heating plate. When the temperature reaches the severe overload temperature, simultaneously apply a lighter flame 5 cm away from the temperature-enhanced photoelectric sensor to simulate a fire caused by severe overload. When the severe overload threshold is reached, the audible and visual alarm device continuously sounds an alarm and activates a relay control switch to disconnect the circuit and prevent further escalation of the accident. Additionally, the wireless communication device sends a "Serious overload" alarm message to the mobile terminal.

[0027] This invention prepares a semiconductor crystal material with a one-dimensional nanowire structure using a chemical vapor transport method. A temperature-enhanced photodetector with an interdigitated electrode structure is then fabricated using anhydrous ethanol dispersion and maskless photolithography combined with resistive thermal evaporation. Utilizing the abundance of Se vacancies within the crystal, the photocurrent increases with increasing temperature. Furthermore, by integrating a power module, microcontroller unit, audible and visual alarm device, relay control unit, and wireless transmission module, the temperature-enhanced photodetector is used in an Internet of Things (IoT) system for overload and fire early warning.

[0028] Example 2: A method for fabricating a temperature-enhanced photodetector includes the following steps: Step 1, according to Nb3Se 12 To determine the stoichiometric ratio of I, Nb powder, Se powder, and I crystals with a purity of 99.999% were weighed out as raw materials, with I element measured at 2 mg / cm³. 3 The density of the material was used as a transport medium. All raw materials were placed in a sealed vacuum quartz tube with an inner diameter of 2 cm and a height of 20 cm, and the tube was evacuated to a vacuum of 5 × 10⁻⁶. -4 Pa. A sealed quartz tube was placed in a dual-temperature zone tube furnace for material synthesis via chemical vapor transport. The mass fractions of Nb, Se, and I were 1 g, 3.6 g, and 0.6 g, respectively. The evaporation zone temperature was set at 600 °C, the growth zone temperature at 480 °C, the heating rate at 1 °C / min, and the growth time at 14 days. Quasi-one-dimensional Nb3Se was obtained after synthesis. 12 I crystal, its macroscopic morphology optical image as follows Figure 1 As shown. Nb3Se 12 The Se vacancy concentration in I nanowires is 5%-10%, Nb3Se 12 I nanowires have high crystallinity and good electrical properties, and the material contains a large number of Se vacancies.

[0029] Step two: Spin-coat AZ5214 photoresist onto a blank silicon wafer substrate with a 285 nm thick silicon dioxide layer. Spin-coating parameters were set to 500 rpm / 5 s and 3000 rpm / 30 s. After spin-coating, the substrate was baked on a 100°C hot plate for 90 s to cure the photoresist layer. Subsequently, a Heidelberg maskless direct-write lithography system was used for pattern exposure, designing a cutout structure for the interdigitated electrode structure. Exposure parameters were set to a Dose of 100 mJ / cm². 2 The defocus was 0. After pattern exposure, a 10 nm thick Cr layer and a 60 nm thick Au layer were deposited sequentially using a resistive thermal evaporation method, with deposition rates controlled at 0.2 Å / s and 0.4 Å / s, respectively. After metal layer deposition, the sample was immersed in acetone heated to 50°C for 30 min for peeling. Then, a disposable dropper was used to gently blow the sample surface to peel off the metal film in the areas covered with photoresist, leaving only the metal pattern of the interdigitated structure in the target area. The sample was then transferred to isopropanol solution and immersed for 1 min to remove residual acetone, then thoroughly rinsed with deionized water and air-dried to obtain source and drain metal patterns with clear interdigitated electrode structures. The optical image of the obtained interdigitated electrode substrate is shown below. Figure 2 As shown.

[0030] Step 3: The semiconductor material Nb3Se synthesized in Step 1 is... 12 The substrate was placed in anhydrous ethanol and sonicated for 2 h to obtain a uniformly dispersed quasi-one-dimensional nanowire structure. Subsequently, a 1 mL disposable dropper was used to vertically drop the anhydrous ethanol dispersion containing the material onto the prepared interdigitated electrode structure substrate, which was then allowed to air dry, allowing the nanowire material to deposit in the electrode gap region. After drying, the substrate with the nanowire material was placed in a tube furnace under an inert gas (argon) atmosphere and annealed at 120 °C for 6 h, maintaining an argon gas flow rate of 50 sccm during annealing to remove residual organic matter and enhance Nb3Se. 12 I. Contact properties between nanowire materials, substrates, and electrodes.

[0031] Step four: Fix the fabricated temperature-enhanced photodetector onto the vacuum semiconductor photoelectric performance testing platform, and connect the source and drain of the device to the testing instrument respectively. Maintain the system vacuum level below 5 × 10⁻⁶ during the testing process. - 4Pa was used to avoid interference from adsorbed molecules such as oxygen and water vapor on device performance. The heating platform temperature was sequentially adjusted to room temperature, 40°C, 50°C, 70°C, 90°C, 110°C, 130°C, 150°C, and 170°C. At each temperature, a 532 nm laser source was used to fully irradiate the device with constant power, while laser switching was performed at 3-second intervals, and the corresponding photocurrent time response was recorded. By comparing the response amplitude and stability under different temperature conditions, the photoelectric performance changes of the device under high-temperature environments were evaluated, verifying its temperature-enhanced photoelectric response behavior and excellent high-temperature operating stability. The photocurrent changes and stability at different temperatures are shown below. Figure 3 and Figure 4 As shown.

[0032] Further analysis revealed that the photocurrent response of the device is significantly modulated by the defect states in the semiconductor channel layer material. Nb3Se 12 The Se vacancies in the I crystal induce defect energy levels within the band gap. At low temperatures, photogenerated electrons and holes are easily trapped by these trap states and cannot participate in conduction. As the temperature increases, the thermal excitation process overcomes the trap binding energy, releasing the carriers in the trap states as free carriers, effectively increasing the carrier concentration and thus enhancing the photoconductive response. This process follows a Boltzmann distribution, exhibiting typical temperature-enhanced photoconductivity behavior. The above response mechanism is as follows: Figure 5 As shown.

[0033] Step 5: Connect the fabricated temperature-enhanced photodetector to the power module and microcontroller. Also connect the audible and visual alarm device, relay control unit, and wireless transmission module to the microcontroller and power module to form a temperature-enhanced photodetector for use in an overload and fire early warning IoT system. The optical image is as follows: Figure 6 As shown. The fabricated temperature-enhanced photodetector with interdigitated electrode structure was then placed on a hot stage, and the stage temperature was set to 50°C, 60°C, 70°C, 80°C, 90°C, and 100°C, respectively. The voltage change of the temperature-enhanced photodetector over time was then measured, as shown. Figure 7 As shown in the diagram, a voltage of 2.3 V at 70 °C is set as the overload warning voltage threshold. The heating effect of the equipment under high load is simulated by adjusting the temperature of the heating platform. As the temperature rises, the voltage output of the temperature-enhanced photodetector continuously decreases. When the overload warning temperature is reached, the voltage falls below 2.3 V, triggering the overload warning. At this point, the audible and visual alarm device is activated, and an "Overload warning" alarm message is sent to the mobile terminal via wireless communication. A schematic diagram of the overload warning threshold alarm is shown below. Figure 8 As shown.

[0034] Step six, similar to step five, sets the voltage of 2.03 V at 100 ℃ as the severe overload voltage threshold, and uses a hot plate to simulate the equipment load heating. When the temperature rises to the severe overload temperature, a lighter flame is simultaneously applied 5 cm from the top of the temperature-enhanced photoelectric sensor to simulate a fire caused by severe overload. The combined effect of the flame and temperature allows the alarm to sound more quickly. When the voltage reaches the severe overload threshold, the audible and visual alarm continuously sounds and activates the relay control switch to disconnect the circuit and prevent further escalation of the accident. Additionally, the wireless communication device sends a "Serious overload" alarm message to the mobile terminal. A schematic diagram of the severe overload threshold alarm is shown below. Figure 9 As shown.

[0035] Example 3: The early warning IoT system based on temperature-enhanced photodetectors includes a temperature-enhanced photodetector, a power module, a microcontroller unit, an audible and visual alarm device, a relay control unit, and a wireless transmission module. The temperature-enhanced photodetector comprises, in sequence: a substrate for supporting the entire detector structure; a dielectric layer formed on the substrate for isolating electrodes; a source and a drain located on the dielectric layer and distributed in the form of interdigitated electrodes; and a semiconductor channel layer located between the source and the drain, having a large number of vacancies to achieve temperature enhancement and thus generate a larger photocurrent.

[0036] In this process, defects in the semiconductor channel layer material dominate the recombination process of charge carriers in the semiconductor, forming defect energy levels in the band gap. At lower temperatures, photogenerated charge carriers (electrons and holes) are trapped in trapped states and cannot participate in conduction. After being trapped, the charge carriers need to overcome the energy barrier through thermal excitation to be released, a process that follows the Boltzmann distribution. As the temperature increases, the thermal excitation energy overcomes the trap binding energy, allowing the charge carriers trapped in the trapped states to be released as free charge carriers and participate in conduction, thus generating photocurrent characteristics that increase with increasing temperature.

[0037] The power module is used to provide a stable operating voltage for the entire system.

[0038] The microcontroller unit is connected to other modules to receive and analyze the electrical signals output by the photodetector and determine whether the set alarm threshold has been reached. This allows the microcontroller to control other modules to take corresponding actions, such as sounding and lighting alarms, activating relays, and transmitting data to the mobile terminal via a wireless transmission module.

[0039] An audible and visual alarm device is used to issue an alarm signal when the temperature of the detection equipment reaches a preset overload warning threshold.

[0040] The relay control unit is used to automatically disconnect the power supply when the equipment temperature rises further to a severe overload or fire threshold, to prevent the accident from escalating.

[0041] The wireless transmission module is used to transmit device status information to a remote terminal or IoT platform in real time, enabling remote monitoring and alarm.

[0042] Example 4: The working method of an early warning IoT system based on a temperature-enhanced photodetector includes the following steps: Step 1, based on Nb3Se 12 The photodetector of 1-nanowires collects the temperature and light intensity in the target area in real time and sends a current signal to the control unit.

[0043] Step 2: The control unit compares the current signal with a preset threshold. When the current signal is greater than the preset threshold, the control unit generates an alarm signal and a relay control signal. The alarm signal is sent to the audible and visual alarm device, and the relay control signal is sent to the relay control unit. The alarm signal and the relay control signal are then sent together to the wireless transmission module.

[0044] Step 3: The audible and visual alarm device will activate the audible and visual alarm based on the received alarm signal.

[0045] Step four: The relay control unit shuts off the power supply based on the received relay control signal.

[0046] Step 5: The wireless transmission module is used to send both alarm signals and relay control signals to the host computer.

[0047] Step six: The host computer performs remote monitoring and display based on the received alarm signals and relay control signals.

[0048] The semiconductor material Nb3Se used in this invention 12 I. A simplified synthetic method was used to efficiently obtain one-dimensional nanowire structures. These structures are small in size, easy to integrate, suitable for monitoring overheating conditions in microelectronic devices, and provide a material basis for the integrated development of artificial intelligence systems. This invention is based on Nb3Se. 12 The photothermal synergistic effect of I-materials has led to the construction of a temperature-enhanced photodetector. Compared to traditional early warning systems that rely on thermistors, infrared, or smoke sensors, this device possesses multi-physical quantity coupling sensing capabilities, overcoming the problems of poor stability and response lag at high temperatures. The proposed detector maintains stable performance in high-temperature environments, and its photoelectric response enhances with increasing temperature. It is suitable for rapid early warning of risks such as overload, overheating, and fire in electronic equipment, and is particularly well-suited for high-reliability applications such as smart homes and industrial IoT.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for fabricating a temperature-enhanced photodetector, characterized in that, Includes the following steps: According to Nb3Se 12 The stoichiometric ratio of each element in I is used to weigh Nb powder, Se powder and I crystal with a purity of 99.999%, and the Nb powder, Se powder and I crystal are synthesized into a semiconductor material by chemical vapor transport method. Photoresist is spin-coated onto a blank substrate, and a hollow interdigitated electrode pattern is photolithographically formed on the photoresist. A substrate with an interdigitated electrode structure having a source and a drain is fabricated based on the interdigitated electrode pattern. Semiconductor material is placed in anhydrous ethanol and subjected to ultrasonic treatment to separate the semiconductor material into quasi-one-dimensional nanowire material structures. Anhydrous ethanol dispersion of the quasi-one-dimensional nanowire material structures is dropped onto a substrate with a prepared interdigitated electrode structure and allowed to dry naturally. The dried substrate is then subjected to annealing post-treatment to obtain a temperature-enhanced photodetector.

2. The method for fabricating a temperature-enhanced photodetector according to claim 1, characterized in that, When fabricating a substrate with source and drain electrode structures based on the interdigitated electrode pattern, resistive thermal evaporation technology and a lift-off process are used.

3. The method for fabricating a temperature-enhanced photodetector according to claim 1, characterized in that, When annealing the dried substrate, the annealing temperature is 120°C and the annealing time is 6 hours.

4. The method for fabricating a temperature-enhanced photodetector according to claim 1, characterized in that, I crystals were used as the transport agent, with a concentration of 2 mg / cm³. 3 .

5. The method for fabricating a temperature-enhanced photodetector according to claim 1, characterized in that, Nb3Se 12 The Se vacancy concentration in I nanowires is 5%-10%.

6. The method for fabricating a temperature-enhanced photodetector according to claim 1, characterized in that, The channel length of the interdigitated electrode is 30 µm and the channel width is 5 mm.

7. An early warning Internet of Things system based on a temperature-enhanced photodetector, characterized in that, include: Temperature-enhanced photodetectors, employing Nb3Se... 12 A photodetector made of 1 nanowires is used to receive temperature and light intensity output current signals and send them to the control unit. The microcontroller unit is used to compare the current signal with a preset threshold and generate a control signal, which is then sent to the audible and visual alarm device, the relay control unit, and the wireless transmission module. An audible and visual alarm device is used to trigger an alarm based on received control signals. The relay control unit is used to shut off the power supply based on the received control signal; The wireless transmission module is used to send control information to the host computer.

8. The early warning IoT system based on a temperature-enhanced photodetector according to claim 7, characterized in that, Based on Nb3Se 12 The 1-nanowire photodetector includes a substrate, a dielectric layer disposed on the substrate, a source electrode and a drain electrode disposed on the dielectric layer, the source electrode and the drain electrode being distributed in the form of interdigitated electrodes, and a semiconductor channel layer between the source electrode and the drain electrode.

9. A working method for an early warning Internet of Things system based on a temperature-enhanced photodetector, characterized in that, Includes the following steps: Based on Nb3Se 12 The photodetector of 1 nanowires collects the temperature and light intensity in the target area in real time and sends a current signal to the control unit. The control unit compares the current signal with a preset threshold. When the current signal is greater than the preset threshold, the control unit generates an alarm signal and a relay control signal. The alarm signal is sent to the audible and visual alarm device, the relay control signal is sent to the relay control unit, and the alarm signal and the relay control signal are sent together to the wireless transmission module. The audible and visual alarm device will trigger an audible and visual alarm based on the received alarm signal; The relay control unit controls the power supply to be turned off based on the received relay control signal; The wireless transmission module is used to send alarm signals and relay control signals to the host computer.

10. The operating method of the early warning IoT system based on a temperature-enhanced photodetector according to claim 9, characterized in that, The host computer performs remote monitoring and display based on the received alarm signals and relay control signals.

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