Self-energized avalanche photoelectric detection system and preparation method thereof

Abstract

The invention discloses a self-powered avalanche photoelectric detection system and a preparation method, and relates to the technical field of passive optical fiber leakage monitoring, the self-powered avalanche photoelectric detection system comprises a collection module which comprises a receiving antenna, a rectification module and a power management module, the receiving antenna is connected with the rectification module, and the power management module is connected with the output end of the rectification module; the avalanche photodetector includes a heterojunction composed of a first semiconductor material layer and a second semiconductor material layer. According to the invention, redundant microwave energy in the environment is absorbed to provide a stable power supply for the avalanche photodetector, so that long-time and low-power-consumption efficient work is realized. Meanwhile, the avalanche photoelectric detector operates in a critical state close to the avalanche voltage, can perform high-sensitivity detection and multiplication amplification on weak optical signals, and ensures accurate capture and transmission of the signals. According to the invention, the change of the optical signal can be responded in real time within the nanosecond level, and the method is suitable for application scenarios requiring real-time monitoring and accurate measurement.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of passive optical fiber leakage monitoring, and in particular to a self-powered avalanche photodetector system and a preparation method thereof. BACKGROUND

[0002] The avalanche photodetector plays an important role in high-precision detection fields such as laser radar, spectral analysis and optical communication due to its high gain and low noise. However, the dependence of the avalanche photodetector on continuous and stable power supply has become a major bottleneck for its application, especially in complex environments such as unmanned aerial vehicles, satellites and remote monitoring. Traditional wired power supply methods are difficult to meet the long-term stable operation requirements. To solve this problem, microwave wireless energy transmission technology provides an efficient and non-contact energy supply solution. This solution not only breaks through the spatial limitations of traditional power supply methods, but also significantly improves the flexibility and adaptability of the system, especially for scenarios that require high-precision detection and long-term continuous operation. By combining microwave wireless energy transmission technology with avalanche photodetectors, not only can the power supply problem be effectively solved, but also new possibilities are provided for the widespread application of avalanche photodetectors in the Internet of Things and remote monitoring systems. SUMMARY

[0003] Therefore, the technical problem to be solved by the present application is that the traditional wired power supply method is difficult to meet the long-term stable operation requirements of the avalanche photodetector.

[0004] The above technical problem is solved by the following technical scheme:

[0005] The present application provides a self-powered avalanche photodetector system, which comprises a collection module and an avalanche photodetector.

[0006] In a preferred embodiment of the self-powered avalanche photodetector system according to the present application, the collection module comprises a receiving antenna, a rectification module and a power management module, the receiving antenna and the rectification module are connected, and the power management module and the output end of the rectification module are connected.

[0007] The avalanche photodetector is connected to the collection module and comprises a heterojunction composed of a first semiconductor material layer and a second semiconductor material layer.

[0008] In a preferred embodiment of the self-powered avalanche photodetector system according to the present application, the collection module further comprises a power capacitor, and the power capacitor and the input end of the power management module are connected in parallel.

[0009] In a preferred embodiment of the self-powered avalanche photoelectric detection system of the present invention: the power management module includes a first boost converter and a second boost converter, the first boost converter and the second boost converter are connected in series, and the output terminal of the first boost converter is electrically connected to the input terminal of the second boost converter.

[0010] In a preferred embodiment of the self-powered avalanche photodetector system of the present invention: the first booster is used to boost the low voltage output by the rectifier module to an intermediate voltage; the second booster is used to boost the intermediate voltage to the operating voltage required by the avalanche photodetector.

[0011] In a preferred embodiment of the self-powered avalanche photoelectric detection system of the present invention: the intermediate voltage is 3.3V and the operating voltage is 20V.

[0012] In a preferred embodiment of the self-powered avalanche photoelectric detection system of the present invention: the first semiconductor material layer is a p-type semiconductor substrate; the second semiconductor material layer is a tungsten diselenide sheet.

[0013] In a preferred embodiment of the self-powered avalanche photoelectric detection system of the present invention: the p-type semiconductor substrate is p-type germanium.

[0014] In a preferred embodiment of the self-powered avalanche photoelectric detection system of the present invention: the doping element of the p-type semiconductor substrate is boron.

[0015] The present invention also proposes a method for preparing a self-powered avalanche photoelectric detection system, which includes preparing a collection module, an avalanche photoelectric detector, and connecting the collection module and the avalanche photoelectric detector.

[0016] In a preferred embodiment of the preparation method of the self-powered avalanche photoelectric detection system of the present invention: a collection module is prepared, a receiving antenna is electrically connected to a rectifier module, and the output terminal of the rectifier module is electrically connected to the input terminal of a power management module.

[0017] To fabricate an avalanche photodetector, an insulating layer is formed on a substrate serving as a first semiconductor material layer, a window is opened in the insulating layer to expose the first semiconductor material layer, and a thin sheet serving as a second semiconductor material layer is transferred into the window to form a heterojunction.

[0018] The output terminal of the power management module is electrically connected to the avalanche photodetector, and the collection module is used to power the avalanche photodetector.

[0019] In a preferred embodiment of the preparation method of the self-powered avalanche photoelectric detection system of the present invention: a power capacitor is connected in parallel between the output terminal of the rectifier module and the input terminal of the power management module.

[0020] The beneficial effects of this invention are as follows: by absorbing excess microwave energy from the environment to provide a stable power supply for the avalanche photodetector, it avoids dependence on traditional batteries or external power sources, thereby achieving long-term, low-power, and highly efficient operation. Simultaneously, the avalanche photodetector operates at a critical state close to the avalanche voltage, enabling highly sensitive detection and amplification of weak light signals, ensuring accurate signal capture and transmission. This invention has an extremely fast response time, capable of responding to changes in light signals in real time at the nanosecond level, making it suitable for applications requiring real-time monitoring and precise measurement. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention.

[0022] Figure 1 An energy flow diagram is shown;

[0023] Figure 2 A schematic diagram of the microstructure of an avalanche photodetector as observed under a microscope is shown.

[0024] Figure 3 The dark current-voltage (IV) curves of the avalanche photodetector on the drain side are shown, as well as the IV curves under illumination at 532 nm and 1550 nm.

[0025] Figure 4 The rise and fall times of the avalanche photodetector under 532nm pulsed light are shown.

[0026] Figure 5 The rise and fall times of the avalanche photodetector under 1550nm pulsed light are shown. Detailed Implementation

[0027] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0028] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0029] Example 1, referring toFigure 1 and Figure 2 This embodiment provides a self-powered avalanche photoelectric detection system, including an avalanche photoelectric detector 2 and a collection module 1 that powers the avalanche photoelectric detector 2.

[0030] Specifically, the collection module 1 captures microwave energy from the environment and boosts it twice to convert the captured energy into a stable DC operating voltage required by the avalanche photodetector 2.

[0031] The collection module 1 includes a receiving antenna 11, a rectifier module 12, and a power management module 13. The receiving antenna 11 and the rectifier module 12 are connected, and the power management module 13 is connected to the output of the rectifier module 12. The receiving antenna 11 is the energy input of the system and is responsible for capturing microwaves from space. The rectifier module 12 is responsible for converting the high-frequency AC signal captured by the antenna into DC power. The power management module 13 processes the energy and converts the unstable DC power into a stable voltage that can be used by subsequent devices.

[0032] The avalanche photodetector 2 is connected to the collection module 1 and includes a heterojunction composed of a first semiconductor material layer 21 and a second semiconductor material layer 22.

[0033] The first semiconductor material layer 21 is p-type germanium, and the second semiconductor material layer 22 is tungsten diselenide. The two layers are in contact to form a heterojunction, which is the basis for realizing photoelectric conversion and avalanche multiplication effect.

[0034] When the system is in operation, the receiving antenna 11 first captures microwave energy from the environment in the 5.5GHz to 6.1GHz frequency band. Subsequently, the microwave energy is transmitted to the rectifier module 12 and converted into low-voltage DC power. This low-voltage DC power is used to charge a capacitor connected in parallel with the input of the power management module 13, achieving initial energy accumulation. When sufficient energy is accumulated, the first boost converter 131 in the power management module 13 is activated, boosting the low voltage provided by the supercapacitor to a stable intermediate voltage of 3.3V. Then, the second boost converter 132 converts this intermediate voltage... The voltage is further increased to the stable high-voltage bias of 20V required for the operation of the avalanche photodetector 2. This 20V high-voltage bias is applied to the avalanche photodetector 2, putting it in a highly sensitive avalanche critical standby state. When a weak light signal is incident on the heterojunction composed of the first semiconductor material layer 21 and the second semiconductor material layer 22, the avalanche multiplication effect is triggered, generating a significantly amplified current signal. This amplified current signal can be captured by subsequent circuits to trigger alarms or report data, thereby realizing the fiber optic leakage monitoring function without an external power supply.

[0035] The externally deployed collection module 1 continuously captures microwave radiation present in the environment, including but not limited to base stations and power equipment, and efficiently converts it into stable electrical energy, which is then rectified and filtered to power the entire system. The avalanche photodetector 2 is maintained at a critical state close to its avalanche breakdown voltage, in a highly sensitive monitoring mode that can be triggered at any time.

[0036] When there is mechanical disturbance, loose connection, or physical damage to the fiber optic connector, patch panel, or access point, a very small amount of optical signal may leak to the outside. Even with extremely weak leakage, the avalanche photodetector 2 can respond to the incident photon within nanoseconds. The small number of electrons excited by the photon triggers the avalanche multiplication process in a strong electric field, and the output current increases rapidly, allowing the leakage signal, which would otherwise be difficult to detect by traditional optoelectronic devices, to be reliably amplified.

[0037] The pulse signal output by the avalanche photodetector 2 can trigger LED flashing or be reported to a remote system through a simple circuit, forming a passive, maintenance-free local alarm mechanism. Since this system is powered entirely by ambient microwave energy, it does not require traditional batteries or mains power connections, making it suitable for locations with limited power supply and space constraints, such as communication base stations, outdoor optical junction boxes, and rail transit communication wells. It is especially suitable for unattended nodes deployed in large-scale distributed communication networks.

[0038] By integrating the high-gain optical detection capability of the avalanche photodetector 2 with the collection module 1, this invention provides a highly reliable, easy-to-deploy, and long-term stable optical fiber leakage detection solution, which can significantly improve the maintainability and fault response efficiency of communication networks.

[0039] Example 2, refer to Figures 1 to 5 This embodiment, based on the previous embodiment, provides a self-powered avalanche photoelectric detection system, including an avalanche photoelectric detector 2 and a collection module 1 that powers the avalanche photoelectric detector 2.

[0040] Specifically, the collection module 1 includes a receiving antenna 11, a rectifier module 12, and a power management module 13. The receiving antenna 11 is connected to the rectifier module 12, and the power management module 13 is connected to the output of the rectifier module 12.

[0041] The energy collection module 1 is responsible for energy collection and management, while the avalanche photodetector 2 is responsible for photoelectric detection.

[0042] The receiving antenna 11 is responsible for capturing microwaves in a specific frequency band from space, operating at frequencies from 5.5 GHz to 6.1 GHz. It is fabricated using a composite material of PCB substrate and ceramic material, and is back-fed. The antenna module has a gain performance of 0-1 dBi and a half-power beamwidth greater than 50°. The initial length and width of the rectangular antenna were calculated based on the frequency and basic parameters and simulated. The overall size was optimized to 35 mm × 35 mm to achieve efficient reception of high-frequency signals.

[0043] The rectifier module 12 is a single-parallel microwave rectifier operating at frequencies from 5.5 GHz to 6.1 GHz, achieving a rectification efficiency exceeding 50% under input power conditions ranging from 0 dBm to 15 dBm. The rectifier achieves impedance matching through lumped components, uses a Teflon high-frequency board as the PCB substrate, and is directly integrated onto the back of the antenna module for a compact design.

[0044] In power management module 13, the LTC3108 DC-DC power management chip serves as the first boost converter 131, and the MT3608 DC-DC power management chip serves as the second boost converter 132. The LTC3108 requires a 1F supercapacitor connected in parallel at its input to ensure sufficient startup energy is stored at the low voltage (e.g., 0.3V) output from the rectifier module. This chip can boost the low voltage to 3.3V. The LTC3108 DC-DC power management chip is connected to the MT3608 DC-DC power management chip. This chip can boost the 3.3V to the 20V required by the avalanche photodetector.

[0045] Specifically, the collection module 1 also includes a power capacitor 14, which is connected in parallel with the input terminal of the power management module 13. The power capacitor 14 is also connected in parallel with the avalanche photodetector 2. The power capacitor 14 stores the electrical energy converted by the rectifier module 12 and output by the power management module 13, and provides the energy required for the operation of the avalanche photodetector 2, ensuring stable operation of the system under intermittent energy input conditions.

[0046] The avalanche photodetector 2 is connected to the collection module 1 and includes a heterojunction composed of a first semiconductor material layer 21 and a second semiconductor material layer 22.

[0047] The first semiconductor material layer 21 is p-type germanium as a substrate, and the second semiconductor material layer 22 is tungsten diselenide. The two layers are in contact to form a heterojunction, which is the basis for realizing photoelectric conversion and avalanche multiplication effect.

[0048] The first semiconductor material layer 21 is a p-type semiconductor substrate; the second semiconductor material layer 22 is tungsten diselenide, which is responsive to visible light and can undergo an avalanche effect under high voltage. It is a two-dimensional material sheet that can generate an avalanche multiplication effect.

[0049] The doping element for p-type semiconductor substrates is boron, but gallium or indium can also be used to generate holes.

[0050] When the system is working, the receiving antenna 11 first captures microwave energy from the environment in the 5.5GHz to 6.1GHz frequency band. The microwave energy is then transmitted to the rectifier module 12 and converted into low-voltage DC power. This low-voltage DC power is used to charge a power capacitor 14 connected in parallel with the input of the power management module 13, accumulating initial energy. When the power capacitor 14 has accumulated sufficient energy, the first boost converter 131 in the power management module 13 is activated, boosting the low voltage provided by the supercapacitor to a stable intermediate voltage of 3.3V. Then, the second boost converter 13... 2. The intermediate voltage is further increased to the stable high-voltage bias of 20V required for the operation of the avalanche photodetector 2. The 20V high-voltage bias is applied to the avalanche photodetector 2, putting it in a highly sensitive avalanche critical standby state. When a weak light signal is incident on the heterojunction composed of the first semiconductor material layer 21 and the second semiconductor material layer 22, the avalanche multiplication effect is triggered, generating a significantly amplified current signal. This amplified current signal can be captured by subsequent circuits to trigger an alarm or report data, thereby realizing the fiber optic leakage monitoring function without an external power supply.

[0051] Example 3, referring to Figure 1 This embodiment provides a method for fabricating a self-powered avalanche photoelectric detection system, including fabricating a collection module and an avalanche photoelectric detector, and connecting the collection module and the avalanche photoelectric detector.

[0052] The preparation of the collection module includes the following steps:

[0053] S1.1 is a receiving antenna designed for operation at frequencies from 5.5 GHz to 6.1 GHz. It is fabricated using a composite material of PCB substrate and ceramic material, and is back-fed. The antenna module has a gain of 0-1 dBi, a half-power beamwidth greater than 50°, and an overall size optimized to 35 mm × 35 mm to achieve efficient reception of high-frequency signals.

[0054] S1.2 is a single-parallel microwave rectifier designed for operating frequencies from 5.5 GHz to 6.1 GHz, achieving a rectification efficiency exceeding 50% under input power conditions ranging from 0 dBm to 15 dBm. The rectifier achieves impedance matching through lumped components, uses a Teflon high-frequency board as the PCB substrate, and is directly integrated onto the back of the antenna module for a compact design.

[0055] S1.3 connects the output of the rectifier module to the LTC3108 DC-DC power management chip as the first-stage boost circuit. A 1F supercapacitor needs to be connected in parallel to the input of the LTC3108 to ensure sufficient startup energy is stored at the low voltage output of the rectifier module, such as 0.3V. This chip can boost the low voltage to 3.3V.

[0056] S1.4 Connect the LTC3108 DC-DC power management chip to the MT3608 DC-DC power management chip. This chip can boost the 3.3V to the 20V required by the avalanche photodetector;

[0057] In step S1.5, the power capacitor is connected in series with the power management chip and in parallel with the avalanche photodetector. The power capacitor stores the electrical energy converted by the rectifier module and output from the power management module, and provides the energy required for the avalanche photodetector to operate, ensuring stable system operation under intermittent energy input conditions.

[0058] The fabrication of an avalanche photodetector includes the following steps:

[0059] S2.1, A SiO2 thin film is deposited on a p-type Ge substrate using plasma-enhanced chemical vapor deposition.

[0060] S2.2, a rectangular germanium window with a size of 30nm*50nm is opened on the SiO2 layer using ultraviolet lithography and reactive ion etching technology. The purpose is to allow WSe2 and Ge to contact each other during subsequent material transfer.

[0061] S2.3, Ni or Au is deposited as the metal electrode using electron beam evaporation technology. Ni has better adhesion, while Au has better conductivity; the Ni / Au combination is an ideal metal electrode combination. The electrode is isolated from the Ge substrate by the deposited SiO2 layer.

[0062] S2.4, mechanically peeling WSe2 or other flakes from the crystal onto a polydimethylsiloxane substrate, and then transferring them onto a patterned germanium substrate, wherein WSe2 may be replaced with a compound that is responsive to visible light and can undergo an avalanche effect under high voltage;

[0063] Preferably, the thicknesses of the Ni / Au metal electrodes are 5 nm and 50 nm, respectively.

[0064] Preferably, the thickness of the SiO2 thin film is 100 nm.

[0065] Preferably, the n-Ge material has a crystal orientation of 100, a resistivity of less than 10 Ω·cm, and a thickness of 500-625 μm.

[0066] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A self-powered avalanche photoelectric detection system, characterized in that: include, Avalanche photodetector (2); The collection module (1), connected to the avalanche photodetector (2), includes a receiving antenna (11), a rectifier module (12), and a power management module (13) connected in sequence. The receiving antenna (11) is used to receive microwave energy in the environment and transmit it to the rectifier module (12). The rectifier module (12) converts the microwave energy transmitted by the receiving antenna (11) into low-voltage DC power and sends it to the power management module (13). The power management module (13) is used to convert the low-voltage DC power into a stable high-voltage bias required for the operation of the avalanche photodetector (2) through a two-stage boost process. The power management module (13) includes a first boost converter (131) and a second boost converter (132), which are connected in series. The output terminal of the first boost converter (131) is electrically connected to the input terminal of the second boost converter (132).

2. The self-powered avalanche photoelectric detection system according to claim 1, characterized in that: The collection module (1) also includes a power capacitor (14), which is connected in parallel with the input terminal of the power management module (13).

3. The self-powered avalanche photoelectric detection system according to claim 2, characterized in that: The avalanche photodetector (2) is connected to the collection module (1) and includes a heterojunction composed of a first semiconductor material layer (21) and a second semiconductor material layer (22).

4. The self-powered avalanche photoelectric detection system according to claim 3, characterized in that: The first boost unit (131) is used to boost the low voltage output by the rectifier module (12) to an intermediate voltage; the second boost unit (132) is used to boost the intermediate voltage to the operating voltage required by the avalanche photodetector (2).

5. The self-powered avalanche photoelectric detection system according to claim 4, characterized in that: The intermediate voltage is 3.3V, and the operating voltage is 20V.

6. The self-powered avalanche photoelectric detection system according to claim 1, characterized in that: The first semiconductor material layer (21) is a p-type semiconductor substrate; the second semiconductor material layer (22) is tungsten diselenide.

7. The self-powered avalanche photoelectric detection system according to claim 6, characterized in that: The p-type semiconductor substrate is p-type germanium.

8. The self-powered avalanche photoelectric detection system according to claim 7, characterized in that: The p-type semiconductor substrate is doped with boron.

9. A method for fabricating a self-powered avalanche photoelectric detection system, characterized in that: A collection module is prepared by electrically connecting a receiving antenna to a rectifier module and electrically connecting the output terminal of the rectifier module to the input terminal of a power management module. To fabricate an avalanche photodetector, an insulating layer is formed on a substrate serving as a first semiconductor material layer, a window is opened in the insulating layer to expose the first semiconductor material layer, and a thin sheet serving as a second semiconductor material layer is transferred into the window to form a heterojunction. The output terminal of the power management module is electrically connected to the avalanche photodetector, and the collection module is used to power the avalanche photodetector.

10. The method for preparing the self-powered avalanche photoelectric detection system according to claim 9, characterized in that: A power capacitor is connected in parallel between the output terminal of the rectifier module and the input terminal of the power management module.

Images