A multifunctional optical fiber electronic system based on D-shaped optical fiber and a preparation method thereof

Abstract

This invention discloses a multifunctional fiber optic electronic system based on D-shaped optical fiber and its fabrication method, belonging to the technical field of fiber optic optoelectronic integration and information functional devices. The system includes a D-shaped optical fiber and various heterogeneous micro / nano devices integrated in situ on the polished side surface of the D-shaped optical fiber. The D-shaped optical fiber is used for optical signal transmission and also serves as an integration substrate. The flat, processable area formed by polishing its side surface is called the polished side surface, which is used to integrate various heterogeneous micro / nano devices. These heterogeneous micro / nano devices are used to realize in-situ signal detection, logic processing, temperature self-monitoring, and wireless energy and signal interaction functions. This overcomes the losses and complexity caused by the traditional "fiber-chip" discrete architecture, significantly improving system integration, energy efficiency, and reliability.

Description

Technical Field

[0001] This invention belongs to the field of fiber optic optoelectronic integration and information functional device technology, and particularly relates to a multifunctional fiber optic electronic system based on D-type optical fiber and its fabrication method. Background Technology

[0002] Optical fiber, with its ultra-low transmission loss and high bandwidth, has long served as the core of global information transmission infrastructure. However, traditional optical fibers primarily function as passive transmission media, responsible only for optical signal transmission, and cannot perform active signal modulation, detection, or logic processing within the fiber itself. In existing optical fiber communication systems, signals rely on external chips to complete electro-optical and optical-electrical conversions, leading to increased coupling loss, higher system complexity, and increased energy consumption. This becomes an energy efficiency bottleneck in scenarios such as data centers and high-performance computing.

[0003] Existing technologies have attempted to extend the functionality of optical fibers by integrating gratings, photosensitive coatings, or two-dimensional materials onto the fiber surface, but most remain limited to the detection of single physical quantities or the functional extension of single devices. Current research has not yet established an architecture capable of simultaneously realizing multifunctional collaborative operations such as logic operations, photoelectric conversion, optically controlled logic response, wireless energy and signal interaction, and temperature monitoring on a single optical fiber. Meanwhile, a systematic solution remains lacking for how to achieve high-density in-situ integration of different types of micro- and nano-devices, while ensuring process compatibility between devices and efficient coupling with the evanescent field of optical fibers.

[0004] Therefore, there is an urgent need for a multifunctional, highly integrated, and technologically feasible fiber optic electronic system to break through the limitations of traditional passive fiber optic transmission, realize active signal processing and energy autonomy in fiber optics, and provide a technical foundation for intelligent fiber optic networks and system-level fiber optic function expansion. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a multifunctional fiber optic electronic system based on D-type optical fiber and its fabrication method, thereby overcoming the losses and complexity caused by the traditional "fiber-chip" separation architecture and significantly improving system integration, energy efficiency, and reliability.

[0006] The technical solution of this invention is as follows:

[0007] On one hand, the present invention provides a multifunctional fiber optic electronic system based on D-shaped optical fiber, including D-shaped optical fiber and various heterogeneous micro-nano devices in situ integrated on the side polished surface of D-shaped optical fiber; the D-shaped optical fiber is used for optical signal transmission and also serves as an integration substrate, and the flat, processable area formed by polishing its side is called the side polished surface, which is used to integrate various heterogeneous micro-nano devices; the various heterogeneous micro-nano devices are used to realize in-situ signal detection, logic processing, temperature self-monitoring, and wireless energy and signal interaction functions of optical fiber.

[0008] Furthermore, the heterogeneous micro / nano device includes a carbon-based logic circuit unit, a phototransistor unit, a light-controlled logic unit, a wireless communication and energy unit, and a temperature sensing unit;

[0009] The phototransistor unit is used to convert optical signals into electrical signals, which serve as inputs to the carbon-based logic circuit unit.

[0010] The carbon-based logic circuit unit is used to generate a periodic oscillation signal and perform digital logic operations on the input electrical signal based on the generated periodic oscillation signal to obtain the logic operation result; the generated periodic oscillation signal and the logic operation result are input to the wireless communication and energy unit;

[0011] The optical control logic unit is used to realize the inverse mapping from optical signal to voltage logic signal, and the output voltage logic signal is used as the input of wireless communication and energy unit; the voltage logic signal corresponds to the logic state change of optical signal, and realizes in-situ electrical reading of optical signal transmitted in optical fiber without interrupting optical fiber transmission.

[0012] The temperature sensing unit is used to realize in-situ temperature monitoring along the optical fiber and obtain temperature monitoring results.

[0013] The wireless communication and energy unit, as a receiver, supplies power to the carbon-based logic circuit unit, phototransistor unit, light-controlled logic unit, and temperature sensing unit by receiving near-field wireless energy generated externally; and as a transmitter, it realizes the wireless transmission of periodic oscillation signals, logic operation results, and voltage logic signals.

[0014] Furthermore, the phototransistor unit uses a composite film composed of a semiconductor-type single-walled carbon nanotube thin film and a CsPbBr3 quantum dot thin film as the channel material to form a buried gate phototransistor. The buried gate phototransistor can operate in two optical coupling modes: external light source detection mode and waveguide evanescent field detection mode. In the external light source detection mode, external incident light directly irradiates the channel region of the buried gate phototransistor to generate a photoelectric response, converting the optical signal into an electrical signal. In the waveguide evanescent field detection mode, the optical signal of the guided wave mode propagating along the optical fiber forms an evanescent field on the side polished surface and couples with the channel to generate a photoelectric response, converting the optical signal into an electrical signal.

[0015] Furthermore, the carbon-based logic circuit unit is a logic circuit composed of several thin-film transistors, inverters, and ring oscillators; the thin-film transistors are thin-film transistors with semiconductor single-walled carbon nanotubes as channel materials, serving as basic active devices to realize electrical switching characteristics; the inverters are used to realize logic inversion functions; and the ring oscillators are used to generate periodic oscillation signals, serving as a local clock source or directly outputting to the wireless communication and power unit.

[0016] Furthermore, the optical control logic unit is an inverter consisting of a load transistor and a drive transistor. The gate and source of the load transistor are shorted to form a constant current source-type load. The channel surface of the drive transistor is modified with CsPbBr3 quantum dots to regulate the threshold voltage, so that the optical signal coupled to the channel region can directly control the conduction state of the drive transistor, thereby causing a change in the output voltage of the inverter. Specifically, the logic decision level is set according to the threshold voltage, so that the output is low when there is light input and high when there is no light input, realizing the inverse mapping of optical signal to voltage logic signal.

[0017] Furthermore, the temperature sensing unit is based on a Ti / Au nanoelectrode and coated with a PMMA thin film to form a metal-dielectric interface structure. The Ti / Au nanoelectrode is coupled with the evanescent field of the fiber core to excite surface plasmon resonance. The PMMA thin film enhances the response of the interface refractive index to the surface plasmon resonance and provides mechanical encapsulation and protection. The in-situ temperature monitoring function along the fiber is realized by monitoring the drift of the transmission spectrum absorption peak with the change of ambient temperature.

[0018] Furthermore, the wireless communication and energy unit is a multilayer spiral microcoil constructed by alternately depositing Ti / Au metal layers and Al2O3 dielectric layers on the polished surface of the optical fiber side.

[0019] On the other hand, the present invention also provides a method for fabricating a multifunctional fiber optic electronic system based on D-type optical fiber, comprising the following specific steps:

[0020] Step 1: Preprocess the D-type optical fiber to obtain the preprocessed D-type optical fiber;

[0021] Specifically, the D-type optical fiber is immersed in electronic-grade acetone for more than 20 minutes to remove the polymer resin coating layer on its surface; then, the D-type optical fiber is thoroughly rinsed with electronic-grade isopropanol and completely dried under an electronic-grade nitrogen gas flow; the D-type optical fiber is transferred and fixed to the surface of a silicon wafer pre-coated with positive photoresist S1813; the positive photoresist is spin-coated at a speed of 300-1000 rpm for 3-10 seconds to form a thin film, and then cured on a hot plate at 150-240℃ for 1-3 hours;

[0022] Step 2: Fabricate various heterogeneous micro / nano devices on D-type optical fibers to obtain a complete multifunctional fiber optic electronic system based on D-type optical fibers;

[0023] (a) The fabrication methods for thin-film transistors, inverters, and ring oscillators in carbon-based logic circuit units are as follows:

[0024] First, a gate electrode is fabricated on the side-polished surface of a D-shaped optical fiber using maskless photolithography, electron beam evaporation, and lift-off processes. The gate electrode is a Ti / Au bilayer metal structure, with a Ti layer thickness of 3-10 nm and an Au layer thickness of 30-100 nm. Subsequently, an Al₂O₃ dielectric layer of 30-100 nm thickness is deposited at 100-200 °C using trimethylaluminum and water as precursors. Electrode contact holes are formed on the Al₂O₃ dielectric layer by reactive ion etching. Then, Ti / Au source and drain electrodes are fabricated on the Al₂O₃ dielectric layer using the same maskless photolithography-electron beam evaporation-lift-off process as the gate electrode. The surface of the D-shaped optical fiber is then functionalized with hexamethyldisilazane as a single layer. Finally, the D-shaped optical fiber is immersed in a carbon nanotube solution and held at 25-60 °C for 2-12 hours. h, carbon nanotubes are uniformly attached to the surface of D-type optical fiber by wet self-assembly; the carbon nanotube-modified D-type optical fiber is rinsed with toluene and isopropanol in sequence, each step for 3-10 min; finally, the transistor channel range is defined by maskless photolithography and oxygen plasma etching, and finally thin film transistor is obtained; inverters and ring oscillators are fabricated using different layouts according to the same fabrication method as thin film transistors.

[0025] (b) The fabrication method of the phototransistor unit is as follows: A transparent metallic single-walled carbon nanotube film is first transferred as a buried gate electrode on the polished surface of the D-type optical fiber using an imprinting method, and the gate electrode region is defined by maskless photolithography and oxygen plasma etching. A 30-100 nm thick Al2O3 dielectric layer is grown on the D-type optical fiber substrate using atomic layer deposition, and windows are created on the Al2O3 dielectric layer by reactive ion etching. Subsequently, Ti / Au source and drain electrodes are fabricated on the Al2O3 dielectric layer using a maskless photolithography-electron beam evaporation-lifting process, wherein the Ti layer thickness is 3-10 nm and the Au layer thickness is 30-100 nm. A semiconductor single-walled carbon nanotube film is deposited in the channel region between the two electrodes, and the channel range is defined by maskless photolithography and oxygen plasma etching. Finally, a CsPbBr3 quantum dot solution of 10-60 μL is spin-coated at a rotation speed of 300-1000 rpm. s, forming a uniform quantum dot thin layer, to obtain a photosensitive layer composed of a quantum dot-carbon nanotube composite system;

[0026] (c) The method for manufacturing the light-controlled logic unit is as follows: Following the inverter manufacturing method in (a), an inverter is manufactured.

[0027] The gate and source of the load transistor are shorted to form a constant current source load, and the channel surface of the driving transistor is modified with CsPbBr3 quantum dots.

[0028] (d) The fabrication method of wireless communication and energy unit is as follows: Ti / Au electrode is prepared as conductive layer by maskless photolithography-electron beam evaporation-lifting process, wherein the thickness of Ti layer is 3-10 nm and the thickness of Au layer is 30-100 nm. A 30-100 nm thick Al2O3 dielectric layer is deposited by atomic layer deposition, and windows are opened on the dielectric layer by reactive ion etching. The above conductive layer / dielectric layer deposition process is repeated alternately to finally form a layered spiral coil structure consisting of four conductive layers and three dielectric layers.

[0029] (e) The temperature sensing unit is fabricated as follows: a Ti / Au electrode is prepared by a maskless photolithography-electron beam evaporation-exfoliation process and placed on the polished surface of the D-type optical fiber. Then, a polymethyl methacrylate (PMMA) film is spin-coated on the Ti / Au electrode structure at a speed of 1000-2000 rpm for 30-60s to form a uniform coating layer.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1. Achieving multifunctional in-situ integration on the optical fiber body: This invention utilizes the planar machinable interface of D-type optical fiber to directly construct various heterogeneous micro-nano devices such as carbon-based logic circuit units, phototransistor units, optical control logic units, wireless communication and energy units, and temperature sensing units on the polished surface of the optical fiber side. This achieves a compact layout of functional coplanarity, enabling the optical fiber to maintain its optical signal transmission capability while possessing the capabilities of active signal processing, photoelectric conversion, and wireless interaction, significantly improving the integration of the optical fiber system.

[0032] 2. Multimodal operation capability and multi-physics coupling characteristics: The phototransistor unit in this invention supports two modes: external light detection and waveguide evanescent field detection. The system also supports digital logic operation, optical control response, energy coupling and radio frequency transmission, enabling optical signals, electrical signals and wireless energy to achieve coplanar integration and in-situ conversion on a single optical fiber, completing multi-physics coupling and exhibiting composite and flexible operation capabilities.

[0033] 3. High-efficiency coupling and low-loss characteristics: The side-discharge region of the D-type fiber is close to the fiber core, which enables the evanescent field of the guided mode to directly interact with the surface-integrated device in the near field, realizing high-efficiency optical-electric coupling. At the same time, signal reading and processing can be completed without interrupting the optical link transmission, shortening the signal transmission path, reducing latency and system power consumption, thereby providing support for distributed optoelectronic edge computing.

[0034] 4. Wireless communication and power: By integrating a miniature planar coil structure in the side-throw area of ​​the optical fiber, low-frequency radio frequency signal transmission and near-field wireless power transmission functions can be realized, enabling optical fiber nodes to have communication capabilities and contactless power supply capabilities, improving the system deployment flexibility, and making it suitable for distributed optical fiber environments where cabling is difficult.

[0035] 5. Environmental monitoring and adaptability: The temperature sensing structure based on surface plasmon resonance provides real-time temperature monitoring capabilities, enhancing the system's perception of environmental changes; the PMMA thin layer also serves as an encapsulation and protection function, improving the system's mechanical stability.

[0036] 6. High Compatibility and Scalability: This invention employs micro-nano fabrication processes such as maskless photolithography, electron beam evaporation, atomic layer deposition, wet assembly, spin coating, and plasma etching to achieve continuous and controllable fabrication of multiple material systems, including carbon nanotubes, quantum dots, metal electrodes, and dielectric thin layers, on optical fiber substrates. This forms a compact and highly process-compatible heterogeneous integration platform, which can flexibly expand functional modules according to application requirements. Each functional unit is integrated on the polished surface of the optical fiber using compatible processes, resulting in a compact and modular structure that can be flexibly configured according to application needs, providing a feasible technical path for building reconfigurable intelligent optical fiber networks.

[0037] The above technical solution overcomes the limitation of traditional optical fibers, which only have passive transmission functions, and achieves a major breakthrough in the functional integration and systematic application of optical fibers. Attached Figure Description

[0038] Figure 1 This is an optical microscopic image of micro / nano devices integrated on the polished surface of an optical fiber in an embodiment of the present invention (scale bar: 100 μm).

[0039] Figure 2 This is a performance characterization diagram of the fiber-integrated carbon-based logic circuit unit in an embodiment of the present invention;

[0040] Among them, (a) is a scanning electron microscope (SEM) image of carbon nanotube thin film; (b) is the transfer characteristic curve of thin film transistor; (c) is the input-output curve and gain curve of inverter; (d) is the output waveform of 5-stage ring oscillator at supply voltage VDD =−8 V;

[0041] Figure 3 The above is a graph showing the room temperature transfer characteristics of the optical fiber integrated phototransistor unit under different optical power densities in an embodiment of the present invention.

[0042] Among them, (a) is the external illumination detection mode; (b) is the waveguide evanescent field detection mode;

[0043] Figure 4 This is a performance characterization diagram of the optical fiber integrated optical control logic unit in an embodiment of the present invention;

[0044] Among them, (a) is the input-output characteristic curve of the optical control logic unit under light and dark conditions; (b) is the in-situ near-field optical signal decoding performance test of the device;

[0045] Figure 5 This is a performance characterization diagram of the fiber-optic integrated wireless communication and energy unit in an embodiment of the present invention;

[0046] Among them, (a) is the radio frequency signal transmission performance test; (b) is the wireless power transmission performance test.

[0047] Figure 6 This is a performance characterization diagram of the fiber-optic integrated temperature sensing unit in an embodiment of the present invention;

[0048] Among them, (a) is the transmission spectrum (400-1000 nm) of the fiber optic electronic system in the range of 20-90℃; (b) is the relationship between the wavelength of the surface plasmon valley and temperature. Detailed Implementation

[0049] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0050] Example 1:

[0051] This invention aims to overcome the limitations of traditional optical fibers, which only possess passive optical transmission capabilities. It proposes a systematic design concept to upgrade optical fibers from "information channels" to "active information nodes." The invention also proposes a multifunctional fiber optic electronic system based on D-type optical fibers, such as... Figure 1 As shown, it includes a D-type optical fiber and a variety of heterogeneous micro-nano devices in situ integrated on the side polished surface of the D-type optical fiber. The heterogeneous micro-nano devices include a carbon-based logic circuit unit, a phototransistor unit, a light-controlled logic unit, a wireless communication and energy unit, and a temperature sensing unit, so as to realize the functions of in-situ signal detection, logic processing, temperature self-monitoring, and wireless energy and signal interaction of the optical fiber.

[0052] The D-type optical fiber is used for optical signal transmission and also serves as an integration substrate. The flat, processable area formed by precision polishing on its side is called the side polishing surface, which is used to integrate various heterogeneous micro-nano devices. This side polishing surface is close to the core of the D-type optical fiber, which maintains low-loss transmission and achieves efficient coupling with various heterogeneous micro-nano devices through the evanescent field of the core, and provides an open processing interface for the integration of heterogeneous micro-nano devices.

[0053] The phototransistor unit is used to convert optical signals into electrical signals, which serve as inputs to the carbon-based logic circuit unit.

[0054] The carbon-based logic circuit unit is used to generate a periodic oscillation signal and perform digital logic operations on the input electrical signal based on the generated periodic oscillation signal to obtain the logic operation result; the generated periodic oscillation signal and the logic operation result are input to the wireless communication and energy unit;

[0055] The optical control logic unit is used to realize the inverse mapping from optical signal to voltage logic signal, and the output voltage logic signal is used as the input of wireless communication and energy unit; the voltage logic signal corresponds to the logic state change of optical signal, and can realize in-situ electrical reading of optical signal transmitted in optical fiber without interrupting optical fiber transmission.

[0056] The temperature sensing unit is used to realize in-situ temperature monitoring along the optical fiber and obtain temperature monitoring results.

[0057] The wireless communication and energy unit, as a receiver, supplies power to the carbon-based logic circuit unit, phototransistor unit, light-controlled logic unit, and temperature sensing unit by receiving near-field wireless energy generated externally; and as a transmitter, it realizes the wireless transmission of periodic oscillation signals, logic operation results, and voltage logic signals.

[0058] The phototransistor unit uses a composite film composed of a semiconductor single-walled carbon nanotube thin film and a CsPbBr3 quantum dot thin film as the channel material to form a buried gate phototransistor. The buried gate phototransistor can operate in two optical coupling modes: external illumination detection mode and waveguide evanescent field detection mode. In the external illumination detection mode, external incident light directly irradiates the channel region of the buried gate phototransistor to generate a photoelectric response, converting the optical signal into an electrical signal. In the waveguide evanescent field detection mode, the optical signal of the guided wave mode propagating along the optical fiber forms an evanescent field on the side polished surface and couples with the channel to generate a photoelectric response, converting the optical signal into an electrical signal. The phototransistor unit in this application exhibits excellent photoelectric performance in both the external illumination detection mode and the waveguide evanescent field detection mode. The generated electrical signal can be directly input to the carbon-based logic circuit on the D-type optical fiber, providing it with a stable photo-to-electric conversion interface.

[0059] The carbon-based logic circuit unit is a logic circuit composed of several thin-film transistors, inverters, and ring oscillators. The thin-film transistors are thin-film transistors with semiconductor single-walled carbon nanotubes as the channel material, serving as basic active devices to achieve controllable electrical switching characteristics. The inverters are built based on thin-film transistors to achieve stable logic inversion. The ring oscillators are used to generate kHz-level periodic oscillation signals, serving as a local clock source or directly outputting to the wireless communication and power unit. In this embodiment, a five-stage ring oscillator is used to verify the continuous operation capability of the fiber optic integrated circuit.

[0060] The optical control logic unit is an inverter consisting of a load transistor and a drive transistor. The gate and source of the load transistor are shorted to form a constant current source type load. The channel surface of the drive transistor is modified with CsPbBr3 quantum dots to regulate the threshold voltage. This allows the optical signal coupled to the channel region to directly control the conduction state of the drive transistor, thereby causing a change in the output voltage of the inverter. Specifically, the logic decision level is set according to the threshold voltage, which can realize a low level output when there is light input and a high level output when there is no light input, thus realizing the inverse mapping from optical signal to voltage logic signal.

[0061] The temperature sensing unit is based on a Ti / Au nanoelectrode with a PMMA thin film covering its surface to form a metal-dielectric interface structure. The Ti / Au nanoelectrode is coupled with the evanescent field of the optical fiber core to excite surface plasmon resonance. The PMMA thin film enhances the response of the interface refractive index to the surface plasmon resonance and provides mechanical encapsulation and protection. By monitoring the drift of the transmission spectrum absorption peak with changes in ambient temperature, in-situ temperature monitoring along the optical fiber in the range of 20-90℃ can be achieved (example sensitivity is about −0.749 nm / ℃, and goodness of fit is about 0.991).

[0062] The wireless communication and energy unit is a multi-layer spiral microcoil constructed by alternately depositing Ti / Au metal layers and Al2O3 dielectric layers on the polished surface of the optical fiber. This multi-layer spiral microcoil can be used as a transmitter for low-frequency radio frequency communication and as a receiver for near-field wireless energy transmission, thereby enabling the fiber optic electronic system to have energy supply and information transmission functions.

[0063] The aforementioned functional units operate independently and stably through coplanar integration, exhibiting excellent process compatibility, mechanical stability, and environmental adaptability. They enable in-situ processing and sensing of fiber optic waveguide signals, as well as wireless transmission of information and energy, thus allowing a single optical fiber to perform multiple functions, including data transmission, environmental sensing, computing, and energy autonomy. In summary, the fiber optic electronic system provided by this invention achieves multifunctional integration on a single optical fiber, demonstrating the technological potential of optical fiber to transform from a passive transmission medium into a multifunctional active information platform.

[0064] Example 2:

[0065] A method for fabricating a multifunctional fiber optic electronic system based on D-type optical fiber includes the following specific steps:

[0066] Step 1: Preprocess the D-type optical fiber to obtain the preprocessed D-type optical fiber;

[0067] Specifically, the D-type optical fiber is immersed in electronic-grade acetone (purity ≥99.5%) for more than 20 minutes to remove the polymer resin coating layer on its surface; then, the D-type optical fiber is thoroughly rinsed with electronic-grade isopropanol (IPA, purity ≥99.5%) and completely dried under an electronic-grade nitrogen gas flow (purity ≥99.99%); after the polymer resin coating layer is removed, the D-type optical fiber is transferred and fixed to the surface of a silicon (100) wafer pre-coated with positive photoresist S1813; the positive photoresist is spin-coated at 300 rpm for 10 seconds to form a uniform thin film, and cured at 150°C for 3 hours to achieve complete curing and cross-linking of the positive photoresist, thereby forming a reliable mechanical adhesion layer, ensuring that the side polished surface of the D-type optical fiber is always horizontally exposed in subsequent processing to meet the requirements of subsequent processes;

[0068] Step 2: Fabricate various heterogeneous micro / nano devices on D-type optical fibers to obtain a complete multifunctional fiber optic electronic system based on D-type optical fibers;

[0069] (a) The fabrication methods for thin-film transistors, inverters, and ring oscillators in carbon-based logic circuit units are as follows:

[0070] First, a gate electrode was fabricated on the side-polished surface of a D-type optical fiber using maskless photolithography, electron beam evaporation (EBV), and lift-off processes. The gate electrode is a Ti / Au bilayer metal structure, with a Ti layer thickness of 5 nm and an Au layer thickness of 50 nm. Subsequently, an Al2O3 dielectric layer with a thickness of 30 nm was deposited at 100-200 °C using trimethylaluminum and water as precursors. Reactive ion etching (RIE) was then performed under the following conditions: CF4 flow rate 50 sccm, cavity pressure 5.0 Pa, RF power 100 W, etching time 10 minutes. In the process of forming electrode contact holes by opening windows in the Al2O3 dielectric layer, Ti / Au source and drain electrodes are prepared on the surface of the Al2O3 dielectric layer using the same maskless photolithography-electron beam evaporation (EBV)-lift process as the gate electrode. To achieve uniform deposition of carbon nanotube network, the surface of D-type optical fiber is first functionalized with hexamethyldisilazane (HMDS). Then, the D-type optical fiber is immersed in carbon nanotube solution and kept at 60℃ for 2 h, so that carbon nanotubes are uniformly attached to the surface of D-type optical fiber by wet self-assembly. The carbon nanotube-modified D-type optical fiber is rinsed with toluene and isopropanol in sequence, each step for 3-10 min. Finally, the transistor channel range is defined by maskless photolithography and oxygen plasma etching (process conditions: O2 flow rate 180-200 sccm, RF power 180-200 W, etching time 30s-2 min), and finally thin film transistor is obtained.

[0071] Inverters and ring oscillators were fabricated using different layouts and the same fabrication methods as thin-film transistors.

[0072] (b) The fabrication method of the phototransistor unit is as follows: a buried gate field-effect transistor structure is selected. Specifically, a transparent metallic single-walled carbon nanotube thin film is first transferred as a buried gate electrode on the polished surface of the D-type fiber using an imprinting method, and the gate electrode region is defined by maskless photolithography and oxygen plasma etching. A 40 nm thick Al2O3 dielectric layer is grown on the D-type fiber substrate using atomic layer deposition (ALD), and windows are opened on the Al2O3 dielectric layer by reactive ion etching (RIE). Subsequently, Ti / Au source and drain electrodes are fabricated on the Al2O3 dielectric layer using a maskless photolithography-electron beam evaporation (EBV)-lift process, wherein the Ti layer thickness is 5 nm and the Au layer thickness is 50 nm. A semiconductor single-walled carbon nanotube thin film is deposited in the channel region between the two electrodes, and the channel range is defined by maskless photolithography and oxygen plasma etching. Finally, the phototransistor unit is fabricated by 1000... A CsPbBr3 quantum dot solution was spin-coated at rpm for 30s to form a uniform quantum dot thin layer, enabling the device to obtain a photosensitive layer composed of a quantum dot-carbon nanotube composite system. To avoid the quantum dots from being degraded by exposure to polar solvents such as remover PG and isopropanol in the preceding processing, the present invention places the quantum dot functionalization step in the final stage of the entire device processing flow.

[0073] (c) The method for manufacturing the light-controlled logic unit is as follows: Following the inverter manufacturing method in (a), an inverter is manufactured.

[0074] The gate and source of the load transistor are shorted to form a constant current source load, and the channel surface of the driving transistor is modified with CsPbBr3 quantum dots.

[0075] (d) The fabrication method of the wireless communication and energy unit is as follows: Ti / Au electrodes are prepared as conductive layers using a maskless photolithography-electron beam evaporation (EBV)-lift process, wherein the thickness of the Ti layer is 5 nm and the thickness of the Au layer is 50 nm. A 40 nm thick Al2O3 dielectric layer is deposited by atomic layer deposition (ALD), and windows are opened on the dielectric layer by reactive ion etching (RIE). The above conductive layer / dielectric layer deposition process is repeated alternately to finally form a layered spiral coil structure consisting of four conductive layers and three dielectric layers, so as to achieve compact size and efficient electromagnetic coupling.

[0076] Example Structure: A 4-layer metal coil (coil outer dimensions 210 μm × 70 μm, linewidth 4 μm, 3 turns per layer, DC resistance 1.3 kΩ, self-resonance approximately 560 MHz) is used for near-field wireless power transfer and RF signal transmission. Example Performance: In wireless power transfer testing, a measurable DC output can be detected at the receiver within a range of 1-60 cm; in RF signal transmission testing, a narrowband transmission peak can be observed at the receiver under 125 kHz excitation.

[0077] (e) Temperature sensing unit: A Ti / Au electrode was fabricated using a maskless photolithography-electron beam evaporation (EBV)-exfoliation process and positioned on the polished surface of a D-type optical fiber. This electrode can couple with the evanescent field of the fiber core, thereby exciting surface plasmon resonance. Subsequently, a polymethyl methacrylate (PMMA) film (molecular weight 950 kDa, solution concentration approximately 4 wt%) was spin-coated onto the Ti / Au electrode structure at a speed of 2000 rpm for 30 s to form a uniform coating layer.

[0078] Example 3:

[0079] A method for fabricating a multifunctional fiber optic electronic system based on D-type optical fiber includes the following specific steps:

[0080] Step 1: Preprocess the D-type optical fiber to obtain the preprocessed D-type optical fiber;

[0081] Specifically, the D-type optical fiber is immersed in electronic-grade acetone (purity ≥99.5%) for more than 20 minutes to remove the polymer resin coating layer on its surface; then, the D-type optical fiber is thoroughly rinsed with electronic-grade isopropanol (IPA, purity ≥99.5%) and completely dried under an electronic-grade nitrogen gas flow (purity ≥99.99%); after the polymer resin coating layer is removed, the D-type optical fiber is transferred and fixed to the surface of a silicon (100) wafer pre-coated with positive photoresist S1813; the positive photoresist is spin-coated at a speed of 500 rpm for 5 seconds to form a uniform thin film, and then cured at 180°C for 2.5 h to achieve complete curing and cross-linking of the positive photoresist, thereby forming a reliable mechanical adhesion layer, ensuring that the side polished surface of the D-type optical fiber is always horizontally exposed in subsequent processing to meet the requirements of subsequent processes;

[0082] Step 2: Fabricate various heterogeneous micro / nano devices on D-type optical fibers to obtain a complete multifunctional fiber optic electronic system based on D-type optical fibers;

[0083] (a) The fabrication methods for thin-film transistors, inverters, and ring oscillators in carbon-based logic circuit units are as follows:

[0084] First, a gate electrode was fabricated on the side-polished surface of a D-type optical fiber using maskless photolithography, electron beam evaporation (EBV), and lift-off processes. The gate electrode is a Ti / Au bilayer metal structure, with a Ti layer thickness of 5 nm and an Au layer thickness of 30 nm. Subsequently, an atomic layer deposition (ALD) process was used to deposit a 40 nm thick Al2O3 dielectric layer at 100-200 °C using trimethylaluminum and water as precursors. Reactive ion etching (RIE) was then performed under the following conditions: CF4 flow rate 50 sccm, cavity pressure 5.0 Pa, RF power 100 W, etching time 10 minutes. In the process of forming electrode contact holes by opening windows in the Al2O3 dielectric layer, Ti / Au source and drain electrodes are prepared on the surface of the Al2O3 dielectric layer using the same maskless photolithography-electron beam evaporation (EBV)-lift process as the gate electrode. To achieve uniform deposition of carbon nanotube network, the surface of D-type optical fiber is first functionalized with hexamethyldisilazane (HMDS). Then, the D-type optical fiber is immersed in carbon nanotube solution and kept at 50°C for 4 h to allow carbon nanotubes to be uniformly attached to the surface of D-type optical fiber by wet self-assembly. The carbon nanotube-modified D-type optical fiber is rinsed with toluene and isopropanol sequentially for 3-10 min each. Finally, the transistor channel range is defined by maskless photolithography and oxygen plasma etching (process conditions: O2 flow rate 180-200 sccm, RF power 180-200 W, etching time 30s-2 min), and finally thin film transistor is obtained.

[0085] Inverters and ring oscillators were fabricated using different layouts and the same fabrication methods as thin-film transistors.

[0086] (b) The fabrication method of the phototransistor unit is as follows: a buried gate field-effect transistor structure is selected. Specifically, a transparent metallic single-walled carbon nanotube thin film is first transferred as a buried gate electrode on the polished surface of the D-type fiber using an imprinting method, and the gate electrode region is defined by maskless photolithography and oxygen plasma etching. A 30 nm thick Al2O3 dielectric layer is grown on the D-type fiber substrate using atomic layer deposition (ALD), and windows are opened on the Al2O3 dielectric layer by reactive ion etching (RIE). Subsequently, Ti / Au source and drain electrodes are fabricated on the Al2O3 dielectric layer using a maskless photolithography-electron beam evaporation (EBV)-lift process, wherein the Ti layer thickness is 5 nm and the Au layer thickness is 30 nm. A semiconductor single-walled carbon nanotube thin film is deposited in the channel region between the two electrodes, and the channel range is defined by maskless photolithography and oxygen plasma etching. Finally, the 800-meter high-speed phototransistor unit is fabricated. A CsPbBr3 quantum dot solution is spin-coated at a rotation speed of rpm for 30 seconds to form a uniform quantum dot thin layer, enabling the device to obtain a photosensitive layer composed of a quantum dot-carbon nanotube composite system. To avoid the quantum dots from being degraded by exposure to polar solvents such as remover PG and isopropanol during the preceding processing, this invention places the quantum dot functionalization step in the final stage of the entire device processing flow.

[0087] (c) The method for manufacturing the light-controlled logic unit is as follows: Following the inverter manufacturing method in (a), an inverter is manufactured.

[0088] The gate and source of the load transistor are shorted to form a constant current source load, and the channel surface of the driving transistor is modified with CsPbBr3 quantum dots.

[0089] (d) The fabrication method of the wireless communication and energy unit is as follows: Ti / Au electrodes are prepared as conductive layers using a maskless photolithography-electron beam evaporation (EBV)-lift process, wherein the thickness of the Ti layer is 5 nm and the thickness of the Au layer is 30 nm. A 30 nm thick Al2O3 dielectric layer is deposited by atomic layer deposition (ALD), and windows are opened on the dielectric layer by reactive ion etching (RIE). The above conductive layer / dielectric layer deposition process is repeated alternately to finally form a layered spiral coil structure consisting of four conductive layers and three dielectric layers, so as to achieve compact size and efficient electromagnetic coupling.

[0090] (e) Temperature sensing unit: A Ti / Au electrode was fabricated using a maskless photolithography-electron beam evaporation (EBV)-exfoliation process and positioned on the polished surface of a D-type optical fiber. This electrode can couple with the evanescent field of the fiber core, thereby exciting surface plasmon resonance. Subsequently, a polymethyl methacrylate (PMMA) film (molecular weight 950 kDa, solution concentration approximately 4 wt%) was spin-coated onto the Ti / Au electrode structure at a speed of 1500 rpm for 30 s to form a uniform coating layer.

[0091] Example 4:

[0092] A method for fabricating a multifunctional fiber optic electronic system based on D-type optical fiber includes the following specific steps:

[0093] Step 1: Preprocess the D-type optical fiber to obtain the preprocessed D-type optical fiber;

[0094] Specifically, the D-type optical fiber is immersed in electronic-grade acetone (purity ≥99.5%) for more than 20 minutes to remove the polymer resin coating layer on its surface; then, the D-type optical fiber is thoroughly rinsed with electronic-grade isopropanol (IPA, purity ≥99.5%) and completely dried under an electronic-grade nitrogen gas flow (purity ≥99.99%); after the polymer resin coating layer is removed, the D-type optical fiber is transferred and fixed to the surface of a silicon (100) wafer pre-coated with positive photoresist S1813; the positive photoresist is spin-coated at 800 rpm for 5 seconds to form a uniform thin film, and then cured at 200°C for 2 hours to achieve complete curing and cross-linking of the positive photoresist, thereby forming a reliable mechanical adhesion layer, ensuring that the side polished surface of the D-type optical fiber is always horizontally exposed in subsequent processing to meet the requirements of subsequent processes;

[0095] Step 2: Fabricate various heterogeneous micro / nano devices on D-type optical fibers to obtain a complete multifunctional fiber optic electronic system based on D-type optical fibers;

[0096] (a) The fabrication methods for thin-film transistors, inverters, and ring oscillators in carbon-based logic circuit units are as follows:

[0097] First, a gate electrode was fabricated on the side-polished surface of a D-type optical fiber using maskless photolithography, electron beam evaporation (EBV), and lift-off processes. The gate electrode is a Ti / Au bilayer metal structure, with a Ti layer thickness of 3 nm and an Au layer thickness of 50 nm. Subsequently, an Al2O3 dielectric layer with a thickness of 50 nm was deposited at 100-200 °C using trimethylaluminum and water as precursors. Reactive ion etching (RIE) was then performed under the following conditions: CF4 flow rate 50 sccm, cavity pressure 5.0 Pa, RF power 100 W, etching time 10... In the process of forming electrode contact holes by opening windows in the Al2O3 dielectric layer, Ti / Au source and drain electrodes are prepared on the surface of the Al2O3 dielectric layer using the same maskless photolithography-electron beam evaporation (EBV)-lift process as the gate electrode. To achieve uniform deposition of carbon nanotube network, the surface of D-type optical fiber is first functionalized with hexamethyldisilazane (HMDS). Then, the D-type optical fiber is immersed in carbon nanotube solution and kept at 40℃ for 6 h, so that carbon nanotubes are uniformly attached to the surface of D-type optical fiber by wet self-assembly. The carbon nanotube-modified D-type optical fiber is rinsed with toluene and isopropanol in sequence, each step for 3-10 min. Finally, the transistor channel range is defined by maskless photolithography and oxygen plasma etching (process conditions: O2 flow rate 180-200 sccm, RF power 180-200 W, etching time 30s-2 min), and finally thin film transistor is obtained.

[0098] Inverters and ring oscillators were fabricated using different layouts and the same fabrication methods as thin-film transistors.

[0099] (b) The fabrication method of the phototransistor unit is as follows: a buried gate field-effect transistor structure is selected. Specifically, a transparent metallic single-walled carbon nanotube thin film is first transferred as a buried gate electrode on the polished surface of the D-type fiber using an imprinting method, and the gate electrode region is defined by maskless photolithography and oxygen plasma etching. A 50 nm thick Al2O3 dielectric layer is grown on the D-type fiber substrate using atomic layer deposition (ALD), and windows are opened on the Al2O3 dielectric layer by reactive ion etching (RIE). Subsequently, Ti / Au source and drain electrodes are fabricated on the Al2O3 dielectric layer using a maskless photolithography-electron beam evaporation (EBV)-lift-off process, wherein the Ti layer thickness is 3 nm and the Au layer thickness is 50 nm. A semiconductor single-walled carbon nanotube thin film is deposited in the channel region between the two electrodes, and the channel range is defined by maskless photolithography and oxygen plasma etching. Finally, the phototransistor unit is fabricated by a 500 nm thick layer. A CsPbBr3 quantum dot solution is spin-coated at a rotation speed of rpm for 50 seconds to form a uniform quantum dot thin layer, enabling the device to obtain a photosensitive layer composed of a quantum dot-carbon nanotube composite system. To avoid the quantum dots from being degraded by exposure to polar solvents such as remover PG and isopropanol in the preceding processing steps, this invention places the quantum dot functionalization step in the final stage of the entire device processing flow.

[0100] (c) The method for manufacturing the light-controlled logic unit is as follows: Following the inverter manufacturing method in (a), an inverter is manufactured.

[0101] The gate and source of the load transistor are shorted to form a constant current source load, and the channel surface of the driving transistor is modified with CsPbBr3 quantum dots.

[0102] (d) The fabrication method of the wireless communication and energy unit is as follows: Ti / Au electrodes are prepared as conductive layers using a maskless photolithography-electron beam evaporation (EBV)-lift process, wherein the thickness of the Ti layer is 3 nm and the thickness of the Au layer is 50 nm. A 50 nm thick Al2O3 dielectric layer is deposited by atomic layer deposition (ALD), and windows are opened on the dielectric layer by reactive ion etching (RIE). The above conductive layer / dielectric layer deposition process is repeated alternately to finally form a layered spiral coil structure consisting of four conductive layers and three dielectric layers, so as to achieve compact size and efficient electromagnetic coupling.

[0103] (e) Temperature sensing unit: A Ti / Au electrode was fabricated using a maskless photolithography-electron beam evaporation (EBV)-exfoliation process and positioned on the polished surface of a D-type optical fiber. This electrode can couple with the evanescent field of the fiber core, thereby exciting surface plasmon resonance. Subsequently, a polymethyl methacrylate (PMMA) film (molecular weight 950 kDa, solution concentration approximately 4 wt%) was spin-coated onto the Ti / Au electrode structure at a speed of 1000 rpm for 60 s to form a uniform coating layer.

[0104] Example 5:

[0105] A method for fabricating a multifunctional fiber optic electronic system based on D-type optical fiber includes the following specific steps:

[0106] Step 1: Preprocess the D-type optical fiber to obtain the preprocessed D-type optical fiber;

[0107] Specifically, the D-type optical fiber is immersed in electronic-grade acetone (purity ≥99.5%) for more than 20 minutes to remove the polymer resin coating layer on its surface; then, the D-type optical fiber is thoroughly rinsed with electronic-grade isopropanol (IPA, purity ≥99.5%) and completely dried under an electronic-grade nitrogen gas flow (purity ≥99.99%); after the polymer resin coating layer is removed, the D-type optical fiber is transferred and fixed to the surface of a silicon (100) wafer pre-coated with positive photoresist S1813; the positive photoresist is spin-coated at 1000 rpm for 3 seconds to form a uniform thin film, and cured at 240°C for 1 hour to achieve complete curing and cross-linking of the positive photoresist, thereby forming a reliable mechanical adhesion layer, ensuring that the side polished surface of the D-type optical fiber is always horizontally exposed in subsequent processing to meet the requirements of subsequent processes;

[0108] Step 2: Fabricate various heterogeneous micro / nano devices on D-type optical fibers to obtain a complete multifunctional fiber optic electronic system based on D-type optical fibers;

[0109] (a) The fabrication methods for thin-film transistors, inverters, and ring oscillators in carbon-based logic circuit units are as follows:

[0110] First, a gate electrode was fabricated on the side-polished surface of a D-type optical fiber using maskless photolithography, electron beam evaporation (EBV), and lift-off processes. The gate electrode is a Ti / Au bilayer metal structure, with a Ti layer thickness of 3 nm and an Au layer thickness of 30 nm. Subsequently, an atomic layer deposition (ALD) process was used to deposit a 60 nm thick Al2O3 dielectric layer at 100-200 °C using trimethylaluminum and water as precursors. Reactive ion etching (RIE) was then performed under the following conditions: CF4 flow rate 50 sccm, cavity pressure 5.0 Pa, RF power 100 W, etching time 10 minutes. In the process of forming electrode contact holes by opening windows in the Al2O3 dielectric layer, Ti / Au source and drain electrodes are prepared on the surface of the Al2O3 dielectric layer using the same maskless photolithography-electron beam evaporation (EBV)-lift process as the gate electrode. To achieve uniform deposition of carbon nanotube network, the surface of D-type optical fiber is first functionalized with hexamethyldisilazane (HMDS). Then, the D-type optical fiber is immersed in carbon nanotube solution and kept at 25°C for 12 h to allow carbon nanotubes to be uniformly attached to the surface of D-type optical fiber by wet self-assembly. The carbon nanotube-modified D-type optical fiber is rinsed with toluene and isopropanol sequentially for 3-10 min each step. Finally, the transistor channel range is defined by maskless photolithography and oxygen plasma etching (process conditions: O2 flow rate 180-200 sccm, RF power 180-200 W, etching time 30s-2 min), and finally thin film transistor is obtained.

[0111] Inverters and ring oscillators were fabricated using different layouts and the same fabrication methods as thin-film transistors.

[0112] (b) The fabrication method of the phototransistor unit is as follows: a buried gate field-effect transistor structure is selected. Specifically, a transparent metallic single-walled carbon nanotube thin film is first transferred as a buried gate electrode on the polished surface of the D-type fiber using an imprinting method, and the gate electrode region is defined by maskless photolithography and oxygen plasma etching. A 60 nm thick Al2O3 dielectric layer is grown on the D-type fiber substrate using atomic layer deposition (ALD), and windows are opened on the Al2O3 dielectric layer by reactive ion etching (RIE). Subsequently, Ti / Au source and drain electrodes are fabricated on the Al2O3 dielectric layer using a maskless photolithography-electron beam evaporation (EBV)-lift process, wherein the Ti layer thickness is 3 nm and the Au layer thickness is 30 nm. A semiconductor single-walled carbon nanotube thin film is deposited in the channel region between the two electrodes, and the channel range is defined by maskless photolithography and oxygen plasma etching. Finally, the phototransistor unit is fabricated by a 300 nm thick layer. A CsPbBr3 quantum dot solution was spin-coated at a rotation speed of rpm for 60 seconds to form a uniform quantum dot thin layer, enabling the device to obtain a photosensitive layer composed of a quantum dot-carbon nanotube composite system. To avoid the quantum dots from being degraded by exposure to polar solvents such as remover PG and isopropanol during the preceding processing, this invention places the quantum dot functionalization step in the final stage of the entire device processing flow.

[0113] (c) The method for manufacturing the light-controlled logic unit is as follows: Following the inverter manufacturing method in (a), an inverter is manufactured.

[0114] The gate and source of the load transistor are shorted to form a constant current source load, and the channel surface of the driving transistor is modified with CsPbBr3 quantum dots.

[0115] (d) The fabrication method of the wireless communication and energy unit is as follows: Ti / Au electrodes are prepared as conductive layers using a maskless photolithography-electron beam evaporation (EBV)-lift process, wherein the thickness of the Ti layer is 3 nm and the thickness of the Au layer is 30 nm. A 60 nm thick Al2O3 dielectric layer is deposited by atomic layer deposition (ALD), and windows are opened on the dielectric layer by reactive ion etching (RIE). The above conductive layer / dielectric layer deposition process is repeated alternately to finally form a layered spiral coil structure consisting of four conductive layers and three dielectric layers, so as to achieve compact size and efficient electromagnetic coupling.

[0116] (e) Temperature sensing unit: A Ti / Au electrode was fabricated using a maskless photolithography-electron beam evaporation (EBV)-exfoliation process and positioned on the polished surface of a D-type optical fiber. This electrode can couple with the evanescent field of the fiber core, thereby exciting surface plasmon resonance. Subsequently, a polymethyl methacrylate (PMMA) film (molecular weight 950 kDa, solution concentration approximately 4 wt%) was spin-coated onto the Ti / Au electrode structure at a speed of 1500 rpm for 60 s to form a uniform coating layer.

[0117] like Figure 2 As shown, the performance of the carbon-based logic circuit unit integrated with D-type optical fiber is characterized. Figure 2 (a) shows a scanning electron microscope (SEM) image of a carbon nanotube film deposited on the surface of an optical fiber (scale bar: 20 μm), indicating that the film has good uniformity. Figure 2 (b) shows the transfer characteristic curve of the thin-film transistor, which exhibits p-type switching characteristics; Figure 2 (c) shows the input-output characteristics of the inverter. The results show that the inverter achieves near rail-to-rail voltage conversion when the supply voltage VDD = −8V. Figure 2 (d) shows the output waveform of the ring oscillator, indicating its stability and suitability for accurate timing and signal-driven applications. The constructed carbon-based logic unit exhibits stable and reliable performance, meeting the expected logic function and timing requirements.

[0118] like Figure 3 As shown, the performance of the fiber-integrated optotransistor unit is characterized. Figure 3 (a) Figure 3 (b) shows the transfer curves of the device in external light detection mode and waveguide evanescent field detection mode. The test conditions are: light source wavelength λ = 405 nm, transistor gate voltage VDS = −1 V. It can be observed that as the incident light intensity increases, the device transfer curve shifts in the positive direction as a whole, showing an obvious grating modulation effect. In both detection modes, the device exhibits high sensitivity, fast response and stable photoelectric performance, indicating that the constructed phototransistor can effectively realize the electrical conversion and control of optical signals.

[0119] like Figure 4 As shown, the performance of the optical fiber integrated optical control logic unit is characterized. Figure 4 (a) shows the input-output characteristic curves of the device under illumination and darkness. Illumination is defined as logic "1" and darkness is defined as logic "0". The optical control logic unit can realize in-situ electrical demodulation of optical signals along the polished surface of the optical fiber and map the input optical signal logic "1" and "0" to the output voltage logic "0" and "1". The output voltage of −5 V corresponds to logic "1" and 0 V corresponds to logic "0", which shows the typical NOT gate function. Figure 4 (b) shows the process of in-situ demodulation of fiber waveguide signals by the device; when a bright / dark light pulse sequence with a period of 4 s is input into the fiber, the power of the output optical signal remains basically consistent with the input. At the same time, the optical control logic unit can parse the input light pulse bit by bit and output the corresponding logic inverse code, which further verifies its function as an optical control logic NOT gate and its reliable ability to map optical-electrical signals along the path.

[0120] like Figure 5As shown, the performance of the fiber-optic integrated wireless communication and energy unit is characterized. Figure 5 (a) shows the test results of the device’s radio frequency signal transmission performance. The received signal spectrum at different distances was measured under 125 kHz single-frequency excitation. Under 125 kHz continuous excitation, a narrow band main peak consistent with the excitation frequency appeared in the spectrum of the receiving end. The signal-to-noise ratio was significantly higher than the background level, indicating that the micro coil has effective magnetic induction coupling capability at this operating frequency. Figure 5 (b) shows the test results of the device's wireless power transmission performance. The time-domain induced voltage was measured at different transmit and receive distances (1-60 cm) under a constant excitation of 10 V, indicating that the fiber optic node has stable power reception capability in the sub-meter range. The wireless communication and power unit both exhibited stable and reliable performance in radio frequency signal transmission and DC power reception, verifying their feasibility in realizing contactless information transmission and power supply in fiber optic electronic systems.

[0121] like Figure 6 As shown, the performance of the fiber-optic integrated temperature sensing unit is characterized. Figure 6 (a) shows the transmission spectra of the fiber optic electronic system at different temperatures, demonstrating the measurable displacement of the surface plasmon resonance absorption valley as the temperature changes. Figure 6 (b) shows the relationship between the absorption valley wavelength and temperature. It exhibits a good linear blue shift trend, with a temperature sensitivity of −0.749 nm / °C and a linear fitting coefficient of 0.991. This temperature sensing unit can achieve highly sensitive, linear temperature monitoring in the range of 20-90 °C, verifying its reliability and feasibility in in-situ temperature sensing applications.

[0122] The results demonstrate that the multifunctional fiber optic electronic system based on D-type fiber proposed in this embodiment achieves in-situ integration and stable operation of carbon nanotube logic circuits, phototransistors, light-controlled logic gates, temperature sensors, and wireless micro-coils on a single fiber. This research marks the first time that multiple types of optoelectronic and wireless functional devices have been constructed and independently verified on a single fiber substrate, laying the device and process foundation for future construction of system-level fiber optic electronics platforms.

Claims

1. A multifunctional fiber optic electronic system based on D-type optical fiber, characterized in that, The invention includes D-shaped optical fibers and various heterogeneous micro / nano devices in situ integrated on the side polished surface of the D-shaped optical fibers. The D-shaped optical fibers are used for optical signal transmission and also serve as an integration substrate. The flat, processable area formed by polishing the sides of the fibers is called the side polished surface, which is used to integrate various heterogeneous micro / nano devices. The various heterogeneous micro / nano devices are used to realize in-situ signal detection, logic processing, temperature self-monitoring, and wireless energy and signal interaction functions of the optical fibers.

2. The multifunctional fiber optic electronic system based on D-type optical fiber according to claim 1, characterized in that, The heterogeneous micro / nano device includes a carbon-based logic circuit unit, a phototransistor unit, a light-controlled logic unit, a wireless communication and energy unit, and a temperature sensing unit. The phototransistor unit is used to convert optical signals into electrical signals, which serve as inputs to the carbon-based logic circuit unit. The carbon-based logic circuit unit is used to generate a periodic oscillation signal and perform digital logic operations on the input electrical signal based on the generated periodic oscillation signal to obtain the logic operation result; the generated periodic oscillation signal and the logic operation result are input to the wireless communication and energy unit; The optical control logic unit is used to realize the inverse mapping from optical signal to voltage logic signal, and the output voltage logic signal is used as the input of wireless communication and energy unit; the voltage logic signal corresponds to the logic state change of optical signal, and realizes in-situ electrical reading of optical signal transmitted in optical fiber without interrupting optical fiber transmission. The temperature sensing unit is used to realize in-situ temperature monitoring along the optical fiber and obtain temperature monitoring results. The wireless communication and energy unit, as a receiver, supplies power to the carbon-based logic circuit unit, phototransistor unit, light-controlled logic unit, and temperature sensing unit by receiving near-field wireless energy generated externally. As a transmitter, it enables the wireless transmission of periodic oscillation signals, logic operation results, and voltage logic signals.

3. A multifunctional fiber optic electronic system based on D-type optical fiber according to claim 1, characterized in that, The phototransistor unit uses a composite film composed of a semiconductor-type single-walled carbon nanotube thin film and a CsPbBr3 quantum dot thin film as the channel material to form a buried gate phototransistor. The buried gate phototransistor can operate in two optical coupling modes: external light source detection mode and waveguide evanescent field detection mode. In the external light source detection mode, external incident light directly irradiates the channel region of the buried gate phototransistor to generate a photoelectric response, converting the optical signal into an electrical signal. In the waveguide evanescent field detection mode, the optical signal of the guided wave mode propagating along the optical fiber forms an evanescent field on the side polished surface and couples with the channel to generate a photoelectric response, converting the optical signal into an electrical signal.

4. A multifunctional fiber optic electronic system based on D-type optical fiber according to claim 1, characterized in that, The carbon-based logic circuit unit is a logic circuit composed of several thin-film transistors, inverters, and ring oscillators; the thin-film transistors are thin-film transistors with semiconductor single-walled carbon nanotubes as the channel material, serving as basic active devices to realize electrical switching characteristics; the inverters are used to realize logic inversion functions; the ring oscillators are used to generate periodic oscillation signals, serving as a local clock source or directly outputting to the wireless communication and power unit.

5. A multifunctional fiber optic electronic system based on D-type optical fiber according to claim 1, characterized in that, The optical control logic unit is an inverter consisting of a load transistor and a drive transistor. The gate and source of the load transistor are shorted to form a constant current source load. The channel surface of the drive transistor is modified with CsPbBr3 quantum dots to regulate the threshold voltage. This allows the optical signal coupled to the channel region to directly control the conduction state of the drive transistor, thereby causing a change in the output voltage of the inverter. Specifically, the logic decision level is set according to the threshold voltage, which can realize a low output level when there is light input and a high output level when there is no light input, thus realizing the inverse mapping from optical signal to voltage logic signal.

6. A multifunctional fiber optic electronic system based on D-type optical fiber according to claim 1, characterized in that, The temperature sensing unit is based on a Ti / Au nanoelectrode with a PMMA thin film covering its surface to form a metal-dielectric interface structure. The Ti / Au nanoelectrode is coupled with the evanescent field of the optical fiber core to excite surface plasmon resonance. The PMMA thin film enhances the response of the interface refractive index to the surface plasmon resonance and provides mechanical encapsulation and protection. The unit achieves in-situ temperature monitoring along the optical fiber by monitoring the drift of the transmission spectrum absorption peak with changes in ambient temperature.

7. A multifunctional fiber optic electronic system based on D-type optical fiber according to claim 1, characterized in that, The wireless communication and energy unit is a multilayer spiral microcoil constructed by alternately depositing Ti / Au metal layers and Al2O3 dielectric layers on the polished surface of the optical fiber side.

8. A method for fabricating a multifunctional fiber optic electronic system based on D-type optical fiber, characterized in that, The specific steps include the following: Step 1: Preprocess the D-type optical fiber to obtain the preprocessed D-type optical fiber; Specifically, the D-type optical fiber is immersed in electronic-grade acetone for more than 20 minutes to remove the polymer resin coating layer on its surface; then, the D-type optical fiber is thoroughly rinsed with electronic-grade isopropanol and completely dried under an electronic-grade nitrogen gas flow; the D-type optical fiber is transferred and fixed to the surface of a silicon wafer pre-coated with positive photoresist S1813; the positive photoresist is spin-coated at a speed of 300-1000 rpm for 3-10 seconds to form a thin film, and then cured on a hot plate at 150-240℃ for 1-3 hours; Step 2: Fabricate various heterogeneous micro / nano devices on D-type optical fibers to obtain a complete multifunctional fiber optic electronic system based on D-type optical fibers; (a) The fabrication methods for thin-film transistors, inverters, and ring oscillators in carbon-based logic circuit units are as follows: First, a gate electrode is fabricated on the side-polished surface of a D-shaped optical fiber using maskless photolithography, electron beam evaporation, and lift-off processes. The gate electrode is a Ti / Au bilayer metal structure, with a Ti layer thickness of 3-10 nm and an Au layer thickness of 30-100 nm. Subsequently, an Al₂O₃ dielectric layer of 30-100 nm thickness is deposited at 100-200 °C using trimethylaluminum and water as precursors. Electrode contact holes are formed on the Al₂O₃ dielectric layer by reactive ion etching. Then, Ti / Au source and drain electrodes are fabricated on the Al₂O₃ dielectric layer using the same maskless photolithography-electron beam evaporation-lift-off process as the gate electrode. The surface of the D-shaped optical fiber is then functionalized with hexamethyldisilazane as a single layer. Finally, the D-shaped optical fiber is immersed in a carbon nanotube solution and held at 25-60 °C for 2-12 hours. h, carbon nanotubes are uniformly attached to the surface of D-type optical fiber by wet self-assembly; the carbon nanotube-modified D-type optical fiber is rinsed with toluene and isopropanol in sequence, each step for 3-10 min; finally, the transistor channel range is defined by maskless photolithography and oxygen plasma etching, and finally thin film transistor is obtained; inverters and ring oscillators are fabricated using different layouts according to the same fabrication method as thin film transistors. (b) The fabrication method of the phototransistor unit is as follows: A transparent metallic single-walled carbon nanotube film is first transferred as a buried gate electrode on the polished surface of the D-type optical fiber using an imprinting method, and the gate electrode region is defined by maskless photolithography and oxygen plasma etching. A 30-100 nm thick Al2O3 dielectric layer is grown on the D-type optical fiber substrate using atomic layer deposition, and windows are created on the Al2O3 dielectric layer by reactive ion etching. Subsequently, Ti / Au source and drain electrodes are fabricated on the Al2O3 dielectric layer using a maskless photolithography-electron beam evaporation-lifting process, wherein the Ti layer thickness is 3-10 nm and the Au layer thickness is 30-100 nm. A semiconductor single-walled carbon nanotube film is deposited in the channel region between the two electrodes, and the channel range is defined by maskless photolithography and oxygen plasma etching. Finally, a CsPbBr3 quantum dot solution of 10-60 μL is spin-coated at a rotation speed of 300-1000 rpm. s, forming a uniform quantum dot thin layer, to obtain a photosensitive layer composed of a quantum dot-carbon nanotube composite system; (c) The method for manufacturing the light-controlled logic unit is as follows: Following the inverter manufacturing method in (a), an inverter is manufactured. The gate and source of the load transistor are shorted to form a constant current source load, and the channel surface of the driving transistor is modified with CsPbBr3 quantum dots. (d) The fabrication method of wireless communication and energy unit is as follows: Ti / Au electrode is prepared as conductive layer by maskless photolithography-electron beam evaporation-lifting process, wherein the thickness of Ti layer is 3-10 nm and the thickness of Au layer is 30-100 nm. A 30-100 nm thick Al2O3 dielectric layer is deposited by atomic layer deposition, and windows are opened on the dielectric layer by reactive ion etching. The above conductive layer / dielectric layer deposition process is repeated alternately to finally form a layered spiral coil structure consisting of four conductive layers and three dielectric layers. (e) The temperature sensing unit is fabricated as follows: a Ti / Au electrode is prepared by a maskless photolithography-electron beam evaporation-exfoliation process and placed on the polished surface of the D-type optical fiber. Then, a polymethyl methacrylate (PMMA) film is spin-coated on the Ti / Au electrode structure at a speed of 1000-2000 rpm for 30-60s to form a uniform coating layer.

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