Optical nonlinear activator chip based on graphene photoelectric device and preparation method
By employing graphene optoelectronic devices in optical nonlinear activators, the issues of material compatibility and integration were resolved, resulting in high-performance optical nonlinear activators and improving the integration and bandwidth of optoelectronic devices.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-23
- Publication Date
- 2026-03-31
AI Technical Summary
Existing optical nonlinear activator solutions suffer from material system compatibility issues. Silicon-based optoelectronic integration platforms are slow, have low bandwidth and low photoresponsivity, and face problems of lattice mismatch and high cost when integrated with other materials.
By using graphene optoelectronic devices, passive optical devices such as waveguides and gratings are fabricated on a substrate, and then large-area graphene grown by CVD is transferred to design the optical path of the detector and modulator, realizing the optical-electrical-optical conversion, avoiding heterogeneous bonding process and reducing costs.
A highly integrated, high-bandwidth optical nonlinear activator was achieved, solving material compatibility issues, reducing costs, and improving the performance and integration of optoelectronic devices.
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Figure CN121763630A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of optoelectronic devices and optical signal processing technology, specifically relating to an optical nonlinear activator chip based on graphene optoelectronic devices and its fabrication method. Background Technology
[0002] Optical neural networks (ONNs) offer advantages in high parallelism and low power consumption, promising a solution to the rapidly growing demand for computing power. ONNs require the introduction of nonlinear relationships to describe different types of nonlinear systems and possess complex functional processing and learning capabilities; these nonlinear functional modules are called optical nonlinear activators. In the implementation of optical nonlinear activators, the photoelectric-electric-photoelectric conversion scheme is an important approach. Specifically, a portion of the incident light is converted into an electrical signal, which is then used to modulate the intensity of another portion of the incident light, thus achieving a nonlinear transformation from incident to outgoing light. Currently, mainstream ONNs are primarily implemented using silicon-based optoelectronic integration platforms. Silicon materials are slow, have small bandwidth, and low photoresponsivity. Silicon detectors require epitaxial germanium to improve photoresponsivity, facing lattice mismatch issues. Silicon's nonlinear effects are weak, resulting in low modulation efficiency; silicon modulators require larger device sizes to meet performance requirements. Integration with materials with better modulation and detection performance, such as lithium niobate and germanium, presents greater challenges in integration process compatibility and cost. A highly integrated, high-bandwidth solution for optical nonlinear activators is still lacking.
[0003] Graphene, as a novel two-dimensional material, possesses excellent properties such as ultra-high carrier mobility and an ultra-wide bandwidth of photoelectric interaction, demonstrating its application potential in photodetectors, electro-optic modulators, and other fields. Graphene maintains the same absorptivity across the visible to mid-infrared range; its theoretical mobility can reach 2 × 10⁻⁶. 5 cm 2 Theoretically, graphene's modulation efficiency as an electro-optic modulator can reach more than 10 times that of thin-film lithium niobate, while possessing low insertion loss performance comparable to lithium niobate. More importantly, graphene's two-dimensional nature allows it to be combined with other materials via van der Waals interactions, making it compatible with virtually any substrate without considering lattice matching issues. These excellent properties make graphene a promising key functional material in optoelectronic devices and systems, with the potential to solve core problems such as integration density, speed, and power consumption in optical nonlinear activators, thus contributing to the development of optical neural networks and optical computing. Summary of the Invention
[0004] This invention addresses the problems existing in the prior art by providing an optical nonlinear activator chip based on graphene optoelectronic devices and its fabrication method. It can leverage the optoelectronic properties and integration advantages of graphene, enabling the on-chip integrated design and fabrication of graphene detectors and modulators, realizing optical nonlinear functional modules, and promoting the development of on-chip integration of nonlinear optical neural networks.
[0005] To address the above technical problems, this invention provides the following technical solution: an optical nonlinear activator chip based on graphene optoelectronic devices, comprising a detector optical path and a modulator optical path. The detector optical path includes: a first light incident module, a detector waveguide, and a graphene photovoltage detector; The first light incident module is located above the substrate and is used to receive the input light signal; the detector waveguide is located on the upper surface of the substrate and is connected to the first light incident module; the graphene photovoltage detector is located above the detector waveguide. The modulator optical path includes: a second optical incident module, a modulator waveguide, an optical exit module, and a graphene electro-optic modulator; A second light incident module, located above the substrate, receives continuous light signals at its input. A modulator waveguide, located on the upper surface of the substrate, has one end connected to the second light incident module. A graphene electro-optic modulator is located above the modulator waveguide. A light exit module, located above the substrate, is connected to the other end of the modulator waveguide. The upper and lower graphene layers of the graphene electro-optic modulator both cover the modulator waveguide and are symmetrically arranged about the waveguide. The two electrodes of the graphene electro-optic modulator are also symmetrically arranged. In the optical path of the detector, one end electrode of the graphene photovoltage detector is connected to the contact electrode of the active region of the lower layer of the modulator; the detector converts the input optical signal into a voltage signal, and then inputs the voltage signal into the modulator to modulate continuous light, and outputs the nonlinearly converted optical signal.
[0006] Furthermore, the aforementioned first and second optical incident modules and optical exit modules are vertically coupled gratings or end-face coupled waveguides.
[0007] Furthermore, the distances between the electrodes on both sides of the detector and the detector waveguide are different.
[0008] This invention also provides a method for fabricating an optical nonlinear activator chip based on graphene optoelectronic devices, the method comprising the following steps: Step 1: Fabricate the light incident module, light emitting module, detector waveguide, and modulator waveguide on the substrate, and perform surface planarization process; Step 2: Transfer the lower graphene layer and prepare the detector optical path channel region and the lower active region of the modulator optical path by photolithography isolation. Then, prepare the detector electrode and the contact electrode of the lower graphene layer of the modulator by photolithographic evaporation. The electrodes on both sides of the detector have different spacing from the waveguide of the graphene electro-optic detector, which is used to convert the input signal light into voltage. The contact electrode of the lower graphene layer of the modulator is connected to one side electrode of the detector. Step 3: Prepare the dielectric; Step 4: Transfer the upper graphene layer and prepare the upper graphene film layer of the modulator by photolithography isolation. Then, prepare the contact electrode of the upper graphene layer of the modulator by photolithographic evaporation. Then, expose the electrode in step 2 by photolithographic etching process. The upper and lower graphene layers of the modulator are both covered with waveguides and are symmetrically arranged about the waveguides. The two electrodes of the modulator are symmetrically arranged.
[0009] Furthermore, the aforementioned substrate uses an SOI wafer, and waveguide passive devices are fabricated on the silicon layer on the SOI using an etching process, or at least one of gallium arsenide, indium phosphide, silicon carbide, and lithium niobate is used as the substrate and waveguide processing is performed.
[0010] Furthermore, the aforementioned input and output of optical signals employ vertically coupled gratings or direct end-face coupling methods.
[0011] Furthermore, in steps 2 and 4 above, the graphene layer is selected from CVD-grown graphene films or graphene films obtained by mechanical exfoliation of graphite sheets, and the number of graphene layers is one of single layer, double layer or multiple layer.
[0012] Compared with the prior art, the beneficial technical effects of the present invention using the above technical solution are as follows: (1) The optical nonlinear activator chip based on graphene optoelectronic devices proposed in this invention avoids the compatibility problems between different material systems in traditional optical nonlinear activator schemes, including problems such as lattice matching and process compatibility. It can first prepare passive optical devices such as waveguides and gratings on the substrate, and then transfer large-area graphene grown by CVD, which has the potential for large-scale preparation.
[0013] (2) This invention utilizes graphene detectors and modulators to perform photo-electric-optical conversion to achieve optical nonlinear relationships, giving full play to the advantages of graphene in optoelectronic devices and optoelectronic integration. It does not require complex and expensive bonding, alignment and other processes, and has a low cost. It can provide a technical solution for monolithic, highly integrated optical nonlinear activators. Attached Figure Description
[0014] Figure 1 This is a top view of the optical nonlinear activator chip based on graphene optoelectronic devices according to the present invention.
[0015] Figure 2 This is a side view of the optical nonlinear activator chip based on graphene optoelectronic devices according to the present invention.
[0016] Figure 3 This is a flowchart of the optical nonlinear activator chip fabrication method based on graphene optoelectronic devices according to the present invention. In the figure, (a) is a flowchart of fabricating a vertically coupled grating and waveguide on a substrate; (b) is a flowchart of transferring the first layer of graphene on the waveguide; (c) is a flowchart of isolating the first layer of graphene to fabricate the detector channel region and the lower graphene film layer of the modulator; (d) is a flowchart of fabricating electrodes; (e) is a flowchart of fabricating a dielectric layer; (f) is a flowchart of transferring the second layer of graphene on the dielectric layer; (g) is a flowchart of isolating the second layer of graphene to fabricate the upper graphene film layer of the modulator; (h) is a flowchart of fabricating electrodes; and (i) is a flowchart of etching the medium.
[0017] In the figure, 1a - vertical coupling grating of the first light incident module, 1b - vertical coupling grating of the second light incident module, 1c - vertical coupling grating of the light exiting module, 2a - detector waveguide, 2b - modulator waveguide, 3a - graphene film layer of the detector, 3b - lower graphene film layer of the modulator, 4a - detector electrode, 4b - contact electrode of the lower active region of the modulator, 5 - dielectric, 6a - upper graphene film layer of the modulator, 7 - contact electrode of the upper graphene layer of the modulator. Detailed Implementation
[0018] To better understand the technical content of the present invention, specific embodiments are described below in conjunction with the accompanying drawings.
[0019] In this invention, various aspects of the invention are described with reference to the accompanying drawings, in which numerous illustrative embodiments are shown. Embodiments of the invention are not limited to those depicted in the drawings. It should be understood that the invention is implemented through any of the various concepts and embodiments described above, as well as the concepts and embodiments described in detail below, because the concepts and embodiments disclosed herein are not limited to any particular implementation. Furthermore, some aspects of the invention disclosed may be used alone or in any suitable combination with other aspects of the invention disclosed.
[0020] like Figure 3 As shown in Example 1, a method for fabricating an optical nonlinear activator chip based on graphene optoelectronic devices is provided, and the steps are as follows: Step 1: Electron beam photoresist mask patterns for the vertically coupled grating 1a of the first light incident module, the vertically coupled grating 1b of the second light incident module, and the vertically coupled grating 1c of the light exiting module are prepared on the substrate using electron beam exposure and development technology. Using electron beam photoresist as a mask, inductively coupled plasma etching is used to etch the vertically coupled grating 1a of the first light incident module, the vertically coupled grating 1b of the second light incident module, and the vertically coupled grating 1c of the light exiting module, followed by photoresist removal and cleaning.
[0021] Furthermore, the substrate uses an SOI wafer, and waveguide end-face coupling can be selected to achieve light input and output. The silicon thickness on the SOI substrate is 220 nm, the electron beam resist is AR-P 6200, the etching depth is 80 nm, and the etching gas is a mixture of chlorine and argon.
[0022] Step 2: Electron beam photoresist mask patterns for the waveguides are fabricated on the substrate using electron beam exposure and development technology. Using the electron beam photoresist as a mask, detector waveguide 2a and modulator waveguide 2b are etched using inductively coupled plasma etching, followed by photoresist removal and cleaning. Figure 3 As shown in (a). The electron beam resist was AR-P 6200, the etching depth was 220 nm, and the etching gas was a mixture of chlorine and argon.
[0023] Furthermore, the silicon layer on the SOI substrate is etched to fabricate a silicon waveguide. Alternatively, gallium arsenide, indium phosphide, silicon carbide, or lithium niobate can be used as the substrate for waveguide fabrication and subsequent processing. Step 3: Grow a silicon oxide capping layer of 0.5-2 μm and polish the wafer using a chemical mechanical polishing process to achieve surface planarization.
[0024] Furthermore, a 1 μm thick silicon oxide capping medium is grown. To ensure tight adhesion of the graphene in the next step, a BCB film is coated on the surface of the capping medium using a coating process and then cured. The thickness of the BCB film is 2-10 nm, preferably 5 nm.
[0025] Step 4: Transfer the graphene film onto the chip surface and bake it for an extended period of time, such as... Figure 3 As shown in (b).
[0026] Furthermore, a wet transfer process is used to transfer the large-area CVD-grown graphene film, followed by baking at 90°C for more than 8 hours, preferably 10 hours. Alternatively, the graphene film can be obtained by mechanical exfoliation and then transferred using either a dry or wet method.
[0027] Step 5: A photoresist mask for the graphene pattern is prepared using planar photolithography and development technology. Subsequently, oxygen plasma oxidation is used to complete the graphene patterning, followed by photoresist removal and cleaning. Figure 3As shown in (c). The graphene pattern for this step is: the graphene film layer 3a of the detector and the lower graphene film layer 3b of the modulator.
[0028] Furthermore, the length of the waveguide covered by the graphene film layer 3a of the detector and the lower graphene film layer 3b of the modulator is 20-1000 μm. The lower graphene film layer 3b of the modulator extends 1-2 μm further to the right of the modulator waveguide 2b. Preferably, the length of the waveguide covered by the graphene film layer 3a of the detector is 100 μm; the length of the waveguide covered by the lower graphene film layer 3b of the modulator is 200 μm, and it extends 1 μm further to the right of the modulator waveguide 2b.
[0029] Step 6: The electrode pattern is prepared using planar photolithography and development technology. The detector electrode 4a and the contact electrode 4b of the lower active region of the modulator are prepared using electron beam evaporation and lift-off processes, as follows. Figure 3 As shown in (d).
[0030] Furthermore, the electrodes can be made of one or more of titanium, gold, chromium, nickel, platinum, silver, copper, and palladium, with a thickness of 20-200 nm. The electrodes on both sides of the detector are spaced differently from the waveguide, and the conversion of light to voltage is achieved through a non-equilibrium photothermoelectric effect. The distance between the detector electrode 4a and the detector waveguide 2a is 1-2 μm, and the distance between the contact electrode 4b of the detector electrode and the active region of the lower layer of the modulator and the detector waveguide 2a is 5-10 μm, and the distance between the contact electrode 4b and the modulator waveguide 2b is 2-4 μm.
[0031] Preferably, the electrode pattern is prepared using planar photolithography, by sequentially evaporating 20 nm titanium, 200 nm gold, and 10 nm titanium. The distance between the detector electrode 4a and the detector waveguide 2a is 1 μm, the distance between the contact electrode 4b of the lower active region of the modulator and the detector waveguide 2a is 6 μm, and the distance between the modulator waveguide 2b is 2 μm. The different distances between the waveguide 2a and the detector electrodes 4a on both sides and the contact electrode 4b of the lower active region of the modulator allow the light energy in the waveguide to be converted into voltage through the photothermoelectric effect.
[0032] Step 7: The graphene channels are exposed by corroding gold with a cyanide solution, and then a dielectric layer 5 is grown. (Example:...) Figure 3 As shown in (e).
[0033] Furthermore, the dielectric 5 can be one of silicon oxide, silicon nitride, hafnium oxide, aluminum oxide, aluminum nitride, and boron nitride, with a thickness of 30-100 nm, preferably a 20 nm thick hafnium oxide dielectric 5.
[0034] Furthermore, to ensure tight adhesion of graphene in the next step, a BCB film is coated on the surface of the medium using a coating process and then cured. The thickness of the BCB film is 2-10 nm, preferably 5 nm thick.
[0035] Step 8: Transfer the graphene film onto the chip surface and bake it for an extended period of time, such as... Figure 3 As shown in (f).
[0036] Furthermore, a wet transfer process is used to transfer the large-area CVD-grown graphene film, followed by baking at 90°C for more than 8 hours, preferably 10 hours. Alternatively, the graphene film can be obtained by mechanical exfoliation and then transferred using either a dry or wet method.
[0037] Step 9: A photoresist mask with a graphene pattern is prepared using planar photolithography and development technology. Subsequently, oxygen plasma oxidation is used to complete the graphene patterning, forming the upper graphene film layer 6a of the modulator. The photoresist is then removed and the area is cleaned. Figure 3 As shown in (g).
[0038] Furthermore, the upper graphene film layer 6a of the modulator and the lower graphene film layer 3b of the modulator cover the same waveguide region. The graphene layer 6a extends 1-2 μm, preferably 1 μm, on the left side of the waveguide. The appropriate extension ensures that both the upper and lower graphene layers effectively cover the waveguide and form a capacitor, but it cannot cover too much to avoid excessive capacitance and reduced bandwidth.
[0039] Step 10: Electrode patterns are fabricated using planar photolithography and development technology. Contact electrodes 7 of the upper graphene layer of the modulator are then fabricated using electron beam evaporation and lift-off processes. Figure 3 As shown in (h).
[0040] Furthermore, the contact electrode 7 of the upper graphene layer of the modulator can be made of one or more of titanium, gold, chromium, nickel, platinum, silver, copper, and palladium, with a thickness of 20-500 nm. Preferably, 20 nm of titanium and 200 nm of gold are evaporated, and the contact electrode 7 of the upper graphene layer of the modulator is prepared by peeling. The contact electrode 7 of the upper graphene layer of the modulator is 2 μm away from the contact electrode 4b of the lower active region of the modulator and the waveguide 2b of the modulator.
[0041] Step 11: A photoresist mask is used to fabricate the pattern of the detector electrode 4a and the contact electrode 4b of the lower active region of the modulator using planar photolithography. Using the photoresist as a mask, inductively coupled plasma etching is employed to remove the dielectric layer, exposing the electrodes. The photoresist is then stripped away to complete the fabrication of the detector chip. Figure 3 As shown in (i).
[0042] This embodiment uses the same process to fabricate both the graphene detector and modulator, realizing a graphene optoelectronic nonlinear activator chip. This avoids the heterogeneous bonding process required when the detector and modulator use different material systems, saving on consumables such as photoresist and metals, and significantly reducing wafer fabrication costs. This approach is highly practical for developing on-chip integrated high-performance optical nonlinear activators.
[0043] Example 2: An optical nonlinear activator chip based on graphene optoelectronic devices, prepared according to the method of Example 1, such as... Figure 1-2 As shown, the chip includes: a detector optical path and a modulator optical path. The detector optical path includes: a first light incident module, a detector waveguide 2a, and a graphene photovoltage detector. The first light incident module is located above the substrate and is used to receive the input light signal; the detector waveguide 2a is located on the upper surface of the substrate and is connected to the first light incident module; the graphene photovoltage detector is located above the detector waveguide 2a. The modulator optical path includes: a second optical incident module, a modulator waveguide 2b, an optical exit module, and a graphene electro-optic modulator; The second light incident module is located above the substrate, and its input end receives continuous light signals; the modulator waveguide 2b is located on the upper surface of the substrate, and one end of the modulator waveguide 2b is connected to the second light incident module; the graphene electro-optic modulator is located above the modulator waveguide 2b; and the light emitting module is located above the substrate and is connected to the other end of the modulator waveguide 2b. Vertically coupled gratings 1a, 1b, and 1c serve as the first light incident module, the first light incident module, and the light exit module, respectively.
[0044] Both the upper and lower graphene layers of the modulator cover the modulator waveguide 2b and are symmetrically arranged about the modulator waveguide 2b; the contact electrode 7 of the upper graphene layer of the modulator is symmetrically arranged with respect to the contact electrode 4b of the lower active region of the modulator, and the distance between the electrodes at both ends of the detector and the detector waveguide is different.
[0045] In the optical path of the detector, one end electrode 4a of the graphene photovoltage detector is connected to the contact electrode 4b of the active region of the lower layer of the modulator; the detector converts the input optical signal into a voltage signal, and then inputs the voltage signal into the modulator to modulate continuous light, and outputs the nonlinearly converted optical signal.
[0046] In the graphene optoelectronic device-based optical nonlinear activator chip of this invention, the nonlinearity mainly originates from the graphene electro-optic modulator. The modulator adopts a graphite grating structure, and the light absorption rate of graphene is modulated by its Fermi level position. When the Fermi level is located at the Dirac point, the light absorption rate is maximum. When the energy difference between the Fermi level and the Dirac point reaches more than half the photon energy, the light absorption rate is almost zero. Therefore, the relationship between the output light intensity and the modulator input voltage is nonlinear. When the graphene optoelectronic device-based optical nonlinear activator chip is working, a beam of light signal modulated with the information to be processed is input to the waveguide of the detector optical path through a vertically coupled grating. It is linearly converted into a photovoltage signal by the graphene photovoltage detector, and this photovoltage signal is input to the graphene electro-optic modulator as the modulation voltage. A beam of unmodulated continuous light is input to the waveguide of the modulator optical path through a vertically coupled grating. The light intensity is modulated by the graphene electro-optic modulator, and the light intensity has a nonlinear relationship with the modulation voltage. It is output by the vertically coupled grating. Due to the nonlinear modulation of the graphene electro-optic modulator, the output optical signal exhibits a nonlinear conversion effect relative to the input optical signal, thus realizing a nonlinear activation function. "The aforementioned optical nonlinear activator chip based on graphene optoelectronic devices is generally used as a nonlinear module in an optical neural network chip for nonlinear optical transformation operations. Together with linear optical modules such as interference and radiation modules, it forms the neurons in the optical neural network. The addition of the optical nonlinear activator enables the optical neural network to achieve complex functional processing and learning behaviors, expanding the processing capabilities and application range of the optical neural network."
[0047] While the present invention has been described above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.
Claims
1. An optical nonlinear activator chip based on graphene optoelectronic devices, characterized in that, Including the detector optical path and the modulator optical path, The detector optical path includes: a first light incident module, a detector waveguide, and a graphene photovoltage detector; The first light incident module is located above the substrate and is used to receive the input light signal; the detector waveguide is located on the upper surface of the substrate and is connected to the first light incident module; the graphene photovoltage detector is located above the detector waveguide. The modulator optical path includes: a second optical incident module, a modulator waveguide, an optical exit module, and a graphene electro-optic modulator; A second light incident module, located above the substrate, receives continuous light signals at its input. A modulator waveguide, located on the upper surface of the substrate, has one end connected to the second light incident module. A graphene electro-optic modulator is located above the modulator waveguide. A light exit module, located above the substrate, is connected to the other end of the modulator waveguide. The upper and lower graphene layers of the graphene electro-optic modulator both cover the modulator waveguide and are symmetrically arranged about the waveguide. The two electrodes of the graphene electro-optic modulator are also symmetrically arranged. In the optical path of the detector, one end electrode of the graphene photovoltage detector is connected to the contact electrode of the active region of the lower layer of the modulator; the detector converts the input optical signal into a voltage signal, and then inputs the voltage signal into the modulator to modulate continuous light, and outputs the nonlinearly converted optical signal.
2. The optical nonlinear activator chip based on graphene optoelectronic devices according to claim 1, characterized in that, The first and second light incident modules and the light exit module are vertically coupled gratings or end-face coupled waveguides.
3. The optical nonlinear activator chip based on graphene optoelectronic devices according to claim 1, characterized in that, The distances between the electrodes on both sides of the detector and the detector waveguide are different.
4. A method for fabricating an optical nonlinear activator chip based on graphene optoelectronic devices, used to obtain the optical nonlinear activator chip based on graphene optoelectronic devices as described in any one of claims 1-3, characterized in that, Includes the following steps: Step 1: Fabricate the light incident module, light emitting module, detector waveguide, and modulator waveguide on the substrate, and perform surface planarization process; Step 2: Transfer the lower graphene layer and prepare the detector optical path channel region and the lower active region of the modulator optical path by photolithography isolation. Then, prepare the detector electrode and the contact electrode of the lower graphene layer of the modulator by photolithographic evaporation. The electrodes on both sides of the detector have different spacing from the waveguide of the graphene electro-optic detector, which is used to convert the input signal light into voltage. The contact electrode of the lower graphene layer of the modulator is connected to one side electrode of the detector. Step 3: Prepare the dielectric; Step 4: Transfer the upper graphene layer and prepare the upper graphene film layer of the modulator by photolithography isolation. Then, prepare the contact electrode of the upper graphene layer of the modulator by photolithographic evaporation. Then, expose the electrode in step 2 by photolithographic etching process. The upper and lower graphene layers of the modulator are both covered with waveguides and are symmetrically arranged about the waveguides. The two electrodes of the modulator are symmetrically arranged.
5. The method for fabricating an optical nonlinear activator chip based on graphene optoelectronic devices according to claim 4, characterized in that, The substrate is an SOI wafer, and waveguide passive devices are fabricated by etching the silicon layer on the SOI. Alternatively, at least one of gallium arsenide, indium phosphide, silicon carbide, and lithium niobate can be used as the substrate and waveguides can be fabricated.
6. The method for fabricating an optical nonlinear activator chip based on graphene optoelectronic devices according to claim 4, characterized in that, The input and output of optical signals are achieved using vertically coupled gratings or direct end-face coupling.
7. The method for fabricating an optical nonlinear activator chip based on graphene optoelectronic devices according to claim 4, characterized in that, In steps 2 and 4, the graphene layer is selected from CVD-grown graphene films or graphene films obtained by mechanical exfoliation of graphite sheets, and the number of graphene layers is one of single layer, double layer or multiple layer.