Optical phased array controlled by optical switch

Abstract

The utility model discloses an optical switch control optical phased array which comprises a silicon substrate, a silicon dioxide buried oxide layer and a silicon nitride layer, the silicon dioxide buried oxide layer is arranged on the upper surface of the silicon substrate, the silicon nitride layer is arranged on the upper surface of the silicon dioxide buried oxide layer, and a phase change material heterogeneous layer is arranged on the upper surfaces of the silicon dioxide buried oxide layer and the silicon nitride layer. And the metal electrode layer is arranged on the upper surface of the phase change material heterogeneous layer. The on-chip integrated fast and low-power consumption optical switch is realized by using the phase change material GST. Reversible phase change of the GST material between an amorphous state and a crystalline state only needs nanosecond magnitude, the refractive index difference between the amorphous state and the crystalline state is remarkable, and rapid switching can be achieved by applying pulse voltage through an electrode. Compared with a traditional thermo-optic and electro-optic effect switch, the size is smaller, power consumption is lower, the speed is higher, the technology is compatible with a CMOS circuit, and integration is easy.

Description

Technical Field

[0001] The utility model relates to the field of optoelectronic devices, specifically to an optical switch for controlling an optical phased array. Background Art

[0002] An optical switch is an important part of an optical integrated circuit, used to achieve switching, routing, and optical cross-connection. It has a wide range of application scenarios in optical communication and networks, optical computing, lidar, and other sensing fields. Starting from silicon nitride photonic devices, this paper studies an integrated optical switch of the Mach-Zehnder Interferometer (MZI) type, and characterizes important parameters such as the switching speed, bandwidth, power consumption, extinction ratio, insertion loss, crosstalk, and footprint of the integrated device, and completes the design of relevant device parameters according to different scenario requirements. Micro / nano-scale optical switches are considered the core of the next-generation ultrafast communication and signal processing systems. At the current stage of optoelectronic hybridization, it is necessary to develop optical switch technology to break through the bottleneck of information exchange. As a core device, the optical switch plays a crucial role in constructing an on-chip ultrafast all-optical switching network.

[0003] Phase change materials can reversibly and rapidly switch between two different atomic arrangements or states (amorphous and crystalline), and both states have different optical and electrical properties. Among phase change materials, GST has attracted much attention due to its fast crystallization speed, good amorphous stability, large electrical and optical differences between the two states, and compatibility with existing CMOS manufacturing processes. GST has a 20% reflectivity difference between the amorphous phase and the FCC crystalline phase (amorphization time is less than 1 ns, crystallization time is less than 13 ns), and was initially used as an information recording medium for high-speed non-volatile optical data storage media (DVD-RAM). A laser scans along the information track to read information, and judges the binary signals "0" and "1" according to the "high" and "low" of the reflectivity. In addition to the huge change in reflectivity, there is a three-order-of-magnitude resistance difference (KΩ - MΩ) between its amorphous and crystalline states, so GST is also used in electronic phase change memories.

[0004] And the integration of chips is an important trend in the development of current mid-infrared supercontinuum light sources. In recent years, relevant research institutions at home and abroad have increased the development of the integrated application of optical phased arrays. Therefore, realizing an on-chip integrated optical switch control optical phased array system has considerable economic and social significance.

[0005] In addition, the integrated ultrafast optical switch enables different emission modes of the optical phased array to be integrated on the same chip, making the application of the optical phased array more extensive. At present, the optical phased array with a single scanning mode generated by a system cannot meet some actual application requirements, and the packaging integration of the optical phased array is also a major problem. Summary of the Invention

[0006] Based on this, in view of the above technical problems, it is necessary to provide an optical switch-controlled optical phased array to solve the problems of the ultrafast optical switch regulating the optical path and the single-emission-mode optical phased array in the prior art.

[0007] Based on the above object, the optical switch-controlled optical phased array includes: a silicon substrate, a silicon dioxide buried oxide layer, and a silicon nitride layer. The silicon dioxide buried oxide layer is disposed on the upper surface of the silicon substrate, the silicon nitride layer is disposed on the upper surface of the silicon dioxide buried oxide layer, a phase change material heterolayer is disposed on the upper surfaces of the silicon dioxide buried oxide layer and the silicon nitride layer, and a metal electrode layer is disposed on the upper surface of the phase change material heterolayer;

[0008] The silicon nitride layer includes: an optical switch module for regulating optical splitting, a heterogeneous integrated silicon nitride waveguide module for controlling the end-face emission OPA, and a heterogeneous integrated silicon nitride waveguide module for controlling the grating emission OPA. The system uses the optical switch module to perform controllable optical splitting adjustment on the input light, and the latter two modules can select the scanning mode and emission mode of the optical phased array;

[0009] The optical switch module includes a Mach-Zehnder interferometer, on both sides of the long arm of which a first electrode, a second electrode, and a third electrode are provided. The first electrode and the third electrode are connected to the positive pole of the power supply, and the second electrode is connected to the negative pole of the power supply. A voltage is applied to the phase change material heterolayer through the electrodes to cause the phase change material to change phase, change the phase difference of the interference arms, and achieve 0 / 1 signal splitting regulation of the rear-end optical path;

[0010] The heterogeneous integrated silicon nitride waveguide module for end-face emission OPA includes N parallel heterogeneous integrated silicon nitride waveguides, which are used as the emission array elements of the optical phased array to achieve light convergence and perform horizontal-direction scanning imaging on the target.

[0011] Preferably, the grating emission optical phased array module includes N parallel heterogeneous integrated silicon nitride waveguides, and a grating structure is provided at the emission end of each waveguide to diffract the incident light and make the light emit perpendicular to the chip plane, realizing a vertical-direction scanning mode different from the end-face emission.

[0012] Preferably, the thickness of the silicon substrate is greater than the thickness of the silicon dioxide buried oxide layer, the thickness of the silicon dioxide buried oxide layer is greater than the thickness of the silicon nitride layer, and the thickness of the silicon nitride layer is greater than the thickness of the phase change material heterolayer.

[0013] Preferably, the thickness of the silicon substrate is 500 μm, the thickness of the silicon dioxide buried oxide layer is 2 μm, the thickness of the silicon nitride layer is 0.5 μm, and the thickness of the phase change material heterolayer is 0.1 μm.

[0014] Preferably, the phase change material heterolayer uses GST phase change material, and the refractive index difference between the amorphous state and the crystalline state is "n". By applying a voltage U to the GST through an electrode, the GST is changed from the amorphous state to the crystalline state, and the refractive indices between the two states satisfy the following relationship:

[0015]

[0016] wherein, is the refractive index of the GST crystalline state, is the refractive index of the GST amorphous state, is the material constant, is the pulse duration.

[0017] Preferably, the voltage range applied between the first electrode and the second electrode and between the second electrode and the third electrode is 0 to 30V.

[0018] Preferably, the optical switch module, the end-face-emitting OPA heterogeneously integrated silicon nitride waveguide module, and the grating-emitting optical phased array module in the silicon nitride layer are interconnected through silicon nitride waveguides to achieve low-loss optical interconnection between different modules.

[0019] Compared with the prior art, the advantages of the present invention are as follows: The present invention uses three silicon nitride structure modules to process the input light, and can quickly, efficiently and low-power adjust different emission modes of the optical phased array for scanning, making the optical phased array easier to integrate and apply;

[0020] 1. The present invention uses the phase change material GST to achieve a fast and low-power optical switch integrated on a chip. The reversible phase change of the GST material between the amorphous state and the crystalline state only takes a nanosecond level, and the refractive index difference between the two states is significant. A fast switch can be achieved by applying a pulsed voltage through an electrode. Compared with traditional thermo-optical and electro-optical effect switches, it has a smaller size, lower power consumption, faster speed, and the process is compatible with CMOS circuits and is easy to integrate.

[0021] 2. The present invention ingeniously integrates the phase change material switch and the optical phased array waveguide on a single chip, and realizes the dynamic control of the emission state and scanning mode of the phased array through the spectral splitting control of the switch. Compared with the traditional system, the chip size is reduced by 1-2 orders of magnitude, the weight is reduced by 2-3 orders of magnitude, and the power consumption is reduced by 1-2 orders of magnitude, greatly improving the integration degree. This on-chip integrated optoelectronic hybrid system has the advantages of small volume, light weight, low power consumption, high intelligence, etc., and conforms to the development trend of microsystems and integrated circuits.

[0022] 3. The present utility model integrates two different optical phased arrays (end-face emission type and grating emission type) on the same chip, and realizes flexible switching of working modes through a phase change material switch. The end-face emission type OPA realizes horizontal scanning, and the grating emission type OPA realizes vertical scanning. By means of the switch, the two modules can be selectively connected to achieve hybrid scanning. Compared with a single scanning method, the present utility model greatly expands the application scenarios of the OPA, improves the flexibility of the system, and can meet the multi-dimensional imaging and detection requirements in complex environments.

[0023] 4. The on-chip optical phased array formed by the present utility model has the ability of rapid reconfiguration of the beam direction and shape. By thermo-optically regulating the phases of the waveguides, the dynamic change of the beam pointing and shape can be realized in the millisecond level. Compared with the traditional mechanical beam scanning, the response speed is increased by 2-3 orders of magnitude, realizing continuous scanning and random jumping of the beam, and endowing the system with stronger environmental adaptability. At the same time, without mechanical inertia and wear, the system is more stable and reliable.

[0024] 5. The present utility model has excellent scalability, demonstrating the integration of larger-scale switch arrays and waveguide arrays, further improving the number of channels and the degree of regulation freedom. This scalable characteristic enables the performance and functions of the system to be continuously upgraded with the improvement of requirements and process levels, and it is a future-oriented technical solution. At the same time, this solution is not limited to silicon-based, and can also be extended to different substrate materials such as gallium arsenide, gallium nitride, and quartz to adapt to applications in different wavelength bands.

[0025] 6. The present utility model is based on the industrialization requirements of optoelectronic integration, and the process is completely compatible with the existing CMOS process. It can be mass-produced by using mature micro-nano processing means, and has a clear industrialization path and application prospects. Based on this system, a new generation of optoelectronic system products with small volume, light weight, low power consumption, intelligence, and multi-functions can be developed, which have broad application potential in the fields of optical communication, lidar, three-dimensional imaging, biological detection, etc., and can significantly improve the performance of related optoelectronic devices and promote the upgrading of the industry.

[0026] 7. The present utility model opens up a new way for the application of phase change materials in silicon-based optoelectronic devices. Traditionally, the combination of silicon-based optoelectronic devices and phase change materials mainly focuses on storage, computing, etc. The present utility model introduces it into optical switches and optical phased arrays, and reveals its excellent characteristics in fast signal regulation and beam control. This not only broadens the application scope of phase change materials in the field of silicon-based optoelectronics, but also provides a new idea for the construction of silicon-based on-chip reconfigurable photonic systems. It has important inspiration significance in related theoretical research and experimental exploration.

[0027] In summary, the present utility model realizes the dynamic reconfiguration of the optical phased array on the silicon substrate by using the phase change material GST switch. Through the flexible switching of the working mode, one-dimensional, two-dimensional and even three-dimensional multi-dimensional scanning imaging can be realized. It has high integration, powerful functions and wide applications, representing the development direction of optoelectronic system integration and intelligence, and playing an important role in promoting the technological progress and industrial upgrading of related industries. It also provides a new idea for the development and application of phase change materials in the field of photonics. The implementation of the present utility model will significantly improve the performance and functions of the silicon-based optoelectronic system, promote the cross-integration of microwave photonics technology and phase change material technology, and have important value in both theoretical research and practical applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments of the present utility model. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0029] Figure 1 is a side view of the ultrafast optical switch heterogeneous integrated silicon nitride module on the silicon substrate provided in the embodiment of the present utility model;

[0030] Figure 2 is a side view of the optical phased array silicon nitride module on the silicon substrate provided in the embodiment of the present utility model;

[0031] Figure 3 is an axonometric view of the ultrafast optical switch heterogeneous integrated silicon nitride module on the silicon substrate provided in the embodiment of the present utility model;

[0032] Figure 4 is a top view of the n4 layer of the optical phased array heterogeneous integrated silicon nitride module on the silicon substrate provided in the embodiment of the present utility model;

[0033] Figure 5 is a top view of the grating structure of the grating-emitting optical phased array silicon nitride module on the optical substrate provided in the embodiment of the present utility model.

[0034] The symbol descriptions are as follows:

[0035] n4, silicon nitride layer; n2, buried oxide layer of silicon dioxide; n1, silicon substrate; n3, phase change material heterogeneous layer; n5, metal electrode layer 1, optical switch module; 2, end-face emitting optical phased array; 3, grating-emitting optical phased array; 1-1, first electrode; 1-2, second electrode; 1-3, third electrode; 2-1, 2-2, phase change material heterogeneous integrated silicon nitride waveguide. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] As Figure 1 shown, the optical switch controls the optical phased array. The ultrafast optical switch heterogeneous integrated silicon nitride module on the silicon substrate is mainly divided into five parts. n1 is the silicon-based bottom layer, n2 is the buried oxide layer of silicon dioxide, n3 is the phase change material layer, n4 is the silicon nitride layer, and n5 is the gold electrode layer. The height of the silicon-based n1 is greater than the height of the buried oxide layer of silicon dioxide n2, the height of the buried oxide layer of silicon dioxide n2 is greater than the height of the silicon nitride layer n4, and the height of the silicon nitride layer n4 is greater than the height of the phase change material layer n3.

[0038] The structure of the silicon nitride layer n4 is as Figure 4 shown, and mainly includes a phase change material heterogeneous integrated optical switch 1, an end-face emitting optical phased array 2 and several waveguides, a grating emitting optical phased array 3 and several waveguides.

[0039] First electrodes 1-2, second electrodes 1-2 and third electrodes 1-3 are arranged on both sides of the long arm of the silicon nitride Mach-Zehnder interferometer. The first electrodes 1-1 and third electrodes 1-3 are used to connect to the positive pole of the power supply, and the second electrodes 1-2 are used to connect to the negative pole of the power supply.

[0040] As Figure 2 shown, the optical phased array heterogeneous integrated silicon nitride module on the silicon substrate is mainly divided into three layers, which are the n1 layer, n2 layer, and n4 layer from bottom to top. Among them, the n1 layer is the silicon substrate, the n2 layer is the buried oxide layer of silicon dioxide, and the n4 layer is the silicon nitride layer. The height of the silicon substrate n1 is greater than the height of the buried oxide layer of silicon dioxide n2, and the height of the buried oxide layer of silicon dioxide n2 is greater than the height of the silicon nitride layer n4.

[0041] The materials of all components (i.e., each waveguide, Mach-Zehnder interferometer, and optical phased array) in the silicon nitride layer n4 are all silicon nitride. Moreover, the heights of all waveguides, Mach-Zehnder interferometers, and optical phased arrays are the same. The height range of each component in the silicon nitride layer n4 is 0.5 μm. And the thickness of the silicon substrate n1 (i.e., Figure 1 the height of the n1 layer) is 500 μm, and the thickness of the buried oxide layer of silicon dioxide n2 (i.e., Figure 1 the height of the n2 layer) ranges from 2 μm. That is, the thickness of the silicon substrate n1 is greater than the thickness of the buried oxide layer of silicon dioxide n2, the thickness of the buried oxide layer of silicon dioxide n2 is greater than the thickness of the silicon nitride layer n4 (i.e., the height of the silicon nitride layer n4), and the thickness of the silicon nitride layer n4 is greater than the thickness of the phase change material heterogeneous layer n3 (i.e.,Figure 1 The height of the n3 layer).

[0042] The silicon nitride layer n4 includes: an optical switch module 1 for regulating optical splitting, a heterogeneous integrated silicon nitride waveguide module 2 for controlling end-face-emitting OPA, and a heterogeneous integrated silicon nitride waveguide module 3 for controlling grating-emitting OPA. The system uses the optical switch module to perform controllable optical splitting adjustment on the input light, and the scanning mode and emission mode of the optical phased array can be selected in the latter two modules.

[0043] The optical switch module 1 includes a Mach-Zehnder interferometer, with a first electrode 1-1, a second electrode 1-2, and a third electrode 1-3 arranged on both sides of its long arm. The first electrode 1-1 and the third electrode 1-3 are connected to the positive pole of the power supply, and the second electrode 1-2 is connected to the negative pole of the power supply. A voltage is applied to the phase change material heterogeneous layer n3 through the electrodes to cause the phase change material to change phase, changing the phase difference of the interference arms, and realizing 0 / 1 signal splitting regulation of the subsequent optical path.

[0044] The heterogeneous integrated silicon nitride waveguide module 2 for end-face-emitting OPA includes N parallel heterogeneous integrated silicon nitride waveguides (2-1, 2-2,...), which serve as the emission array elements of the optical phased array, realize light convergence, and perform horizontal direction scanning imaging on the target.

[0045] The grating-emitting optical phased array module 3 includes N parallel heterogeneous integrated silicon nitride waveguides, and a grating structure is arranged at the emission end of each waveguide to diffract the incident light, enabling the light to be emitted perpendicular to the chip plane, and realizing a vertical direction scanning mode different from end-face emission.

[0046] The phase change material heterogeneous layer n3 uses GST phase change material, and the refractive index difference between the amorphous state and the crystalline state is n. A voltage U is applied to GST through the electrodes to cause GST to change from the amorphous state to the crystalline state, and the refractive indices between the two states satisfy the following relationship:

[0047]

[0048] Where is the refractive index of the GST crystalline state, is the refractive index of the GST amorphous state, is the material constant, is the pulse duration.

[0049] The voltage range applied between the first electrode 1-1 and the second electrode 1-2 and between the second electrode 1-2 and the third electrode 1-3 is 0~30V.

[0050] In the silicon nitride layer n4, the optical switch module 1, the hetero-integrated silicon nitride waveguide module 2 of the end-face-emitting OPA, and the grating-emitting optical phased array module 3 are interconnected through silicon nitride waveguides to achieve low-loss optical interconnection between different modules.

[0051] The above control method for the optical switch to control the optical phased array includes the following steps:

[0052] Step 1: Coupling the light output by the laser into the input waveguide of the chip through an optical fiber;

[0053] Step 2: By applying a voltage pulse to the optical switch module 1, the GST of the phase change material hetero-layer n3 is reversibly transformed between the amorphous state and the crystalline state, changing the refractive index and phase difference of the interference arms, controlling the optical power distribution ratio, and coupling the light to the hetero-integrated silicon nitride waveguide module 2 of the end-face-emitting OPA or the grating-emitting optical phased array module 3;

[0054] Step 3: When the light is coupled to the hetero-integrated silicon nitride waveguide module 2 of the end-face-emitting OPA, the light is transmitted in N parallel hetero-integrated silicon nitride waveguides 2-1, 2-2,... to form emission array elements, and finally emitted from the waveguide end face to achieve horizontal scanning;

[0055] Step 4: When the light is coupled to the grating-emitting optical phased array module 3, the light is transmitted in N parallel hetero-integrated silicon nitride waveguides and finally emitted from the grating structure above the waveguide to achieve vertical scanning;

[0056] Step 5: By controlling the pulse voltage parameters of the optical switch module 1, the end-face emission mode, the vertical emission mode, or the dynamic switching between the two emission modes is achieved to meet the scanning imaging requirements in different directions.

[0057] The working principle of the optical switch to control the optical phased array is as follows:

[0058] An external light source enters the ultrafast optical switch hetero-integrated silicon nitride module on the silicon substrate of Module 1 through end-face coupling. It consists of two Mach-Zehnder interferometers, which respectively control the optical phased array Modules 2 and 3. By hetero-integrating the phase change material GST on the long arms of the Mach-Zehnder interferometers, the GST series alloys are the most mature phase change materials, with advantages such as fast crystallization rate, large changes in resistance and refractive index between the amorphous and crystalline states, and good reversibility between the amorphous and crystalline states. The crystallization temperature of the GST material is about 168 °C, and the crystallization time can reach the nanosecond level, which is suitable for ultrafast optical switch applications. Since the refractive index difference between the crystalline and amorphous states of the GST material is 1.4, and by depositing gold electrodes, an applied voltage can provide the phase change material with sufficient energy for phase change. Since the change in the refractive index of the GST layer will break the total reflection condition of the waveguide, specific waveguides will be unable to transmit light, thereby changing the position of the overall outgoing light of the chip, making the refractive index of the phase change material hetero-integrated silicon nitride hybrid waveguide change, thereby controlling the phase difference between the two arms. Using the interference effect, the optical path can be selectively guided into the optical phased array Modules 3 and 4 with different outgoing modes. By controlling the phase difference well, light can be made to enter only Module 2 to achieve an optical phased array with end-face emission on the silicon substrate, or light can be made to enter only Module 3 to achieve an optical phased array with grating emission on the silicon substrate. Using the grating structure enables light to be emitted in the direction perpendicular to the chip, or light can enter Modules 2 and 3 simultaneously, and the light is finally emitted from the end-face and perpendicularly respectively, so that a spatial scan can be performed to obtain more spatial information.

[0059] Compared with the prior art, the tunable wide-spectrum multi-light source system on the silicon substrate of the present utility model has the following advantages:

[0060] (1) By regulating the voltage of the optical switch module, a selectable optical phased array emission mode can be achieved, and an optical phased array with vertical emission or an optical phased array with end-face emission can be generated respectively, having the advantage of spatial scanning ability.

[0061] (2) This system is integrated on a silicon chip. In actual production, it is easy to mass-produce, having the advantages of small volume, high flexibility, simple structure, and being convenient to be compatible with other systems.

[0062] (3) The GST material has the advantages of fast crystallization rate, large changes in resistance and refractive index between the amorphous and crystalline states, and good reversibility between the amorphous and crystalline states.

[0063] The above description is not a limitation of the present utility model, nor is the present utility model limited to the above examples. Those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present utility model, and should all be included within the protection scope of the present utility model.

Claims

1. An optical switch controls an optical phased array, characterized in that, Comprising: A silicon substrate (n1), a buried silicon dioxide layer (n2), and a silicon nitride layer (n4). The buried silicon dioxide layer (n2) is disposed on the upper surface of the silicon substrate (n1), the silicon nitride layer (n4) is disposed on the upper surface of the buried silicon dioxide layer (n2), a phase change material heterolayer (n3) is disposed on the upper surfaces of the buried silicon dioxide layer (n2) and the silicon nitride layer (n4), and a metal electrode layer (n5) is disposed on the upper surface of the phase change material heterolayer (n3); The silicon nitride layer (n4) includes: an optical switch module (1) for regulating optical splitting, a heterogeneous integrated silicon nitride waveguide module (2) for controlling end-face-emitting OPA, and a heterogeneous integrated silicon nitride waveguide module (3) for controlling grating-emitting OPA. The silicon nitride layer (n4) uses the optical switch module (1) to perform controllable optical splitting adjustment on the input light, and the latter two modules can select the scanning mode and emission mode of the optical phased array; The optical switch module (1) includes a Mach-Zehnder interferometer, with a first electrode (1-1), a second electrode (1-2), and a third electrode (1-3) disposed on both sides of its long arm. The first electrode (1-1) and the third electrode (1-3) are connected to the positive pole of the power supply, the second electrode (1-2) is connected to the negative pole of the power supply, and a voltage is applied to the phase change material heterolayer (n3) through the electrodes to cause the phase change material to change phase, changing the phase difference of the interference arms, and realizing 0 / 1 signal splitting regulation of the rear optical path; The heterogeneous integrated silicon nitride waveguide module (2) for end-face-emitting OPA includes N parallel heterogeneous integrated silicon nitride waveguides (2-1, 2-2,...), serving as the emission array elements of the optical phased array, realizing light beam convergence, and performing horizontal direction scanning imaging on the target.

2. The optical switch-controlled optical phased array according to claim 1, wherein , The heterogeneous integrated silicon nitride waveguide module (3) for grating-emitting OPA includes N parallel heterogeneous integrated silicon nitride waveguides, and a grating structure is disposed at the emission end of each waveguide to diffract the incident light, enabling the light to be emitted perpendicular to the chip plane, and realizing a vertical direction scanning mode different from that of end-face emission.

3. The optical switch-controlled optical phased array according to claim 1, wherein , The thickness of the silicon substrate (n1) is greater than the thickness of the buried silicon dioxide layer (n2), the thickness of the buried silicon dioxide layer (n2) is greater than the thickness of the silicon nitride layer (n4), and the thickness of the silicon nitride layer (n4) is greater than the thickness of the phase change material heterolayer (n3).

4. The optical switch-controlled optical phased array according to claim 3, wherein , The thickness of the silicon substrate (n1) is 500 μm, the thickness of the buried silicon dioxide layer (n2) is 2 μm, the thickness of the silicon nitride layer (n4) is 0.5 μm, and the thickness of the phase change material heterolayer (n3) is 0.1 μm.

5. The optical switch-controlled optical phased array according to claim 1, wherein , The phase change material heterolayer (n3) uses a GST phase change material, and the refractive index difference between the amorphous state and the crystalline state is n. By applying a voltage U to the GST through the electrodes, the GST is changed from the amorphous state to the crystalline state, and the refractive indices between the two states satisfy the following relationship: Among them, is the crystalline refractive index of GST, is the amorphous refractive index of GST, is the material constant, is the pulse duration.

6. The optical switch-controlled optical phased array according to claim 2, wherein , The voltage range applied between the first electrode (1-1) and the second electrode (1-2), and between the second electrode (1-2) and the third electrode (1-3) is 0 to 30 V.

7. The optical switch-controlled optical phased array according to claim 1, wherein , in the silicon nitride layer (n4), the optical switch module (1), the hetero-integrated silicon nitride waveguide module (2) of the end-face-emitting OPA, and the hetero-integrated silicon nitride waveguide module (3) of the grating-emitting OPA are interconnected through silicon nitride waveguides to achieve low-loss optical interconnection between different modules.

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