A C-band silicon-based heterogeneous integrated light-emitting device and its fabrication method

Abstract

This invention relates to a C-band silicon-based heterogeneous integrated optical emitting device and its fabrication method, belonging to the field of optical device technology. The invention utilizes a silicon-based photonic waveguide layer with vertical evanescent wave coupling to a first and second waveguide layer, respectively, to form a Si / InP mode converter while maintaining mode matching. The silicon-based photonic waveguide layer is optically interconnected with the InP waveguide layer via the Si / InP mode converter through vertical evanescent wave coupling, thereby achieving functions such as light generation, detection, and amplification. The invention designs the InP waveguide layer as a two-layer cascaded waveguide structure, which can more effectively improve coupling efficiency and reduce end-face parasitic reflections.

Description

Technical Field

[0001] This invention relates to the field of optical device technology, and in particular to a C-band silicon-based heterogeneous integrated light emitting device and its fabrication method. Background Technology

[0002] Silicon photonics technology is a photonic integration technology based on silicon materials and utilizing existing CMOS processes to manufacture optical devices. Photonic integration technology is considered a core technology for overcoming the two major technological bottlenecks of speed and energy consumption faced by next-generation information networks. Compared to traditional integrated circuit chips, silicon photonic chips based on laser photonics technology have significant advantages such as low cost, low power consumption, and high bandwidth. Furthermore, silicon photonic chips do not require extreme miniaturization of process dimensions, and their manufacturing processes are not as stringent as those for electronic chips. This reduces reliance on advanced processes and alleviates, to some extent, the bottlenecks restricting current chip development. With the rapid development of modern information technology, the explosive growth of global data traffic is foreseeable, placing higher demands on data transmission speeds and processing. The development of services such as 5G, AI, LiDAR, and data centers has generated rapidly increasing data traffic, bringing a series of challenges to the transmission of optical networks at all levels. The bandwidth requirements of data center optical modules have increased from 100G and 200G to the current 800G and 1.6T era. To address the issue of how to increase transmission speed while reducing energy consumption and loss, the industry is paying further attention to photonic integration technology.

[0003] Currently, silicon-based photonics platforms suffer from problems such as lattice mismatch and thermal expansion coefficient mismatch between silicon and InP and lithium niobate materials, and there is also a refractive index mismatch between silicon and InP and lithium niobate materials. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a C-band silicon-based heterogeneous integrated light emitting device and its fabrication method.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] In a first aspect, the present invention provides a C-band silicon-based heterogeneous integrated optical emitting device, comprising a silicon-based photonic waveguide layer, an InP waveguide layer, a lithium niobate waveguide layer, and a first insulating layer. The first insulating layer encapsulates the side and top surfaces of the silicon-based photonic waveguide layer. The InP waveguide layer and the lithium niobate waveguide layer are disposed on the first insulating layer. The InP waveguide layer includes a first waveguide layer and a second waveguide layer disposed sequentially from bottom to top. The silicon-based photonic waveguide layer is optically interconnected with the first waveguide layer by vertical evanescent wave coupling. The silicon-based photonic waveguide layer is optically interconnected with the second waveguide layer by vertical evanescent wave coupling. The silicon-based photonic waveguide layer is optically interconnected with the lithium niobate waveguide layer by vertical evanescent wave coupling.

[0007] Preferably, the first waveguide layer includes a first straight waveguide and a first tapered waveguide disposed on both sides of the first straight waveguide; the second waveguide layer includes a second straight waveguide and a second tapered waveguide disposed on both sides of the second straight waveguide;

[0008] The lithium niobate waveguide layer is provided with a lithium niobate straight waveguide and two lithium niobate tapered waveguides, with the two lithium niobate tapered waveguides respectively disposed on both sides of the lithium niobate straight waveguide.

[0009] More preferably, the silicon-based photonic waveguide layer includes four silicon-based tapered waveguides arranged sequentially, each silicon-based tapered waveguide having a silicon-based straight waveguide connected to its tail end. The first two silicon-based tapered waveguides overlap with the first and second straight waveguides respectively in the optical signal transmission direction, and the silicon-based straight waveguides connected to the first two silicon-based tapered waveguides overlap with the first and second tapered waveguides respectively in the optical signal transmission direction. The last two silicon-based tapered waveguides overlap with two lithium niobate tapered waveguides in a one-to-one correspondence in the optical signal transmission direction.

[0010] Preferably, the thickness of the silicon-based photonic waveguide layer is no greater than 400 nm.

[0011] Preferably, the first waveguide layer is an n-InP layer.

[0012] Preferably, the second waveguide layer is composed of a quantum well layer, a p-InP layer and a p-Contact layer arranged sequentially from bottom to top.

[0013] More preferably, an N-metal layer and a cladding are disposed on the first waveguide layer, and the side surfaces of the first waveguide layer, quantum well layer, p-InP layer and p-Contact layer are wrapped with cladding, and a P-metal layer is disposed on the p-Contact layer.

[0014] Preferably, a metal contact layer is disposed above the lithium niobate waveguide layer, and a cladding layer is disposed between the lithium niobate waveguide layer and the metal contact layer.

[0015] Secondly, the present invention provides a method for fabricating a C-band silicon-based heterogeneous integrated optical emitting device as described in the first aspect, comprising the following steps:

[0016] S1. Fabricate a silicon-based photonic waveguide layer on a substrate layer, including silicon-based straight waveguides, silicon-based tapered waveguides, and silicon-based grating passive optical devices;

[0017] S2. Prepare a first insulating layer on the upper surface of the silicon-based photonic waveguide layer;

[0018] S3. The InP epitaxial layer with substrate and the lithium niobate thin film device layer with substrate are transferred onto the first insulating layer with the substrate facing upward. The substrate is removed by substrate thinning and wet etching. Cladding layers are prepared on the InP epitaxial layer and the lithium niobate thin film device layer respectively.

[0019] S4. Fabricate InP waveguide layer, lithium niobate waveguide layer, P metal layer, N metal layer and metal contact layer.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] This invention utilizes a silicon-based photonic waveguide layer to form a Si / InP mode converter by perpendicularly evanescently coupling a first waveguide layer and a second waveguide layer, respectively, while maintaining mode matching. The silicon-based photonic waveguide layer is optically interconnected with the InP waveguide layer via the Si / InP mode converter through perpendicular evanescently coupling, thereby achieving functions such as light generation, detection, and amplification. This invention designs the InP waveguide layer as a two-layer cascaded waveguide structure, which can more effectively improve coupling efficiency and reduce end-face parasitic reflections. Attached Figure Description

[0022] Figure 1 A planar schematic diagram of the C-band silicon-based heterogeneous integrated optical emitting device provided by the present invention;

[0023] Figure 2 This is a cross-sectional view of the region where the InP waveguide layer is located, as provided in this invention.

[0024] Figure 3 This is a cross-sectional view of the region where the lithium niobate waveguide layer is located, as provided in this invention.

[0025] In the figure, 1-silicon-based photonic waveguide layer, 11-silicon-based straight waveguide, 12-silicon-based tapered waveguide, 2-InP waveguide layer, 21-first waveguide layer, 211-first straight waveguide, 212-second tapered waveguide, 22-second waveguide layer, 221-second straight waveguide, 222-second tapered waveguide, 223-quantum well layer, 224-p-InP layer, 225-p-Contact layer, 3-lithium niobate waveguide layer, 31-lithium niobate straight waveguide, 32-lithium niobate tapered waveguide, 4-first insulating layer, 5-substrate layer, 51-substrate layer, 52-second insulating layer, 6-cladding layer, 7-P metal layer, 8-N metal layer, 9-metal contact layer. Detailed Implementation

[0026] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0027] Please see Figures 1-3 In a first aspect, the present invention provides a C-band silicon-based heterogeneous integrated optical emitting device, comprising a silicon-based photonic waveguide layer 1, an InP waveguide layer 2, a lithium niobate waveguide layer 3, and a first insulating layer 4. The first insulating layer 4 encapsulates the side and top surfaces of the silicon-based photonic waveguide layer 1. The InP waveguide layer 2 and the lithium niobate waveguide layer 3 are disposed on the first insulating layer 4. The InP waveguide layer 2 includes a first waveguide layer 21 and a second waveguide layer 22 disposed sequentially from bottom to top. The silicon-based photonic waveguide layer 1 and the first waveguide layer 21 are optically interconnected by vertical evanescent wave coupling. The silicon-based photonic waveguide layer 1 and the second waveguide layer 22 are optically interconnected by vertical evanescent wave coupling. The silicon-based photonic waveguide layer 1 and the lithium niobate waveguide layer 3 are optically interconnected by vertical evanescent wave coupling.

[0028] It should be noted that, in this invention, the width refers to Figure 1 The dimension in the W direction, the length refers to Figure 1 The dimension in the L direction.

[0029] In one embodiment, the first waveguide layer 21 includes a first straight waveguide 211 and a first tapered waveguide 212 disposed on both sides of the first straight waveguide 211; the second waveguide layer 22 includes a second straight waveguide 221 and a second tapered waveguide 222 disposed on both sides of the second straight waveguide 221.

[0030] The lithium niobate waveguide layer 3 is provided with a lithium niobate straight waveguide 31 and two lithium niobate tapered waveguides 32, with the two lithium niobate tapered waveguides 32 respectively disposed on both sides of the lithium niobate straight waveguide 31;

[0031] The silicon-based photonic waveguide layer 1 includes four silicon-based tapered waveguides 12 arranged sequentially. Each silicon-based tapered waveguide 12 is connected to a silicon-based straight waveguide 11 at its tail end. The first straight waveguide 211 and the second straight waveguide 221 overlap with the first two silicon-based tapered waveguides 12 in the optical signal transmission direction. The silicon-based straight waveguide 11 connected to the first two silicon-based tapered waveguides 12 overlaps with the first tapered waveguide 212 and the second tapered waveguide 222 in the optical signal transmission direction, respectively. The last two silicon-based tapered waveguides 12 overlap with two lithium niobate tapered waveguides 32 in a one-to-one correspondence in the optical signal transmission direction.

[0032] In this invention, the silicon-based straight waveguide 11 is perpendicularly evanescently coupled to the first waveguide layer 21 and the second waveguide layer 22, forming a Si / InP mode converter while maintaining mode matching. The silicon-based photonic waveguide layer 1 is optically interconnected with the InP waveguide layer 2 via the Si / InP mode converter in a perpendicular evanescent coupling manner, thereby realizing functions such as light generation, detection, and amplification. This invention designs the InP waveguide layer 2 as a two-layer cascaded waveguide structure. This structure can be efficiently coupled to the thinner silicon-based photonic waveguide layer 1, reducing end-face parasitic reflections.

[0033] In this invention, the corresponding silicon-based tapered waveguide 12 and lithium niobate tapered waveguide 32 are vertically evanescently coupled to form a Si / LN mode converter and maintain mode matching. The silicon-based photonic waveguide layer 1 is optically interconnected with the lithium niobate waveguide layer 3 through the Si / LN mode converter in a vertical evanescently coupled manner, thereby realizing the high-speed linear optical modulation function.

[0034] The optical emitting device described in this invention can operate in the C-band.

[0035] Specifically, the width of the silicon-based straight waveguide 11 is 500–5000 nm.

[0036] Specifically, the width of the first straight waveguide 211 is 2000-7000 nm; the width of the tip of the first tapered waveguide 212 increases linearly from its tail end to its tip end, the width of the tip of the first tapered waveguide 212 is 100-500 nm, the tail end of the first tapered waveguide 212 is connected to the first straight waveguide 211, and the width of the tail end of the first tapered waveguide 212 is equal to the width of the first straight waveguide 211.

[0037] Specifically, the width of the second straight waveguide 221 is 2000–7000 nm; the width of the tip of the second tapered waveguide 222 increases linearly from its tail end to its tip end, the width of the tip of the second tapered waveguide 222 is 100–500 nm, the tail end of the second tapered waveguide 222 is connected to the second straight waveguide 221, and the width of the tail end of the second tapered waveguide 222 is equal to the width of the second straight waveguide 221.

[0038] Specifically, the length of the overlapping region between the first straight waveguide 211 and the corresponding silicon-based tapered waveguide 12 in the optical signal transmission direction is 10 to 50,000 μm (preferably 50 to 500 μm), and the length of the overlapping region between the second straight waveguide 221 and the corresponding silicon-based tapered waveguide 12 in the optical signal transmission direction is 10 to 50,000 μm (preferably 50 to 500 μm).

[0039] The length of the overlapping region (i.e., coupling region) between the first tapered waveguide 212 and the corresponding silicon-based straight waveguide 11 in the optical signal transmission direction is 10 to 50,000 μm (preferably 50 to 500 μm); the length of the overlapping region (i.e., coupling region) between the second tapered waveguide 222 and the corresponding silicon-based straight waveguide 11 in the optical signal transmission direction is 10 to 50,000 μm (preferably 20 to 200 μm).

[0040] The length of the overlapping region (i.e. coupling region) between the lithium niobate tapered waveguide 32 and the corresponding silicon-based tapered waveguide 12 in the optical signal transmission direction is 10 to 50,000 μm (preferably 20 to 100 μm).

[0041] The inventors discovered that by controlling the length of each overlapping region within the above-mentioned preferred range, the coupling efficiency between the InP waveguide layer 2 and the lithium niobate waveguide layer 3 and the silicon-based photonic waveguide layer 1 is higher.

[0042] Specifically, the first waveguide layer 21 is an n-InP layer. The second waveguide layer 22 is composed of a quantum well layer 223, a p-InP layer 224, and a p-Contact layer 225 arranged sequentially from bottom to top.

[0043] An N-metal layer 8 and a cladding layer 6 are disposed on the first waveguide layer 21. The side surfaces of the first waveguide layer 21, quantum well layer 223, p-InP layer 224 and p-Contact layer 225 are covered with the cladding layer 6. A P-metal layer is disposed on the p-Contact layer 225.

[0044] A metal contact layer 9 is disposed above the lithium niobate waveguide layer 3, and a cladding layer 6 is disposed between the lithium niobate waveguide layer 3 and the metal contact layer 9.

[0045] The material of the cladding layer 6 can be silicon dioxide or benzocyclobutene, and the thickness of the cladding layer 6 is 1 to 3 μm.

[0046] Specifically, the width of the lithium niobate straight waveguide 31 is 500–5000 nm.

[0047] Specifically, the width of the silicon-based tapered waveguide 12 increases linearly from its tip to its tail, with a tip width of 100–300 nm. The tail of the silicon-based tapered waveguide 12 connects to the silicon-based straight waveguide 11, and the width of the tail of the silicon-based tapered waveguide 12 is equal to the width of the silicon-based straight waveguide 11. Similarly, the width of the lithium niobate tapered waveguide 32 increases linearly from its tip to its tail, with a tip width of 100–500 nm. The tail of the lithium niobate tapered waveguide 32 connects to the lithium niobate straight waveguide 31, and the width of the tail of the lithium niobate tapered waveguide 32 is equal to the width of the lithium niobate straight waveguide 31. The tip of the lithium niobate tapered waveguide 32 faces in the opposite direction to the tip of its corresponding overlapping silicon-based tapered waveguide 12.

[0048] Specifically, the thickness of the first waveguide layer 21 is 50–300 nm, the thickness of the quantum well layer 223 is 100–500 nm, the thickness of the p-InP layer 224 is 1500–2000 nm, the thickness of the p-Contact layer 225 is 50–300 nm, the thickness of the silicon-based photonic waveguide layer 1 is no more than 400 nm, the thickness of the silicon-based straight waveguide 11 is 220–400 nm, the thickness of the silicon-based tapered waveguide 12 is 220–400 nm, the total thickness of the lithium niobate waveguide layer 3 is 360–600 nm, the thickness of the lithium niobate straight waveguide 31 is 180–300 nm, and the thickness of the lithium niobate tapered waveguide 32 is 180–300 nm.

[0049] In this invention, the thicknesses of the silicon-based straight waveguide 11 and the silicon-based tapered waveguide 12 can each be independently selected from a range of 220 nm, 250 nm, 300 nm, 350 nm, or two sets of values ​​thereon. This invention designs the InP waveguide layer 2 as a two-layer cascaded waveguide structure consisting of a first waveguide layer 21 and a second waveguide layer 22. This structure can efficiently couple with the silicon-based photonic waveguide layer 1, which has a thickness of less than 400 nm, reducing end-face parasitic reflections.

[0050] In one embodiment, the first insulating layer 4 is made of silicon oxide.

[0051] In one embodiment, the C-band silicon-based heterogeneous integrated optical emitting device further includes a substrate layer 5, which includes a second insulating layer 51 and a substrate layer 52, with the silicon-based photonic waveguide layer 1, the second insulating layer 51, and the substrate layer 52 arranged sequentially from top to bottom.

[0052] Specifically, the material of the second insulating layer 51 can be silicon dioxide.

[0053] Specifically, the substrate 52 can be made of silicon.

[0054] Secondly, the present invention provides a method for fabricating a C-band silicon-based heterogeneous integrated optical emitting device as described in the first aspect, comprising the following steps:

[0055] S1. A silicon-based photonic waveguide layer 1 with a silicon-based straight waveguide 11, a silicon-based tapered waveguide 12, and a silicon-based grating passive optical device (not shown in the figure) is fabricated on the substrate layer 5.

[0056] S2. A first insulating layer 4 is prepared on the substrate layer 5 and the silicon-based photonic waveguide layer 1;

[0057] S3. The InP epitaxial layer with substrate and the lithium niobate thin film device layer with substrate are transferred to the side of the first insulating layer 4 away from the silicon-based photonic waveguide layer 1 with the substrate facing upward. The substrate is removed by substrate thinning and wet etching. Cladding layers are prepared on the InP epitaxial layer and the lithium niobate thin film device layer respectively.

[0058] S4. Prepare InP waveguide layer 2, lithium niobate waveguide layer 3, P metal layer 7, N metal layer 8 and metal contact layer 9.

[0059] Step S4 includes:

[0060] A. Open a window in the cladding of the lithium niobate thin film device layer to expose the lithium niobate thin film device layer. Process the exposed lithium niobate thin film device layer to form a lithium niobate waveguide layer 3. Deposit a silicon oxide cladding layer on the upper surface of the lithium niobate waveguide layer 3 using thin film deposition technology. Prepare a metal contact layer 9 on the corresponding area of ​​the silicon oxide cladding layer by metal evaporation and lift-off process.

[0061] B. Open a window in the cladding of the InP epitaxial layer to expose the InP epitaxial layer. Process the exposed InP epitaxial layer to form InP waveguide layer 2. Prepare P metal layer 7 and N metal layer 8 on InP waveguide layer 2 by metal evaporation and lift-off process.

[0062] In step S4, step A can be performed first, and a silicon oxide cladding layer can be deposited on the metal contact layer 9 using thin film deposition technology. Then step B can be performed, and a window can be opened in the cladding layer on the metal contact layer 9 to expose the metal contact layer 9.

[0063] In step S4, step B can be performed first, after which a silicon oxide cladding layer is deposited on the P metal layer 7 and the N metal layer 8 using thin film deposition technology. Then, a window is opened in the cladding layer on the P metal layer 7 and the N metal layer 8 to expose the P metal layer 7 and the N metal layer 8.

[0064] In one embodiment, step S2 includes: depositing a silicon dioxide thin film on the substrate layer 5 and the silicon-based photonic waveguide layer 1 using a thin film deposition method, and then polishing the formed silicon dioxide thin film flat using a chemical mechanical polishing technique to form a first insulating layer 4.

[0065] In one embodiment, in step S3, the cladding is prepared by thin film deposition or spin coating. For example, the cladding material is silicon dioxide, which is deposited on the outer surfaces of the InP waveguide layer 2 and the lithium niobate waveguide layer 3 by thin film deposition to form the cladding; or, for example, the cladding material is benzocyclobutene, which is spin-coated on the outer surfaces of the InP waveguide layer 2 and the lithium niobate waveguide layer 3 by spin coating, and then cured to form the cladding.

[0066] In one embodiment, before step S1, the method further includes: preparing a second insulating layer 51 on the upper surface of the substrate layer 52, and preparing a silicon-based photonic waveguide layer 1 on the upper surface of the second insulating layer 51.

[0067] In the description of this invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating the number of technical features indicated. Therefore, a feature defined with "first," "second," and "third" may explicitly or implicitly include at least one of those features. All directional indicators (such as "up" and "down") in this invention are only used to explain the relative positional relationships and movements between components in a specific orientation (as shown in the accompanying drawings). If this specific orientation changes, the directional indicator will also change accordingly.

[0068] In the description of this invention, it should also be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0069] Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A C-band silicon-based heterogeneous integrated optical emitting device, characterized in that, The device includes a silicon-based photonic waveguide layer, an InP waveguide layer, a lithium niobate waveguide layer, and a first insulating layer. The first insulating layer wraps around the side and top surfaces of the silicon-based photonic waveguide layer. The InP waveguide layer and the lithium niobate waveguide layer are disposed on the first insulating layer. The InP waveguide layer includes a first waveguide layer and a second waveguide layer disposed sequentially from bottom to top. The silicon-based photonic waveguide layer is optically interconnected with the first waveguide layer by vertical evanescent wave coupling. The silicon-based photonic waveguide layer is optically interconnected with the second waveguide layer by vertical evanescent wave coupling. The silicon-based photonic waveguide layer is optically interconnected with the lithium niobate waveguide layer by vertical evanescent wave coupling. The first waveguide layer includes a first straight waveguide and a first tapered waveguide disposed on both sides of the first straight waveguide; the second waveguide layer includes a second straight waveguide and a second tapered waveguide disposed on both sides of the second straight waveguide; The lithium niobate waveguide layer is provided with a lithium niobate straight waveguide and two lithium niobate tapered waveguides, with the two lithium niobate tapered waveguides respectively disposed on both sides of the lithium niobate straight waveguide; The silicon-based photonic waveguide layer includes four silicon-based tapered waveguides arranged sequentially. Each silicon-based tapered waveguide is connected to a silicon-based straight waveguide at its tail end. The first two silicon-based tapered waveguides overlap with the first and second straight waveguides in the optical signal transmission direction. The silicon-based straight waveguides connected to the first two silicon-based tapered waveguides overlap with the first and second tapered waveguides in the optical signal transmission direction, respectively. The last two silicon-based tapered waveguides overlap with two lithium niobate tapered waveguides in a one-to-one correspondence in the optical signal transmission direction.

2. The C-band silicon-based heterogeneous integrated optical emitting device as described in claim 1, characterized in that, The thickness of the silicon-based photonic waveguide layer is no greater than 400 nm.

3. The C-band silicon-based heterogeneous integrated optical emitting device as described in claim 1, characterized in that, The first waveguide layer is an n-InP layer.

4. The C-band silicon-based heterogeneous integrated optical emitting device as described in claim 1, characterized in that, The second waveguide layer is composed of a quantum well layer, a p-InP layer and a p-Contact layer arranged sequentially from bottom to top.

5. The C-band silicon-based heterogeneous integrated optical emitting device as described in claim 4, characterized in that, The first waveguide layer is provided with an N metal layer and a cladding layer. The side surfaces of the first waveguide layer, the quantum well layer, the p-InP layer and the p-Contact layer are covered with cladding layers. The p-Contact layer is provided with a P metal layer.

6. The C-band silicon-based heterogeneous integrated optical emitting device as described in claim 1, characterized in that, A metal contact layer is disposed above the lithium niobate waveguide layer.

7. The C-band silicon-based heterogeneous integrated optical emitting device as described in claim 6, characterized in that, A cladding layer is provided between the lithium niobate waveguide layer and the metal contact layer.

8. A method for fabricating a C-band silicon-based heterogeneous integrated optical emitting device as described in any one of claims 1 to 7, characterized in that, Includes the following steps: S1. Fabricate a silicon-based photonic waveguide layer on a substrate layer, including silicon-based straight waveguides, silicon-based tapered waveguides, and silicon-based grating passive optical devices; S2. Prepare a first insulating layer on the upper surface of the silicon-based photonic waveguide layer; S3. The InP epitaxial layer with substrate and the lithium niobate thin film device layer with substrate are transferred onto the first insulating layer with the substrate facing upward. The substrate is removed by substrate thinning and wet etching. Cladding layers are prepared on the InP epitaxial layer and the lithium niobate thin film device layer respectively. S4. Fabricate InP waveguide layer, lithium niobate waveguide layer, P metal layer, N metal layer and metal contact layer.

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