Silicon oxide waveguide optical switch and manufacturing method thereof

Abstract

The invention discloses a silicon oxide waveguide optical switch device and a preparation method thereof, the silicon oxide waveguide optical switch device comprises a waveguide core layer, an upper cladding layer, a lower cladding layer and a heating electrode, a cover plate is arranged on the upper cladding layer and the heating electrode, and a heat dissipation flow channel structure extending downwards into the lower cladding layer is arranged from the upper end face of the cover plate. The heat dissipation flow channel structure is located on the front side of the waveguide core layer and comprises a fluid inflow port, a fluid outflow port and a fluid channel, the fluid inflow port and the fluid outflow port are both cylindrical cavities extending downwards into the cover plate from the upper surface of the cover plate, and the axis of each cylindrical cavity is in the vertical direction; the fluid inlet and the fluid outlet are arranged at an interval left and right, the fluid channel extends from the interior of the cover plate to the interior of the lower cladding, and two ends of the fluid channel are respectively located below the fluid inlet and the fluid outlet and are communicated with the fluid inlet and the fluid outlet in a one-to-one correspondence and up-and-down butt joint manner; the LED lamp has the advantages of being high in heat dissipation efficiency and switching speed.

Description

Technical Field

[0001] The invention relates to a waveguide optical switch, and in particular to a silicon oxide waveguide optical switch and a manufacturing method thereof. Background Art

[0002] Optical switches are core components in the field of optical communications. Their core function is to realize the switching of optical signals between different optical paths. They play an important role in optical network applications such as optical crossbars and optical add-drop multiplexers.

[0003] Existing optical switches usually include silicon-based waveguide optical switches (optical switches based on silicon-based waveguides), polymer waveguide optical switches (optical switches based on polymer waveguides), silicon oxide waveguide optical switches (optical switches based on silicon oxide waveguides) and micro-electromechanical optical switches (optical switches based on micro-electromechanical systems), etc. Among them, silicon oxide waveguide optical switches have the characteristics of low loss, high temperature stability and low cost, and have attracted extensive attention from academia and industry.

[0004] Traditional silicon oxide waveguide optical switches usually include a waveguide core layer for realizing the optical switch function, an upper cladding layer and a lower cladding layer that completely cover the waveguide core layer, and the optical path can be switched by changing the refractive index of the waveguide core layer. The upper cladding layer and the lower cladding layer are both made of silicon oxide material, and the waveguide core layer is made of doped silicon oxide material, and the doped silicon oxide material used to make the waveguide core layer has a refractive index 0.5%-2% higher than that of the silicon oxide material used to make the upper cladding layer and the lower cladding layer. In traditional silicon oxide waveguide optical switches, since the refractive index difference between the waveguide core layer and the upper cladding layer and the lower cladding layer is small, in order to ensure the restriction of the waveguide mode, the thickness of the upper cladding layer and the lower cladding layer is usually large (generally not less than 10μm). The thickness of the upper cladding layer and the lower cladding layer directly affects the heat dissipation efficiency of the silicon oxide waveguide optical switch, and the heat dissipation efficiency directly affects the switching speed of the silicon oxide waveguide optical switch, that is, the greater the thickness, the lower the heat dissipation efficiency and the lower the switching speed. Therefore, the traditional silicon oxide waveguide optical switch has poor heat dissipation efficiency, resulting in a switching speed of only milliseconds, which seriously affects its application in optical interconnection, optical switching and other scenarios. Summary of the invention

[0005] One of the technical problems to be solved by the present invention is to provide a silicon oxide waveguide optical switch with high heat dissipation efficiency and fast switching speed.

[0006] The technical solution adopted by the present invention to solve one of the above technical problems is: a silicon oxide waveguide optical switch device, comprising a waveguide core layer, an upper cladding layer, a lower cladding layer and a heating electrode for realizing an optical switch function, wherein the waveguide core layer is arranged on the upper surface of the lower cladding layer, and the heating electrode is arranged on the upper surface of the upper cladding layer, and is used to heat the waveguide core layer to change its refractive index to realize optical path switching, the materials of the upper cladding layer and the lower cladding layer are both silicon oxide, and the material of the waveguide core layer is doped silicon oxide with a refractive index higher than that of silicon oxide, and a cover plate that completely covers the upper cladding layer and the heating electrode is arranged on the upper surface of the cover plate and extends downward to the lower cladding layer. The heat dissipation flow channel structure inside the layer, the heat dissipation flow channel structure is located on the front side of the waveguide core layer, the heat dissipation flow channel structure includes a fluid inlet, a fluid outlet and a fluid channel, the fluid inlet and the fluid outlet are both starting from the upper surface of the cover plate and extending downward to the cylindrical cavity inside the cover plate, the axis of the cylindrical cavity is along the up and down direction, the fluid inlet and the fluid outlet are arranged at intervals on the left and right, the fluid channel extends from the inside of the cover plate to the inside of the lower cladding, and its two ends are respectively located below the fluid inlet and the fluid outlet, and are connected to the fluid inlet and the fluid outlet in a one-to-one correspondence.

[0007] Compared with the prior art, the advantage of the silicon oxide waveguide optical switch of the present invention is that a cover plate is provided on the upper cladding layer and the heating electrode to completely cover both of them, a heat dissipation flow channel structure is provided from the upper end surface of the cover plate to extend downward to the interior of the lower cladding layer, the heat dissipation flow channel structure is located on the front side of the waveguide core layer, the heat dissipation flow channel structure includes a fluid inlet, a fluid outlet and a fluid channel, the fluid inlet and the fluid outlet are both cylindrical cavities starting from the upper surface of the cover plate and extending downward to the interior of the cover plate, the axis of the cylindrical cavity is in the up-down direction, the fluid inlet and the fluid outlet are arranged at intervals from left to right, and the fluid channel is provided from the interior of the cover plate The silicon oxide waveguide optical switch device extends to the interior of the lower cladding, and its two ends are respectively located below the fluid inlet and the fluid outlet, and are connected to the fluid inlet and the fluid outlet in a one-to-one manner. When the silicon oxide waveguide optical switch is working, the cooling liquid flows into the fluid inlet through the pipeline, then flows through the fluid channel, and finally flows out through the fluid outlet. During the flow of the liquid in the fluid channel, the liquid exchanges heat with the side wall of the fluid channel, and takes away the internal heat of the silicon oxide waveguide optical switch device, thereby realizing the cooling and heat dissipation of the silicon oxide waveguide optical switch device. Therefore, the silicon oxide waveguide optical switch device of the present invention has high heat dissipation efficiency and fast switching speed.

[0008] Furthermore, the fluid channel includes a first flow channel, a second flow channel and a third flow channel, and the first flow channel, the second flow channel and the third flow channel are all square cavities extending downward from the inside of the cover plate to the inside of the lower cladding. The first flow channel is located below the fluid inlet and is connected to the fluid inlet by upper and lower docking. The third flow channel is located below the fluid outlet and is connected to the fluid outlet by upper and lower docking. The second flow channel is located between the first flow channel and the third flow channel and is connected to the first flow channel and the third flow channel respectively. When liquid flows into the fluid inlet through the pipeline, the liquid flows through the first flow channel, the second flow channel and the third flow channel in turn, and finally flows out through the fluid outlet. During the flow of the liquid in the first flow channel, the second flow channel and the third flow channel, the internal heat of the silicon oxide waveguide optical switch device will be taken away, thereby realizing the cooling and heat dissipation of the silicon oxide waveguide optical switch device.

[0009] Furthermore, the material of the cover plate is a polydimethylsiloxane (PDMS) mixture, and the PDMS mixture is formed by uniformly mixing PDMS and a curing agent in a weight ratio of 10:1; the doped silicon oxide is germanium-doped silicon oxide or nitrogen-doped silicon oxide.

[0010] Furthermore, the waveguide core layer is realized by using a Mach-Zehnder interferometer structure.

[0011] Furthermore, the waveguide core layer includes two input waveguides, two 3dB couplers, two phase-shift arm waveguides and two output waveguides, each 3dB coupler has two input ends and two output ends, the two input ends are respectively referred to as the first input end and the second input end, the two output ends are respectively referred to as the first output end and the second output end, the first input end of each 3dB coupler is directly connected to the first output end, the second input end is directly connected to the second output end, the two input waveguides are respectively referred to as the first input waveguide and the second input waveguide, the two 3dB couplers are respectively referred to as the first coupler and the second coupler, the two phase-shift arm waveguides are respectively referred to as the first phase-shift arm waveguide and the second phase-shift arm waveguide, the two output waveguides are respectively referred to as the first output waveguide and the second output waveguide, one end of the first input waveguide and one end of the second input waveguide are both used to access the external The first input waveguide is connected to the first input end of the first coupler, the other end of the second input waveguide is connected to the second input end of the first coupler, the first output end of the first coupler is connected to one end of the first phase-shift arm waveguide, the second output end of the first coupler is connected to one end of the second phase-shift arm waveguide, the other end of the first phase-shift arm waveguide is connected to the first input end of the second coupler, the other end of the second phase-shift arm waveguide is connected to the second input end of the second coupler, the first output end of the second coupler is connected to one end of the first output waveguide, the second output end of the second coupler is connected to one end of the second output waveguide, and the other end of the first output waveguide and the other end of the second output waveguide are both used to output optical signals.

[0012] Furthermore, a heat-insulating groove is provided between the first phase-shifting arm waveguide and the second phase-shifting arm waveguide to avoid heat diffusion and improve thermal tuning efficiency. The heat-insulating groove is a square cavity extending downward from the upper end surface of the upper cladding to the inside of the lower cladding.

[0013] Furthermore, the heating electrode includes a heating resistor wire and two metal electrodes, the heating resistor wire is located directly above the first phase-shift arm waveguide, and the two metal electrodes are respectively connected to both ends of the heating resistor wire for connecting to an external power source to supply power to the heating resistor wire.

[0014] Furthermore, the materials of the two metal electrodes are Al or Au.

[0015] The second technical problem to be solved by the present invention is to provide a method for manufacturing a silicon oxide waveguide optical switch. The silicon oxide waveguide optical switch manufactured by the manufacturing method has high heat dissipation efficiency and fast switching speed.

[0016] The technical solution adopted by the present invention to solve the second technical problem is: a method for manufacturing a silicon oxide waveguide optical switch device, comprising the following steps:

[0017] Step 1, selecting a silicon wafer or a quartz wafer with a silicon oxide material layer having a thickness of more than 10 μm grown on the surface, and the silicon oxide material layer is used as a lower cladding layer;

[0018] Step 2, growing doped silicon oxide on the upper surface of the lower cladding layer to form a doped silicon oxide layer, and performing annealing treatment to eliminate stress;

[0019] Step 3, forming a mask of a waveguide core layer on the doped silicon oxide layer by photolithography, and etching the doped silicon oxide layer by an inductively coupled plasma etching process to form a waveguide core layer;

[0020] Step 4, chemically vapor depositing silicon oxide on the lower cladding layer and the waveguide core layer to form an upper cladding layer;

[0021] Step 5, setting a heating electrode on the upper cladding;

[0022] Step 6, spin-coating photoresist on the upper cladding and the heating electrode, photolithography the photoresist to form a partial structure in which the fluid channel is located in the upper cladding and the lower cladding, and a mask for preventing heat diffusion of the waveguide core layer and improving the thermal tuning efficiency of the heat insulation groove, and completing the etching of the upper cladding and the lower cladding by an inductively coupled plasma etching process to form a partial structure in which the fluid channel is located in the upper cladding and the lower cladding, and the heat insulation groove; the structure obtained at this time is called the first partial structure;

[0023] Step 7, making a mask pattern of a part of the structure where the fluid channel is located on the cover plate, spin-coating photoresist on the base plate, transferring the mask pattern to the photoresist by ultraviolet exposure, and forming a positive mold of a part of the structure where the fluid channel is located on the cover plate after development;

[0024] Step 8, PDMS and curing agent are mixed and stirred evenly in a weight ratio of 10:1, and bubbles are removed in a vacuum to obtain a PDMS mixture;

[0025] Step 9: Wrap the outer edge of the male mold with tin foil, pour the PDMS mixture onto the surface of the male mold, and bake on a heating table to solidify the PDMS mixture;

[0026] Step 10, peeling off the solidified PDMS mixture from the positive mold, at which time the solidified PDMS mixture forms a cover plate, and the portion where the positive mold is peeled off forms a part of the structure where the fluid channel is located on the cover plate;

[0027] Step 11: Use a puncher to punch holes on the cover plate to form a fluid inlet and a fluid outlet connected to the fluid channel. The structure obtained at this time is called the second part structure;

[0028] Step 12: align and bond the second partial structure to the first partial structure to obtain a silicon oxide waveguide optical switch device.

[0029] Compared with the prior art, the manufacturing method of the silicon oxide waveguide optical switch of the present invention has the advantage that the silicon oxide waveguide optical switch device with a heat dissipation flow channel structure is prepared by combining the etching process and the deposition process, and the heat dissipation flow channel structure includes a fluid inlet, a fluid outlet and a fluid channel, and the fluid inlet and the fluid outlet are both cylindrical cavities starting from the upper surface of the cover plate and extending downward to the inside of the cover plate, and the axis of the cylindrical cavity is along the up-down direction, and the fluid inlet and the fluid outlet are arranged at intervals on the left and right, and the fluid channel extends from the inside of the cover plate to the inside of the lower cladding, and its two ends are respectively located at the fluid flow Below the inlet and the fluid outflow outlet, the fluid inlet and the fluid outflow outlet are connected and connected one by one with each other. When the silicon oxide waveguide optical switch is working, the cooling liquid flows into the fluid inlet through the pipeline, then flows through the fluid channel, and finally flows out through the fluid outflow outlet. During the flow of the liquid in the fluid channel, the liquid exchanges heat with the side wall of the fluid channel, which will take away the internal heat of the silicon oxide waveguide optical switch device, thereby realizing the cooling and heat dissipation of the silicon oxide waveguide optical switch device. Therefore, the silicon oxide waveguide optical switch manufactured by the manufacturing method of the silicon oxide waveguide optical switch device of the present invention has high heat dissipation efficiency and fast switching speed.

[0030] Furthermore, the photoresist in step 7 is SU8 photoresist, and the thickness of the photoresist is 40 μm. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A top view (internal structure perspective) of the silicon oxide waveguide optical switch device of the present invention;

[0032] Figure 2 for Figure 1 Sectional view along section 1;

[0033] Figure 3 for Figure 1 Sectional view along section 2;

[0034] Figure 4 It is a flowchart of the first part of the method for manufacturing the silicon oxide waveguide optical switch device of the present invention;

[0035] Figure 5 It is a flow chart of the latter part of the method for manufacturing the silicon oxide waveguide optical switch device of the present invention;

[0036] Figure 6 This is a diagram of the heat dissipation efficiency of the silicon oxide waveguide optical switch device of the present invention at different liquid flow rates. DETAILED DESCRIPTION

[0037] The present invention discloses a silicon oxide waveguide optical switch device. The silicon oxide waveguide optical switch device of the present invention is further described in detail below in conjunction with the embodiments of the accompanying drawings.

[0038] Embodiment 1: Figures 1 to 3 As shown, a silicon oxide waveguide optical switch device comprises a waveguide core layer, an upper cladding layer 1, a lower cladding layer 2 and a heating electrode for realizing an optical switch function. The waveguide core layer is arranged on the upper surface of the lower cladding layer 2, and the heating electrode is arranged on the upper surface of the upper cladding layer 1, and is used to heat the waveguide core layer to change its refractive index to realize optical path switching. The materials of the upper cladding layer 1 and the lower cladding layer 2 are both silicon oxide, and the material of the waveguide core layer is doped silicon oxide with a higher refractive index than silicon oxide. A cover plate 5 is arranged on the upper cladding layer 1 and the heating electrode to completely cover the two, and a cover plate 5 extending downward to the inside of the lower cladding layer 2 is arranged from the upper end surface of the cover plate 5. The heat dissipation flow channel structure is located on the front side of the waveguide core layer. The heat dissipation flow channel structure includes a fluid inlet 3, a fluid outlet 4 and a fluid channel. The fluid inlet 3 and the fluid outlet 4 are both cylindrical cavities starting from the upper surface of the cover plate 5 and extending downward to the inside of the cover plate 5. The axis of the cylindrical cavity is along the up and down direction. The fluid inlet 3 and the fluid outlet 4 are arranged at intervals on the left and right. The fluid channel extends from the inside of the cover plate 5 to the inside of the lower cladding 2, and its two ends are respectively located below the fluid inlet 3 and the fluid outlet 4, and are connected to the fluid inlet 3 and the fluid outlet 4 in a one-to-one correspondence.

[0039] In this embodiment, when the silicon oxide waveguide optical switch is working, the cooling liquid flows into the fluid inlet 3 through the pipeline, then flows through the fluid channel, and finally flows out through the fluid outlet 4. During the flow of the liquid in the fluid channel, the liquid exchanges heat with the side wall of the fluid channel, which will take away the internal heat of the silicon oxide waveguide optical switch device, thereby achieving cooling and heat dissipation of the silicon oxide waveguide optical switch device and improving its switching speed.

[0040] Embodiment 2: This embodiment is basically the same as Embodiment 1, except that: in this embodiment, the fluid channel includes a first flow channel 6, a second flow channel 7 and a third flow channel 8. The first flow channel 6, the second flow channel 7 and the third flow channel 8 are all square cavities extending downward from the inside of the cover plate 5 to the inside of the lower cladding 2. The first flow channel 6 is located below the fluid inlet 3, and is connected to the fluid inlet 3 up and down. The third flow channel 8 is located below the fluid outlet 4, and is connected to the fluid outlet 4 up and down. The second flow channel 7 is located between the first flow channel 6 and the third flow channel 8, and is connected to the first flow channel 6 and the third flow channel 8 respectively.

[0041] In this embodiment, when the liquid flows into the fluid inlet 3 through the pipeline, the liquid flows through the first flow channel 6, the second flow channel 7 and the third flow channel 8 in sequence, and finally flows out through the fluid outflow outlet 4. During the flow of the liquid in the first flow channel 6, the second flow channel 7 and the third flow channel 8, heat exchange is performed with the side walls of the first flow channel 6, the second flow channel 7 and the third flow channel 8, which will take away the internal heat of the silicon oxide waveguide optical switch device, thereby achieving cooling and heat dissipation of the silicon oxide waveguide optical switch device.

[0042] In this embodiment, the first flow channel 6, the second flow channel 7 and the third flow channel 8 can be integrally formed by an etching process, and the process requirements are relatively low.

[0043] Embodiment 3: This embodiment is basically the same as Embodiment 2, except that: in this embodiment, the material of the cover plate 5 is a polydimethylsiloxane (PDMS) mixture, and the PDMS mixture is formed by uniformly mixing PDMS and a curing agent in a weight ratio of 10:1; the doped silicon oxide is germanium-doped silicon oxide or nitrogen-doped silicon oxide.

[0044] Embodiment 4: This embodiment is basically the same as Embodiment 2, except that: in this embodiment, the waveguide core layer is implemented using a Mach-Zehnder interferometer structure.

[0045] In this embodiment, the waveguide core layer includes two input waveguides, two 3dB couplers, two phase-shift arm waveguides and two output waveguides. Each 3dB coupler has two input ends and two output ends. The two input ends are respectively referred to as the first input end and the second input end, and the two output ends are respectively referred to as the first output end and the second output end. The first input end of each 3dB coupler is directly connected to the first output end, and the second input end is directly connected to the second output end. The two input waveguides are respectively referred to as the first input waveguide 9 and the second input waveguide 10. The two 3dB couplers are respectively referred to as the first coupler 11 and the second coupler 12. The two phase-shift arm waveguides are respectively referred to as the first phase-shift arm waveguide 13 and the second phase-shift arm waveguide 14. The two output waveguides are respectively referred to as the first output waveguide 15 and the second output waveguide 16. One end of the first input waveguide 9 and the second One end of the input waveguide 10 is used to access an external optical signal, the other end of the first input waveguide 9 is connected to the first input end of the first coupler 11, the other end of the second input waveguide 10 is connected to the second input end of the first coupler 11, the first output end of the first coupler 11 is connected to one end of the first phase-shift arm waveguide 13, the second output end of the first coupler 11 is connected to one end of the second phase-shift arm waveguide 14, the other end of the first phase-shift arm waveguide 13 is connected to the first input end of the second coupler 12, the other end of the second phase-shift arm waveguide 14 is connected to the second input end of the second coupler 12, the first output end of the second coupler 12 is connected to one end of the first output waveguide 15, the second output end of the second coupler 12 is connected to one end of the second output waveguide 16, and the other end of the first output waveguide 15 and the other end of the second output waveguide 16 are both used to output optical signals.

[0046] In this embodiment, a heat-insulating groove 17 is provided between the first phase-shifting arm waveguide 13 and the second phase-shifting arm waveguide 14 to prevent heat diffusion and improve thermal tuning efficiency. The heat-insulating groove 17 is a square cavity extending downward from the upper end surface of the upper cladding 1 to the inside of the lower cladding 2.

[0047] In this embodiment, the heating electrode includes a heating resistor wire 18 and two metal electrodes 19. The heating resistor wire 18 is located directly above the first phase-shift arm waveguide 13. The two metal electrodes 19 are respectively connected to the two ends of the heating resistor wire 18 for connecting to an external power source to supply power to the heating resistor wire 18.

[0048] In this embodiment, the materials of the two metal electrodes 19 are both Al or Au.

[0049] In this embodiment, the first coupler 11 can evenly distribute the optical signal input by the first input waveguide 9 or the second input waveguide 10 into the first phase-shift arm waveguide 13 and the second phase-shift arm waveguide 14, and the second coupler 12 can evenly distribute the optical signal output by the first phase-shift arm waveguide 13 or the second phase-shift arm waveguide 14 into the first output waveguide 15 and the second output waveguide 16. By energizing the two metal electrodes 19, the heating resistor 18 heats the first phase-shift arm waveguide 13, and changes the phase of the first phase-shift arm waveguide 13, thereby changing the transmission path of light in the optical switch and realizing optical path switching. When the heating resistor wire 18 heats the first phase-shift arm waveguide 13, the phase of the first phase-shift arm waveguide 13 is in the interference state of the double optical paths in the first output waveguide 15, and the transmission of the optical path from the first input waveguide 9 to the first output waveguide 15 or the transmission of the second input waveguide 10 to the second output waveguide 16 is realized, that is, the cross state; when the heating resistor wire 18 heats the first phase-shift arm waveguide 13, the phase of the first phase-shift arm waveguide 13 is in the interference state of the double optical paths in the second output waveguide 16, and the transmission of the optical path from the first input waveguide 9 to the second output waveguide 16 or the transmission of the second input waveguide 10 to the first output waveguide 15 is realized, that is, the bar state.

[0050] The present invention also discloses a method for manufacturing the above-mentioned silicon oxide waveguide optical switch device. The method for manufacturing the silicon oxide waveguide optical switch device of the present invention is further described in detail below in conjunction with the accompanying drawings.

[0051] Example: Figure 4 and 5 As shown, a method for manufacturing a silicon oxide waveguide optical switch device comprises the following steps:

[0052] Step 1, selecting a silicon wafer or a quartz wafer with a silicon oxide material layer having a thickness of more than 10 μm grown on the surface, and the silicon oxide material layer is used as the lower cladding layer 2;

[0053] Step 2, growing doped silicon oxide on the upper surface of the lower cladding layer 2 to form a doped silicon oxide layer, and performing annealing treatment to eliminate stress;

[0054] Step 3, forming a mask of a waveguide core layer on the doped silicon oxide layer by photolithography, and etching the doped silicon oxide layer by an inductively coupled plasma etching process to form a waveguide core layer;

[0055] Step 4, chemically vapor depositing silicon oxide on the lower cladding layer 2 and the waveguide core layer to form an upper cladding layer 1;

[0056] Step 5, setting a heating electrode on the upper cladding layer 1;

[0057] Step 6, spin-coating photoresist on the upper cladding 1 and the heating electrode, photolithography the photoresist to form a partial structure of the fluid channel located in the upper cladding 1 and the lower cladding 2 and a mask of the heat-insulating groove 17 for preventing heat diffusion of the waveguide core layer and improving the thermal tuning efficiency, and completing the etching of the upper cladding 1 and the lower cladding 2 by an inductively coupled plasma etching process to form a partial structure of the fluid channel located in the upper cladding 1 and the lower cladding 2 and the heat-insulating groove 17; the structure obtained at this time is called the first partial structure;

[0058] Step 7, making a mask pattern of a part of the structure where the fluid channel is located on the cover plate 5, spin-coating photoresist on the base plate, transferring the mask pattern to the photoresist by ultraviolet exposure, and forming a positive mold of a part of the structure where the fluid channel is located on the cover plate 5 after development;

[0059] Step 8, PDMS and curing agent are mixed and stirred evenly in a weight ratio of 10:1, and bubbles are removed in a vacuum to obtain a PDMS mixture;

[0060] Step 9: Wrap the outer edge of the male mold with tin foil, pour the PDMS mixture onto the surface of the male mold, and bake on a heating table to solidify the PDMS mixture;

[0061] Step 10, peeling the solidified PDMS mixture from the positive mold, at which time the solidified PDMS mixture forms a cover plate 5, and the portion where the positive mold is peeled off forms a portion of the structure where the fluid channel is located on the cover plate 5;

[0062] Step 11: punch holes on the cover plate 5 using a puncher to form a fluid inlet 3 and a fluid outlet 4 connected to the fluid channel. The structure obtained at this time is called the second part structure;

[0063] Step 12: align and bond the second partial structure to the first partial structure to obtain a silicon oxide waveguide optical switch device.

[0064] In this embodiment, the photoresist in step 7 is SU8 photoresist, and the thickness of the photoresist is 40 μm.

[0065] In order to verify the performance of the silicon oxide waveguide optical switch device and the manufacturing method thereof of the present invention, the silicon oxide waveguide optical switch device of the present invention is simulated. During the simulation, the lower cladding 2 is made of quartz material with poor heat dissipation, wherein the width of the second flow channel 7 along the front-to-back direction is 100 μm, the depth of a portion of the first flow channel 6, the second flow channel 7 and the third flow channel 8 in the upper cladding 1 and the lower cladding 2 along the up-down direction is 40 μm, and the depth of a portion of the first flow channel 6, the second flow channel 7 and the third flow channel 8 in the cover plate 5 along the up-down direction is 40 μm, the width and height of each waveguide in the waveguide core layer are 3.4 μm, the heating electrode is located 10 μm above the waveguide core layer, the horizontal spacing between the second flow channel 7 and the waveguide core layer is 5 μm, the thermal conductivity of the silicon oxide material is set to 1.4 [W / (m*K)], and the state of the heating electrode temperature stepping from 400K to 290K is simulated, and the following is obtained: Figure 6 The heat dissipation efficiency diagram of the silicon oxide waveguide optical switch device of the present invention under different liquid flow rates is shown. Figure 6 In the equation, Q represents the cooling liquid flow rate. Figure 6 It can be seen that as the liquid flow rate in the heat dissipation channel structure increases, the temperature drop time of the silicon oxide waveguide optical switch device is significantly reduced and can be reduced to the sub-micron level, which is much higher than the heat dissipation efficiency of a simple quartz-based waveguide.

[0066] In summary, the silicon oxide waveguide optical switch device of the present invention allows the cooling liquid to circulate and dissipate heat by setting a heat dissipation channel structure, performs heat exchange through liquid flow, realizes cooling and heat dissipation, has high heat dissipation efficiency, fast switching speed, and has broad application prospects in optical interconnection, optical switching and other scenarios.

Claims

1. A silicon oxide waveguide optical switch device, comprising a waveguide core layer, an upper cladding layer, a lower cladding layer and a heating electrode for realizing an optical switch function, wherein the waveguide core layer is arranged on the upper surface of the lower cladding layer, and the heating electrode is arranged on the upper surface of the upper cladding layer, and is used to heat the waveguide core layer to change its refractive index to realize optical path switching, the materials of the upper cladding layer and the lower cladding layer are both silicon oxide, and the material of the waveguide core layer is doped silicon oxide having a higher refractive index than silicon oxide, characterized in that The upper cladding and the heating electrode are provided with a cover plate which completely covers both of them, a heat dissipation channel structure is provided from the upper end surface of the cover plate and extends downward to the interior of the lower cladding, the heat dissipation channel structure is located on the front side of the waveguide core layer, the heat dissipation channel structure comprises a fluid inlet, a fluid outlet and a fluid channel, the fluid inlet and the fluid outlet are both cylindrical cavities which start from the upper surface of the cover plate and extend downward to the interior of the cover plate, the axis of the cylindrical cavity is along the up and down direction, the fluid inlet and the fluid outlet are arranged at intervals on the left and right, the fluid channel extends from the interior of the cover plate to the interior of the lower cladding, and its two ends are respectively located below the fluid inlet and the fluid outlet, and are connected with the fluid inlet and the fluid outlet in a one-to-one correspondence.

2. A silicon oxide waveguide optical switch device according to claim 1, characterized in that The fluid channel includes a first flow channel, a second flow channel and a third flow channel. The first flow channel, the second flow channel and the third flow channel are all square cavities extending downward from the inside of the cover plate to the inside of the lower cladding. The first flow channel is located below the fluid inlet and is connected to the fluid inlet in an upper and lower manner. The third flow channel is located below the fluid outlet and is connected to the fluid outlet in an upper and lower manner. The second flow channel is located between the first flow channel and the third flow channel and is connected to the first flow channel and the third flow channel respectively. When liquid flows into the fluid inlet through a pipeline, the liquid flows through the first flow channel, the second flow channel and the third flow channel in sequence, and finally flows out through the fluid outlet. During the flow of the liquid in the first flow channel, the second flow channel and the third flow channel, the internal heat of the silicon oxide waveguide optical switch device will be taken away, thereby realizing the cooling and heat dissipation of the silicon oxide waveguide optical switch device.

3. The silicon oxide waveguide optical switch device according to claim 1, characterized in that The material of the cover plate is a polydimethylsiloxane (PDMS) mixture, and the PDMS mixture is formed by uniformly mixing PDMS and a curing agent in a weight ratio of 10:1; the doped silicon oxide is germanium-doped silicon oxide or nitrogen-doped silicon oxide.

4. The silicon oxide waveguide optical switch device according to claim 2, characterized in that The waveguide core layer is realized by using a Mach-Zehnder interferometer structure.

5. The silicon oxide waveguide optical switch device according to claim 2, characterized in that The waveguide core layer includes two input waveguides, two 3dB couplers, two phase-shift arm waveguides and two output waveguides. Each 3dB coupler has two input ends and two output ends. The two input ends are respectively referred to as the first input end and the second input end, and the two output ends are respectively referred to as the first output end and the second output end. The first input end of each 3dB coupler is directly connected to the first output end, and the second input end is directly connected to the second output end. The two input waveguides are respectively referred to as the first input waveguide and the second input waveguide, the two 3dB couplers are respectively referred to as the first coupler and the second coupler, the two phase-shift arm waveguides are respectively referred to as the first phase-shift arm waveguide and the second phase-shift arm waveguide, and the two output waveguides are respectively referred to as the first output waveguide and the second output waveguide, and one end of the first input waveguide and one end of the second input waveguide are both used to access external light. The first input waveguide is connected to the first input end of the first coupler, the other end of the second input waveguide is connected to the second input end of the first coupler, the first output end of the first coupler is connected to one end of the first phase-shift arm waveguide, the second output end of the first coupler is connected to one end of the second phase-shift arm waveguide, the other end of the first phase-shift arm waveguide is connected to the first input end of the second coupler, the other end of the second phase-shift arm waveguide is connected to the second input end of the second coupler, the first output end of the second coupler is connected to one end of the first output waveguide, the second output end of the second coupler is connected to one end of the second output waveguide, and the other end of the first output waveguide and the other end of the second output waveguide are both used to output optical signals.

6. The silicon oxide waveguide optical switch device according to claim 5, characterized in that An insulation groove is provided between the first phase-shift arm waveguide and the second phase-shift arm waveguide to prevent heat diffusion and improve thermal tuning efficiency. The insulation groove is a square cavity extending downward from the upper end surface of the upper cladding to the interior of the lower cladding.

7. The silicon oxide waveguide optical switch device according to claim 5, characterized in that The heating electrode comprises a heating resistor wire and two metal electrodes. The heating resistor wire is located directly above the first phase-shift arm waveguide. The two metal electrodes are respectively connected to both ends of the heating resistor wire and are used to connect to an external power source to supply power to the heating resistor wire.

8. The silicon oxide waveguide optical switch device according to claim 7, characterized in that The materials of the two metal electrodes are Al or Au.

9. A method for manufacturing a silicon oxide waveguide optical switch device according to any one of claims 1 to 8, characterized in that The following steps are involved: Step 1, selecting a silicon wafer or a quartz wafer with a silicon oxide material layer having a thickness of more than 10 μm grown on the surface, and the silicon oxide material layer is used as a lower cladding layer; Step 2, growing doped silicon oxide on the upper surface of the lower cladding layer to form a doped silicon oxide layer, and performing annealing treatment to eliminate stress; Step 3, forming a mask of a waveguide core layer on the doped silicon oxide layer by photolithography, and etching the doped silicon oxide layer by an inductively coupled plasma etching process to form a waveguide core layer; Step 4, chemically vapor depositing silicon oxide on the lower cladding layer and the waveguide core layer to form an upper cladding layer; Step 5, setting a heating electrode on the upper cladding; Step 6, spin-coating photoresist on the upper cladding and the heating electrode, photolithography the photoresist to form a mask of a part of the structure where the fluid channel is located in the upper cladding and the lower cladding, and a heat-insulating groove for preventing heat diffusion of the waveguide core layer and improving the thermal tuning efficiency, and completing the etching of the upper cladding and the lower cladding by an inductively coupled plasma etching process to form a part of the structure where the fluid channel is located in the upper cladding and the lower cladding, and the heat-insulating groove; The structure obtained at this time is called the first part structure; Step 7, making a mask pattern of a part of the structure where the fluid channel is located on the cover plate, spin-coating photoresist on the base plate, transferring the mask pattern to the photoresist by ultraviolet exposure, and forming a positive mold of a part of the structure where the fluid channel is located on the cover plate after development; Step 8, PDMS and curing agent are mixed and stirred evenly in a weight ratio of 10:1, and bubbles are removed in a vacuum to obtain a PDMS mixture; Step 9: Wrap the outer edge of the male mold with tin foil, pour the PDMS mixture onto the surface of the male mold, and bake on a heating table to solidify the PDMS mixture; Step 10, peeling off the solidified PDMS mixture from the positive mold, at which time the solidified PDMS mixture forms a cover plate, and the portion where the positive mold is peeled off forms a part of the structure where the fluid channel is located on the cover plate; Step 11: Use a puncher to punch holes on the cover plate to form a fluid inlet and a fluid outlet connected to the fluid channel. The structure obtained at this time is called the second part structure; Step 12: align and bond the second partial structure to the first partial structure to obtain a silicon oxide waveguide optical switch device.

10. The method for manufacturing a silicon oxide waveguide optical switch device according to claim 9, characterized in that The photoresist in step 7 is SU8 photoresist, and the thickness of the photoresist is 40 μm.

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