A continuous on-chip non-volatile adjustment structure based on MEMS

Abstract

The application discloses a kind of on-chip continuous non-volatile adjustment structures based on MEMS.It includes substrate, regulator and brake;The regulator includes transmission rod, fixed island spring structure and one-way electrostatic comb driver;Transmission rod is cross-shaped structure, brake includes brake rod, two pairs of fixed island spring structure, a set of bidirectional electrostatic comb driver and mechanical stop structure, brake rod is long strip structure, and the brake end of brake rod is used to contact connection with the brake end of transmission rod to brake transmission rod through van der waals force.The application realizes the function of wide-range continuous non-volatile adjustment, can reduce the power consumption of network, has the advantages of low power consumption, wide adjustment range, simple manufacturing process, strong flexibility and no additional loss, etc.

Description

Technical Field

[0001] This invention relates to a non-volatile adjustment optical structure in the field of integrated optoelectronic devices, specifically a structure that uses an electrostatic comb to drive an adjuster and a brake, and utilizes van der Waals forces to achieve continuous non-volatile adjustment. Background Technology

[0002] With the rapid development of large-scale data networks, reconfigurable and programmable data networks based on silicon-based photonics platforms are becoming increasingly mature. However, due to the explosive growth in data volume, the energy consumption of data center networks is increasing, and the accompanying heat treatment issues are increasing the cost of data centers. How to further reduce the energy consumption of networks is an urgent problem to be solved.

[0003] Non-volatile modulation, a modulation method that can reversibly switch between different network states without requiring additional energy to maintain a state, can significantly reduce network power consumption. Microelectromechanical systems (MEMS)-based integrated photonic devices utilize capacitive operating principles, generating minimal current during operation, thus also significantly reducing system power consumption compared to current integrated photonic devices. These two technologies enable ultra-low power network reconfiguration, further enhancing the potential of integrated optical networks.

[0004] The proposed methods for achieving non-volatile regulation can be divided into two types:

[0005] One approach is based on special materials that can undergo reversible changes in refractive index under specific conditions. These materials do not require additional energy to maintain the altered state and can be restored to their initial state under further conditions. Non-volatile spectroscopic modulation and non-volatile optical switches have been achieved using this method. However, non-volatile modulation based on special materials generally involves significant optical losses, and the energy consumption during material reconstruction is not reduced. Furthermore, achieving continuous modulation by adjusting different material lengths to achieve varying degrees of modulation is difficult. Therefore, non-volatile modulation methods based on special materials still have many limitations.

[0006] Another approach is based on MEMS, which utilizes the non-volatility of mechanical structures to achieve optical non-volatility through special mechanical structure design. Compared with methods based on special materials, this approach has the advantages of ultra-low power consumption during the reconstruction process, low optical loss, and no need to introduce additional materials. However, currently realized MEMS non-volatile adjustment is generally bistable adjustment, and multistable or continuous non-volatile adjustment still needs further research. Summary of the Invention

[0007] In view of the above-mentioned background technology, the purpose of this invention is to provide an on-chip MEMS device that achieves continuous non-volatile adjustment by using van der Waals forces to drive an regulator and a brake via an electrostatic comb. Under the action of an external voltage, this device uses an electrostatic comb driver to drive the regulator to move. After the regulator moves to the target position, the electrostatic comb driver then drives the brake, causing the brake to contact the regulator and adhere under the action of van der Waals forces. At this point, after removing all external voltages from the device, the regulator can still balance at the new position under the action of the brake, thereby achieving continuous and non-volatile adjustment.

[0008] The technical solution adopted in this invention is:

[0009] It mainly includes a base and an adjuster and a brake placed on the base; the adjuster includes a transmission rod, two pairs of fixed island spring structures and a set of unidirectional electrostatic comb drivers; the transmission rod has a cross-shaped structure, one end of the long side of the cross-shaped structure is the connecting end, which is connected to the continuous non-volatile adjustment structure, and the other end of the long side is connected to the unidirectional electrostatic comb driver; one end of the short side of the cross-shaped structure is suspended without connection, and the other end of the short side is the braking end, which is used to contact and connect with the brake rod of the brake; two pairs of fixed island spring structures are distributed on both sides of the short side of the cross-shaped structure, and each pair of fixed island spring structures is symmetrically distributed on both sides of the long side.

[0010] The unidirectional electrostatic comb driver includes a fixed electrostatic comb and a unidirectional movable electrostatic comb. The fixed electrostatic comb is kept stationary and a voltage is applied to it. The unidirectional movable electrostatic comb is fixedly connected to the other end of the long side of the transmission rod. The unidirectional movable electrostatic comb and the transmission rod are suspended structures. The unidirectional movable electrostatic comb and the transmission rod are moved as a whole by a continuous non-volatile adjustment structure, thereby causing the unidirectional movable electrostatic comb to move closer to or away from the fixed electrostatic comb.

[0011] Both the fixed electrostatic comb and the unidirectional movable electrostatic comb mainly consist of a comb handle and comb teeth periodically distributed on the comb handle. The comb handle and the other end of the long side of the transmission rod are fixedly connected. The length direction of the comb handle is parallel to the short side of the transmission rod. Each comb tooth is arranged on the side of the comb handle away from the transmission rod and is arranged periodically along the length direction of the comb handle. The length direction of each comb tooth is parallel to the long side of the transmission rod. One end of the comb tooth is connected to the comb handle, and the other end is not connected.

[0012] Each pair of fixed island spring structures is mainly composed of two fixed island spring assemblies symmetrically distributed on both sides of the long side of the transmission rod. Each fixed island spring assembly mainly consists of a folded spring and a fixed island that supports the folded spring. The fixed island remains fixed, and part of the folded spring is fixedly connected to the fixed island, while the other part is fixedly connected to the long side of the transmission rod.

[0013] The brake includes a brake lever, two pairs of fixed island spring structures, a set of bidirectional electrostatic comb actuators, and a mechanical stop structure. The brake lever is a long strip structure, with its length parallel to the short side of the transmission rod in the regulator and located on the same straight line. One end of the brake lever is the braking end, which is used to contact and connect with the braking end of the transmission rod in the regulator to brake the transmission rod through van der Waals force. The other end of the brake lever is the limiting end, which is arranged close to the mechanical stop structure. The brake lever is connected in sequence from the braking end to the limiting end to the first set of fixed island spring structures, the bidirectional electrostatic comb actuator, and the second set of fixed island spring structures.

[0014] In the brake, two pairs of fixed island spring structures are distributed on both sides of the bidirectional electrostatic comb driver. The fixed island spring structure of the bidirectional electrostatic comb driver is the same as the fixed island spring structure in the regulator.

[0015] The bidirectional electrostatic comb driver comprises a pair of bidirectional electrostatic comb assemblies symmetrically distributed on both sides of the brake lever's length direction. Each bidirectional electrostatic comb assembly includes two fixed electrostatic combs and one bidirectional movable electrostatic comb. Voltage is applied to the two fixed electrostatic combs, which have the same structure as the fixed electrostatic combs in the regulator. The bidirectional movable electrostatic comb has a similar structure to the unidirectional movable electrostatic comb in the regulator, but differs in that it has symmetrical comb teeth distributed on both sides of the comb handle's length direction. The two fixed electrostatic combs are respectively arranged on both sides of the bidirectional movable electrostatic comb. The end of the bidirectional movable electrostatic comb near the brake lever is connected to the brake lever, while the end away from the brake lever is not connected. The end of each fixed electrostatic comb near the brake lever is not connected, while the end away from the brake lever is connected to an external circuit. One fixed electrostatic comb near the brake lever's braking end is the braking fixed electrostatic comb, and the other fixed electrostatic comb near the brake lever's limiting end is the releasing fixed electrostatic comb.

[0016] The mechanical stopping structure is a conical structure whose bottom is supported and connected to the base through a buried layer, and the tip of the conical structure is arranged opposite to the limiting end of the brake rod.

[0017] The regulator and brake are arranged on the substrate, wherein the fixed electrostatic comb of the unidirectional electrostatic comb driver, the fixed island of the fixed island spring structure, and the fixed electrostatic comb of the bidirectional electrostatic comb driver are all arranged on the substrate with their bottoms supported by the buried layer.

[0018] The beneficial effects of this invention are:

[0019] This invention achieves a wide range of continuous non-volatile adjustment functions, and the structure itself adopts a capacitive drive structure, which can significantly reduce the power consumption of the network. It also uses simple materials, has a simple structure, and low manufacturing cost.

[0020] This invention offers high flexibility and can be used to create various continuously non-volatile adjustable devices by changing the connection structure without introducing additional losses to the connection structure.

[0021] In summary, this invention utilizes van der Waals forces to achieve continuous non-volatile adjustment by driving the regulator and brake with an electrostatic comb. It has significant advantages such as low power consumption, large adjustment range, simple manufacturing process, high flexibility, and no introduction of additional losses. Attached Figure Description

[0022] Figure 1 This is a top view of the structure of the present invention in its initial state;

[0023] Figure 2 yes Figure 1 Cross-sectional view of line A-A';

[0024] Figure 3 yes Figure 1 Cross-sectional view of B-B';

[0025] Figure 4 yes Figure 1 Cross-sectional view of C-C';

[0026] Figure 5 This is a top view of the structure when the regulator is working, the regulator has reached the target position, and the brake is not working.

[0027] Figure 6 This is a top view of the structure when the brake is working and the regulator has completed braking to the target position;

[0028] Figure 7 This is a top view of the structure after the brake has been released from the regulator while the brake is in operation.

[0029] Figure 8 This is a schematic diagram of an embodiment of the present invention, showing how the regulator is connected to an adjustable coupler to achieve continuous non-volatile spectroscopic adjustment function;

[0030] Figure 9 yes Figure 8 Cross-sectional view of D-D';

[0031] Figure 10 This is the optical field transmission diagram of the directional coupler structure at 1550nm in its initial state;

[0032] Figure 11 This describes how the output optical power of the through output port and the cross output port at a wavelength of 1550nm varies with the distance between the fixed waveguide and the movable coupling waveguide.

[0033] In the diagram: 1. Drive rod, 2. Fixed island, 3. Folding spring, 4. Unidirectional movable electrostatic comb, 5. Fixed electrostatic comb, 6. Brake rod, 7. Braking fixed electrostatic comb, 8. Bidirectional movable electrostatic comb, 9. Releasing braking fixed electrostatic comb, 10. Mechanical stop structure, 11. Substrate, 12. Buried layer, 13. Fixed waveguide, 14. Movable coupling waveguide, 15. Connecting piece, 16. Input port, 17. Straight-through output port, 18. Cross output port. Detailed Implementation

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the scope of protection of the present invention.

[0035] like Figure 1 As shown, the present invention mainly includes a base 11 and an adjuster and a brake placed on the base 11.

[0036] like Figure 1 As shown, the regulator includes a transmission rod 1, two pairs of fixed island spring structures 2 and 3, and a set of unidirectional electrostatic comb actuators 4 and 5; Figure 1 As shown, the transmission rod 1 in the regulator has a cross-shaped structure. One end of the long side of the cross-shaped structure is the connection end, which is connected to the structure that needs to achieve continuous non-volatile adjustment. The other end of the long side is connected to the unidirectional movable electrostatic comb 4 of the unidirectional electrostatic comb driver 4, 5. One end of the short side of the cross-shaped structure is suspended without connection, and the other end of the short side is the braking end. The braking end is arranged close to the brake rod 6 and is used to contact and connect with the brake rod 6 of the brake. Two pairs of fixed island spring structures 2, 3 are distributed on both sides of the short side of the cross-shaped structure. Each pair of fixed island spring structures 2, 3 is symmetrically distributed on both sides of the long side.

[0037] like Figure 1 As shown, the unidirectional electrostatic comb driver 4 and 5 in the regulator includes a fixed electrostatic comb 5 and a unidirectional movable electrostatic comb 4; the fixed electrostatic comb 5 is kept fixed, and the other end of the long side of the unidirectional movable electrostatic comb 4 and the transmission rod 1 are fixedly connected. The unidirectional movable electrostatic comb 4 and the transmission rod 1 are suspended structures and connected to a continuous non-volatile adjustment structure. The continuous non-volatile adjustment structure drives the unidirectional movable electrostatic comb 4 and the transmission rod 1 to move as a whole, thereby driving the unidirectional movable electrostatic comb 4 to move closer to or away from the fixed electrostatic comb 5.

[0038] The fixed electrostatic comb 5 and the unidirectional movable electrostatic comb 4 have similar structures. They are mainly composed of a comb handle and comb teeth that are periodically distributed on the comb handle. The comb handle and the other end of the long side of the transmission rod 1 are fixedly connected. The length direction of the comb handle is parallel to the short side of the transmission rod 1. Each comb tooth is arranged on the side of the comb handle away from the transmission rod 1 and is arranged periodically along the length direction of the comb handle. The length direction of each comb tooth is parallel to the long side of the transmission rod 1. One end of the comb tooth is connected to the comb handle, and the other end is not connected.

[0039] like Figure 3 As shown, the fixed electrostatic comb 5 is supported by a buried layer material 12 below the comb handle, and the buried layer material 12 is connected to the base 11.

[0040] The fixed electrostatic comb 5 and the unidirectional movable electrostatic comb 4 are adjacent to each other. The comb teeth of the fixed electrostatic comb 5 and the unidirectional movable electrostatic comb 4 are arranged in an alternating pattern, so that when the fixed electrostatic comb 5 and the unidirectional movable electrostatic comb 4 are close to each other, the comb teeth of the fixed electrostatic comb 5 and the unidirectional movable electrostatic comb 4 are interwoven.

[0041] The fixed electrostatic comb 5 is connected to the external circuit.

[0042] The first set of fixed island spring structures 2 and 3 are connected between the connecting end and the short side of the long side of the transmission rod 1. The second set of fixed island spring structures 2 and 3 are connected between the short side of the long side of the transmission rod 1 and the unidirectional movable electrostatic comb 4.

[0043] like Figure 1 As shown, each pair of fixed island spring structures 2 and 3 is mainly composed of two fixed island spring assemblies symmetrically distributed on both sides of the long side of the transmission rod 1. Each fixed island spring assembly mainly consists of a folding spring 3 and a fixed island 2 that supports the folding spring 2. The fixed island 2 remains fixed, and part of the folding spring 3 is fixedly connected to the fixed island 2, while the other part is fixedly connected to the long side of the transmission rod 1.

[0044] The folding spring 3 comprises a spring handle, two short beams connected to both ends of the spring handle and perpendicular to the length direction of the spring handle, and two long beams connected to the middle of the spring handle and perpendicular to the length direction of the spring handle. The ends of the two short beams furthest from the spring handle are each connected to a fixed island 2, and the ends of the two long beams furthest from the spring handle are connected to the transmission rod 1. The length direction of the spring handle is parallel to the length direction of the long side of the transmission rod 1. The four beams—two long beams and two short beams—are distributed in parallel, and their length directions are perpendicular to the length direction of the long side of the transmission rod 1. Each folding spring 3 requires support from two fixed islands 2 located on the same side of the long side of the transmission rod 1. Therefore, each set of fixed island spring structures 2 and 3 contains four fixed islands 2, symmetrically distributed in pairs on both sides of the transmission rod 1.

[0045] like Figure 2 As shown, the fixed island 2 has a square structure, supported by a buried layer material 12 below, and is connected to the base 11 through the buried layer material 12. The folding spring 3 has a suspended structure.

[0046] The brake includes a brake lever 6, two pairs of fixed island spring structures 2 and 3, a set of bidirectional electrostatic comb actuators 7, 8, and 9, and a mechanical stop structure 10; as shown Figure 1As shown, the brake lever 6 is a long strip structure, with its length parallel to the short side of the transmission rod 1 in the regulator and located on the same straight line. One end of the brake lever 6 is the braking end, which is used to contact and connect with the braking end of the short side of the transmission rod 1 in the regulator to brake the transmission rod 1 through van der Waals force. The other end of the brake lever 6 is the limiting end, which is arranged close to the mechanical stop structure 10. The brake lever 6 is connected in sequence from the braking end to the limiting end to the first set of fixed island spring structures 2 and 3, bidirectional electrostatic comb drivers 7, 8 and 9, and the second set of fixed island spring structures 2 and 3.

[0047] In the brake, two pairs of fixed island spring structures 2 and 3 are distributed on both sides of the bidirectional electrostatic comb driver 7, 8, and 9. The fixed island spring structures 2 and 3 of the bidirectional electrostatic comb driver 7, 8, and 9 have the same structure as the fixed island spring structures 2 and 3 in the regulator.

[0048] In the brake, each pair of fixed island spring structures 2 and 3 is mainly composed of two fixed island spring assemblies symmetrically distributed on both sides of the brake lever 6. Each fixed island spring assembly is mainly composed of a folding spring 3 and a fixed island 2 that supports the folding spring 2. The fixed island 2 remains fixed, and part of the folding spring 3 is fixedly connected to the fixed island 2, while the other part is fixedly connected to the brake lever 6.

[0049] like Figure 1 As shown, the bidirectional electrostatic comb actuators 7, 8, and 9 consist of a pair of bidirectional electrostatic comb assemblies symmetrically distributed on both sides of the brake lever 6 along its length. Each bidirectional electrostatic comb assembly includes two fixed electrostatic combs 7 and 9 and one bidirectional movable electrostatic comb 8. The two fixed electrostatic combs 7 and 9 have the same structure as the fixed electrostatic comb 5 in the regulator. The bidirectional movable electrostatic comb 8 has a similar structure to the unidirectional movable electrostatic comb 4 in the regulator, but the difference is that the bidirectional movable electrostatic comb 8 has symmetrical comb teeth distributed on both sides of the comb handle along its length. The two fixed electrostatic combs 7 and 9 are respectively arranged on both sides of the bidirectional movable electrostatic comb 8. The end of the bidirectional movable electrostatic comb 8 near the brake lever 6 is connected to the brake lever 6, while the end away from the brake lever 6 is not connected. The end of each fixed electrostatic comb 7 and 9 near the brake lever 6 is not connected, while the end away from the brake lever 6 is connected to an external circuit. One fixed electrostatic comb 7 near the braking end of the brake lever 6 is a braking fixed electrostatic comb 7 used for braking, and the other fixed electrostatic comb 9 near the limiting end of the brake lever 6 is a braking release fixed electrostatic comb 9 used for releasing the brake.

[0050] Among them, the fixed electrostatic combs 7 and 9 and the bidirectional movable electrostatic comb 8 are adjacent to each other. The comb teeth of each fixed electrostatic comb 7 and 9 and the comb teeth of the bidirectional movable electrostatic comb 8 are arranged in opposite directions and staggered, so that when the bidirectional movable electrostatic comb 8 and the fixed electrostatic comb 7 / 9 on one side are close, the comb teeth of the fixed electrostatic comb 5 and the bidirectional movable electrostatic comb 8 are interwoven.

[0051] Two fixed electrostatic combs 7 and 9 are connected to the external circuit.

[0052] like Figure 1 and Figure 4 As shown, the mechanical stopping structure 10 is a conical structure whose bottom is supported and connected to the base 11 by the buried layer 12. The tip of the conical structure is arranged directly opposite the limiting end of the brake lever 6. When the limiting end of the brake lever 6 approaches the mechanical stopping structure 10, it will contact the tip of the mechanical stopping structure 10 to prevent mechanical damage caused by excessive further movement. The contact area between the limiting end of the brake lever 6 and the tip of the mechanical stopping structure 10 is small, so they will not stick together under the action of van der Waals forces.

[0053] In this invention, the unidirectional electrostatic comb drivers 4 and 5 and the bidirectional electrostatic comb drivers 7, 8, and 9 are collectively referred to as electrostatic comb drivers. The fixed electrostatic comb 5 in the unidirectional electrostatic comb drivers 4 and 5, and the braking fixed electrostatic comb 7 and the de-braking fixed electrostatic comb 9 in the bidirectional electrostatic comb drivers 7, 8, and 9 are collectively referred to as fixed electrostatic combs. The unidirectional movable electrostatic comb 4 in the unidirectional electrostatic comb drivers 4 and 5, and the bidirectional movable electrostatic comb 8 in the bidirectional electrostatic comb drivers 7, 8, and 9 are collectively referred to as movable electrostatic combs. The overall structure will be further described below:

[0054] like Figure 5 , Figure 6 , Figure 7 As shown, when the electrostatic comb actuators 4, 5, 7, 8, and 9 are in operation, they apply voltage to the fixed electrostatic combs 5, 7, and 9 through an external circuit, creating a potential difference between them and the movable electrostatic combs 4 and 8. This potential difference generates an attractive force between the fixed electrostatic combs 5, 7, and 9 and their corresponding movable electrostatic combs 4 and 8. Since the fixed electrostatic combs 5, 7, and 9 are connected to the substrate 11 through the buried layer material 12 and are immovable, while the movable electrostatic combs 4 and 8 are suspended and movable structures, the movable electrostatic combs 4 and 8 will move closer to the fixed electrostatic combs 5, 7, and 9. The movement of the movable electrostatic combs 4 and 8 can drive the transmission rod 1 or the brake rod 6 to move, and the movement of the transmission rod 1 or the brake rod 6 will in turn cause the folding spring 3 in the fixed island spring structure 2 and 3 connected to it to undergo a certain elastic deformation.

[0055] like Figure 5 , Figure 6 , Figure 7 As shown, the electrostatic comb drivers 4, 5, 7, 8, and 9 can control the displacement by adjusting the voltage applied by the external circuit during operation.

[0056] like Figure 5As shown, in the regulator, as the externally applied voltage increases, the unidirectional movable electrostatic comb 4 will drive the transmission rod 1 to move closer to the fixed electrostatic comb 5 along the long side under the attraction between it and the fixed electrostatic comb 5, thereby realizing the continuous adjustment of the structure connected to the transmission rod 1.

[0057] like Figure 6 As shown, when the regulator is adjusted to the target position, the brake is adjusted. Under the action of the brake-fixed electrostatic comb 7, the bidirectional movable electrostatic comb 8 drives the brake rod 6 to approach the brake end of the transmission rod 1 in the regulator along its length direction. When the brake end of the brake rod 6 contacts the brake end of the transmission rod 1 in the regulator, the two are tightly attracted together under the action of van der Waals force, completing the braking of the regulator. At this time, after removing the driving voltage of the brake and the driver, the entire structure can still be stabilized in a balanced state, thereby realizing non-volatile regulation.

[0058] like Figure 7 As shown, if the target position of the regulator is to be reconstructed, a voltage is applied to the release-braking electrostatic comb 9. At this time, the bidirectional movable electrostatic comb 8, under the action of the release-braking electrostatic comb 9, applies a pulling force to the brake rod 6 in a direction away from the regulator. This pulling force counteracts the van der Waals force, and the pulling force gradually increases with the increase of the applied voltage. When the pulling force reaches a certain level, the tight connection between the brake rod 6 and the transmission rod 1 in the regulator is broken, and the two separate. The regulator loses its braking force, and the transmission rod 1 of the regulator returns to its initial position under the elastic force of the two sets of folding springs 3. Under the attraction of the release-braking electrostatic comb 9, the bidirectional movable electrostatic comb 8 of the brake drives the brake rod 6 to move along its length towards the mechanical stop structure 10 until the limiting end of the brake rod 6 contacts the tip of the mechanical stop structure 10. At this time, because the contact area between the mechanical stop structure 10 and the stable end of the brake rod 6 is small, the two will not be tightly bound by intermolecular van der Waals forces. When the driving voltage applied to the release-braking electrostatic comb 9 is removed, the brake rod 6 can return to its initial position under the elastic force of the two sets of folding springs 3. Figure 1 The initial position is shown. This completes a full non-volatile adjustment process.

[0059] The transmission rod 1, folding spring 3, and unidirectional movable electrostatic comb 4 in the regulator, and the brake rod 6 and bidirectional movable electrostatic comb 8 in the brake, are suspended and movable. The remaining structures are fixed to the base 11 by the buried layer material 12. All structures in the regulator and brake (excluding the buried layer material 12 and the base 11) are made of the same material and have the same thickness, and the entire structure can be manufactured using monolithic integrated processing.

[0060] The following describes one embodiment of the present invention:

[0061] like Figure 8As shown, this embodiment utilizes the above-described structure to achieve continuous non-volatile adjustment of the splitting ratio of a directional coupler 13 and 14. The directional coupler consists of a fixed waveguide 13 and a movable waveguide 14 connected together. The two waveguides are parallel and their length directions are perpendicular to the length direction of the long side of the transmission rod 1 in the regulator. The movable waveguide 14 is connected to the connecting end of the transmission rod 1 via a connecting piece 15. The connecting piece 15 is relatively thin to ensure that the optical field can be well confined within the movable waveguide 14, such as... Figure 9 As shown. The movable waveguide 14 can move closer to or further away from the fixed waveguide 13 under the action of the transmission rod 1. The fixed waveguide 13 and the movable waveguide 14 are symmetrical in structure, each consisting of a straight waveguide and curved waveguides connected to both sides of the straight waveguide. Taking one end of the fixed waveguide 13 as the input terminal 16, the other end of the fixed waveguide 13 is the straight-through output terminal 17, and the output terminal of the movable waveguide 14 near the straight-through output terminal 17 is the cross-output terminal 18.

[0062] Silicon-on-insulator (SOI) was chosen as the implementation platform, with a 220 nm thick silicon top layer, a 2 μm thick silicon dioxide buried layer, and a silicon substrate. The considered wavelength range was 1530 nm to 1570 nm, using TE-polarized optical signals. The coupling waveguide width was 400 nm, and the coupling waveguide length was 25 μm. The curved waveguide consisted of two 90° circular arcs with a radius of 3 μm joined together. The initial distance between the fixed waveguide and the movable waveguide was 200 nm.

[0063] The optical performance of the device was simulated and verified using the three-dimensional finite-difference time-domain (3D-FDTD) method. In the initial state, almost all the light field incident from input port 16 was coupled into the movable waveguide 14 and output from the cross-output port 18. Figure 10 As shown. When a voltage is applied to the regulator, the movable waveguide 14 will move under the drive of the transmission rod 1. By adjusting the applied voltage, the distance between the movable waveguide 14 and the fixed waveguide 13 can be precisely and continuously controlled. Different distances correspond to different splitting ratios of the through output port 17 and the cross output port 18, thereby achieving continuous adjustment of the splitting ratio. Figure 11The optical power at the two output ports is shown as a function of the distance between the two waveguides. It can be seen that when the distance between the two waveguides is initially 200 nm, almost all the optical power is output from the cross-output port 18. When the distance between the two waveguides is adjusted to 650 nm, the optical power can be adjusted entirely to the output of the through port 17. The splitting ratio between the two output ports can be continuously adjusted from 0 to 1 with very low loss. When the target splitting ratio is reached, the brake can be driven to brake the regulator, achieving a non-volatile adjustment effect. The directional coupler structure in this embodiment has a relatively small bandwidth; however, the directional coupler structure can be replaced with some optical adjustment structures with larger bandwidths to achieve continuous non-volatile adjustment over a large bandwidth range. Therefore, this invention has significant advantages such as low power consumption, large adjustment range, simple manufacturing process, high flexibility, and no introduction of additional losses.

[0064] The above embodiments are used to explain and illustrate the present invention, but not to limit the present invention. Any modifications and changes made to the present invention within the spirit and scope of the claims shall fall within the protection scope of the present invention.

Claims

1. An on-chip continuous non-volatile adjustment structure based on MEMS, characterized in that: It mainly includes a base (11) and an adjuster and a brake placed on the base (11); the adjuster includes a transmission rod (1), two pairs of fixed island spring structures (2, 3) and a set of unidirectional electrostatic comb drivers (4, 5); the transmission rod (1) is a cross-shaped structure, one end of the long side of the cross-shaped structure is the connecting end, the connecting end is connected to the continuous non-volatile adjustment structure, and the other end of the long side is connected to the unidirectional electrostatic comb driver (4, 5); one end of the short side of the cross-shaped structure is suspended without connection, and the other end of the short side is the braking end, which is used to contact and connect with the brake rod (6) of the brake; two pairs of fixed island spring structures (2, 3) are distributed on both sides of the short side of the cross-shaped structure, and each pair of fixed island spring structures (2, 3) is symmetrically distributed on both sides of the long side; The brake includes a brake lever (6), two pairs of fixed island spring structures (2, 3), a set of bidirectional electrostatic comb drivers (7, 8, 9), and a mechanical stop structure (10). The brake lever (6) is a long strip structure, and its length direction is parallel to the short side of the transmission rod (1) in the regulator and located on the same straight line. One end of the brake lever (6) is the braking end, which is used to contact and connect with the braking end of the transmission rod (1) in the regulator to brake the transmission rod (1) through van der Waals force. The other end of the brake lever (6) is the limiting end, which is arranged close to the mechanical stop structure (10). The brake lever (6) is connected in sequence from the braking end to the limiting end to the first set of fixed island spring structures (2, 3), the bidirectional electrostatic comb drivers (7, 8, 9), and the second set of fixed island spring structures (2, 3).

2. The on-chip continuous non-volatile adjustment structure based on MEMS according to claim 1, characterized in that: The unidirectional electrostatic comb driver (4, 5) includes a fixed electrostatic comb (5) and a unidirectional movable electrostatic comb (4); the fixed electrostatic comb (5) is kept fixed, and the other end of the long side of the unidirectional movable electrostatic comb (4) and the transmission rod (1) are fixedly connected. The unidirectional movable electrostatic comb (4) and the transmission rod (1) are suspended structures. The unidirectional movable electrostatic comb (4) and the transmission rod (1) are moved as a whole by a continuous non-volatile adjustment structure, thereby driving the unidirectional movable electrostatic comb (4) to move closer to or away from the fixed electrostatic comb (5).

3. The on-chip continuous non-volatile adjustment structure based on MEMS according to claim 2, characterized in that: The fixed electrostatic comb (5) and the unidirectional movable electrostatic comb (4) are mainly composed of a comb handle and comb teeth periodically distributed on the comb handle. The comb handle and the other end of the long side of the transmission rod (1) are fixedly connected. The length direction of the comb handle is parallel to the short side of the transmission rod (1). Each comb tooth is arranged on the side of the comb handle away from the transmission rod (1) and is periodically arranged along the length direction of the comb handle. The length direction of each comb tooth is parallel to the long side of the transmission rod (1). One end of the comb tooth is connected to the comb handle, and the other end is not connected.

4. The on-chip continuous non-volatile adjustment structure based on MEMS according to claim 1, characterized in that: Each pair of fixed island spring structures (2, 3) is mainly composed of two fixed island spring assemblies symmetrically distributed on both sides of the long side of the transmission rod (1). Each fixed island spring assembly is mainly composed of a folding spring (3) and a fixed island (2) that supports the folding spring. The fixed island (2) remains fixed, and part of the folding spring (3) is fixedly connected to the fixed island (2), and the other part is fixedly connected to the long side of the transmission rod (1).

5. The on-chip continuous non-volatile adjustment structure based on MEMS according to claim 1, characterized in that: In the brake, two pairs of fixed island spring structures (2, 3) are distributed on both sides of the bidirectional electrostatic comb driver (7, 8, 9). The fixed island spring structures (2, 3) of the bidirectional electrostatic comb driver (7, 8, 9) and the fixed island spring structures (2, 3) in the regulator have the same structure. The bidirectional electrostatic comb driver (7, 8, 9) comprises a pair of bidirectional electrostatic comb assemblies, which are symmetrically distributed on both sides of the brake lever (6) along its length. Each bidirectional electrostatic comb assembly includes two fixed electrostatic combs (7, 9) and one bidirectional movable electrostatic comb (8). The two fixed electrostatic combs (7, 9) have the same structure as the fixed electrostatic comb (5) in the regulator. The bidirectional movable electrostatic comb (8) has a similar structure to the unidirectional movable electrostatic comb (4) in the regulator. However, the bidirectional movable electrostatic comb (8) differs in that it has symmetrical combs on both sides of the comb handle along its length. The teeth are distributed such that two fixed electrostatic combs (7, 9) are arranged on both sides of the bidirectional movable electrostatic comb (8); the end of the bidirectional movable electrostatic comb (8) near the brake rod (6) is connected to the brake rod (6), and the end away from the brake rod (6) is not connected; the end of each fixed electrostatic comb (7, 9) near the brake rod (6) is not connected, and the end away from the brake rod (6) is connected to the external circuit; one fixed electrostatic comb (7) near the brake rod (6) brake end is the brake fixed electrostatic comb (7), and the other fixed electrostatic comb (9) near the brake rod (6) limit end is the brake release fixed electrostatic comb (9).

6. The on-chip continuous non-volatile adjustment structure based on MEMS according to claim 1, characterized in that: The mechanical stopping structure (10) is a conical structure whose bottom is supported and connected to the base (11) through the buried layer (12), and the tip of the conical structure is arranged opposite to the limiting end of the brake rod (6).

7. The on-chip continuous non-volatile adjustment structure based on MEMS according to claim 1, characterized in that: The regulator and brake are arranged on the base (11), wherein the fixed electrostatic comb (5) of the unidirectional electrostatic comb driver (4, 5), the fixed island (2) of the fixed island spring structure (2, 3) and the fixed electrostatic comb (7, 9) of the bidirectional electrostatic comb driver (7, 8, 9) are all arranged on the base (11) with the bottom supported by the buried layer (12).

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