Device and method for surface acoustic wave-assisted mask electrolysis

Abstract

The present invention provides a device and method for surface acoustic wave-assisted mask electrolysis, belonging to the field of electrolytic machining. The piezoelectric ceramic of the device is pasted on a substrate. The substrate has a reaction tank, the anode workpiece is arranged below the reaction tank, and the cathode is located above the reaction tank. The electrolyte in the reaction tank is supplied by an inlet pump and pumped out by an outlet pump. Based on the device, the inlet pump and the outlet pump are turned on to circulate the electrolyte; a megasonic wave signal is introduced into the piezoelectric ceramic through a driving line, and the megasonic vibration generated by the piezoelectric ceramic propagates on the surface of the substrate and the anode workpiece in the form of a surface acoustic wave, and radiates from the surface to be machined of the anode workpiece to the electrolyte in the reaction tank; direct current is connected to the anode workpiece and the cathode through a power line to realize electrolytic machining of the anode workpiece. The present invention is simple and reliable, can improve the mass transfer effect of mask electrolytic machining, and realize high-precision machining of metal microstructures.

Description

Technical Field

[0001] The invention relates to a mask electrolytic machining method, in particular to a surface acoustic wave assisted mask electrolysis device and method, belonging to the field of electrolytic machining. Background Art

[0002] With the increasing sophistication and miniaturization of industrial products, the market demand for metal microstructures (devices) has increased dramatically. The main methods for fabricating metal microstructures include LIGA or UV-LIGA technology, mechanical micromachining, electrical discharge machining (EDM), laser machining, chemical etching, and masked electrochemical machining (MEM). Among them, masked electrochemical machining (MEM) offers advantages such as burr-free processing, no deformation, high-volume production, and low cost, making it the mainstream technology for fabricating metal microstructures, especially those that are difficult to fabricate.

[0003] The traditional masked electrochemical machining process involves placing an insulating mask pattern on the anode workpiece surface to be machined. The space between the anode workpiece and the flat cathode is filled with electrolyte. Power is then connected between the cathode and cathode to perform electrochemical machining. After removing the insulating mask, the microstructure is formed on the workpiece surface. Currently, masked electrochemical machining suffers from difficulties in discharging electrolytic products. This leads to irregular adhesion of bubbles and solid impurities to the machined surface, resulting in uneven dissolution of the anode workpiece, which directly affects the machining accuracy and surface quality of the metal microstructure.

[0004] To address the problem of poor surface quality during machining of metal microstructures, invention patent CN 107116274 A proposes a cavitation jet-assisted mask electrochemical machining method. This method utilizes a micro-water jet formed by the collapse of the cavitation jet electrolyte to expel electrolysis products, thereby improving the machined surface quality. However, due to the high energy generated by the collapse of the cavitation jet electrolyte, this method can significantly damage the mask. Invention patent CN 106312206A proposes a device and method for active mask electrochemical machining. This method places a porous metal medium in close contact with the anode workpiece. After electrolyte is pumped above the porous medium, it flows out from all sides of the porous medium, facilitating inter-electrode mass transfer and achieving a uniform flow field distribution, thereby improving machining accuracy. However, since the electrolyte is pumped in from an external source, its kinetic energy is continuously lost during the flow process. Once the machining aspect ratio reaches a certain level, the electrolyte's flow capacity is limited. Consequently, the active mask electrochemical machining method is limited in its ability to machine structures with large aspect ratios. Invention patent CN 109773292 A proposes a device and method for megasonic mask electrochemical machining of high aspect ratio microstructures. This method uses piezoelectric ceramics attached to the back of the anode workpiece, radiates megasonic waves into the electrolyte, and promptly discharges the etching products through the acoustic jet effect generated by the megasonic waves. Because megasonics has strong penetrating ability and low cavitation effect, this method does not damage the microstructure and the film, and can improve the accuracy of mask electrochemical machining. However, due to the directionality of megasonics, the area of ​​action of megasonics depends on the size of the piezoelectric ceramic. When the anode workpiece is too large, it is difficult to produce piezoelectric ceramics of the same size as the anode workpiece, so the size of the workpiece that can be machined by this method is limited. Summary of the Invention

[0005] To overcome the low machining precision and poor surface quality associated with conventional masked electrochemical machining (MEM), the present invention provides a surface acoustic wave (SAW)-assisted masked electrochemical process. This method introduces SAWs into the process in a specific manner. The propagation of SAWs across the workpiece surface promotes the flushing of the electrolyte on the machined surface, improving the machining precision and surface quality of masked electrochemical machining, enabling high-precision machining of metal microstructures.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A surface acoustic wave-assisted mask electrolysis device includes a waterproof cover 1, a hose 2, an inlet pump 3, an outlet pump 4, a power cord 5, a drive line 6, a cathode 7, an anode assembly 8, an electrolysis system 9, and a swing door 10. The positive pole of the power cord 5 is connected to the anode workpiece 81 in the anode assembly 8, and the negative pole is connected to the cathode 7. The inlet pump 3 quantitatively transports electrolyte 11 from a reservoir 91 in the electrolysis system 9 to a reaction tank 821 in the anode assembly 8 through the hose 2. The outlet pump 4 transports the reacted electrolyte back to the reservoir 91 through the hose 2. The water cover 1 shields the reservoir 91. The drive line 6 connects to the piezoelectric ceramic 83 in the anode assembly 8. The hose 2, inlet pump 3, outlet pump 4, power cord 5, drive line 6, cathode 7, and anode assembly 8 are all placed in the electrolysis system 9. The swing door 10 is connected to the electrolysis system 9 via a hinge.

[0008] The electrolysis system 9 is divided into four layers by a plate structure (the first layer is filled with electrolyte. The second layer has electrolyte only in the water pipe. The third layer has electrolyte only in the reaction tank 821. The fourth layer is a small amount of electrolyte that has leaked out and is not full). From top to bottom, they are:

[0009] The first layer is the liquid reservoir 91, a semi-sealed structure with an open top, used to store electrolyte 11. The bottom of the liquid reservoir 91 is provided with a water outlet 911 and a water inlet 912. The water outlet 911 is connected to the water inlet pump 3 via a hose 2, while the water inlet 912 is connected to the water outlet pump 4. A water cover 1 is placed on top of the liquid reservoir 91. The second layer is the storage layer 92, which houses the water inlet pump 3, the water outlet pump 4, and the cathode 7. The bottom of the storage layer 92 features a sponge 921 for accommodating the water inlet pump 3 and the water outlet pump 4. Two fixing holes 922 on the bottom of the storage layer 92 are used to secure the hose 2. The water inlet pump 3 transfers a fixed amount of electrolyte from the liquid reservoir 91 to the reaction layer 93 via the hose 2, while the water outlet pump 4 transfers electrolyte from the reaction layer 93 back to the liquid reservoir 91 via the hose 2. A threaded hole 923 on the bottom of the storage layer 92 mates with the threads 701 on the top of the cathode 7, allowing the cathode to penetrate into the reaction layer 93. The third layer is the reaction layer 93 (the bottom of the reaction layer 93 is a flat plate with three holes. The holes serve two purposes: to form ribs to support the anode assembly; and to allow electrolyte leakage through the holes to flow into the next layer). This is where the chemical reaction occurs: the bottom of the reaction layer 93 is a plate structure with three square holes. Ribs 931 are formed between adjacent square holes. The anode assembly 8 is placed on two ribs 931 of the reaction layer 93. After the two hoses 2 fixed by the storage layer 92 are inserted into the reaction layer 93, the ends of the hoses 2 are horizontal and parallel to the top of the reaction tank 821 of the anode assembly 8. Because the flow rate of the water outlet pump 4 is greater than that of the water inlet pump 3, the electrolyte exactly fills the reaction tank 821 and does not overflow. After the cathode 7 fixed by the storage layer 92 is inserted into the reaction layer 93, the end of the cathode 7 is parallel to the top of the reaction tank 821 of the anode assembly 8, so that the cathode 7 contacts the electrolyte. If the electrolyte overflows the reaction tank 821 due to an unexpected situation, the electrolyte flows into the leak-proof layer 94 through the three square holes at the bottom of the reaction layer 93. The fourth layer is a leak-proof layer 94 , which is a semi-sealed structure located below the reaction layer 93 and prevents the electrolyte 11 from flowing out of the electrolysis system 91 during the reaction process.

[0010] Furthermore, the anode assembly 8 mainly includes an anode workpiece 81, a substrate 82, and a piezoelectric ceramic 83. The substrate 82 is provided with a square through hole 821, which is a reaction tank 821 for the electrochemical reaction. The anode workpiece 81 and the piezoelectric ceramic 83 are pasted on the substrate 82. The anode workpiece 81 is connected to the positive pole of the power line 5, and the surface to be processed 811 of the anode workpiece 81 is exposed to the electrolyte 11 through the square through hole 821 to undergo an oxidation reaction, that is, electrolytic etching processing is performed, and the non-processed surface 812 has an insulating layer. The piezoelectric ceramic 83 is connected to the driving line 6, and the frequency of the piezoelectric ceramic 83 is above 1 MHz, that is, the frequency of the surface acoustic wave is above 1 MHz. The low cavitation effect of the high-frequency sound wave can ensure that the sound wave does not damage the adhesive film during the mask electrolytic processing.

[0011] Furthermore, the cover edge 101 of the water cover 1 is made of rubber material.

[0012] Furthermore, one end of the cathode 7 has a thread 701 .

[0013] A method for surface acoustic wave-assisted mask electrolysis, in which the surface acoustic wave propagating on the surface to be processed 811 of the etched workpiece is radiated to the electrolyte 11, generating high-frequency disturbances and an acoustic flow jet effect. The vibration direction of the surface acoustic wave has a parallel component and a perpendicular component to the solid-liquid interface. On the one hand, the parallel component generates tangential stress on the electrolyte 11, causing the electrolyte 11 at the solid-liquid interface to form micro-eddies, promoting the flushing effect of the electrolyte 11 on the surface to be processed 811, and thinning the fluid boundary layer. On the other hand, the perpendicular component generates normal stress on the electrolyte 11, ejecting and driving away the electrolyte 11 near the surface to be processed 811, promoting the timely discharge of electrolysis products and the timely renewal of fresh electrolyte 11. In this way, the etching products generated in the etched microstructure during electrolytic processing are ejected under the action of the surface acoustic wave acoustic flow, greatly reducing concentration polarization, improving the surface quality of mask electrolytic processing, and thus realizing mirror processing of metal microstructures. Specifically comprising the following steps:

[0014] S1. A photoresist mask pattern 813 is formed on the surface to be processed 811 of the anode workpiece 81. The photoresist film is patterned through standard processes such as photoresist spreading, photoresist exposure, and development to expose the conductive surface to be processed 811.

[0015] S2. Paste the patterned anode workpiece 81 and the piezoelectric ceramic 83 onto the substrate 82 to form the anode assembly 8. Select a suitable position and place the anode assembly 8 on the two ribs 931 of the reaction layer 93 of the electrolysis system 9.

[0016] S3. Select a cathode 7 of appropriate size and adjust the distance between the cathode and anode by adjusting the fit between the thread 701 and the threaded hole 923.

[0017] Furthermore, the size and shape of the cathode can be designed according to the size of the photoresist mask pattern 813 to reduce the adverse effects of the electric field edge effect on the electrolytic machining accuracy.

[0018] S4. Turn on the water inlet pump 3 and the water outlet pump 4. The water inlet pump 3 introduces electrolyte into the reaction tank 821. The flow rate of the water outlet pump 4 is greater than that of the water inlet pump 3 to prevent the electrolyte from overflowing the reaction tank 821.

[0019] S5. A megasonic wave signal is input to the piezoelectric ceramic 83 through the driving line 6. The megasonic vibration generated by the piezoelectric ceramic 83 propagates on the surface of the substrate 82 and the anode workpiece 81 in the form of a surface acoustic wave, and is radiated from the surface to be processed 811 of the anode workpiece 81 to the electrolyte 11.

[0020] Furthermore, the frequency of the piezoelectric ceramic is above 1 MHz, that is, the frequency of the surface acoustic wave is above 1 MHz. The low cavitation effect of high-frequency acoustic waves above 1 MHz can reduce the damage of cavitation bubbles to the mask pattern 813 and reduce the impact of bubbles on the accuracy of mask electrochemical machining.

[0021] S6. Direct current is supplied to the anode workpiece 81 and cathode 7 via power cord 5, enabling electrolytic machining of the anode workpiece 81. Surface acoustic waves propagating from the machined surface 811 of the anode workpiece 81 radiate into the electrolyte in the reaction tank 821, forming micro-eddies in the electrolyte that the machined surface 811 contacts. These micro-eddies expel electrolysis products from the anode surface into the reaction tank 821, preventing them from adhering to the workpiece surface and affecting machining quality. Electrolysis products in the reaction tank 821 are removed by the outlet pump 4, while the inlet pump 3 promptly supplies fresh electrolyte.

[0022] The beneficial effects of the present invention are:

[0023] (1) Surface acoustic waves have a good mass transfer effect and help improve machining accuracy. When surface waves propagate, the vibration of the surface to be machined has a parallel component and a perpendicular component to the solid-liquid interface. On the one hand, the parallel component generates tangential stress on the electrolyte, causing the electrolyte at the solid-liquid interface to form micro-eddies, promoting the electrolyte to flush the machined surface and thinning the fluid boundary layer. On the other hand, the perpendicular component generates normal stress on the electrolyte, ejecting the electrolyte near the machined surface, promoting the timely discharge of electrolysis products and the timely renewal of fresh electrolyte.

[0024] (2) Surface acoustic waves are easier to integrate, which helps save device space. A small piece of piezoelectric ceramic can form surface acoustic waves on the surface of a larger workpiece, promoting mass transfer during mask electrochemical machining.

[0025] (3) Surface acoustic waves do not damage the film and microstructure. The sound source has an operating frequency of more than 1MHz, and has the characteristics of high energy density, strong penetration ability, and small cavitation effect. While generating high-frequency disturbances, it does not damage various microstructures and micro devices.

[0026] (4) Surface acoustic waves act directly on the workpiece, which has a stronger effect and helps to increase the depth of mask electrochemical processing. Surface acoustic waves radiate from the anode workpiece into the electrolyte, which is an inside-out action mode. The effect is stronger and can also play a good mass transfer effect in microstructures with a large depth-to-width ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is an overall view of the surface acoustic wave assisted mask electrolysis device of the present invention;

[0028] Figure 2 This is the axonometric drawing of water cover 1;

[0029] Figure 3 It is the axonometric drawing of cathode 7;

[0030] Figure 4 is an axonometric view of the anode assembly 8;

[0031] Figure 5 It is an axonometric view of the anode workpiece 81;

[0032] Figure 6 It is an axonometric view of the base plate 82;

[0033] Figure 7 (a) is an axonometric view of the electrolysis system 9; Figure 7 (b) Figure 7 (a) A partial enlarged view;

[0034] Figure 8 This is a schematic diagram of the principle of surface acoustic wave assisted mask electrochemical machining;

[0035] In the figure: 1 waterproof cover, 2 hose, 3 water inlet pump, 4 water outlet pump, 5 power line, 6 drive line, 7 cathode, 8 anode assembly, 9 electrolysis system, 10 swing door, 11 electrolyte.

[0036] 81 anode workpiece, 82 substrate, 83 piezoelectric ceramic, 91 liquid storage tank, 92 storage layer, 93 reaction layer, 94 leak-proof layer.

[0037] 101 lid edge, 701 thread, 811 surface to be processed, 812 non-processed surface, 813 mask pattern, 821 reaction tank, 911 water outlet, 912 water inlet, 921 sponge, 922 fixing hole, 923 threaded hole, 931 rib. DETAILED DESCRIPTION

[0038] The core concept of this invention is to provide a device and method for surface acoustic wave-assisted masked electrolysis, which introduces surface acoustic waves into the masked electrolysis process in a specific manner. The propagation of surface acoustic waves on the workpiece surface promotes the flushing effect of the electrolyte on the machined surface, improving the surface quality of masked electrolysis and enhancing the machining accuracy of metal microstructures.

[0039] The present invention will be further described below in conjunction with the embodiments shown in the accompanying drawings. It should be understood that the embodiments described herein are merely some examples, not all, of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0040] A surface acoustic wave assisted mask electrolysis device such as Figure 1 shown.

[0041] Figure 1This is an overall view of the surface acoustic wave-assisted mask electrolysis device of the present invention, which primarily includes a waterproof cover 1, a hose 2, an inlet pump 3, an outlet pump 4, a power cord 5, a drive line 6, a cathode 7, an anode assembly 8, an electrolysis system 9, and a swing door 10. The positive pole of the power cord 5 is connected to the anode workpiece 81 in the anode assembly 8, and the negative pole is connected to the cathode 7. The inlet pump 3 quantitatively transports electrolyte 11 from the reservoir 91 in the electrolysis system 9 to the reaction tank 821 in the anode assembly 8 through the hose 2. The outlet pump 4 transports the reacted electrolyte back to the reservoir 91 through the hose 2. The water cover 1 shields the reservoir 91. The drive line 6 connects to the piezoelectric ceramic 83 in the anode assembly 8. The hose 2, inlet pump 3, outlet pump 4, power cord 5, drive line 6, cathode 7, and anode assembly 8 are all placed in the electrolysis system 9. The swing door 10 is connected to the electrolysis system 9 via a hinge.

[0042] Figure 2 This is an axonometric view of the water cover 1 , wherein the cover edge 101 of the water cover 1 is made of rubber material.

[0043] Figure 3 This is an isometric view of the cathode 7 , which has a thread 701 at one end.

[0044] Figure 4 This is an isometric view of anode assembly 8, which primarily includes anode workpiece 81, substrate 82, and piezoelectric ceramic 83. Anode workpiece 81 and piezoelectric ceramic 83 are attached to substrate 82. Anode workpiece 81 is connected to the positive terminal of power line 5. Piezoelectric ceramic 83 is connected to drive line 6. The frequency of piezoelectric ceramic 83 is above 1 MHz.

[0045] Figure 5 This is an axonometric view of the anode workpiece 81 . The surface 811 to be machined of the anode workpiece 81 is exposed to the electrolyte to undergo oxidation reaction, and the non-machined surface 812 has an insulating layer.

[0046] Figure 6 82 is an axonometric view of the substrate 82 . The substrate 82 has a square through hole 821 , which is a reaction tank 821 for electrochemical reaction.

[0047] Figure 7This is an axonometric view of the electrolysis system 9. The electrolysis system 9 can be divided into four layers. The first layer is the liquid reservoir 91, a semi-sealed structure with an open top, used to store electrolyte. The bottom of the liquid reservoir 91 has a water outlet 911 and a water inlet 912. The water outlet 911 is connected to the water inlet pump 3 via a hose 2, and the water inlet 912 is connected to the water outlet pump 4. The second layer is the storage layer 92, which is used to accommodate the water inlet pump 3, the water outlet pump 4, and the cathode 7. The bottom of the storage layer 92 has a sponge 921 for accommodating the water inlet pump 3 and the water outlet pump 4. The two fixing holes 922 on the bottom of the storage layer 92 are used to secure the hoses to prevent them from swinging, and the threaded holes 923 mate with the threads 701 of the cathode 7. The third layer is the reaction layer 93, with the anode assembly 8 placed on two ribs 931 of the reaction layer 93. The fourth layer is the leakproof layer 94, a semi-sealed structure with an open top, which prevents the electrolyte from leaking during the reaction process.

[0048] A surface acoustic wave-assisted mask electrolysis method is implemented by the following steps:

[0049] S1. A photoresist mask pattern 813 is formed on the surface to be processed 811 of the anode workpiece 81. The photoresist film is patterned through standard processes such as photoresist spreading, photoresist exposure, and development to expose the conductive surface to be processed 811.

[0050] S2. Paste the patterned anode workpiece 81 and the piezoelectric ceramic 83 onto the substrate 82 to form the anode assembly 8. Select a suitable position and place the anode assembly 8 on the two ribs 931 of the reaction layer 93 of the electrolysis system 9.

[0051] S3. Select a cathode 7 of appropriate size and adjust the distance between the cathode and anode by adjusting the fit between the thread 701 and the threaded hole 923.

[0052] In particular, the size and shape of the cathode can be designed according to the size of the photoresist mask pattern 813 to reduce the adverse effects of the electric field edge effect on the electrochemical machining accuracy.

[0053] S4. Turn on the water inlet pump 3 and the water outlet pump 4. The water inlet pump 3 introduces electrolyte into the reaction tank 821. The flow rate of the water outlet pump 4 is greater than that of the water inlet pump 3 to prevent the electrolyte from overflowing the reaction tank 821.

[0054] S5. A megasonic wave signal is applied to the piezoelectric ceramic 83 via the drive line 6. The megasonic vibrations generated by the piezoelectric ceramic 83 propagate in the form of surface acoustic waves on the substrate 82 and the anode workpiece 81, radiating from the surface 811 to be machined of the anode workpiece 81 to the electrolyte 11. The frequency of the piezoelectric ceramic is above 1 MHz, meaning that the frequency of the surface acoustic waves is above 1 MHz. The low cavitation effect of high-frequency acoustic waves above 1 MHz reduces damage to the mask pattern 813 caused by cavitation bubbles and reduces the impact of bubbles on the accuracy of mask electrochemical machining.

[0055] S6. Direct current is supplied to the anode workpiece 81 and cathode 7 via power cord 5, enabling electrolytic machining of the anode workpiece 81. Surface acoustic waves propagating from the machined surface 811 of the anode workpiece 81 radiate into the electrolyte in the reaction tank 821, forming micro-eddies in the electrolyte that the machined surface 811 contacts. These micro-eddies expel electrolysis products from the anode surface into the reaction tank 821, preventing them from adhering to the workpiece surface and affecting machining quality. Electrolysis products in the reaction tank 821 are removed by the outlet pump 4, while the inlet pump 3 promptly supplies fresh electrolyte.

[0056] It should be noted that:

[0057] (1) The present invention provides a device for surface acoustic wave-assisted mask electrolysis and proposes a mirror processing method for metal microstructures using surface acoustic wave-assisted mask electrolysis. The vibrations excited by the piezoelectric ceramic propagate on the surfaces of the substrate and the anode workpiece in the form of surface acoustic waves. The surface acoustic waves propagated by the substrate and the anode workpiece radiate into the electrolyte, forming micro-eddies and macroscopic flows of the electrolyte, promoting the flushing effect of the electrolyte on the processed surface, facilitating the timely discharge of electrolysis products and the timely renewal of fresh electrolyte, thereby improving the processing accuracy of the metal microstructure.

[0058] (2) Surface acoustic wave action in the present invention: The vibration of the surface to be machined has a component parallel to the solid-liquid interface and a component perpendicular to it. On the one hand, the parallel component generates tangential stress on the electrolyte, causing micro-eddies to form in the electrolyte at the solid-liquid interface, promoting the electrolyte's scouring effect on the machined surface and thinning the fluid boundary layer. On the other hand, the perpendicular component generates normal stress on the electrolyte, ejecting and driving away the electrolyte near the machined surface, promoting the timely discharge of electrolysis products and the timely replacement of fresh electrolyte.

[0059] This method can significantly improve the deep etching capability and uniformity of mask electrochemical microstructures, ensuring the performance of microstructure devices. 2 Under the processing conditions of an electrolysis time of 60 seconds and a 15% sodium chloride electrolyte, a microfluidic chip mold was processed. The device and method using surface acoustic wave-assisted mask electrolysis overcame the problems of insufficient processing depth and poor uniformity that have always existed in the mask electrolysis processing process. The average processing depth of the microfluidic chip mold was 60μm, and the depth unevenness was 33%. Compared with the conventional mask electrolysis process without surface wave action (average processing depth of 30μm and depth unevenness of 85%), the etching depth increased by 100% and the unevenness decreased by 61% (the lower the unevenness, the higher the processing accuracy). It can be seen that the method of the present invention can effectively improve processing accuracy.

[0060] In summary, the above method provided in the embodiment of the present application can be used to discharge the etching products in a timely manner with the help of the micro-eddies and acoustic jet effects generated by surface acoustic waves in the electrolyte, thereby improving the surface quality of the mask electrolytic processing and achieving the processing accuracy of the metal microstructure.

[0061] The above-described embodiments merely express the implementation methods of the present invention, but should not be understood as limiting the scope of the patent of the present invention. It should be pointed out that for those skilled in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A surface acoustic wave assisted mask electrolysis device, characterized in that: The device comprises a waterproof cover (1), a hose (2), a water inlet pump (3), a water outlet pump (4), a power line (5), a drive line (6), a cathode (7), an anode assembly (8), an electrolysis system (9), and a swing door (10); the positive electrode of the power line (5) is connected to the anode workpiece (81) in the anode assembly (8), and the negative electrode is connected to the cathode (7); the water inlet pump (3) quantitatively transports the electrolyte (11) from the liquid storage tank (91) in the electrolysis system (9) to the anode through the hose (2). The reaction tank (821) in the assembly (8) and the water outlet pump (4) transport the reacted electrolyte back to the liquid storage tank (91) through the hose (2), and the waterproof cover (1) shields the liquid storage tank (91); the driving line (6) is connected to the piezoelectric ceramic (83) in the anode assembly (8); the hose (2), the water inlet pump (3), the water outlet pump (4), the power line (5), the driving line (6), the cathode (7), and the anode assembly (8) are all placed in the electrolysis system (9), and the swing door (10) is connected to the electrolysis system (9); The anode assembly (8) includes an anode workpiece (81), a substrate (82), and a piezoelectric ceramic (83); the substrate (82) is provided with a through hole (821), and the through hole (821) is a reaction tank (821) for an electrochemical reaction; the anode workpiece (81) and the piezoelectric ceramic (83) are attached to the substrate (82); the anode workpiece (81) is connected to the positive pole of the power line (5), and the surface to be processed (811) of the anode workpiece (81) is exposed to the electrolyte (11) through the through hole (821) to undergo an oxidation reaction, i.e., electrolytic etching is performed, and the non-processed surface (812) has an insulating layer; the piezoelectric ceramic (83) is connected to the driving line (6); A megasonic wave signal is input to the piezoelectric ceramic (83) via a driving line (6), and the megasonic vibration generated by the piezoelectric ceramic (83) propagates on the surface of the substrate (82) and the anode workpiece (81) in the form of a surface acoustic wave, and is radiated from the surface to be processed (811) of the anode workpiece (81) to the electrolyte (11).

2. The surface acoustic wave assisted mask electrolysis device according to claim 1, characterized in that: The electrolysis system (9) is divided into four layers by a plate structure, which are as follows from top to bottom: The first layer is a liquid storage tank (91), which is a semi-sealed structure with an opening at the top, and is used to store electrolyte (11); a water outlet (911) and a water inlet (912) are provided on the bottom surface of the liquid storage tank (91); the water outlet (911) is connected to the water inlet pump (3) via a hose (2), and the water inlet (912) is connected to the water outlet pump (4); a waterproof cover (1) is placed on the top of the liquid storage tank (91); The second layer is a storage layer (92) for placing the water inlet pump (3), the water outlet pump (4), and the cathode (7): a sponge (921) is provided on the bottom surface of the storage layer (92) for placing the water inlet pump (3) and the water outlet pump (4); two fixing holes (922) on the bottom surface of the storage layer (92) are used to fix the hose (2); the water inlet pump (3) quantitatively transports the electrolyte in the liquid storage tank (91) to the reaction layer (93) through the hose (2); the water outlet pump (4) transports the electrolyte in the reaction layer (93) back to the liquid storage tank (91) through the hose (2); the threaded hole (923) on the bottom surface of the storage layer (92) cooperates with the thread (701) on the top of the cathode (7), and the cathode is inserted into the reaction layer (93); The third layer is the reaction layer (93), which is the location where the chemical reaction takes place: the reaction layer (93) is a plate structure with three holes at the bottom, with ribs (931) formed between two adjacent holes, and the anode assembly (8) is placed on the two ribs (931) of the reaction layer (93); after the two hoses (2) fixed by the storage layer (92) are inserted into the reaction layer (93), the ends of the hoses (2) are horizontal and parallel to the top of the reaction tank (821) of the anode assembly (8), and the electrolyte fills the reaction tank (821) and does not overflow; after the cathode (7) fixed by the storage layer (92) is inserted into the reaction layer (93), the end of the cathode (7) is parallel to the top of the reaction tank (821) of the anode assembly (8), so that the cathode (7) just contacts the electrolyte; when the electrolyte overflows the reaction tank (821), the electrolyte flows into the leak-proof layer (94) through the three holes at the bottom of the reaction layer (93); The fourth layer is a leakproof layer (94), which is a semi-sealed structure located below the reaction layer (93) to prevent the electrolyte (11) from flowing out of the electrolysis system (9) during the reaction process.

3. A method for surface acoustic wave-assisted mask electrolysis, characterized in that: The method is implemented based on the device according to any one of claims 1 to 2, wherein the surface acoustic wave propagating on the surface (811) of the etched workpiece to be processed is radiated to the electrolyte (11), generating high-frequency disturbance and acoustic flow jet effect; The vibration direction of the surface acoustic wave has a parallel component and a perpendicular component to the solid-liquid interface: on the one hand, the parallel component generates a tangential stress on the electrolyte (11), causing the electrolyte (11) at the solid-liquid interface to form a micro-eddy current, promoting the electrolyte (11) to flush the surface to be processed (811), and thinning the fluid boundary layer; on the other hand, the perpendicular component generates a normal stress on the electrolyte (11), ejecting and driving away the electrolyte (11) near the surface to be processed (811), promoting the timely discharge of electrolysis products and the timely renewal of fresh electrolyte (11); The etching products generated in the etched microstructure during electrochemical machining are ejected under the action of surface acoustic wave acoustic streaming, reducing concentration polarization, improving the surface quality of mask electrochemical machining, and thus realizing the machining of metal microstructures.

4. The method of surface acoustic wave assisted mask electrolysis according to claim 3, characterized in that: The following steps are involved: S1. A photoresist mask pattern (813) is formed on the surface (811) of the anode workpiece (81) to be processed. The photoresist is exposed and developed using a standard process to pattern the film and expose the conductive surface (811) to be processed. S2. Pasting the patterned anode workpiece (81) and the piezoelectric ceramic (83) onto the substrate (82) to form an anode assembly (8), selecting a suitable position, and placing the anode assembly (8) on two ribs (931) of the reaction layer (93) of the electrolysis system (9); S3. Select a cathode of suitable size (7) and adjust the appropriate distance between the cathode and anode; S4. Open the water inlet pump (3) and the outlet pump (4). The water inlet pump (3) is used to pass the electrolyte into the reaction tank (821). The flow rate of the outlet pump (4) is greater than that of the water inlet pump (3) to prevent the electrolyte from overflowing the reaction tank (821). S5. A megasonic wave signal is fed into the piezoelectric ceramic (83) via the driving line (6). The megasonic vibration generated by the piezoelectric ceramic (83) propagates on the surfaces of the substrate (82) and the anode workpiece (81) in the form of a surface acoustic wave, and is radiated from the surface to be processed (811) of the anode workpiece (81) to the electrolyte (11); S6. Direct current is connected to the anode workpiece (81) and the cathode (7) via a power cord (5) to achieve electrolytic machining of the anode workpiece (81); surface acoustic waves propagating from the surface to be machined (811) of the anode workpiece (81) are radiated to the electrolyte in the reaction tank (821), forming micro-eddies in the electrolyte in contact with the surface to be machined (811), and the micro-eddies discharge the electrolysis products on the anode surface into the reaction tank (821), thereby preventing the electrolysis products from adhering to the workpiece surface and affecting the machining quality; the electrolysis products in the reaction tank (821) are taken away by the outlet pump (4), and the inlet pump (3) promptly supplies fresh electrolyte.

5. The method of surface acoustic wave assisted mask electrolysis according to claim 4, characterized in that: In the step S3, the size and shape of the cathode are designed according to the size of the photoresist mask pattern (813).

6. The method of surface acoustic wave assisted mask electrolysis according to claim 4, characterized in that: In the step S5, the frequency of the piezoelectric ceramic is above 1 MHz.

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