Microfluidics-assisted glass microchannel wet etching processing device and method

Abstract

The invention relates to the technical field of glass etching, in particular to a microfluidics-assisted glass microchannel wet etching processing device and method. The invention discloses a micro-fluidic assisted wet etching processing device for a glass micro-channel. The micro-fluidic assisted wet etching processing device comprises a first storage container, a second storage container, a first peristaltic pump, a second peristaltic pump, a micro-fluidic etching chip, an ultrasonic temperature control water bath device and a recovery container, the microfluidics-assisted glass microchannel wet etching processing device has the advantages that the controllability of the etching process is good, the concentration of an etching agent can be adjusted in real time, the dosage of the etching agent is small, the mass transfer efficiency is high, the etching rate is high, the anisotropy and morphology quality of the etched glass microchannel are good, and the etching precision is high; the technical problems that an existing wet etching processing device cannot adjust the concentration of an etching solution in real time, and is poor in solution flow, low in mass transfer efficiency, low in etching rate, large in etching waste liquid amount, large in etching side wall inclination angle and poor in consistency are solved.

Description

Technical Field

[0001] This invention relates to the field of glass etching technology, and in particular to a microfluidic-assisted wet etching apparatus and method for glass microchannels. Background Technology

[0002] Glass microchannels possess many superior properties and have broad application prospects in microelectromechanical devices (MEMS) and sensors. The fabrication methods for glass microchannels can be divided into dry etching methods and wet etching methods. Dry etching methods mainly include ion beam etching (IBE), reactive ion etching (RIE), and inductively coupled plasma (ICP) etching, which can fabricate microstructures with high transfer pattern fidelity; however, the etching efficiency is slow, and the method is expensive and complex. Wet etching methods refer to etching a quartz substrate using a chemical solution. Due to its isotropic nature, traditional wet etching can only form microstructures with simple shapes and low precision.

[0003] In contrast, laser-induced wet etching, as a novel wet etching method for etching microstructures on glass semiconductor materials, offers advantages such as simple process, low cost, and high efficiency. Laser-induced wet etching refers to selective wet chemical etching of glass substrates treated with ultrafast lasers. It utilizes lasers to induce phase transitions in the glass material, increasing the etching rate in the processed area. Subsequently, combined with wet etching processes, selective material removal is performed in designated areas, achieving the fabrication of glass microchannels. Therefore, laser-induced wet etching is currently the main method for fabricating glass microchannels.

[0004] However, conventional laser-induced wet etching methods typically use a single etching solution with a fixed concentration for each etching pass. Furthermore, the etching solution is often static within the etching container, meaning it doesn't flow. The glass substrate is simply immersed in the etching solution, and the concentration cannot be adjusted in real time. This results in poor solution flow, low mass transfer efficiency, and long etching times. Consequently, problems arise such as large sidewall angles, poor consistency, low etching rates, and excessive etching waste. Therefore, etching controllability is poor, etching quality cannot be precisely controlled, and fabrication efficiency is low. Summary of the Invention

[0005] In response to the problems raised in the background technology, the present invention aims to provide a microfluidic-assisted wet etching apparatus for glass microchannels. This apparatus offers advantages such as good controllability of the etching process, real-time adjustment of the etchant concentration, low etchant consumption, high mass transfer efficiency, high etching rate, good anisotropy and morphological quality of the etched glass microchannels, and high etching precision. It solves the technical problems of existing wet etching apparatuses, which cannot adjust the etching solution concentration in real time, resulting in poor solution flow, low mass transfer efficiency, low etching rate, excessive etching waste, large etching sidewall inclination angles, and poor consistency.

[0006] Another objective of this invention is to propose a microfluidic-assisted wet etching method for glass microchannels applied to the aforementioned glass microchannel wet etching apparatus. This method offers good controllability of the etching process, requires less etchant, has high mass transfer efficiency, high etching rate, and produces glass microchannels with good anisotropy and morphological quality, as well as high etching precision.

[0007] Another objective of this invention is to propose a microfluidic-assisted wet etching method for glass microchannels applied to the aforementioned glass microchannel wet etching apparatus. This method ensures unobstructed flow of the etching fluid, guarantees etching effect, avoids mixing of etchants of different concentrations and compositions within the etching fluid flow channel, thus preventing interference with etching quality and effectively improving etching precision.

[0008] The above-mentioned technical objective of the present invention is achieved through the following technical solution: A microfluidic-assisted wet etching apparatus for glass microchannels includes a first storage container, a second storage container, a first peristaltic pump, a second peristaltic pump, a microfluidic etching chip, an ultrasonic temperature-controlled water bath, and a recovery container. The first and second storage containers are used to store etching agents with different compositions and concentrations. The microfluidic etching chip is disposed within the ultrasonic temperature-controlled water bath. The microfluidic etching chip includes a bonded glass substrate and a channel substrate. The glass substrate is pre-etched by laser to form pre-etched microchannels. The channel substrate has an inlet and an outlet. The inlet end of the pre-etched microchannel is connected to the inlet, and the outlet end of the pre-etched microchannel is connected to the outlet to form an etching liquid channel. The first storage container is connected to the first input terminal of the first peristaltic pump via a first inlet main pipe. The first inlet main pipe is equipped with a first micro valve. The first output terminal of the first peristaltic pump is connected to the inlet via a first inlet branch pipe. The outlet is connected to the second input terminal of the first peristaltic pump via a first outlet branch pipe. The second output terminal of the first peristaltic pump is connected to the recovery container via a first recovery liquid pipe. The first recovery liquid pipe is equipped with a second micro valve. A first circulation pipe is connected between the second output terminal of the first peristaltic pump and the second micro valve, and between the first micro valve and the first input terminal of the first peristaltic pump. The first circulation pipe is equipped with a third micro valve. The second storage container is connected to the third input terminal of the second peristaltic pump via a second inlet main pipe. The second inlet main pipe is equipped with a fourth micro valve. The third output terminal of the second peristaltic pump is connected to the inlet via a second inlet branch pipe. The outlet is connected to the fourth input terminal of the second peristaltic pump via a second outlet branch pipe. The fourth output terminal of the second peristaltic pump is connected to the recovery container via a second recovery liquid pipe. The second recovery liquid pipe is equipped with a fifth micro valve. A second circulation pipe is connected between the fourth output terminal of the second peristaltic pump and the fifth micro valve, and between the fourth micro valve and the third input terminal of the second peristaltic pump. The second circulation pipe is equipped with a sixth micro valve.

[0009] Optionally, it also includes a third storage container and a third liquid inlet pipe. The third storage container is used to store the cleaning and protective agent. The input end of the third liquid inlet pipe is disposed in the third storage container. The output end of the third liquid inlet pipe is connected to the first liquid inlet pipe, and the output end of the third liquid inlet pipe is located between the first micro valve and the first input end of the first peristaltic pump. The third liquid inlet main pipe is equipped with a seventh micro valve.

[0010] Optionally, the pre-etched microchannel of the glass substrate is a glass microgroove or a 3D microchannel, and the flow channel substrate is disposed on the upper end surface of the glass substrate. The flow channel substrate is also provided with auxiliary flow channels, and the auxiliary flow channels are respectively connected between the liquid inlet and the liquid inlet end of the pre-etched microchannel and between the liquid outlet end of the pre-etched microchannel and the liquid outlet.

[0011] Optionally, the pre-etched microchannels of the glass substrate include a plurality of arrayed glass vias, the flow channel substrate includes an upper flow channel substrate and a lower flow channel substrate, the upper flow channel substrate is disposed on the upper end face of the glass substrate, the liquid inlet is disposed on the upper flow channel substrate, the lower flow channel substrate is disposed on the lower end face of the glass substrate, and the liquid outlet is disposed on the lower flow channel substrate. The upper flow channel substrate is provided with a dispersion microchannel, the liquid inlet end of the dispersion microchannel is connected to the liquid inlet, and the liquid outlet end of the dispersion microchannel is provided in a one-to-one correspondence with the liquid inlet end of the glass through hole. The lower flow channel substrate is provided with a converging microchannel, and the liquid inlet end of the converging microchannel is provided in a one-to-one correspondence with the liquid outlet end of the glass through hole. The liquid outlet end of the converging microchannel is connected to the liquid outlet.

[0012] Optionally, it also includes a micro mixer, which has two inlet ends. The first inlet branch is connected to one of the inlet ends of the micro mixer, and the second inlet branch is connected to the other inlet end of the micro mixer. The outlet end of the micro mixer is connected to the inlet.

[0013] Optionally, it also includes a micro-CCD camera, which is disposed outside the ultrasonic temperature-controlled water bath device, with the imaging end of the micro-CCD camera facing the ultrasonic temperature-controlled water bath device, and the position of the micro-CCD camera aligned with the microfluidic etching chip. The microfluidic etching chip is positioned at the center of the ultrasonic temperature-controlled water bath device.

[0014] Optionally, it also includes an industrial control computer, wherein the first peristaltic pump, the second peristaltic pump, the ultrasonic temperature-controlled water bath device, the first micro valve, the second micro valve, the third micro valve, the fourth micro valve, the fifth micro valve, the sixth micro valve and the seventh micro valve are respectively connected to the industrial control computer.

[0015] A microfluidic-assisted wet etching method for glass microchannels, applied to the aforementioned microfluidic-assisted wet etching apparatus for glass microchannels, comprises the following steps: Step S1: Pretreatment of glass substrate: Clean and dry the glass substrate. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate, and laser processing forms pre-etched microchannels on the glass substrate; Step S3, Microfluidic etching chip fabrication: The glass substrate and the flow channel substrate are bonded together to obtain the microfluidic etching chip; Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etchant A to the first storage container and etchant B to the second storage container. Start the ultrasonic temperature-controlled water bath device and place the microfluidic etching chip in the ultrasonic temperature-controlled water bath device. Step S42, Glass microchannel etching mode a: Start the first peristaltic pump, turn off the second peristaltic pump, open the first microvalve to fill the etching liquid channel with etchant A; close the first microvalve, open the third microvalve to allow etchant A to circulate within the etching liquid channel; Step S43, Etching agent switching mode: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, close the third micro valve, and open the second micro valve and the fourth micro valve to replace etchant A in the etching liquid flow channel with etchant B; Step S44, Glass microchannel etching mode b: Turn off the first peristaltic pump, start the second peristaltic pump, close the second microvalve and the fourth microvalve, open the sixth microvalve, so that the etchant B circulates in the etching liquid channel; Step S5: Remove the microfluidic etched chip, clean the glass substrate, and dry it with nitrogen gas to obtain a glass substrate with glass microchannels formed.

[0016] A microfluidic-assisted wet etching method for glass microchannels, applied to the aforementioned microfluidic-assisted wet etching apparatus for glass microchannels, comprises the following steps: Step S1: Pretreatment of glass substrate: Clean and dry the glass substrate. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate, and laser processing forms pre-etched microchannels on the glass substrate; Step S3, Microfluidic etching chip fabrication: The glass substrate and the flow channel substrate are bonded together to obtain the microfluidic etching chip; Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etchant A to the first storage container, add etchant B to the second storage container, add cleaning and protective agent to the third storage container, start the ultrasonic temperature-controlled water bath device, and place the microfluidic etching chip in the ultrasonic temperature-controlled water bath device. Step S42, Glass microchannel cleaning mode: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, open the seventh microvalve and the fifth microvalve, so that the cleaning protectant enters the etching liquid channel and cleans the pre-etched microchannel; Step S43, Glass microchannel etching mode a: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, close the seventh microvalve, open the first microvalve and the fifth microvalve, so that the cleaning and protective agent in the etching liquid channel is replaced with etchant A, then turn off the second peristaltic pump, close the first microvalve and the fifth microvalve, open the third microvalve, so that etchant A circulates in the etching liquid channel; Step S44, Glass microchannel protection mode a: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, close the third microvalve, and open the fifth microvalve and the seventh microvalve, so that the etchant A in the etching liquid channel is replaced with the cleaning and protective agent; Step S45, Glass microchannel protection mode b: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, close the fifth microvalve and the seventh microvalve, and open the fourth microvalve and the second microvalve, so that the cleaning protectant in the etching liquid channel is replaced with etching agent B; Step S46, Glass microchannel etching mode b: Turn off the first peristaltic pump, start the second peristaltic pump, close the fourth microvalve and the second microvalve, open the sixth microvalve, so that the etchant B can circulate in the etching liquid channel; Step S5: Remove the microfluidic etched chip, clean the glass substrate, and dry it with nitrogen gas to obtain a glass substrate with glass microchannels formed.

[0017] Optionally, the ultrasonic power of the ultrasonic temperature-controlled water bath device is 35W-70W, the ultrasonic frequency is 5Hz-25Hz, the ultrasonic amplitude is 0.6mm-1.8mm, and the water bath temperature is 40℃-80℃.

[0018] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: 1. By setting up a microfluidic etching chip, microfluidic technology is applied to the wet etching process of glass channels. This restricts the flow path of the etchant, allowing the etchant to act on the glass substrate only in the etching solution channel. Compared with the existing method of directly immersing the glass substrate in the etching solution, this method has the advantages of using less etchant and improving the etching rate. In conjunction with the ultrasonic temperature-controlled water bath device, the microfluidic chip can be supplemented with ultrasonic water bath and temperature control during the etching process to achieve etching at a specified temperature. At the same time, the use of ultrasound helps to remove the etching reactants, ensuring the rate of the wet chemical etching reaction. When the concentration of the etchant needs to be changed during the etching process (to adapt to the requirements of the etching process and different etching stages), only the corresponding peristaltic pump and valve need to be turned on, thereby replacing the etchant in the etching fluid channel. Through the coupling effect of multiple fields such as the flow field, temperature field, concentration field and ultrasonic field of the etching process, the flow path of the etchant can be effectively restricted, the etchant dosage can be reduced, the material transport can be promoted, and the etching rate, anisotropy and morphology quality can be improved, thus achieving high-precision and high-efficiency etching. Compared with the existing method of using a single etching solution (which cannot adjust the component concentration of the etching solution according to the etching stage and morphology, and has low solution flow and mass transfer efficiency in etching microchannels), microfluidic technology restricts the flow path of the etchant and adjusts the component concentration of the etching solution in real time through the combined control of peristaltic pumps and microvalves, which has the characteristics of good controllability and high control precision.

[0019] 2. In microfluidic etching chips, laser-modified pre-etching forms pre-etched microchannels (the prototype of glass microchannels) in a glass substrate, effectively assisting in the wet etching process of various glass microchannel structures. The etchant is responsible for etching to form the final morphology of the microchannel. Compared with simply using an etchant for morphology control, it improves the processing efficiency and anisotropy of glass microchannels, giving them higher processing precision and enabling the fabrication of more complex glass microchannels, thus having the advantage of wide applicability.

[0020] 3. The flow rate of the etchant can be adjusted by the first and second peristaltic pumps, and the flow rate can be controlled according to the composition and concentration of the etchant to meet the requirements of fluidity and mass transfer efficiency in the etching process. With the help of multiple micro-valves to automatically adjust the etching process, and with the help of microfluidic technology, the amount of etchant used can be greatly reduced, the safety of the etching process can be improved, and the amount of etchant contamination can be reduced. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a microfluidic-assisted wet etching apparatus for glass microchannels according to an embodiment of the present invention.

[0022] Figure 2 This is a schematic diagram of the structure of a microfluidic etching chip in a microfluidic-assisted glass microchannel wet etching process according to an embodiment of the present invention, wherein the pre-etched microchannel is a 3D microchannel (glass spiral microchannel).

[0023] Figure 3 This is a schematic diagram of the structure of a microfluidic etching chip in a microfluidic-assisted glass microchannel wet etching process according to an embodiment of the present invention, wherein the pre-etched microchannels are glass vias arranged in an array.

[0024] Figure 4 This is a schematic diagram of the etching process of a microfluidic-assisted wet etching method for glass microchannels according to an embodiment of the present invention (the pre-etched microchannels are glass vias arranged in an array). Figure 4 (A) in the diagram is a schematic diagram of ultrafast laser modification. Figure 4 (B) in the diagram is a schematic diagram of the formation of pre-etched microchannels on a glass substrate through ultrafast laser modification. Figure 4 (C) in the diagram is a schematic diagram of the fabrication of a microfluidic chip and its application in wet etching of glass microchannels. Figure 4 (D) in the figure is a schematic diagram of a glass via array formed by wet etching of glass microchannels.

[0025] Figure 5 This is a schematic diagram of the etching process of a microfluidic-assisted wet etching method for glass microchannels according to an embodiment of the present invention (the pre-etched microchannel is a glass microgroove). Figure 5 (A) in the diagram is a schematic diagram of ultrafast laser modification. Figure 5 (B) is a schematic diagram of the formation of pre-etched microchannels on a glass substrate through ultrafast laser modification. Figure 5 (C) in the diagram is a schematic diagram of the fabrication of a microfluidic chip and its application in wet etching of glass microchannels. Figure 5 (D) in the figure is a schematic diagram of glass microgrooves formed by wet etching of glass microchannels.

[0026] Figure 6This is a schematic diagram of the etching process of a microfluidic-assisted wet etching method for glass microchannels according to an embodiment of the present invention (the pre-etched microchannel is a glass spiral microchannel). Figure 6 (A) in the diagram is a schematic diagram of ultrafast laser modification. Figure 6 (B) is a schematic diagram of the formation of pre-etched microchannels on a glass substrate through ultrafast laser modification. Figure 6 (C) in the diagram is a schematic diagram of the fabrication of a microfluidic chip and its application in wet etching of glass microchannels. Figure 6 (D) in the figure is a schematic diagram of the formation of 3D microchannels (glass spiral microchannels) by wet etching of glass microchannels.

[0027] The components include: a first storage container 1, a second storage container 2, a first peristaltic pump 3, a second peristaltic pump 4, a microfluidic etched chip 5, a glass substrate 51, a pre-etched microchannel 511, a glass through-hole 512, a flow channel substrate 52, a liquid inlet 521, a liquid outlet 522, an auxiliary flow channel 523, an upper flow channel substrate 524, a dispersing microchannel 5241, a lower flow channel substrate 525, a converging microchannel 5251, an ultrasonic temperature-controlled water bath device 6, a recovery container 7, a first liquid inlet main pipe 8, a first microvalve 81, and a... 9. First inlet branch pipe, 10. First outlet branch pipe, 11. First recovery pipe, 11. Second micro valve, 111. First circulation pipe, 12. Third micro valve, 121. Second inlet main pipe, 13. Fourth micro valve, 131. Second inlet branch pipe, 14. Second outlet branch pipe, 15. Second recovery pipe, 16. Fifth micro valve, 161. Second circulation pipe, 17. Sixth micro valve, 171. Third storage container, 18. Third inlet main pipe, 19. Seventh micro valve, 191. Micro mixer, 20. Microscopic CCD camera, 21. Industrial control computer, 22. Detailed Implementation

[0028] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0029] In the description of this invention, it should be understood that the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, features defined with "first" and "second" may explicitly or implicitly include one or more of these features, used to distinguish and describe features, without any order or emphasis.

[0030] like Figure 1 As shown, a microfluidic-assisted wet etching apparatus for glass microchannels includes a first storage container 1, a second storage container 2, a first peristaltic pump 3, a second peristaltic pump 4, a microfluidic etching chip 5, an ultrasonic temperature-controlled water bath device 6, and a recovery container 7. The first storage container 1 and the second storage container 2 are used to store etching agents with different compositions and concentrations. The microfluidic etching chip 5 is disposed in the ultrasonic temperature-controlled water bath device 6. The microfluidic etching chip 5 includes a bonded glass substrate 51 and a channel substrate 52. The glass substrate 51 is laser-pre-etched to form a pre-etched microchannel 511. The channel substrate 52 is provided with an inlet 521 and an outlet 522. The inlet end of the pre-etched microchannel 511 is connected to the inlet 521, and the outlet end of the pre-etched microchannel 511 is connected to the outlet 522 to form an etching liquid channel. The first storage container 1 is connected to the first input end of the first peristaltic pump 3 via the first inlet main pipe 8. The first inlet main pipe 8 is provided with a first micro valve 81. The first output end of the first peristaltic pump 8 is connected to the inlet 521 via the first inlet branch pipe 9. The outlet 522 is connected to the second input end of the first peristaltic pump 3 via the first outlet branch pipe 10. The second output end of the first peristaltic pump 3 is connected to the recovery container 7 via the first recovery liquid pipe 11. The first recovery liquid pipe 11 is provided with a second micro valve 111. A first circulation pipe 12 is connected between the second output end of the first peristaltic pump 3 and the second micro valve 111, and between the first micro valve 81 and the first input end of the first peristaltic pump 3. The first circulation pipe 12 is provided with a third micro valve 121. The second storage container 2 is connected to the third input end of the second peristaltic pump 4 via the second inlet main pipe 13. The second inlet main pipe 13 is equipped with a fourth micro valve 131. The third output end of the second peristaltic pump 4 is connected to the inlet port 521 via the second inlet branch pipe 14. The outlet port 522 is connected to the fourth input end of the second peristaltic pump 4 via the second outlet branch pipe 15. The fourth output end of the second peristaltic pump 4 is connected to the recovery container 7 via the second recovery liquid pipe 16. The second recovery liquid pipe 16 is equipped with a fifth micro valve 161. A second circulation pipe 17 is connected between the fourth output end of the second peristaltic pump 4 and the fifth micro valve 161, and between the fourth micro valve 131 and the third input end of the second peristaltic pump 4. The second circulation pipe 17 is equipped with a sixth micro valve 171.

[0031] This invention, based on the premise of forming microchannel deformation regions with specific morphologies on a glass substrate 51 using laser technology, prepares a microfluidic etching chip 5 for wet etching. By restricting the flow path of the etching solution and reducing the amount of etchant used through microfluidic technology, and employing a microfluidic-assisted glass microchannel wet etching processing device, the component concentration of the etching solution, the flow rate of the microchannel, the temperature, and the ultrasonic vibration parameters can be adjusted in real time according to the etching process requirements. Ultrasonic water baths and temperature control are applied to the etching process to promote material transport, improve etching efficiency, anisotropy, and morphology quality, thereby precisely controlling the processing flow, realizing the preparation of various glass microchannels, and achieving high-quality etching processing of glass microchannels. It has the advantages of high etching accuracy and high efficiency.

[0032] Specifically, the steps for performing glass microchannel wet etching using the microfluidic-assisted glass microchannel wet etching apparatus of the present invention are as follows: Step S1, Pretreatment of glass substrate 51: The glass substrate 51 is ultrasonically cleaned with water bath and dried with nitrogen. Step S2, Ultrafast Laser Modification: According to the specific target glass microchannel requirements, the working parameters of the laser are set, and the glass substrate 51 is laser pre-etched. The laser processing forms a pre-etched microchannel 511 on the glass substrate 51. The glass substrate 51 undergoes an induced phase transition under the action of the laser, that is, the chemical composition of the material changes. The laser-modified processing area on the glass substrate 51 forms a microchannel prototype. Step S3, Microfluidic etching chip 5 fabrication: The glass substrate 51 and the flow channel substrate 52 are bonded together to obtain the microfluidic etching chip; Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etchant A to the first storage container 1 and etchant B to the second storage container 2. Start the ultrasonic temperature-controlled water bath device 6 and place the microfluidic etching chip 5 inside the ultrasonic temperature-controlled water bath device 6. Step S42, Glass microchannel etching mode a: Start the first peristaltic pump 3, turn off the second peristaltic pump 4, open the first micro valve 81 to fill the etching liquid channel with etchant A; close the first micro valve 81 and open the third micro valve 121 to allow etchant A to circulate within the etching liquid channel. Step S43, Etching agent switching mode: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the third micro valve 121, and open the second micro valve 111 and the fourth micro valve 131 to replace etchant A in the etching liquid flow channel with etchant B; Step S44, Glass microchannel etching mode b: Turn off the first peristaltic pump 3, start the second peristaltic pump 4, close the second microvalve 111 and the fourth microvalve 131, open the sixth microvalve 171, so that the etchant B circulates in the etching liquid channel; Step S5: Remove the microfluidic etched chip 5, clean the glass substrate 51, and dry it with nitrogen to obtain a glass substrate 51 with glass microchannels formed.

[0033] It should be noted that during the aforementioned wet etching process of glass microchannels, all microvalves that were not mentioned as being open were in the closed state.

[0034] Specifically, the first storage container 1 is used to store etchant A, and the second storage container 2 is used to store etchant B. The composition and concentration of etchant A are different from those of etchant B. The glass substrate 51, after laser modification and pre-etching, can be selectively etched in etchant A and etchant B to form corresponding etched structures. Further explanation: because etchant A and etchant B have different compositions and concentrations, they exhibit different characteristics in terms of etching rate and etching quality. The purpose of using two etchants is to meet the different etching rate and etching quality requirements at different stages of the etching process, thus employing different etchants in the overall etching process to satisfy the etching rate and etching quality requirements of the microchannel.

[0035] For example, when the structural characteristics of a glass microchannel require the overall processing to be coarse etching followed by fine etching to achieve high surface quality, etchant A (fast etching rate, low surface quality) and etchant B (slow etching rate, high surface quality) can be prepared for coarse etching. Through staged etching—stage 1 (glass microchannel etching mode a): coarse etching, etchant A self-circulating; stage 2 (etchant switching mode): etchant A is replaced by etchant B; stage 3 (glass microchannel etching mode b): fine etching, etchant B self-circulating—the processing requirements of different glass microchannels can be met by replacing the etchant. The microfluidic-assisted wet etching apparatus for glass microchannels of this invention has the following characteristics: 1. By setting the microfluidic etching chip 5, microfluidic technology is applied to the wet etching process of the glass channel, which can restrict the flow path of the etchant, so that the etchant only acts on the glass substrate 51 in the etching liquid channel. Compared with the existing method of directly immersing the glass substrate 51 in the etching solution, it has the advantages of less etchant and improved etching rate. With the ultrasonic temperature-controlled water bath device 6, the microfluidic etching chip 5 can be supplemented with ultrasonic water bath and temperature control during the etching process to achieve etching at a specified temperature. At the same time, the use of ultrasound helps to remove the etching reactants and ensure the rate of wet chemical etching reaction. When the concentration of the etchant needs to be changed during the etching process (to adapt to the requirements of the etching process and different etching stages), it is only necessary to activate the corresponding peristaltic pump and valves to replace the etchant in the etching fluid channel. Through the coupling effect of multiple fields such as the flow field, temperature field, concentration field, and ultrasonic field during the etching process, the flow path of the etchant can be effectively restricted, the etchant dosage can be reduced, material transport can be promoted, and the etching rate, anisotropy, and morphology quality can be improved, achieving high-precision and high-efficiency etching. Compared with the existing method of using a single etching solution (which cannot adjust the component concentration of the etching solution according to the etching stage and morphology, and has low solution flow and mass transfer efficiency in the etching microchannels), microfluidic technology restricts the flow path of the etchant and adjusts the component concentration of the etching solution in real time through the combined control of peristaltic pumps and microvalves, which has the characteristics of good controllability and high control precision.

[0036] 2. In the microfluidic etching chip 5, the pre-etched microchannel 511 (the prototype of the glass microchannel) is formed in the glass substrate 51 by laser modification pre-etching. This effectively assists in completing the wet etching process of various glass microchannel structures. The etchant is responsible for etching to form the final morphology of the microchannel. Compared with simply using the etchant for morphology control, this improves the processing efficiency and anisotropy of the glass microchannel, giving the glass microchannel higher processing accuracy and enabling the fabrication of more complex glass microchannels. It has the advantage of a wide range of applications.

[0037] 3. The flow rate of the etchant can be adjusted by the first peristaltic pump 3 and the second peristaltic pump 4, and the flow rate can be controlled according to the composition and concentration of the etchant to meet the requirements of the etching process for fluidity and mass transfer efficiency. With the help of multiple micro-valves to automatically adjust the etching process, and with the help of microfluidic technology, the amount of etchant used can be greatly reduced, the safety of the etching process can be improved, and the amount of etchant contamination can be reduced.

[0038] The microfluidic-assisted wet etching apparatus for glass microchannels of the present invention has the advantages of good controllability of the etching process, real-time adjustment of etchant concentration, low etchant consumption, high mass transfer efficiency, high etching rate, good anisotropy and morphological quality of the etched glass microchannels, and high etching precision. It solves the technical problems of existing wet etching apparatuses, such as inability to adjust the concentration of etching solution in real time, poor solution flow, low mass transfer efficiency, low etching rate, large etching waste liquid, large etching sidewall inclination angle, and poor consistency.

[0039] To further explain, the liquid inlet 521 of the flow channel substrate 52, the pre-etched microchannel 511, and the liquid outlet 522 of the flow channel substrate 52 are connected to form the etching liquid flow channel.

[0040] It should be noted that the first input terminal and the first output terminal of the first peristaltic pump 3 are connected, and the liquid entering from the first input terminal of the first peristaltic pump 3 will be output from the first output terminal. The second input terminal and the second output terminal of the first peristaltic pump 3 are connected, and the liquid entering from the second input terminal of the first peristaltic pump 3 will be output from the second output terminal. The third input terminal and the third output terminal of the second peristaltic pump 4 are connected, and the liquid entering from the fourth input terminal of the second peristaltic pump 4 will be output from the fourth output terminal.

[0041] In one embodiment of the present invention, the microfluidic-assisted glass microchannel wet etching apparatus further includes a third storage container 18 and a third liquid inlet pipe 19. The third storage container 18 is used to store a cleaning and protective agent. The input end of the third liquid inlet pipe 19 is disposed in the third storage container 18. The output end of the third liquid inlet pipe 19 is connected to the first liquid inlet pipe 8, and the output end of the third liquid inlet pipe 19 is located between the first micro valve 81 and the first input end of the first peristaltic pump 3. The third liquid inlet main pipe 19 is equipped with a seventh micro valve 191.

[0042] Since the present invention uses laser pre-etching to pre-treat the glass substrate 51, the glass material is prone to generating many plasma micro-explosions after laser ablation. The laser-modified area will be wrapped by these plasma micro-explosions, thus hindering the entry of the etchant. In addition, since the components and concentrations of etchant A and etchant B are different, that is, etchant A and etchant B have different performance in etching rate and etching quality, when the etchant is switched, if etchant A and etchant B are present in the etching liquid channel at the same time, etchant A and etchant B will act on the glass substrate 51 in the etching liquid channel at the same time. At this time, the etching reaction process will be disrupted, affecting the etching quality of the glass microchannel. For example, the surface roughness of the glass microchannel may be poor.

[0043] By setting up the third storage container 18, the third liquid inlet pipe 19, and the seventh microvalve 191, the third storage container 18 is used to store the cleaning and protective agent. Before the etching process begins, the self-circulation stage of the cleaning and protective agent can be increased through the third storage container 18, the third liquid inlet pipe 19, and the seventh microvalve 191. When switching etchants, the replacement of etchant A and etchant B can be changed to an intermediate replacement of etchant and cleaning and protective agent. Since the cleaning and protective agent does not react with the glass material, after the self-circulation stage of etchant A is completed, etchant A is first replaced with the cleaning and protective agent. After the cleaning and protective agent completely fills the etching fluid channel, the cleaning and protective agent is then replaced with etchant B to enter the next etching stage. By allowing the cleaning and protective agent to enter the etching fluid channel and clean the pre-etched microchannel 511 before the etching process begins, the unobstructed flow of the etching fluid channel can be ensured, guaranteeing material transport and etching efficiency. By employing an intermediate replacement mode between the etchant and the cleaning and protective agent, the mixing of etchants of different concentrations and compositions within the etching fluid channel can be avoided, thus preventing interference with etching quality. This effectively improves etching precision, resulting in smooth inner walls (i.e., low surface roughness) and the absence of structural defects such as pores in the glass microchannels. The etching process, which adds a self-circulation stage for the cleaning and protective agent and changes the replacement of etchant A and etchant B to an intermediate replacement mode between the etchant and the cleaning and protective agent, is as follows: Step S1, Pretreatment of glass substrate 51: The glass substrate 51 is ultrasonically cleaned with water bath and dried with nitrogen. Step S2, Ultrafast Laser Modification: According to the specific target glass microchannel requirements, the working parameters of the laser are set, and the glass substrate 51 is laser pre-etched. The laser processing forms a pre-etched microchannel 511 on the glass substrate 51. The glass substrate 51 undergoes an induced phase transition under the action of the laser, that is, the chemical composition of the material changes. The laser-modified processing area on the glass substrate 51 forms a microchannel prototype. Step S3: Fabrication of microfluidic etched chip: The glass substrate 51 and the flow channel substrate 52 are bonded together to obtain the microfluidic etched chip 5; Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etchant A to the first storage container 1, add etchant B to the second storage container 2, add cleaning and protective agent to the third storage container 18, start the ultrasonic temperature-controlled water bath device 6, and place the microfluidic etching chip 5 into the ultrasonic temperature-controlled water bath device 6. Step S42, Glass microchannel cleaning mode: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, open the seventh microvalve 191 and the fifth microvalve 161, so that the cleaning protectant enters the etching liquid channel and cleans the pre-etched microchannel 511; Step S43, Glass microchannel etching mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the seventh microvalve 191, open the first microvalve 81 and the fifth microvalve 161, so that the cleaning and protective agent in the etching liquid channel is replaced with etchant A, then turn off the second peristaltic pump 4, close the first microvalve 81 and the fifth microvalve 161, open the third microvalve 121, so that etchant A circulates in the etching liquid channel; Step S44, Glass microchannel protection mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the third microvalve 121, and open the fifth microvalve 161 and the seventh microvalve 191, so that the etchant A in the etching liquid channel is replaced with the cleaning and protection agent; Step S45, Glass microchannel protection mode b: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the fifth microvalve 161 and the seventh microvalve 191, and open the fourth microvalve 131 and the second microvalve 111, so that the cleaning protectant in the etching liquid channel is replaced with etching agent B; Step S46, Glass microchannel etching mode b: Turn off the first peristaltic pump 3, start the second peristaltic pump 4, close the fourth microvalve 131 and the second microvalve 111, open the sixth microvalve 171, so that the etchant B can circulate in the etching liquid channel. Step S5: Remove the microfluidic etched chip 5, clean the glass substrate 51, and dry it with nitrogen to obtain a glass substrate 51 with glass microchannels formed.

[0044] like Figure 2 As shown, in one embodiment of the present invention, the pre-etched microchannel 511 of the glass substrate 51 is a glass microgroove or a 3D microchannel, and the flow channel substrate 52 is disposed on the upper end surface of the glass substrate 51. The flow channel substrate 52 is also provided with an auxiliary flow channel 523, and the auxiliary flow channel 523 is respectively connected between the liquid inlet 521 and the liquid inlet end of the pre-etched microchannel 511 and between the liquid outlet end of the pre-etched microchannel 511 and the liquid outlet 522.

[0045] When the pre-etched microchannel 511 of the glass substrate 51 is a glass microgroove or a 3D microchannel, the glass substrate 51 (target substrate) is used as the lower substrate, and the flow channel substrate 52 is disposed on the upper surface of the glass substrate 51. The fabrication of the microfluidic etched chip 5 is completed through the bonding process of the upper and lower substrates. The pre-etched microchannel 511 of the glass substrate 51 is the main microchannel of the microfluidic etched chip 5. At this time, the flow channel substrate 52 is provided with the liquid inlet 521. The outlet 522 and the auxiliary flow channel 523 are connected in sequence to form the etching liquid flow channel, which consists of the inlet 521, one of the auxiliary flow channels 523, the pre-etched microchannel 511, the other auxiliary flow channel 523, and the outlet 522. The design of the etching liquid flow channel can effectively limit the flow path of the etching liquid, reduce the amount of etchant used, promote material transport, and thus improve the etching rate, anisotropy and morphology quality, achieving high-precision and high-efficiency etching.

[0046] like Figure 3 As shown, in another embodiment of the present invention, the pre-etched microchannels 511 of the glass substrate 51 include a plurality of arrayed glass vias 512, the flow channel substrate 52 includes an upper flow channel substrate 524 and a lower flow channel substrate 525, the upper flow channel substrate 524 is disposed on the upper end surface of the glass substrate 51, the liquid inlet 521 is disposed on the upper flow channel substrate 524, the lower flow channel substrate 525 is disposed on the lower end surface of the glass substrate 51, and the liquid outlet 522 is disposed on the lower flow channel substrate 525; The upper flow channel substrate 524 is provided with a dispersion microchannel 5241, the liquid inlet end of the dispersion microchannel 5241 is connected to the liquid inlet 521, and the liquid outlet end of the dispersion microchannel 5241 is provided in a one-to-one correspondence with the liquid inlet end of the glass through hole 512. The lower flow channel substrate 525 is provided with a converging microchannel 5251, the liquid inlet end of the converging microchannel 5251 is provided in a one-to-one correspondence with the liquid outlet end of the glass through hole 512, and the liquid outlet end of the converging microchannel 5251 is connected to the liquid outlet 522.

[0047] When the pre-etched microchannels 511 of the glass substrate 51 are a glass via array, the glass substrate 51 (target substrate) is used as the intermediate substrate. The upper flow channel substrate 524 is disposed on the upper end face of the glass substrate 51, and the lower flow channel substrate 525 is disposed on the lower end face of the glass substrate 51. The liquid inlet 521 is provided on the upper flow channel substrate 524, and the liquid outlet 522 is provided on the lower flow channel substrate 525. The dispersing microchannels 5241 are provided on the upper flow channel substrate 524, and the converging microchannels are provided on the lower flow channel substrate 525. The upper flow channel substrate 524, the glass substrate 51, and the lower flow channel substrate 525 are bonded to form a three-layer microfluidic etching chip 5. The liquid inlet 521, the dispersing microchannel 5241, the glass through-hole 512, the converging microchannel 5251, and the liquid outlet 522 are sequentially connected to form the etching liquid flow channel. The design of the etching liquid flow channel can effectively limit the flow path of the etching liquid, reduce the amount of etchant used, promote material transport, and thus improve the etching rate, anisotropy, and morphology quality, achieving high-precision and high-efficiency etching.

[0048] Specifically, the dispersing microchannel 5241 has one inlet end and multiple outlet ends. The multiple outlet ends of the dispersing microchannel 5241 are configured one-to-one with the inlet ends of the multiple glass through holes 512. Similarly, the converging microchannel 5251 has multiple inlet ends and one outlet end. The multiple inlet ends of the converging microchannel 5251 are configured one-to-one with the outlet ends of the multiple glass through holes 512. This enables the etching solution to be diverted to each of the glass through holes 512 through the dispersing microchannel 5241, allowing the etching solution to be diverted to each of the glass through holes 512 and used to etch multiple pre-etched glass through holes 512. It also enables the etching solution to be re-converged from the multiple glass through holes 512 back to the outlet 522, thereby realizing the recovery or circulation of the etching solution.

[0049] Furthermore, when the pre-etched microchannels 511 of the glass substrate 51 are an array of multiple glass microgrooves, the auxiliary flow channel 523 connecting the liquid inlet 521 and the liquid inlet end of the pre-etched microchannel 511 can also be configured as a dispersing microflow channel 5241 to achieve communication between the liquid inlet 521 and the liquid inlet ends of the multiple glass microgrooves. The auxiliary flow channel 523 connecting the liquid outlet end of the pre-etched microchannel 511 and the liquid outlet 522 can also be configured as a converging microflow channel 5251 to achieve communication between the liquid outlet 522 and the liquid outlet ends of the multiple glass microgrooves.

[0050] In this invention, the microfluidic etching chip 5 structure is designed according to the design of the target microchannel, which can assist in the wet etching process of various glass microchannel structures.

[0051] Preferably, the system further includes a micro mixer 20, which has two inlet ends. The first inlet branch pipe 9 is connected to one of the inlet ends of the micro mixer 20, and the second inlet branch pipe 14 is connected to the other inlet end of the micro mixer 20. The outlet end of the micro mixer 20 is connected to the inlet port 521.

[0052] The first peristaltic pump 3 and the second peristaltic pump 4 can accurately and quantitatively deliver etchant A and etchant B to the micro mixer 20. However, since the solution output by the peristaltic pump is not uniform and stable enough, in order to achieve a better etching effect, the micro mixer 20 is set up so that the solution output from the micro mixer 20 is more uniform and stable, without turbulence or air bubbles, thereby ensuring etching accuracy.

[0053] Preferably, it also includes a micro CCD camera 21, which is disposed on the outside of the ultrasonic temperature-controlled water bath device 6, with the imaging end of the micro CCD camera 21 facing the ultrasonic temperature-controlled water bath device 6, and the position of the micro CCD camera 21 aligned with the microfluidic etching chip 5. The microfluidic etching chip 5 is located at the center of the ultrasonic temperature-controlled water bath device 6.

[0054] By setting up the micro-CCD camera 21, operators can observe and monitor the etching process. Positioning the microfluidic etching chip 5 at the center of the ultrasonic temperature-controlled water bath 6 ensures that the ultrasonic waves and heating temperature are evenly distributed and act on the etching solution within the etching solution channel. This results in a uniform concentration of the etching solution and promotes material transport. The microfluidic etching chip 5 receives uniform ultrasonic treatment and temperature control, improving etching accuracy.

[0055] Specifically, the ultrasonic temperature-controlled water bath device 6 can be an ultrasonic constant temperature water bath box, and the box wall of the ultrasonic temperature-controlled water bath device 6 is made of transparent material to facilitate the microscopic CCD camera 21 to take pictures.

[0056] To further explain, it also includes an industrial control computer 22, and the first peristaltic pump 3, the second peristaltic pump 4, the ultrasonic temperature-controlled water bath device 6, the first micro valve 81, the second micro valve 111, the third micro valve 121, the fourth micro valve 131, the fifth micro valve 161, the sixth micro valve 171 and the seventh micro valve 191 are respectively connected to the industrial control computer 22.

[0057] The industrial control computer 22 is connected to the first peristaltic pump 3, the second peristaltic pump 4, the ultrasonic temperature-controlled water bath device 6, the first microvalve 81, the second microvalve 111, the third microvalve 121, the fourth microvalve 131, the fifth microvalve 161, the sixth microvalve 171, and the seventh microvalve 191. This allows for the automatic adjustment of the etching solution switching mode according to the glass microchannel in real time. Only the etching agent and the prepared microfluidic etching chip 5 need to be prepared in advance; the processing of any glass microchannel can be completed automatically, exhibiting high control precision and automation, reducing the uncertainty and safety risks associated with repeated manual operations.

[0058] Specifically, the industrial control computer 22 is responsible for controlling the operating modes of the first peristaltic pump 3 and the second peristaltic pump 4, so that the entire etching process does not require manual replacement of the etching agent, and the experimenter can monitor it through the micro-CCD camera 21. When it is necessary to switch the processing mode, the industrial control computer 22 can control the start and stop of the first peristaltic pump 3 and the second peristaltic pump 4, as well as the start and stop of each micro-valve, to realize the etching time, peristaltic pump operating mode, ultrasonic water bath and temperature control at each stage. Before the etching begins, the control parameters are determined according to the specific structure of the glass microchannel and input into the industrial control computer 22.

[0059] Specifically, based on different microchannel types and specific etching processes, the industrial control computer 22 outputs flow rate parameters. The industrial control computer 22 precisely controls the operating mode, operating time, and mass flow rate of the first peristaltic pump 3 and the second peristaltic pump 4 to meet the real-time adjustment of the etching mode according to etching requirements. This allows for two main benefits: firstly, automatic replacement of the etchant as the etching process progresses; and secondly, the use of microvalves to achieve self-circulation of the etchant during the etching process, improving the fluidity of the etching solution. Combined with an ultrasonic water bath, this ensures uniform etching solution concentration, allowing reaction byproducts to be discharged promptly and preventing localized accumulation that weakens etchant participation, thereby improving mass transfer efficiency. Furthermore, the preferred flow rates of the first peristaltic pump 3 and the second peristaltic pump 4 are 10 μL / min to 50 μL / min.

[0060] In one embodiment of the present invention, a microfluidic-assisted wet etching method for glass microchannels is applied to the aforementioned microfluidic-assisted wet etching apparatus for glass microchannels. The microfluidic-assisted wet etching method for glass microchannels includes the following steps: Step S1: Pretreatment of glass substrate 51: Clean and dry glass substrate 51. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate 51, and laser processing forms pre-etched microchannels 511 on the glass substrate 51; Step S3, fabrication of microfluidic etched chip 5: The glass substrate 51 and the flow channel substrate 52 are bonded together to obtain the microfluidic etched chip 5; Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etchant A to the first storage container 1 and etchant B to the second storage container 2. Start the ultrasonic temperature-controlled water bath device 6 and place the microfluidic etching chip 5 inside the ultrasonic temperature-controlled water bath device 6. Step S42, Glass microchannel etching mode a: Start the first peristaltic pump 3, turn off the second peristaltic pump 4, open the first micro valve 81 to fill the etching liquid channel with etchant A; close the first micro valve 81 and open the third micro valve 121 to allow etchant A to circulate within the etching liquid channel. Step S43, Etching agent switching mode: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the third micro valve 121, and open the second micro valve 111 and the fourth micro valve 131 to replace etchant A in the etching liquid flow channel with etchant B; Step S44, Glass microchannel etching mode b: Turn off the first peristaltic pump 3, start the second peristaltic pump 4, close the second microvalve 111 and the fourth microvalve 131, open the sixth microvalve 171, so that the etchant B circulates in the etching liquid channel; Step S5: Remove the microfluidic etched chip 5, clean the glass substrate 51, and dry it with nitrogen to obtain a glass substrate 51 with glass microchannels formed.

[0061] The microfluidic-assisted wet etching method for glass microchannels can use different etchants according to etching requirements. It can also achieve automatic switching of etchants by controlling the first peristaltic pump 3 and the second peristaltic pump 4, as well as different microvalve. It can adjust the etchant concentration in real time, resulting in good controllability of the etching process, low etchant consumption, high mass transfer efficiency, high etching rate, good anisotropy and morphological quality of the etched glass microchannels, and high etching precision. It solves the technical problems of existing wet etching devices, such as poor solution flow, low mass transfer efficiency, low etching rate, large etching waste liquid, large etching sidewall inclination angle, and poor consistency, which cannot adjust the concentration of the etching solution in real time.

[0062] To further explain, when the pre-etched microchannels 511 of the glass substrate 51 are glass via arrays, an ultrafast Bessel laser beam is used to form extremely fine pre-etched microchannels 511 and modified regions penetrating the glass substrate 51; when the pre-etched microchannels 511 of the glass substrate 51 are glass microgrooves or 3D microchannels, an ultrafast laser direct writing technology is used to generate modified regions with specific morphologies on the glass substrate 51.

[0063] Furthermore, the auxiliary flow channel 523, the dispersing microflow channel 5241, and the converging microflow channel 5251 can be fabricated on the flow channel substrate 52 by laser drilling.

[0064] In one embodiment of the present invention, a microfluidic-assisted wet etching method for glass microchannels is applied to the aforementioned microfluidic-assisted wet etching apparatus for glass microchannels. The microfluidic-assisted wet etching method for glass microchannels includes the following steps: Step S1: Pretreatment of glass substrate 51: Clean and dry glass substrate 51. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate 51, and laser processing forms pre-etched microchannels 511 on the glass substrate 51; Step S3, fabrication of microfluidic etched chip 5: The glass substrate 51 and the flow channel substrate 52 are bonded together to obtain the microfluidic etched chip 5; Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etchant A to the first storage container 1, add etchant B to the second storage container 2, add cleaning and protective agent to the third storage container 18, start the ultrasonic temperature-controlled water bath device 6, and place the microfluidic etching chip 5 into the ultrasonic temperature-controlled water bath device 6. Step S42, Glass microchannel cleaning mode: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, open the seventh microvalve 191 and the fifth microvalve 161, so that the cleaning protectant enters the etching liquid channel and cleans the pre-etched microchannel 511; Step S43, Glass microchannel etching mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the seventh microvalve 191, open the first microvalve 81 and the fifth microvalve 161, so that the cleaning and protective agent in the etching liquid channel is replaced with etchant A, then turn off the second peristaltic pump 4, close the first microvalve 81 and the fifth microvalve 161, open the third microvalve 121, so that etchant A circulates in the etching liquid channel; Step S44, Glass microchannel protection mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the third microvalve 121, and open the fifth microvalve 161 and the seventh microvalve 191, so that the etchant A in the etching liquid channel is replaced with the cleaning and protection agent; Step S45, Glass microchannel protection mode b: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the fifth microvalve 161 and the seventh microvalve 191, and open the fourth microvalve 131 and the second microvalve 111, so that the cleaning protectant in the etching liquid channel is replaced with etching agent B; Step S46, Glass microchannel etching mode b: Turn off the first peristaltic pump 3, start the second peristaltic pump 4, close the fourth microvalve 131 and the second microvalve 111, open the sixth microvalve 171, so that the etchant B can circulate in the etching liquid channel. Step S5: Remove the microfluidic etched chip 5, clean the glass substrate 51, and dry it with nitrogen to obtain a glass substrate 51 with glass microchannels formed.

[0065] By setting glass microchannel cleaning mode, glass microchannel protection mode a, and glass microchannel protection mode b, a self-circulation stage of the cleaning and protective agent can be added before the etching process begins. This cleans the pre-etched microchannel 511 in the etching liquid channel, removes plasma micro-explosions formed by laser ablation, avoids obstructing the entry of the etchant, ensures the smooth flow of the etching liquid channel, and guarantees the etching effect. Furthermore, during the etching process, the replacement of etchant A and etchant B can be changed to an intermediate replacement of etchant and cleaning and protective agent. This avoids the mixing of etchants of different concentrations and compositions in the etching liquid channel, which would affect the etching quality. This effectively improves the etching precision, making the inner wall of the glass microchannel smooth (i.e., low surface roughness) and free of structural defects such as pores. This solves the existing technical problems of plasma micro-explosions generated by laser ablation obstructing the entry of the etchant, and the impact of different component concentrations of etchant on the etching effect during etchant switching.

[0066] Specifically, the cleaning and protective agent is a neutral water solution. Water does not react with the glass material, which can clean the modified area in the glass substrate 51 after laser ablation. Moreover, the etching effect will not be affected when the etchant and the cleaning and protective agent are replaced in between.

[0067] Preferably, the ultrasonic temperature-controlled water bath device 6 has an ultrasonic power of 35W-70W, an ultrasonic frequency of 5Hz-25Hz, an ultrasonic amplitude of 0.6mm-1.8mm, and a water bath temperature of 40℃-80℃.

[0068] In the ultrasonic temperature-controlled water bath device 6, the simultaneous application of ultrasonic water bath and temperature control can promote material transport, improve etching rate, anisotropy and morphology quality. Temperature control can help meet the processing parameter requirements of glass microchannels. Higher temperatures help improve mass transfer efficiency. Importantly, the method in this invention uses different etchants to participate in the overall etching process in stages. Different etchants have different temperature requirements. Temperature control can also meet the processing parameter requirements of different etchants, further improving etching quality on the basis of improving mass transfer efficiency.

[0069] The following description is based on specific embodiments: Example 1 like Figure 4 As shown, a microfluidic-assisted wet etching method for glass microchannels is applied to the aforementioned microfluidic-assisted wet etching apparatus for glass microchannels. The microfluidic-assisted wet etching method for glass microchannels includes the following steps: Step S1, Pretreatment of glass substrate 51: The glass substrate 51 is ultrasonically cleaned with water bath and dried with nitrogen. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate 51. Laser processing forms pre-etched microchannels on the glass substrate 51. Specifically, the ultrafast Bessel laser beam processing parameters are set as follows: laser wavelength 1030nm, laser average power 10W, laser pulse width 1ps, and laser repetition frequency 100kHz. A glass micro-via array modification region with a aperture of 3μm is processed on the glass substrate 51 with a size of 30*30*0.5mm. Step S3, Microfluidic Etching Chip 5 Fabrication: The glass substrate 51 and the flow channel substrate 52 are bonded together to obtain the microfluidic etching chip 5. Specifically, the pre-etched glass substrate 51 is used as the intermediate substrate, and a glass substrate with a size of 30*30*1mm is used as the upper flow channel substrate 524 and the lower flow channel substrate 525. The aperture of the liquid inlet 521 of the upper flow channel substrate 524 and the aperture of the liquid outlet 522 of the lower flow channel substrate 525 are 5μm, respectively. The aperture of the dispersing microchannel 5241 and the aperture of the converging microchannel 5251 are 3μm, respectively. The three-layer microfluidic etching chip 5 is formed by bonding. Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etching agent A (specifically, 10wt% hydrofluoric acid solution) to the first storage container 1, add etching agent B (specifically, 30wt% KOH solution) to the second storage container 2, add cleaning and protective agent (specifically, neutral water solution) to the third storage container 18, start the ultrasonic temperature-controlled water bath device 6, set the ultrasonic parameters as follows: ultrasonic power 60W, ultrasonic frequency 15Hz, ultrasonic amplitude 1.8mm, water bath temperature 60℃, place the microfluidic etching chip 5 in the center position inside the ultrasonic temperature-controlled water bath device 6, and adjust the flow rate of the first peristaltic pump 3 and the second peristaltic pump 4 to 50μL / min; Step S42, Glass microchannel cleaning mode: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, open the seventh microvalve 191 and the fifth microvalve 161, so that the cleaning protectant enters the etching liquid channel and cleans the pre-etched microchannel 511 for 3 minutes; Step S43, Glass microchannel etching mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the seventh microvalve 191, open the first microvalve 81 and the fifth microvalve 161, so that the cleaning protectant in the etching liquid channel is replaced with etchant A, then turn off the second peristaltic pump 4, close the first microvalve 81 and the fifth microvalve 161, open the third microvalve 121, so that etchant A circulates in the etching liquid channel for 1 hour; Step S44, Glass microchannel protection mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the third microvalve 121, and open the fifth microvalve 161 and the seventh microvalve 191, so that the etchant A in the etching liquid channel is replaced with the cleaning and protection agent; Step S45, Glass microchannel protection mode b: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the fifth microvalve 161 and the seventh microvalve 191, and open the fourth microvalve 131 and the second microvalve 111, so that the cleaning protectant in the etching liquid channel is replaced with etching agent B; Step S46, Glass microchannel etching mode b: Turn off the first peristaltic pump 3, start the second peristaltic pump 4, close the fourth microvalve 131 and the second microvalve 111, open the sixth microvalve 171, and allow the etchant B to circulate in the etching liquid channel for 3 hours. Step S5: Remove the microfluidic etched chip 5, clean the glass substrate 51, and dry it with nitrogen to obtain a glass substrate 51 with glass microchannels formed.

[0070] The glass substrate 51 processed in Example 1 was observed using an optical microscope. The aperture size of the glass microchannel was measured to be approximately 5 μm. (It should be noted that the aperture of the glass microchannel on the surface of the glass substrate 51 was measured. Since the inside of the through hole cannot be measured, the aperture of the surface hole is the same as that of the inside hole.) The taper of the through hole of the glass microchannel was approximately 0.9°. No out-of-roundness phenomenon was observed in the surface hole.

[0071] Example 2 like Figure 5 As shown, a microfluidic-assisted wet etching method for glass microchannels is applied to the aforementioned microfluidic-assisted wet etching apparatus for glass microchannels. The microfluidic-assisted wet etching method for glass microchannels includes the following steps: Step S1, Pretreatment of glass substrate: The glass substrate 51 is ultrasonically cleaned with water bath and dried with nitrogen gas. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate 51. Laser processing forms a pre-etched microchannel 511 on the glass substrate 51. Specifically, the ultrafast laser direct writing processing parameters are set as follows: laser wavelength 1026nm, laser average power 20W, laser pulse width 3ps, and laser repetition frequency 200kHz. A glass microgroove modification area with a groove cross-section of 15*2μm is processed on the glass substrate 51 with a size of 20*10*1mm. The flow rate of the first peristaltic pump 3 and the second peristaltic pump 4 is adjusted to 30μL / min. Step S3: Fabrication of microfluidic etched chip: The glass substrate 51 and the flow channel substrate 52 are bonded together to obtain the microfluidic etched chip 5. Specifically, the pre-etched glass substrate 51 is used as the lower substrate, and a glass substrate with a size of 20*10*1.5mm is used as the flow channel substrate 52 (upper substrate). The inlet 521 and outlet 522 of the flow channel substrate 52 have a pore size of 20μm, and the auxiliary flow channel 523 has a pore size of 10μm. They are bonded together to form a two-layer microfluidic etched chip 5. Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etching agent A (specifically, 20wt% hydrofluoric acid solution) to the first storage container 1, add etching agent B (specifically, 40wt% KOH solution) to the second storage container 2, add cleaning and protective agent (specifically, neutral water solution) to the third storage container 18, start the ultrasonic temperature-controlled water bath device 6, set the ultrasonic parameters as follows: ultrasonic power 70W, ultrasonic frequency 25Hz, ultrasonic amplitude 1.8mm, water bath temperature 70℃, and place the microfluidic etching chip 5 in the center position inside the ultrasonic temperature-controlled water bath device 6; Step S42, Glass microchannel cleaning mode: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, open the seventh microvalve 191 and the fifth microvalve 161, so that the cleaning protectant enters the etching liquid channel and cleans the pre-etched microchannel 511 for 5 minutes; Step S43, Glass microchannel etching mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the seventh microvalve 191, open the first microvalve 81 and the fifth microvalve 161, so that the cleaning protectant in the etching liquid channel is replaced with etchant A, then turn off the second peristaltic pump 4, close the first microvalve 81 and the fifth microvalve 161, open the third microvalve 121, so that etchant A circulates in the etching liquid channel for 30 minutes; Step S44, Glass microchannel protection mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the third microvalve 121, and open the fifth microvalve 161 and the seventh microvalve 191, so that the etchant A in the etching liquid channel is replaced with the cleaning and protection agent; Step S45, Glass microchannel protection mode b: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the fifth microvalve 161 and the seventh microvalve 191, and open the fourth microvalve 131 and the second microvalve 111, so that the cleaning protectant in the etching liquid channel is replaced with etching agent B; Step S46, Glass microchannel etching mode b: Turn off the first peristaltic pump 3, start the second peristaltic pump 4, close the fourth microvalve 131 and the second microvalve 111, open the sixth microvalve 171, and allow the etchant B to circulate in the etching liquid channel for 1 hour. Step S5: Remove the microfluidic etched chip 5, clean the glass substrate 51, and dry it with nitrogen to obtain a glass substrate 51 with glass microchannels formed.

[0072] The glass substrate 51 processed in Example 2 was observed using an optical microscope. The cross-section of the glass microchannel (micro-groove) was measured to be approximately 30*10μm, and the surface roughness Ra value was maintained within 0.005μm.

[0073] Example 3 like Figure 6 As shown, a microfluidic-assisted wet etching method for glass microchannels is applied to the aforementioned microfluidic-assisted wet etching apparatus for glass microchannels. The microfluidic-assisted wet etching method for glass microchannels includes the following steps: Step S1, Pretreatment of glass substrate 51: The glass substrate 51 is ultrasonically cleaned with water bath and dried with nitrogen. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate 51. Laser processing forms a pre-etched microchannel 511 on the glass substrate 51. Specifically, the ultrafast laser direct writing processing parameters are set as follows: laser wavelength 1026nm, laser average power 15W, laser pulse width 2ps, and laser repetition frequency 50kHz. A glass spiral microchannel modification region with a microchannel length of 800μm and an inner diameter of 5μm is processed inside the glass substrate 51 with a size of 20*20*5mm. Step S3, Microfluidic Etching Chip 5 Fabrication: The glass substrate 51 and the flow channel substrate 52 are bonded together to obtain the microfluidic etching chip 5. Specifically, the pre-etched glass substrate 51 is used as the lower substrate, and a glass substrate with a size of 20*20*2mm is used as the flow channel substrate 52 (upper substrate). The inlet 521 and outlet 522 of the flow channel substrate 52 have a pore size of 10μm, and the auxiliary flow channel 523 has a pore size of 10μm. They are bonded together to form a two-layer microfluidic etching chip 5. Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etching agent A (specifically, 10wt% hydrofluoric acid solution) to the first storage container 1, add etching agent B (specifically, 50wt% KOH solution) to the second storage container 2, add cleaning and protective agent (specifically, neutral water solution) to the third storage container 18, start the ultrasonic temperature-controlled water bath device 6, set the ultrasonic parameters as follows: ultrasonic power 35W, ultrasonic frequency 10Hz, ultrasonic amplitude 1.8mm, water bath temperature 80℃, place the microfluidic etching chip 5 in the center position inside the ultrasonic temperature-controlled water bath device 6, and adjust the flow rate of the first peristaltic pump 3 and the second peristaltic pump 4 to 10μL / min; Step S42, Glass microchannel cleaning mode: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, open the seventh microvalve 191 and the fifth microvalve 161, so that the cleaning protectant enters the etching liquid channel and cleans the pre-etched microchannel 511 for 5 minutes; Step S43, Glass microchannel etching mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the seventh microvalve 191, open the first microvalve 81 and the fifth microvalve 161, so that the cleaning protectant in the etching liquid channel is replaced with etchant A, then turn off the second peristaltic pump 4, close the first microvalve 81 and the fifth microvalve 161, open the third microvalve 121, so that etchant A circulates in the etching liquid channel for 15 minutes; Step S44, Glass microchannel protection mode a: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the third microvalve 121, and open the fifth microvalve 161 and the seventh microvalve 191, so that the etchant A in the etching liquid channel is replaced with the cleaning and protection agent; Step S45, Glass microchannel protection mode b: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the fifth microvalve 161 and the seventh microvalve 191, and open the fourth microvalve 131 and the second microvalve 111, so that the cleaning protectant in the etching liquid channel is replaced with etching agent B; Step S46, Glass microchannel etching mode b: Turn off the first peristaltic pump 3, start the second peristaltic pump 4, close the fourth microvalve 131 and the second microvalve 111, open the sixth microvalve 171, and allow the etchant B to circulate in the etching liquid channel for 5 hours. Step S5: Remove the microfluidic etched chip 5, clean the glass substrate 51, and dry it with nitrogen to obtain a glass substrate 51 with glass microchannels formed.

[0074] The glass substrate 51 processed in Example 3 was observed using an optical microscope. The inner diameter of the glass microchannel was measured to be approximately 10 μm, and the surface roughness Ra value was maintained within 0.002 μm.

[0075] Example 4 A microfluidic-assisted wet etching method for glass microchannels, applied to the aforementioned microfluidic-assisted wet etching apparatus for glass microchannels, comprises the following steps: Step S1, Pretreatment of glass substrate 51: The glass substrate 51 is ultrasonically cleaned with water bath and dried with nitrogen. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate 51. Laser processing forms a pre-etched microchannel 511 on the glass substrate 51. Specifically, the ultrafast laser direct writing processing parameters are set as follows: laser wavelength 1026nm, laser average power 15W, laser pulse width 2ps, and laser repetition frequency 50kHz. A glass spiral microchannel modification region with a microchannel length of 800μm and an inner diameter of 5μm is processed inside the glass substrate 51 with a size of 20*20*5mm. Step S3, Microfluidic Etching Chip 5 Fabrication: The glass substrate 51 and the flow channel substrate 52 are bonded together to obtain the microfluidic etching chip 5. Specifically, the pre-etched glass substrate 51 is used as the lower substrate, and a glass substrate with a size of 20*20*2mm is used as the flow channel substrate 52 (upper substrate). The inlet 521 and outlet 522 of the flow channel substrate 52 have a pore size of 10μm, and the auxiliary flow channel 523 has a pore size of 10μm. They are bonded together to form a two-layer microfluidic etching chip 5. Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etching agent A (specifically, a 10wt% hydrofluoric acid solution) to the first storage container 1, and add etching agent B (specifically, a 50wt% KOH solution) to the second storage container 2. Start the ultrasonic temperature-controlled water bath device 6, and set the ultrasonic parameters as follows: ultrasonic power 35W, ultrasonic frequency 10Hz, ultrasonic amplitude 1.8mm, and water bath temperature 80℃. Place the microfluidic etching chip 5 in the center position inside the ultrasonic temperature-controlled water bath device 6, and adjust the flow rate of the first peristaltic pump 3 and the second peristaltic pump 4 to 10μL / min. Step S42, Glass microchannel etching mode a: Start the first peristaltic pump 3, turn off the second peristaltic pump 4, open the first micro valve 81 to fill the etching liquid channel with etchant A; close the first micro valve 81 and open the third micro valve 121 to allow etchant A to circulate in the etching liquid channel for 15 minutes. Step S43, Etching agent switching mode: Simultaneously turn on the first peristaltic pump 3 and the second peristaltic pump 4, close the third micro valve 121, and open the second micro valve 111 and the fourth micro valve 131 to replace etchant A in the etching liquid flow channel with etchant B; Step S44, Glass microchannel etching mode b: Turn off the first peristaltic pump 3, start the second peristaltic pump 4, close the second microvalve 111 and the fourth microvalve 131, open the sixth microvalve 171, and allow the etchant B to circulate in the etching liquid channel for 5 hours. Step S5: Remove the microfluidic etched chip 5, clean the glass substrate 51, and dry it with nitrogen to obtain a glass substrate 51 with glass microchannels formed.

[0076] The glass substrate 51 processed in Example 4 was observed using an optical microscope. The inner diameter of the glass microchannel was measured to be approximately 8 μm, and the surface roughness Ra value was maintained within 0.008 μm.

[0077] The technical principles of the present invention have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of the invention and should not be construed as limiting the scope of protection of the invention in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of the invention without inventive effort, and these embodiments will all fall within the scope of protection of the present invention.

Claims

1. A microfluidic-assisted wet etching apparatus for glass microchannels, characterized in that, The device includes a first storage container, a second storage container, a first peristaltic pump, a second peristaltic pump, a microfluidic etching chip, an ultrasonic temperature-controlled water bath device, and a recovery container. The first and second storage containers are used to store etching agents with different compositions and concentrations. The microfluidic etching chip is disposed within the ultrasonic temperature-controlled water bath device. The microfluidic etching chip includes a bonded glass substrate and a channel substrate. The glass substrate is pre-etched by laser to form pre-etched microchannels. The channel substrate has an inlet and an outlet. The inlet end of the pre-etched microchannel is connected to the inlet, and the outlet end of the pre-etched microchannel is connected to the outlet to form an etching liquid channel. The first storage container is connected to the first input terminal of the first peristaltic pump via a first inlet main pipe. The first inlet main pipe is equipped with a first micro valve. The first output terminal of the first peristaltic pump is connected to the inlet via a first inlet branch pipe. The outlet is connected to the second input terminal of the first peristaltic pump via a first outlet branch pipe. The second output terminal of the first peristaltic pump is connected to the recovery container via a first recovery liquid pipe. The first recovery liquid pipe is equipped with a second micro valve. A first circulation pipe is connected between the second output terminal of the first peristaltic pump and the second micro valve, and between the first micro valve and the first input terminal of the first peristaltic pump. The first circulation pipe is equipped with a third micro valve. The second storage container is connected to the third input terminal of the second peristaltic pump via a second inlet main pipe. The second inlet main pipe is equipped with a fourth micro valve. The third output terminal of the second peristaltic pump is connected to the inlet via a second inlet branch pipe. The outlet is connected to the fourth input terminal of the second peristaltic pump via a second outlet branch pipe. The fourth output terminal of the second peristaltic pump is connected to the recovery container via a second recovery liquid pipe. The second recovery liquid pipe is equipped with a fifth micro valve. A second circulation pipe is connected between the fourth output terminal of the second peristaltic pump and the fifth micro valve, and between the fourth micro valve and the third input terminal of the second peristaltic pump. The second circulation pipe is equipped with a sixth micro valve.

2. The microfluidic-assisted wet etching apparatus for glass microchannels according to claim 1, characterized in that, It also includes a third storage container and a third liquid inlet pipe. The third storage container is used to store the cleaning and protective agent. The input end of the third liquid inlet pipe is located inside the third storage container. The output end of the third liquid inlet pipe is connected to the first liquid inlet pipe, and the output end of the third liquid inlet pipe is located between the first micro valve and the first input end of the first peristaltic pump. The third liquid inlet main pipe is equipped with a seventh micro valve.

3. The microfluidic-assisted wet etching apparatus for glass microchannels according to claim 1, characterized in that, The pre-etched microchannels of the glass substrate are glass microgrooves or 3D microchannels, and the flow channel substrate is disposed on the upper end surface of the glass substrate. The flow channel substrate is also provided with auxiliary flow channels, and the auxiliary flow channels are respectively connected between the liquid inlet and the liquid inlet end of the pre-etched microchannel and between the liquid outlet end of the pre-etched microchannel and the liquid outlet.

4. The microfluidic-assisted wet etching apparatus for glass microchannels according to claim 1, characterized in that, The pre-etched microchannels of the glass substrate include multiple arrayed glass vias. The flow channel substrate includes an upper flow channel substrate and a lower flow channel substrate. The upper flow channel substrate is disposed on the upper end face of the glass substrate. The liquid inlet is disposed on the upper flow channel substrate. The lower flow channel substrate is disposed on the lower end face of the glass substrate. The liquid outlet is disposed on the lower flow channel substrate. The upper flow channel substrate is provided with a dispersion microchannel, the liquid inlet end of the dispersion microchannel is connected to the liquid inlet, and the liquid outlet end of the dispersion microchannel is provided in a one-to-one correspondence with the liquid inlet end of the glass through hole. The lower flow channel substrate is provided with a converging microchannel, and the liquid inlet end of the converging microchannel is provided in a one-to-one correspondence with the liquid outlet end of the glass through hole. The liquid outlet end of the converging microchannel is connected to the liquid outlet.

5. The microfluidic-assisted wet etching apparatus for glass microchannels according to claim 1, characterized in that, It also includes a micro mixer, which has two inlet ends. The first inlet branch pipe is connected to one of the inlet ends of the micro mixer, and the second inlet branch pipe is connected to the other inlet end of the micro mixer. The outlet end of the micro mixer is connected to the inlet.

6. The microfluidic-assisted wet etching apparatus for glass microchannels according to claim 1, characterized in that, It also includes a micro CCD camera, which is disposed on the outside of the ultrasonic temperature-controlled water bath device, with the imaging end of the micro CCD camera facing the ultrasonic temperature-controlled water bath device, and the position of the micro CCD camera aligned with the microfluidic etching chip. The microfluidic etching chip is positioned at the center of the ultrasonic temperature-controlled water bath device.

7. The microfluidic-assisted wet etching apparatus for glass microchannels according to claim 2, characterized in that, It also includes an industrial control computer, and the first peristaltic pump, the second peristaltic pump, the ultrasonic temperature-controlled water bath device, the first micro valve, the second micro valve, the third micro valve, the fourth micro valve, the fifth micro valve, the sixth micro valve and the seventh micro valve are respectively connected to the industrial control computer.

8. A microfluidic-assisted wet etching method for glass microchannels, characterized in that, The microfluidic-assisted wet etching apparatus for glass microchannels as described in claim 1, wherein the microfluidic-assisted wet etching method for glass microchannels comprises the following steps: Step S1: Pretreatment of glass substrate: Clean and dry the glass substrate. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate, and laser processing forms pre-etched microchannels on the glass substrate; Step S3, Microfluidic etching chip fabrication: The glass substrate and the flow channel substrate are bonded together to obtain the microfluidic etching chip; Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etchant A to the first storage container and etchant B to the second storage container. Start the ultrasonic temperature-controlled water bath device and place the microfluidic etching chip in the ultrasonic temperature-controlled water bath device. Step S42, Glass microchannel etching mode a: Start the first peristaltic pump, turn off the second peristaltic pump, open the first microvalve to fill the etching liquid channel with etchant A; close the first microvalve, open the third microvalve to allow etchant A to circulate within the etching liquid channel; Step S43, Etching agent switching mode: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, close the third micro valve, and open the second micro valve and the fourth micro valve to replace etchant A in the etching liquid flow channel with etchant B; Step S44, Glass microchannel etching mode b: Turn off the first peristaltic pump, start the second peristaltic pump, close the second microvalve and the fourth microvalve, open the sixth microvalve, so that the etchant B circulates in the etching liquid channel; Step S5: Remove the microfluidic etched chip, clean the glass substrate, and dry it with nitrogen gas to obtain a glass substrate with glass microchannels formed.

9. A microfluidic-assisted wet etching method for glass microchannels, characterized in that, The microfluidic-assisted wet etching apparatus for glass microchannels as described in claim 2, wherein the microfluidic-assisted wet etching method for glass microchannels comprises the following steps: Step S1: Pretreatment of glass substrate: Clean and dry the glass substrate. Step S2, Ultrafast Laser Modification: Laser pre-etching is performed on the glass substrate, and laser processing forms pre-etched microchannels on the glass substrate; Step S3, Microfluidic etching chip fabrication: The glass substrate and the flow channel substrate are bonded together to obtain the microfluidic etching chip; Step S4, Wet etching of glass microchannels: Step S41, Preparation before etching: Add etchant A to the first storage container, add etchant B to the second storage container, add cleaning and protective agent to the third storage container, start the ultrasonic temperature-controlled water bath device, and place the microfluidic etching chip in the ultrasonic temperature-controlled water bath device. Step S42, Glass microchannel cleaning mode: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, open the seventh microvalve and the fifth microvalve, so that the cleaning protectant enters the etching liquid channel and cleans the pre-etched microchannel; Step S43, Glass microchannel etching mode a: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, close the seventh microvalve, open the first microvalve and the fifth microvalve, so that the cleaning and protective agent in the etching liquid channel is replaced with etchant A, then turn off the second peristaltic pump, close the first microvalve and the fifth microvalve, open the third microvalve, so that etchant A circulates in the etching liquid channel; Step S44, Glass microchannel protection mode a: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, close the third microvalve, and open the fifth microvalve and the seventh microvalve, so that the etchant A in the etching liquid channel is replaced with the cleaning and protective agent; Step S45, Glass microchannel protection mode b: Simultaneously turn on the first peristaltic pump and the second peristaltic pump, close the fifth microvalve and the seventh microvalve, and open the fourth microvalve and the second microvalve, so that the cleaning protectant in the etching liquid channel is replaced with etching agent B; Step S46, Glass microchannel etching mode b: Turn off the first peristaltic pump, start the second peristaltic pump, close the fourth microvalve and the second microvalve, open the sixth microvalve, so that the etchant B can circulate in the etching liquid channel; Step S5: Remove the microfluidic etched chip, clean the glass substrate, and dry it with nitrogen gas to obtain a glass substrate with glass microchannels formed.

10. The microfluidic-assisted wet etching method for glass microchannels according to claim 9, characterized in that, The ultrasonic temperature-controlled water bath device has an ultrasonic power of 35W-70W, an ultrasonic frequency of 5Hz-25Hz, an ultrasonic amplitude of 0.6mm-1.8mm, and a water bath temperature of 40℃-80℃.

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