Etching method and etching apparatus

Abstract

The invention discloses an etching method and an etching apparatus, comprising the following etching steps: a first etching step of spraying a first etching liquid and compressed air on the surface of an etching object by using a two-fluid nozzle so as to etch the etching object; a second etching step in which compressed air and a second etching solution are simultaneously sprayed onto the etched object etched in the first etching step using a two-fluid nozzle; the pressure of the compressed air of the two-fluid nozzle in the first etching process is smaller than that of the compressed air of the two-fluid nozzle in the second etching process, and the etching rate of the second etching liquid is smaller than that of the first etching liquid. The invention belongs to the technical field of etching, and aims to solve the problems of high compressed air demand and low etching rate of a two-fluid etching technology in the prior art. The technical effects are that the optimal etching effect is guaranteed, the demand quantity of compressed air is reduced, and the etching rate is increased.

Description

Technical Field

[0001] The invention relates to the technical field of etching, in particular to an etching method and an etching device. Background Art

[0002] The etching process is a basic process in the production of circuit boards. It refers to the process of using etching liquid to etch away the copper on the circuit substrate that is not protected by the anti-corrosion layer, and finally forming a conductive circuit.

[0003] With the development of science and technology, the requirements for circuit precision are getting higher and higher, and the industry has put forward higher requirements for the production of substrate etching circuits; the existing technology mainly adopts two etching technologies, one-fluid nozzle etching or two-fluid etching, but the use of one-fluid nozzle etching often has the problem that the circuit clarity does not meet the process requirements; although the use of two-fluid etching technology can make the circuit clarity meet the process requirements, the existing two-fluid etching technology has problems such as large demand for compressed air, slow etching rate and high energy consumption. Summary of the invention

[0004] To this end, the present invention provides an etching device to solve the above-mentioned problems in the prior art.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] According to a first aspect of the present invention, an etching method comprises the following etching steps:

[0007] In a first etching step, a first etching solution and compressed air are sprayed onto a surface of an etching object using a two-fluid nozzle to etch the etching object;

[0008] In a second etching process, compressed air and a second etching liquid are sprayed simultaneously onto the etching object after the etching in the first etching process using a two-fluid nozzle;

[0009] The pressure of the compressed air of the two-fluid nozzle in the first etching process is lower than the pressure of the compressed air of the two-fluid nozzle in the second etching process, and the etching rate of the second etching liquid is lower than the etching rate of the first etching liquid.

[0010] Furthermore, the first etching solution and the second etching solution are both mixed solutions of HCl and NaClO 3 , and the HCl concentration of the first etching solution is greater than the HCl concentration of the second etching solution.

[0011] Further, the HCl concentration of the first etching solution is 1.5 mol / L to 2.5 mol / L, and the HCl concentration of the second etching solution is 0.3 mol / L to 0.5 mol / L.

[0012] Furthermore, the pressure of the compressed air of the two-fluid nozzle in the first etching process is 2.0 bar, and the pressure of the compressed air of the two-fluid nozzle in the second etching process is 3.0 bar.

[0013] According to a first aspect of the present invention, an etching device includes a first body, a second body, a first water pump, a second water pump, an air pump, a plurality of first two-fluid nozzles and a plurality of second two-fluid nozzles, a first etching liquid is arranged in the first body, a second etching liquid is arranged in the second body, a water outlet of the first water pump is connected to the plurality of first two-fluid nozzles through a water pipe, a water outlet of the second water pump is connected to the plurality of second two-fluid nozzles through a water pipe, a water inlet of the first water pump is connected to the first body through a pipeline and is connected to the first etching liquid, a water inlet of the second water pump is connected to the second body through a pipeline and is connected to the second etching liquid, a plurality of first two-fluid nozzles and a plurality of second two-fluid nozzles are all connected to the air pipe and the air pump, a plurality of first two-fluid nozzles are all installed in the first body, and a plurality of second two-fluid nozzles are all installed in the second body.

[0014] Furthermore, it also includes a third water pump, a first suction head, a fourth water pump and a second suction head, the water inlet of the third water pump is connected to the multiple first suction heads through a water pipe, the water outlet of the third water pump is connected to the first body through a water pipe and connected to the first etching liquid, the water inlet of the fourth water pump is connected to the multiple second suction heads through a water pipe, and the water outlet of the fourth water pump is connected to the second body through a water pipe and connected to the second etching liquid.

[0015] Furthermore, it also includes a first venturi tube and a second venturi tube, one end of the first venturi tube is connected to the third water pump through a water pipe, the other end of the first venturi tube is connected to the first body through a water pipe and connected to the first etching liquid, the middle part of the first venturi tube is connected to multiple first suction heads through a water pipe, one end of the second venturi tube is connected to the fourth water pump through a water pipe, the other end of the second venturi tube is connected to the second body through a water pipe and connected to the second etching liquid, and the middle part of the second venturi tube is connected to multiple second suction heads through a water pipe.

[0016] Furthermore, it also includes a first automatic regulating valve and a second automatic regulating valve. The first automatic regulating valve is arranged on the water pipe between the first water pump and the multiple first and second fluid nozzles, on the water pipe between the third water pump and the first venturi tube, and on the air pipe between the air pump and the multiple first and second fluid nozzles. The second automatic regulating valve is arranged on the water pipe between the second water pump and the multiple second and second fluid nozzles, on the water pipe between the fourth water pump and the second venturi tube, and on the air pipe between the air pump and the multiple second and second fluid nozzles.

[0017] Furthermore, it also includes a first pressure gauge and a second pressure gauge. The first pressure gauge is arranged on the water pipe between the first water pump and the multiple first and second fluid nozzles, on the water pipe between the third water pump and the first venturi tube, and on the air pipe between the air pump and the multiple first and second fluid nozzles. The second pressure gauge is arranged on the water pipe between the second water pump and the multiple second and second fluid nozzles, on the water pipe between the fourth water pump and the second venturi tube, and on the air pipe between the air pump and the multiple second and second fluid nozzles.

[0018] Furthermore, it also includes a conveying mechanism, which is used to convey the etching object. Multiple first two-fluid nozzles are respectively arranged on the upper and lower sides of the conveying mechanism, and multiple second two-fluid nozzles are respectively arranged on the upper and lower sides of the conveying mechanism. The first body and the second body are both connected to the conveying mechanism.

[0019] The present invention has the following advantages: by using the first etching liquid for the first etching process and the second etching liquid for the second etching process, the above etching method can reduce the use of compressed air by more than 30% compared with traditional two-fluid etching; the etching rate is increased by more than 20% while ensuring the best etching effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0021] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0022] Figure 1 A schematic structural diagram of an etching device used in the first etching process of an etching method provided in some embodiments of the present invention.

[0023] Figure 2 A schematic structural diagram of an etching device used in the second etching process of the etching method provided in some embodiments of the present invention.

[0024] Figure 3 A schematic structural diagram of an initial etching stage of an etching object of an etching device provided in some embodiments of the present invention.

[0025] Figure 4 A schematic structural diagram of an etching object of an etching device provided in some embodiments of the present invention after being etched through a first etching process.

[0026] Figure 5 A schematic structural diagram of an etching object of an etching device provided in some embodiments of the present invention after etching is completed through a second etching process.

[0027] In the figure: 101, first body, 102, first suction head, 103, first water pump, 104, first venturi tube, 105, first two-fluid nozzle, 106, air pump, 107, first gas filter, 108, third water pump, 109, first liquid filter, 110, first automatic regulating valve, 111, first pressure gauge, 112, first etching liquid, 114, first liquid collecting tank, 201, second body, 202, second suction head, 2 03. Second water pump, 204. Second venturi tube, 205. Second two-fluid nozzle, 207. Second gas filter, 208. Fourth water pump, 209. Second liquid filter, 210. Second automatic regulating valve, 211. Second pressure gauge, 212. Second etching liquid, 214. Second collecting tank, 3. Etching object, 31. Substrate, 32. Conductive layer, 33. Anti-corrosion layer, 4. Conveying mechanism, 41. Lower roller, 42. Upper roller. DETAILED DESCRIPTION

[0028] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] like Figures 1 to 5 As shown, an etching method in an embodiment of the first aspect of the present invention comprises the following etching steps:

[0030] In the first etching process, a two-fluid nozzle is used to spray the first etching solution 112 and compressed air onto the surface of the etching object 3 so as to etch the etching object 3;

[0031] In the second etching process, compressed air and the second etching liquid 212 are sprayed simultaneously onto the etching object 3 after the etching in the first etching process using a two-fluid nozzle;

[0032] The pressure of the compressed air of the two-fluid nozzle in the first etching process is lower than that of the compressed air of the two-fluid nozzle in the second etching process, and the etching rate of the second etching solution 212 is lower than that of the first etching solution 112 .

[0033] In the above embodiment, it should be noted that the two-fluid nozzle in the first etching process and the two-fluid nozzle in the second etching process both spray compressed air directly toward the etching object 3. The first etching process is from the initial stage of etching to the mid-stage of etching. At this stage, the etching solution easily enters the middle of the circuit to etch the surface copper layer. Therefore, the equipment pressure is adjusted, and a small amount of compressed air is supplied with a smaller pressure to slightly reduce the particles of the etching solution; the desired etching effect can be achieved. At this stage, the first etching solution, i.e., a solution with a faster etching rate, is used to achieve the purpose of quickly etching the surface copper layer; the second etching process is from the mid-stage of etching to the final etching stage. At this stage, the copper layer of the circuit is at the root of the circuit, and it is difficult for the solution to enter the root of the circuit for etching. At this stage, the equipment pressure needs to be adjusted, and a large amount of compressed air is outputted with a larger pressure to make the particles of the etching solution very small, so as to achieve the ideal etching of the copper layer at the root of the circuit. At the same time, in order to further improve the etching accuracy, the etching solution uses the second etching solution, i.e., a solution with a slower etching rate, to better protect the side of the circuit, reduce side corrosion, thereby improving the etching factor, and finally achieving the ideal etching effect.

[0034] The technical effects achieved by the above embodiments are: compared with the traditional two-fluid etching, the above etching method can reduce the use of compressed air by more than 30%; the etching rate is increased by more than 20% while ensuring the best etching effect.

[0035] Optional, such as Figures 1 to 5 As shown, in some embodiments, the first etching solution 112 and the second etching solution 212 are both mixed solutions of HCl and NaClO 3 , and the HCl concentration of the first etching solution 112 is greater than the HCl concentration of the second etching solution 212 .

[0036] The HCl concentration of the first etching solution 112 is 1.5 mol / L to 2.5 mol / L, and the HCl concentration of the second etching solution 212 is 0.3 mol / L to 0.5 mol / L.

[0037] The pressure of the compressed air in the two-fluid nozzle in the first etching process was 2.0 bar, and the pressure of the compressed air in the two-fluid nozzle in the second etching process was 3.0 bar.

[0038] In the above optional embodiments, it should be noted that, because the chemical formula of the etching object is Cu2Cl2; adding a mixed solution of HCl and NaClO3 to the etching object has the formula: Cu2Cl2+2HCl+NaClO3→2CuCl2+NaCl+H2O; in the production process, two kinds of potions, HCl and NaClO3, need to be added; the setting parameters of HCl in the two tanks are different, the etching rate of the first etching solution is 60 seconds to 90 seconds for an etching thickness of 35 μm, and the etching rate of the first etching solution is 180 seconds to 200 seconds for an etching thickness of 35 μm, and the parameters of the oxidant NaClO3 of the first etching solution are the same as the parameters of the oxidant NaClO3 of the second etching solution, both of which have an oxidation-reduction potential of 500mv-550mv.

[0039] The two-fluid nozzles of the first etching process and the two-fluid nozzles of the second etching process both use 6010-model two-fluid nozzles.

[0040] The pressure of the compressed air sprayed from the two-fluid nozzle in the first etching process is 2.0 bar, and the amount of compressed air sprayed from each two-fluid nozzle is 36NL / min. The pressure of the compressed air sprayed from the two-fluid nozzle in the second etching process is 3.0 bar, and the amount of compressed air sprayed from each two-fluid nozzle is 58NL / min. The pressure of the compressed air sprayed from the two-fluid nozzle in the traditional two-fluid etching scheme is 3.0 bar, and the amount of compressed air sprayed from each two-fluid nozzle is 58NL / min. After calculation, the total compressed air consumption of this scheme is 81% of the compressed air consumption of the traditional scheme.

[0041] The compressed air sprayed from the two-fluid nozzle in the first etching process slightly reduces the size of the first etching solution particles, so that the average particle size of the first etching solution is 30 μm, thereby achieving the effect of quickly etching the surface copper layer.

[0042] The compressed air ejected from the two-fluid nozzle in the second etching process changes the average particle size of the second etching liquid to 20μm, allowing the liquid to reach the root of the circuit.

[0043] In traditional two-fluid etching, the etching solution uses a solution with HCL addition setting parameters of 0.3mol / L-0.5mol / L. The etching rate of this solution is 1 / 2 of the solution with HCL addition setting parameters of 1.5mol / L-2.5mol / L; therefore, the etching rate of the two parts of the two-fluid etching of the present application is 1.5 times the traditional two-fluid etching rate.

[0044] The technical effect achieved by the above optional embodiments is: by using etching solutions with different etching rates in different processes in combination with compressed air of different pressures and different amounts of compressed air, it is possible to reduce the use of compressed air and increase the etching rate while ensuring the etching effect, thereby indirectly reducing energy consumption.

[0045] The initial state of the etched object is as follows Figure 3 As shown, it includes a substrate 31 , a conductive layer 32 and an anti-corrosion layer 33 . Continuous conductive layers 32 are provided on both sides of the substrate 31 , and an anti-corrosion layer 33 is provided on the side of each conductive layer 32 facing away from the substrate 31 .

[0046] The structure of the etching object obtained in the first etching step is as follows Figure 4 As shown, the conductive layer 32 on both sides of the substrate 31 is rapidly etched to form a truncated cone.

[0047] The structure of the etching object obtained in the second etching step is as follows Figure 5 As shown, the final etching object is formed.

[0048] The second aspect of the present invention provides an etching device, comprising a first body 101, a second body 201, a first water pump 103, a second water pump 203, an air pump 106, a plurality of first two-fluid nozzles 105 and a plurality of second two-fluid nozzles 205, wherein a first etching liquid 112 is arranged in the first body 101, a second etching liquid 212 is arranged in the second body 201, a water outlet of the first water pump 103 is connected to the plurality of first two-fluid nozzles 105 through a water pipe, and a water outlet of the second water pump 203 is connected to the plurality of second two-fluid nozzles 212 through a water pipe. The fluid nozzle 205 is connected, the water inlet of the first water pump 103 is connected to the first body 101 through a pipeline and connected to the first etching liquid 112, the water inlet of the second water pump 203 is connected to the second body 201 through a pipeline and connected to the second etching liquid 212, multiple first two-fluid nozzles 105 and multiple second two-fluid nozzles 205 are connected to the air pump 106 through an air pipe, multiple first two-fluid nozzles 105 are installed in the first body 101, and multiple second two-fluid nozzles 205 are installed in the second body 201.

[0049] In the above optional embodiment, it should be noted that it also includes a first gas filter 107, a second gas filter 207, a first liquid filter 109 and a second liquid filter 209, a first liquid collecting tank 114 and a second liquid collecting tank 214. The first liquid collecting tank 114 is arranged at the bottom of the first body 101, and the second liquid collecting tank 214 is arranged at the bottom of the second body 201. The first gas filter 107 is connected to the air pipe connecting the air pump 106 and the plurality of first two-fluid nozzles 105, and the second gas filter 207 is connected to the air pipe connecting the air pump 106 and the plurality of second two-fluid nozzles 205. The first etching liquid 11 is placed in the first liquid collecting tank 114, and the second etching liquid 21 is placed in the second liquid collecting tank 214; when performing the first etching process, the plurality of first two-fluid nozzles 105 are respectively placed on both sides of the etching object 3; when performing the second etching process, the plurality of second two-fluid nozzles 205 are respectively placed on both sides of the etching object 3 after etching by the first etching process.

[0050] The beneficial effects of the above optional embodiments are: the setting of the air pump 106 provides sufficient compressed air and sufficient pressure for the first two-fluid nozzle 105 of the first etching process, and the setting of the first water pump 103 provides sufficient power for the first etching liquid 101 to enter the first two-fluid nozzle 105; at the same time, the setting of the air pump 106 provides sufficient compressed air and sufficient pressure for the second two-fluid nozzle 205 of the second etching process, and the setting of the second water pump 203 provides sufficient power for the second etching liquid 201 to enter the second two-fluid nozzle 205.

[0051] Optional, such as Figures 1 to 5 As shown, in some embodiments, a third water pump 108, a first suction head 102, a fourth water pump 208 and a second suction head 202 are further included. The water inlet of the third water pump 108 is connected to the multiple first suction heads 102 through a water pipe, the water outlet of the third water pump 108 is connected to the first body 101 through a water pipe and is connected to the first etching liquid 11, the water inlet of the fourth water pump 208 is connected to the multiple second suction heads 202 through a water pipe, and the water outlet of the fourth water pump 208 is connected to the second body 201 through a water pipe and is connected to the second etching liquid 212.

[0052] The beneficial effects of the above optional embodiments are as follows: the first etching liquid 101 remaining on the surface of the etching object 3 in the first etching process can be absorbed into the first liquid collecting tank 114 for secondary use by the third water pump 108 in cooperation with the first suction head 102, and the second etching liquid 201 remaining on the surface of the etching object 3 in the second etching process can be absorbed into the second liquid collecting tank 224 for secondary use by the fourth water pump 208 in cooperation with the second suction head 202, thereby avoiding waste of etching liquid.

[0053] Optional, such as Figures 1 to 5As shown, in some embodiments, a first venturi tube 104 and a second venturi tube 204 are further included, one end of the first venturi tube 104 is connected to the third water pump 108 through a water pipe, the other end of the first venturi tube 104 is connected to the first body 101 through a water pipe and connected to the first etching liquid 11, the middle part of the first venturi tube 104 is connected to the plurality of first suction heads 102 through a water pipe, one end of the second venturi tube 204 is connected to the fourth water pump 208 through a water pipe, the other end of the second venturi tube 204 is connected to the second body 201 through a water pipe and connected to the second etching liquid 21, and the middle part of the second venturi tube 204 is connected to the plurality of second suction heads 202 through a water pipe.

[0054] Optional, such as Figures 1 to 5 As shown, in some embodiments, a first automatic regulating valve 110 and a second automatic regulating valve 210 are also included. The first automatic regulating valve 110 is arranged on the water pipe between the first water pump 103 and the multiple first two-fluid nozzles 105, on the water pipe between the third water pump 108 and the first venturi tube 104, and on the air pipe between the air pump 106 and the multiple first two-fluid nozzles 105. The second automatic regulating valve 210 is arranged on the water pipe between the second water pump 203 and the multiple second two-fluid nozzles 205, on the water pipe between the fourth water pump 208 and the second venturi tube 204, and on the air pipe between the air pump 106 and the multiple second two-fluid nozzles 205.

[0055] In the above optional embodiments, it should be noted that both the first automatic regulating valve 110 and the second automatic regulating valve 210 are throttle valves.

[0056] The beneficial effects of the above optional embodiments are as follows: by setting up a plurality of first automatic regulating valves 110, it is possible to adjust the compressed air supply amount of the first etching process, the supply amount of the first etching liquid 101, and the absorption pressure of the first etching liquid 101 remaining on the surface of the etching object 3, thereby ensuring the initial etching effect of the first etching process on the etching object 3; by setting up a plurality of second automatic regulating valves 210, it is possible to adjust the compressed air supply amount of the second etching process, the supply amount of the second etching liquid 201, and the absorption pressure of the second etching liquid 201 remaining on the surface of the etching object 3, thereby ensuring the etching effect of the second etching process on the etching object 3 and ensuring the final etching effect of the etching object 3.

[0057] Optional, such as Figures 1 to 5As shown, in some embodiments, a first pressure gauge 111 and a second pressure gauge 211 are also included. The first pressure gauge 11 is arranged on the water pipe between the first water pump 103 and the multiple first two-fluid nozzles 105, on the water pipe between the third water pump 108 and the first venturi tube 104, and on the air pipe between the air pump 106 and the multiple first two-fluid nozzles 105. The second pressure gauge 211 is arranged on the water pipe between the second water pump 203 and the multiple second two-fluid nozzles 205, on the water pipe between the fourth water pump 208 and the second venturi tube 204, and on the air pipe between the air pump 106 and the multiple second two-fluid nozzles 205.

[0058] The beneficial effects of the above optional embodiments are as follows: by setting the first pressure gauge 111, the compressed air supply pressure of the first etching process and the supply pressure of the first etching liquid 101 can be monitored in real time to ensure that the compressed air supply pressure of the first etching process and the supply pressure of the first etching liquid 101 are within the required pressures; by setting the second pressure gauge 211, the compressed air supply pressure of the second etching process and the supply pressure of the second etching liquid 201 can be monitored in real time to ensure that the compressed air supply pressure of the second etching process and the supply pressure of the second etching liquid 201 are within the required pressures.

[0059] Optional, such as Figures 1 to 5 As shown, in some embodiments, a conveying mechanism 4 is also included, and the conveying mechanism 4 is used to convey the etching object 3. A plurality of first two-fluid nozzles 105 are respectively arranged on the upper and lower sides of the conveying mechanism 4, and a plurality of second two-fluid nozzles 205 are respectively arranged on the upper and lower sides of the conveying mechanism 4. The first body 101 and the second body 201 are both connected to the conveying mechanism 4.

[0060] In the above optional embodiment, it should be noted that the conveying mechanism 4 includes a plurality of lower rollers 41, a plurality of lower rollers 42 and a driving motor. The upper rollers 42 are placed one by one above the lower rollers 41, and the spur gears of the lower rollers 41 drive the spur gears of the upper rollers 42. When the etching object passes by, the upper rollers will be lifted up and pressed on the etching object to prevent the lower spray from flushing the product. The driving motor is used to drive the plurality of upper rollers 41 and the plurality of lower rollers 42 to rotate.

[0061] The beneficial effect of the above optional embodiment is that the etching object 3 can be transported by setting the transport mechanism 4 .

[0062] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

[0063] The terms such as "upper", "lower", "left", "right", "middle", etc. cited in this specification are only for the convenience of description and are not intended to limit the scope of implementation of the present invention. Changes or adjustments to their relative relationships should be regarded as within the scope of implementation of the present invention without substantially changing the technical content.

Claims

1. An etching method, characterized in that: Etching process: In a first etching process, a first etching liquid (112) and compressed air are sprayed onto a surface of an etching object (3) using a two-fluid nozzle, thereby etching the etching object (3); A second etching process, using a two-fluid nozzle to simultaneously spray compressed air and a second etching liquid (212) onto the etching object (3) after the etching is completed in the first etching process; The pressure of the compressed air of the two-fluid nozzle in the first etching process is lower than the pressure of the compressed air of the two-fluid nozzle in the second etching process, and the etching rate of the second etching liquid (212) is lower than the etching rate of the first etching liquid (112).

2. The etching method according to claim 1, characterized in that: The first etching solution (112) and the second etching solution (212) are both mixed solutions of HCl and NaClO3, and the HCl concentration of the first etching solution (112) is greater than the HCl concentration of the second etching solution (212).

3. The etching method according to claim 2, characterized in that: The HCl concentration of the first etching solution (112) is 1.5 mol / L to 2.5 mol / L, and the HCl concentration of the second etching solution (212) is 0.3 mol / L to 0.5 mol / L.

4. The etching method according to claim 1, characterized in that: The pressure of the compressed air of the two-fluid nozzle in the first etching process is 2.0 bar, and the pressure of the compressed air of the two-fluid nozzle in the second etching process is 3.0 bar.

5. An etching device, characterized in that: The invention comprises a first body (101), a second body (201), a first water pump (103), a second water pump (203), an air pump (106), a plurality of first two-fluid nozzles (105) and a plurality of second two-fluid nozzles (205), wherein a first etching liquid (112) is arranged in the first body (101), a second etching liquid (212) is arranged in the second body (201), a water outlet of the first water pump (103) is connected to the plurality of the first two-fluid nozzles (105) through a water pipe, a water outlet of the second water pump (203) is connected to the plurality of the second two-fluid nozzles (205) through a water pipe, and the first The water inlet of the water pump (103) is connected to the first body (101) through a pipeline and communicated with the first etching liquid (112); the water inlet of the second water pump (203) is connected to the second body (201) through a pipeline and communicated with the second etching liquid (212); a plurality of the first two-fluid nozzles (105) and a plurality of the second two-fluid nozzles (205) are connected to a plurality of the air pumps (106) through air pipes; the plurality of the first two-fluid nozzles (105) are installed in the first body (101); and the plurality of the second two-fluid nozzles (205) are installed in the second body (201).

6. An etching device according to claim 5, characterized in that: The invention also comprises a third water pump (108), a first suction head (102), a fourth water pump (208) and a second suction head (202); the water inlet of the third water pump (108) is connected to the plurality of first suction heads (102) through a water pipe; the water outlet of the third water pump (108) is connected to the first body (101) through a water pipe and is connected to the first etching liquid (112); the water inlet of the fourth water pump (208) is connected to the plurality of second suction heads (202) through a water pipe; the water outlet of the fourth water pump (208) is connected to the second body (201) through a water pipe and is connected to the second etching liquid (212).

7. An etching device according to claim 6, characterized in that: The invention also comprises a first venturi tube (104) and a second venturi tube (204), wherein one end of the first venturi tube (104) is connected to the third water pump (108) through a water pipe, the other end of the first venturi tube (104) is connected to the first body (101) through a water pipe and is connected to a first etching liquid (112), the middle part of the first venturi tube (104) is connected to a plurality of the first suction heads (102) through a water pipe, one end of the second venturi tube (204) is connected to the fourth water pump (208) through a water pipe, the other end of the second venturi tube (204) is connected to the second body (201) through a water pipe and is connected to a second etching liquid (212), and the middle part of the second venturi tube (204) is connected to a plurality of the second suction heads (202) through a water pipe.

8. An etching device according to claim 7, characterized in that: It also includes a first automatic regulating valve (110) and a second automatic regulating valve (210). The first automatic regulating valve (110) is arranged on the water pipe between the first water pump (103) and the plurality of the first two-fluid nozzles (105), on the water pipe between the third water pump (108) and the first venturi tube (104), and on the air pipe between the air pump (106) and the plurality of the first two-fluid nozzles (105). The second automatic regulating valve (210) is arranged on the water pipe between the second water pump (203) and the plurality of the second two-fluid nozzles (205), on the water pipe between the fourth water pump (208) and the second venturi tube (204), and on the air pipe between the air pump (106) and the plurality of the second two-fluid nozzles (205).

9. An etching device according to claim 8, characterized in that: It also includes a first pressure gauge (111) and a second pressure gauge (211). The first pressure gauge (111) is arranged on the water pipe between the first water pump (103) and the plurality of the first two-fluid nozzles (105), on the water pipe between the third water pump (108) and the first venturi tube (104), and on the air pipe between the air pump (106) and the plurality of the first two-fluid nozzles (105). The second pressure gauge (211) is arranged on the water pipe between the second water pump (203) and the plurality of the second two-fluid nozzles (205), on the water pipe between the fourth water pump (208) and the second venturi tube (204), and on the air pipe between the air pump (106) and the plurality of the second two-fluid nozzles (205).

10. An etching device according to claim 5, characterized in that: It also includes a conveying mechanism (4), which is used to convey the etching object (3), and a plurality of the first two-fluid nozzles (105) are respectively arranged on the upper and lower sides of the conveying mechanism (4), and a plurality of the second two-fluid nozzles (205) are respectively arranged on the upper and lower sides of the conveying mechanism (4), and the first body (101) and the second body (201) are both connected to the conveying mechanism (4).

Images