A wet etching apparatus and a wet etching method

Abstract

The application discloses a kind of wet etching device and wet etching method, it is related to wet etching technical field, including bearing frame, manipulator, water bath heating module, etching groove and cleaning tank, water bath heating module surrounds etching groove, etching groove surrounds cleaning tank;Manipulator is used to control bearing frame motion in etching groove;Water bath heating module is used to control the temperature of etching groove;Etching groove is annular structure or back shape structure, and the bottom of etching groove is provided with several air inlets;Cleaning tank is used to clean after etching wafer.The application is controlled bearing frame motion in etching groove by manipulator, and by setting air inlet in etching groove, improve the temperature uniformity of chemical liquid system, reduce the fluctuation of local temperature of chemical liquid, carry out temperature control to etching groove by water bath heating module, reduce the influence of environmental temperature change on chemical liquid temperature, finally keep etching rate stable, obtain good etching effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wet etching, in particular to a wet etching device and a wet etching method. BACKGROUND

[0002] Wet etching is a common means in the process of LED chip manufacturing, which separates the etched material from the wafer through the chemical reaction between the chemical liquid and the etched material. Generally, the operator will immerse the wafer rack containing multiple wafers into the etching tank containing the corresponding chemical liquid for batch etching, which has low production cost and high production capacity.

[0003] However, in the process of batch wet etching of wafers, due to the heat release phenomenon of etching reaction and environmental temperature change, the local temperature of the chemical liquid in the etching tank will fluctuate greatly, which will affect the etching rate and result in poor etching effect. SUMMARY

[0004] The present application aims to overcome the shortcomings of the prior art, and provides a wet etching device and a wet etching method, which improves the temperature uniformity of the chemical liquid system by controlling the movement of the carrier frame in the etching tank with a mechanical hand and ventilating by setting air inlet holes in the etching tank, reduces the fluctuation of the local temperature of the chemical liquid, stabilizes the etching rate, and obtains good etching effect; the temperature of the etching tank is controlled by the water bath heating module, which reduces the influence of environmental temperature change on the temperature of the chemical liquid, maintains the stability of the etching rate, and obtains good etching effect.

[0005] The present application provides a wet etching device, which comprises a carrier frame, a mechanical hand, a water bath heating module, an etching tank and a cleaning tank, the water bath heating module surrounds the etching tank, and the etching tank surrounds the cleaning tank.

[0006] The carrier frame is used to load the wafers to be etched, the mechanical hand is used to grab and move the carrier frame, and the mechanical hand is used to control the movement of the carrier frame in the etching tank.

[0007] The water bath heating module is used to control the temperature of the etching tank.

[0008] The etching tank has a ring structure or a loop structure, the bottom of the etching tank is provided with a plurality of air inlet holes, the etching tank is used to contain the chemical liquid, and the chemical liquid is used to etch the wafers.

[0009] The cleaning tank is used to clean the etched wafers.

[0010] Specifically, the carrier frame is a corrosion-resistant metal carrier frame.

[0011] Specifically, the mechanical hand has two.

[0012] Specifically, the interval between the plurality of air inlet holes is 1-5 cm.

[0013] The application further provides a wet etching method, comprising the following steps:

[0014] Normal water is added into the water bath heating module, corresponding chemical liquid is added into the etching tank, and deionized water is added into the cleaning tank;

[0015] The working temperature of the water bath heating module is set, and the wet etching device is started to preheat the normal water, the chemical liquid and the deionized water;

[0016] After the normal water, the chemical liquid and the deionized water all reach the set temperature, protective gas is introduced into the etching tank;

[0017] The mechanical arm is used to immerse the carrier frame loaded with a plurality of to-be-etched wafer pieces into the chemical liquid reaching the set temperature for etching, and the carrier frame loaded with a plurality of to-be-etched wafer pieces is controlled to move circularly in the etching tank;

[0018] After etching for a set time, the mechanical arm is used to put the etched wafer pieces together with the carrier frame into the cleaning tank for cleaning.

[0019] Specifically, the circular motion rate of the carrier frame is 10-100 cm / min.

[0020] Specifically, the set time is 1-20 min.

[0021] Specifically, the protective gas comprises a mixture of one or more of nitrogen, helium and argon.

[0022] Specifically, the flow rate of the protective gas is 0.5-10 cc / cm 2 .

[0023] Specifically, the mechanical arm is used to immerse the carrier frame loaded with a plurality of to-be-etched wafer pieces into the chemical liquid reaching the set temperature for etching, and the carrier frame loaded with a plurality of to-be-etched wafer pieces is controlled to move circularly in the etching tank, comprising:

[0024] The first mechanical arm is used to immerse the first carrier frame loaded with a plurality of to-be-etched wafer pieces into the chemical liquid reaching the set temperature for etching, and the first carrier frame is on one side of the etching tank;

[0025] The second mechanical arm is used to immerse the second carrier frame loaded with a plurality of to-be-etched wafer pieces into the chemical liquid reaching the set temperature for etching, and the second carrier frame is on the other side of the etching tank;

[0026] The first carrier frame and the second carrier frame keep relative positions and simultaneously move in one direction.

[0027] Compared with the prior art, the present application has the following advantages:

[0028] The mechanical hand controls the carrier frame to move in the etching tank with annular or loop structure, so that the heat generated by the etching reaction can be dispersed in the whole chemical liquid system in time, the local temperature of the chemical liquid is prevented from rising rapidly, the etching rate is prevented from being too fast, and the etching effect is affected; the chemical liquid can be agitated, so that the chemical liquid flows in the etching tank, the temperature uniformity of the chemical liquid is improved, the etching rate is kept stable, and the wafer gets better etching effect.

[0029] The gas is introduced into the etching tank through the gas inlet hole arranged below the etching tank, so that the chemical liquid at the bottom and the upper layer of the etching tank is agitated, the temperature of the chemical liquid is uniform, the etching rate of the wafer is kept consistent, and good etching effect is obtained.

[0030] The water bath heating module controls the temperature of the etching tank, so that the influence of the environmental temperature change on the temperature of the chemical liquid is reduced, the temperature fluctuation of the chemical liquid is reduced, the temperature of the chemical liquid is kept stable, the etching rate is kept stable, and the wafer gets good etching effect. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0032] Figure 1 is a top view of the wet etching device in the embodiment of the present application;

[0033] Figure 2 is a flow chart of the wet etching method in the embodiment of the present application;

[0034] Figure 3 is a wet etching flow chart of the GaN wafer passivation layer in the embodiment of the present application.

[0035] In the drawings, 100 is a carrier frame; 200 is a water bath heating module; 300 is an etching tank; 310 is a gas inlet hole; and 400 is a cleaning tank. DETAILED DESCRIPTION

[0036] Clearly and completely, the technical solutions in the embodiments of the present application will be described in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0037] Embodiment one:

[0038] Figure 1 A top view of a wet etching device in an embodiment of the present application is shown, which comprises a carrier frame 100, a mechanical hand, a water bath heating module 200, an etching tank 300 and a cleaning tank 400, the water bath heating module 200 surrounds the etching tank 300, the etching tank 300 surrounds the cleaning tank 400; the carrier frame 100 is used to load the wafer to be etched, the mechanical hand is used to grab and move the carrier frame 100, and the mechanical hand is used to control the movement of the carrier frame 100 in the etching tank 300; the water bath heating module 200 is used to control the temperature of the etching tank 300; the etching tank 300 is of a ring structure or a loop structure, the bottom of the etching tank 300 is provided with a plurality of air inlet holes 310, the etching tank 300 is used to hold chemical liquid, and the chemical liquid is used to etch the wafer; the cleaning tank 400 is used to clean the etched wafer.

[0039] By controlling the movement of the carrier frame 100 in the etching tank 300 of a ring or loop structure by the mechanical hand, the heat generated by the etching reaction can be dispersed into the whole chemical liquid system in time, avoiding the rapid increase of the local temperature of the chemical liquid, leading to the fast etching rate and affecting the etching effect; the chemical liquid can also be stirred to flow in the etching tank, improving the temperature uniformity of the chemical liquid, keeping the stability of the etching rate, and making the wafer obtain better etching effect.

[0040] The bottom of the carrier frame 100 is provided with a rectangular opening opposite to the insertion port of the wafer, ensuring the smooth flow of the chemical liquid perpendicular to the insertion port direction; when the carrier frame 100 moves in the etching tank 300, the insertion port of the wafer faces the movement direction of the carrier frame 100, and the wafer is parallel to the liquid level of the chemical liquid, keeping the edge of the wafer facing the movement direction, so that the chemical liquid can fully flow through the surface of any wafer.

[0041] By setting the air inlet hole 310 below the etching tank, the chemical liquid is stirred by the introduced gas, so that the temperature of the chemical liquid in the bottom layer and the upper layer of the etching tank 300 is uniform and consistent, keeping the etching rate of the whole wafer consistent, and obtaining good etching effect.

[0042] The temperature control of the etching tank 300 by the water bath heating module 200 can reduce the influence of the environmental temperature change on the temperature of the chemical liquid, reduce the temperature fluctuation of the chemical liquid, maintain the stability of the temperature of the chemical liquid, maintain the stability of the etching rate, and make the wafer obtain good etching effect.

[0043] In some embodiments, the carrier 100 is a corrosion-resistant metal carrier. In the process of manufacturing the LED chip, the carrier 100 is widely used, and its main function is to load the wafer. Generally, it is made of rubber and can load 25 wafers. The wafer is in direct contact with the carrier 100. The embodiment of the application uses a corrosion-resistant metal carrier to utilize the good thermal conductivity of the metal to efficiently conduct and dissipate the heat generated by the wafer etching reaction into the chemical liquid, thereby avoiding the accumulation of heat on the wafer and affecting the etching rate of the wafer. The corrosion-resistant metal carrier can be made of nickel, copper, platinum, gold and other metals that are not easy to react with the chemical liquid, or can be made of stainless steel. At the same time, the surface of the corrosion-resistant metal carrier needs to be plated with a 5-10um corrosion-resistant layer, which is a metal oxide or a metal nitride, such as copper oxide and aluminum nitride. Specifically, the appropriate metal carrier should be selected according to the chemical properties of the chemical liquid used; preferably, stainless steel is used as the main body of the metal carrier, and then a corresponding acid-resistant corrosion-resistant layer or alkali-resistant corrosion-resistant layer is plated on the surface.

[0044] In some embodiments, the mechanical hand has two, which can simultaneously control two carriers 100 loaded with wafers to be etched to perform wafer etching, thereby improving production efficiency and utilization efficiency of the wet etching device.

[0045] In some embodiments, the interval between the plurality of gas inlet holes 310 is 1-5cm, and the gas inlet hole 310 is used to introduce gas. If the gas inlet hole 310 is too sparse, the gas cannot fully stir the chemical liquid, and the purpose of making the upper and lower layers of the chemical liquid consistent in temperature cannot be achieved. If the gas inlet hole 310 is too dense, it is easy to make the chemical liquid boil violently and splash everywhere.

[0046] Embodiment two:

[0047] Figure 2 The flowchart of the wet etching method in the embodiment of the application is shown, which includes the following steps:

[0048] S1, add ordinary water in the water bath heating module, add corresponding chemical liquid in the etching tank, and add deionized water in the cleaning tank.

[0049] The water bath heating module 200 is not communicated with the etching tank 300, and the water in the water bath heating module 200 is used for heat conduction, and thus has no special requirement on water quality, and thus ordinary water can be used; the chemical liquid is the existing one, and needs to be selected and used according to the specific etching purpose of the wafer; after the wafer etching is completed, the wafer is cleaned in the cleaning tank 400, and in order to avoid impurity pollution, deionized water needs to be used.

[0050] S2, set the working temperature of the water bath heating module, and start the wet etching device to preheat the ordinary water, the chemical liquid and the deionized water.

[0051] The wet etching needs a suitable temperature, and generally the higher the temperature, the faster the rate of the wet etching; the water bath heating module 200 is used to heat the chemical liquid in the etching tank 300, which can improve the temperature uniformity of the chemical liquid, and also can accurately control the working temperature of the chemical liquid, so as to ensure the stability of the etching rate of the wafer, and avoid that the etching rate is too high or too low, which leads to that the width of the etching line on the wafer exceeds the standard range.

[0052] The water bath heating module 200 can also serve as a temperature buffer barrier of the etching tank 300, which can effectively weaken the influence of the change of the external environment temperature on the temperature of the chemical liquid in the etching tank 300.

[0053] The water bath heating module 200 heats the chemical liquid in the etching tank 300, the chemical liquid in the etching tank 300 transmits heat to the deionized water in the cleaning tank 400, the temperature of the ordinary water, the chemical liquid and the deionized water is consistent, and all are preheated to the set working temperature; the deionized water in the cleaning tank 400 has a suitable temperature, and the cleaning effect is better, and the deionized water in the cleaning tank 400 can also serve as a temperature buffer barrier of the etching tank 300, which is beneficial to maintaining the temperature stability of the chemical liquid in the etching tank 300.

[0054] S3, after the ordinary water, the chemical liquid and the deionized water all reach the set temperature, protective gas is introduced into the etching tank.

[0055] In the process of the wet etching of the wafer, often the bubbles generated by the etching reaction are adsorbed on the surface of the wafer, forming a “pseudo mask”, which isolates the contact between the chemical liquid and the wafer, leading to that the etching of the pattern on the surface of the wafer is not complete, and affecting the photoelectric performance of the LED chip product. By introducing the protective gas into the chemical liquid in the etching tank 300, the rapidly rising bubbles can take away the bubbles generated by the etching reaction on the surface of the wafer, avoiding that the bubbles isolate the chemical liquid to affect the etching reaction on the surface of the wafer, so that the surface etching effect of the wafer is more uniform, and the etching quality is improved.

[0056] The protective gas can also agitate the chemical liquid at the bottom of the etching tank 300 to the surface layer, so that the temperature of the chemical liquid is more uniform, and the stability of the etching rate of the wafer is ensured.

[0057] The protective gas includes one or more of nitrogen, helium, and argon, is insoluble in the chemical liquid, does not react with the chemical liquid, and does not react with the wafer; preferably, nitrogen is used because of its low cost.

[0058] The flow rate of the protective gas is 0.5-10 cc / cm 2 If the flow rate of the protective gas is too low, the effect of removing bubbles and agitating the chemical liquid is poor; if the flow rate of the protective gas is too high, the chemical liquid is easily blown out of the etching tank 300, which is dangerous.

[0059] The protective gas not only agitates the chemical liquid to make the upper and lower layers of the chemical liquid have the same temperature, but also carries away the bubbles generated by the etching reaction on the surface of the wafer and adsorbed on the surface of the wafer, avoids the bubbles from isolating the chemical liquid to affect the etching reaction on the surface of the wafer, makes the surface etching effect of the wafer more uniform, and improves the etching quality.

[0060] S4, using a robot to immerse a carrier containing a plurality of wafers to be etched into a chemical liquid at a set temperature for etching, and controlling the carrier containing a plurality of wafers to be etched to circulate in the etching tank.

[0061] The moving carrier 100 can avoid the heat generated during the etching reaction from accumulating in a local part of the chemical liquid, causing the temperature of the local part of the chemical liquid to rise rapidly and affecting the etching rate; moreover, the moving carrier 100 can make the chemical liquid flow fully, improve the uniformity of the concentration and temperature of the chemical liquid system, and be conducive to ensuring the stability of the etching rate of the wafer and obtaining good etching effect; the moving carrier 100 can also shake off the bubbles adsorbed on the surface of the wafer, avoid the bubbles from isolating the chemical liquid to affect the etching reaction on the surface of the wafer, make the surface etching effect of the wafer more uniform, and improve the etching quality.

[0062] Specifically, the circulation rate of the carrier 100 is 10-100 cm / min; if the movement rate is too slow, the chemical liquid cannot flow fully, which is not conducive to maintaining the uniformity of the concentration of the chemical liquid and dispersing the heat generated during the etching reaction; if the movement rate is too fast, the chemical liquid is easily splashed, which is dangerous.

[0063] S5, after etching for a set time, placing the etched wafer together with the carrier into the cleaning tank by the robot for cleaning.

[0064] The setting time is 1-20 min, and if the etching time is too short, the target film layer cannot be completely treated, affecting the photoelectric performance of the LED chip; if the etching time is too long, side etching, too large etching line width, damage to the bottom film layer and other problems are likely to occur, resulting in failure of the LED chip.

[0065] During cleaning, the mechanical hand holds the carrier 100 loaded with the etched wafer to shake and rotate in the deionized water, so as to clean the chemical liquid residues on the wafer surface.

[0066] In some embodiments, the use of a mechanical hand to immerse the carrier 100 loaded with a plurality of to-be-etched wafers in a chemical liquid reaching a set temperature for etching, and controlling the carrier 100 loaded with a plurality of to-be-etched wafers to circulate in the etching tank 300 includes:

[0067] The first mechanical hand is used to immerse the first carrier loaded with a plurality of to-be-etched wafers in a chemical liquid reaching a set temperature for etching, and the first carrier is on one side of the etching tank 300.

[0068] The second mechanical hand is used to immerse the second carrier loaded with a plurality of to-be-etched wafers in a chemical liquid reaching a set temperature for etching, and the second carrier is on the other side of the etching tank 300.

[0069] The first carrier and the second carrier maintain a relative position and circulate in the same direction at the same time.

[0070] Simultaneous etching of wafers on opposite sides of the etching tank 300 improves the utilization efficiency of the device while maintaining the stability of the chemical liquid temperature, and also improves the production efficiency.

[0071] Embodiment three:

[0072] Figure 3 A wet etching flowchart of the passivation layer of the GaN wafer in the embodiment of the application is shown, including the following steps:

[0073] S11, the GaN wafer on which the passivation layer is completed is placed on the carrier.

[0074] Here, taking 25 GaN wafers loaded in each carrier 100 as an example for illustration.

[0075] S12, add ordinary water in the water bath heating module, add BOE etching liquid in the etching tank, and add deionized water in the cleaning tank.

[0076] BOE etching solution is the existing, namely buffer oxide etching solution, which is prepared by dissolving NH4F and HF in water in a volume ratio of 2-20:1. Specifically, a 6:1 BOE etching solution is prepared by mixing 40% NH4F aqueous solution and 49% HF aqueous solution in a volume ratio of 6:1. Under the condition of constant temperature, the etching rate is about 10 nm per second. HF is the main etching solution, and NH4F is used as a buffer. The concentration of NH4F is fixed to maintain a certain etching rate.

[0077] If the concentration of HF in the BOE etching solution is too high, the etching rate of the passivation layer will be too fast, the etching process will be uncontrollable, the width of the etching line will be uncontrollable, and the film layer under the passivation layer will be damaged. If the concentration of HF in the BOE etching solution is too low, the etching time will be prolonged, which will affect the production efficiency.

[0078] S13, set the working temperature of the water bath heating module to 20℃, and start the wet etching device to preheat the ordinary water, the BOE etching solution and the deionized water.

[0079] The control accuracy of temperature is ±1℃, that is, the temperature of the BOE etching solution is controlled at 19-21℃, the etching rate is stable and controllable, and the etching effect of the passivation layer is good.

[0080] S14, after the ordinary water, the BOE etching solution and the deionized water reach 20℃, nitrogen gas is introduced into the etching tank.

[0081] Nitrogen is an inert gas, which is not soluble in BOE etching solution, does not react with BOE etching solution, and does not react with GaN sheet, and has low cost. The BOE etching solution is stirred with nitrogen, so that the temperature of the upper and lower layers is consistent. When etching the GaN sheet, it is beneficial to keep the etching rate of the whole GaN sheet consistent and obtain good etching effect. It can also carry away the bubbles adsorbed on the surface of the GaN sheet generated in the subsequent GaN sheet etching process, avoiding incomplete etching of the passivation layer of the GaN sheet.

[0082] S15, using a robot to immerse the carrier frame containing the GaN sheet to be etched into the BOE etching solution at 20℃ for etching, and controlling the carrier frame containing the GaN sheet to be etched to circulate in the etching tank.

[0083] The passivation layer of the GaN wafer will not only release heat during etching, but also produce SiF4 gas by the reaction of HF and SiO2, forming bubbles adsorbed on the GaN wafer. The circulation movement of the carrier 100 containing the GaN wafer to be etched in the etching tank 300 can shake off the bubbles adsorbed on the surface of the GaN wafer generated by the etching reaction, avoiding incomplete etching of the passivation layer of the GaN wafer. The circulation movement of the carrier 100 can also flow the BOE etching solution, which is beneficial to disperse the heat generated by the etching reaction, homogenize the concentration and temperature of the BOE etching solution, and keep the etching rate stable, so that the GaN wafer can obtain better etching effect.

[0084] The BOE etching solution is used once. After the number of GaN wafers etched by the BOE etching solution reaches a specified number, the old BOE etching solution is discharged and a new BOE etching solution is replaced.

[0085] S16, after etching for 10 minutes, the GaN wafer and the carrier are placed in the cleaning tank by the mechanical hand for cleaning.

[0086] After cleaning, the GaN wafer is spin-dried, and then it is checked under a microscope whether the passivation layer is etched clean and whether the etching line width meets the quality control requirements. The GaN wafer meeting the requirements can enter the next process.

[0087] The circulation movement of the carrier 100 containing the GaN wafer to be etched in the etching tank 300 can disperse the heat generated by the etching reaction of the passivation layer of the GaN wafer to the entire BOE etching solution system in time, avoid the rapid increase of the local temperature of the BOE etching solution, and keep the etching rate stable, so that the GaN wafer can obtain better etching effect. The circulation movement of the carrier 100 can also stir the BOE etching solution, flow the BOE etching solution in the etching tank, improve the temperature uniformity of the BOE etching solution, keep the etching rate stable, and make the passivation layer of the GaN wafer obtain better etching effect. The circulation movement of the carrier 100 can also flow the BOE etching solution in the etching tank by setting the gas inlet hole 310 below the etching tank to introduce nitrogen to stir the BOE etching solution, make the temperature of the BOE etching solution in the bottom layer and the upper layer of the etching tank 300 uniform, keep the etching rate of the GaN wafer consistent, and obtain good etching effect. The circulation movement of the carrier 100 can also control the temperature of the etching tank 300 by the water bath heating module 200 to 20±1℃, which can reduce the influence of the change of the environmental temperature on the temperature of the BOE etching solution, reduce the temperature fluctuation of the BOE etching solution, keep the temperature of the BOE etching solution stable, keep the etching rate stable, and make the GaN wafer obtain good etching effect.

[0088] The application provides a wet etching device and a wet etching method, heat generated by etching reaction is dispersed to the whole chemical liquid system in time by controlling the movement of the bearing frame 100 in the annular or loop-shaped etching tank 300 by a mechanical hand, local temperature of the chemical liquid is prevented from rapidly rising, etching rate is prevented from being too fast, and etching effect is affected; the chemical liquid can also be stirred, the chemical liquid is made to flow in the etching tank, temperature uniformity of the chemical liquid is improved, etching rate is kept stable, and better etching effect of the wafer is obtained; the gas is introduced into the gas inlet hole 310 arranged below the etching tank to stir the chemical liquid, temperature of the chemical liquid in the bottom layer and the upper layer of the etching tank 300 is uniform, etching rate of the whole wafer is kept consistent, and good etching effect is obtained; the etching tank 300 is controlled in temperature by the water bath heating module 200, the influence of environmental temperature change on the temperature of the chemical liquid is reduced, temperature fluctuation of the chemical liquid is reduced, the temperature of the chemical liquid is kept stable, the etching rate is kept stable, and good etching effect of the wafer is obtained.

[0089] The technical method of the application can efficiently conduct and disperse the heat generated by wafer etching reaction by using the bearing frame 100 made of metal and the good heat conductivity of the metal, heat accumulation in the bearing frame 100 is avoided, and etching rate of the wafer is affected.

[0090] The technical method of the application can also take away the bubbles adsorbed on the wafer surface generated by wafer surface etching reaction by introducing the protective gas, the bubbles are prevented from isolating the chemical liquid to affect the etching reaction on the wafer surface, the wafer surface etching effect is more uniform, and etching quality is improved.

[0091] The technical method of the application can also shake off the bubbles adsorbed on the wafer surface generated by wafer surface etching reaction by controlling the movement of the bearing frame 100 in the annular or loop-shaped etching tank 300 by the mechanical hand, the bubbles are prevented from isolating the chemical liquid to affect the etching reaction on the wafer surface, the wafer surface etching effect is more uniform, and etching quality is improved.

[0092] The technical method of the application can etch wafers on opposite sides of the etching tank 300 at the same time, the utilization efficiency of the device is improved while the temperature of the chemical liquid is kept stable, and production efficiency is also improved.

[0093] The technical method of the application is suitable for wet etching of various film layers on wafers, and can improve etching stability, such as wet etching of ITO film layers; and is also suitable for improving stability of wet etching using other chemical liquids, such as HCl and H2SO4.

[0094] The wet etching device and the wet etching method provided by the embodiment of the present application are described in detail above, and the principle and the implementation manner of the present application are described by using specific examples in this paper. The above description of the embodiments is only used to help understand the method of the present application and its core idea. Meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation manner and the application range will be changed, and the above description should not be understood as a limitation on the present application.

Claims

1. A wet etching method characterized by, The wet etching method is implemented based on a wet etching device; The wet etching device comprises a bearing frame, a mechanical hand, a water bath heating module, an etching tank and a cleaning tank, the water bath heating module surrounds the etching tank, the etching tank surrounds the cleaning tank; The bearing frame is used for loading wafer pieces to be etched, and the bearing frame is a corrosion-resistant metal bearing frame; The mechanical hand is used for grabbing and moving the bearing frame, and the mechanical hand is used for controlling the movement of the bearing frame in the etching tank; the mechanical hand has two; The water bath heating module is used for controlling the temperature of the etching tank; The etching tank is in a ring structure, the bottom of the etching tank is provided with a plurality of air inlet holes, the etching tank is used for containing chemical liquid, and the chemical liquid is used for etching wafer pieces; the interval between the plurality of air inlet holes is 1-5 cm; The cleaning tank is used for cleaning the etched wafer pieces; The wet etching method comprises the following steps: ordinary water is added in the water bath heating module, corresponding chemical liquid is added in the etching tank, and deionized water is added in the cleaning tank; The working temperature of the water bath heating module is set, and the wet etching device is started to preheat the ordinary water, the chemical liquid and the deionized water; After the ordinary water, the chemical liquid and the deionized water all reach the set temperature, protective gas is introduced into the etching tank; The bearing frame containing a plurality of wafer pieces to be etched is immersed into the chemical liquid at the set temperature by the mechanical hand for etching, and the bearing frame containing a plurality of wafer pieces to be etched is controlled to circulate in the etching tank; After etching for a set time, the etched wafer pieces are put into the cleaning tank together with the bearing frame by the mechanical hand for cleaning; The bearing frame containing a plurality of wafer pieces to be etched is immersed into the chemical liquid at the set temperature by the mechanical hand for etching, and the bearing frame containing a plurality of wafer pieces to be etched is controlled to circulate in the etching tank; The first bearing frame containing a plurality of wafer pieces to be etched is immersed into the chemical liquid at the set temperature by the first mechanical hand for etching, and the first bearing frame is on one side of the etching tank; The second bearing frame containing a plurality of wafer pieces to be etched is immersed into the chemical liquid at the set temperature by the second mechanical hand for etching, and the second bearing frame is on the other side of the etching tank; The first bearing frame and the second bearing frame keep relative positions and circulate in the same direction at the same time.

2. The wet etching method of claim 1, wherein, The circulation rate of the bearing frame is 10-100 cm / min.

3. The wet etching method of claim 1, wherein, The set time is 1-20 min.

4. The wet etching method of claim 1, wherein, The protective gas comprises one or more of nitrogen, helium and argon.

5. The wet etching method of claim 1, wherein, The flow rate of the protective gas is 0.5 to 10 cc / cm 2 .

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