TWI417693B - Etching apparatus and method of controlling the same - Google Patents

Description

Etching device and control method thereof

This invention relates to process equipment, and more particularly to an etching apparatus and method of controlling the same.

In the production process of the liquid crystal display panel, there is a process of etching the conductive metal or non-metal of the surface of the board irrespective of the line to preserve the line portion, and the current adopter is generally wet etching.

The principle of the wet etching technique is to use a chemical reaction between the etching solution and the film to be etched. First, the reactants in the etching solution will pass through a layer of a relatively thin boundary layer by diffusion effect to reach the surface of the film to be etched. After the etching process, the etching solution remaining on the plate must be blown off with a wind knife.

Due to the operation in a wet environment, the crystallization of the etching solution caused by the etching reaction will adhere to the edge of the air knife. Therefore, when the air is supplied, crystallization causes uneven wind pressure, and the photoresist of the conductive metal film on the surface of the sheet is easily removed, or the crystal completely blocks the edge of the air knife, and the cleaning of the etching liquid remaining on the sheet is reduced. The effect, which in turn leads to poor products, needs to be improved.

Therefore, the surface of the wind blade must be periodically removed. This cleaning operation is usually once a week, and the etching machine must be stopped, the air knife must be dismantled, and then the air knife should be removed to restart the etching. The machine requires about 2 to 3 people, and the time spent is 4-5 hours, which results in labor costs and affects production capacity.

Accordingly, one aspect of the present invention is to provide an etching apparatus and a control method therefor.

According to an embodiment of the invention, an etching apparatus includes an etching chamber, an etching solution storage tank, a cleaning device, and a conductivity monitoring device. The cleaning device has a wind knife, a first fluid line, a liquid pump and a first valve, wherein the air knife is disposed in the etching chamber, and one end of the first fluid line is connected to the air knife and communicates with the liquid pump In connection, in addition, the first valve is disposed on the first fluid line. The conductivity monitoring device is respectively coupled to the first valve and the etching liquid storage tank for monitoring the conductivity in the etching liquid storage tank and controlling the opening and closing of the first valve. Thereby, if the first valve is opened, the first fluid pipeline can introduce the water body of the liquid pump into the etching chamber to be provided with the air knife, thereby removing the crystal on the air knife, and no need to stop to manually clean the air knife.

According to another embodiment of the present invention, a method for controlling an etching apparatus, wherein the etching apparatus includes an etching chamber and an etching liquid storage tank, and when performing the control method, first detecting the conductivity of the etching liquid in the etching liquid storage tank When the conductivity is higher than a predetermined upper limit, the water body of a liquid pump is introduced into the etching chamber where a wind knife is provided, and then the water flowing into the etching chamber is introduced into the etching liquid storage tank. Therefore, when the conductivity of the etching liquid in the etching liquid storage tank is too high, the water body of the liquid pump can be used to clean the air knife first, and then flow into the etching liquid storage tank to reduce the concentration of the etching liquid, thereby achieving the effect of both.

The above description will be described in detail in the following embodiments, and further explanation of the technical solutions of the present invention will be provided.

In order to make the description of the present invention more complete and complete, reference is made to the accompanying drawings and the accompanying drawings. On the other hand, well-known elements and steps are not described in the embodiments to avoid unnecessarily limiting the invention.

In the scope of the embodiments and patent applications, unless the context specifically dictates the articles, "a" and "the" may mean a single or plural.

As used herein, "about," "about," or "substantially" is used to modify the amount of any slight change, but such minor changes do not alter the nature. In the embodiment, unless otherwise stated, the error range represented by "about", "about" or "substantially" is generally allowed to be within 20%, preferably 10%. Within, and more preferably within five percent.

Referring to FIG. 1, FIG. 1 is a schematic diagram of an etching apparatus 100 in accordance with an embodiment of the present invention. As shown in FIG. 1, the etching apparatus 100 includes an etching chamber 110, an etching solution storage tank 120, and a fluid conduit 150, wherein one end of the fluid conduit 150 is in communication with the etching chamber 110, and the other end is in communication with the etching liquid storage tank 120. .

The etchant storage tank 120 can store an etchant (eg, an aqueous solution of oxalic acid, an aqueous solution of hydrogen bromide, a mixed aqueous solution of hydrochloric acid and nitric acid, or other suitable solution, or a combination thereof). In order to supply the etching solution to the etching chamber 110 for a wet etching process, the etching apparatus 100 may include a pump 182, a fourth fluid line 183, and a nozzle 184, wherein the pump 180 is combined with the fourth fluid line 183, the fourth fluid One end of the conduit 183 is in communication with the etchant storage tank 120, and the other end of the fourth fluid conduit 183 is provided with a nozzle 184 and disposed in the etching chamber 110. In use, the pump 182 extracts the etching liquid in the etching solution storage tank 120 from one end of the fourth fluid line 183, and then sprays the etching liquid on the etching chamber 110 through the nozzle 184 at the other end of the fourth fluid line 183. Inside, in order to perform the wet etching process. In the wet etching process of the liquid crystal display panel, a transparent conductive layer on the substrate, such as a transparent conductive layer made of indium tin oxide, is covered with a mask layer, and the substrate is immersed in the etching liquid to remove the unmasked substrate. The layer covers the transparent conductive layer and defines a pixel electrode on the substrate.

The etching apparatus 100 also includes a cleaning device 130 to clean the etching chamber 110. The cleaning device 130 has an air knife 131, a first fluid line 132, a liquid pump 133, a first valve 134, and a third valve 136. Structurally, the air knife 131 is disposed in the etching chamber 110, and one end of the first fluid line 132 is connected and communicated with the air knife 131, and the other end of the first fluid line 132 is in communication with the liquid pump 133. The first valve 134 and the third valve 136 are disposed on the first fluid line 132.

At the time of use, the etching liquid remaining on the substrate is blown off by the air knife 131. For example, the air knife 131 has a narrow slit, and the slit can be a straight line. Therefore, when the air is blown, the wind pressure is blown out by the slit to form a wind curtain, and the substrate can pass through the air knife 131 in a vertical direction to blow off. Residual liquid.

However, during the wet etching process, it adheres to the edge of the air knife 131 due to the reaction of the etching liquid with the transparent conductive layer. Therefore, in the cleaning device 130, when the first valve 134 and the third valve 136 are opened, the first fluid line 132 can introduce the water body of the liquid pump 133 into the etching chamber 100 where the air knife 131 is provided, thereby The crystal on the air knife 131 is removed. Thereby, the air knife 131 is cleaned by human power without stopping the machine.

For example, the etching solution may be an aqueous solution of oxalic acid, but the reaction of oxalic acid with indium tin oxide generates indium oxalate crystals (In ₂ (C ₂ O ₄ ) ₃ ), which is sprayed on the air knife 131, causing the air knife 131 to block. Then, the air knife 131 is flushed by the water body of the liquid pump 133, and since the indium oxalate crystal is dissolved in the water, the water liquid is applied to dissolve it and be detached from the knife edge of the air knife 131.

In view of the chemical reaction of wet etching, the concentration of the etching solution has a great influence on the reaction rate. If the concentration is too high, the etching rate will be too fast, which will cause the undercut phenomenon to be formed in the pattern to be defined, which will affect the yield of subsequent processes. If the concentration of the etching solution is unstable, the etching reaction cannot be effectively controlled, and the quality of the pixel electrode is unstable and the yield is affected.

Therefore, the etching apparatus 100 also includes a conductivity monitoring device 140. By monitoring the conductivity of the etching solution, the concentration of the etching solution can be known. If the concentration of the etching solution is higher, the conductivity is relatively higher. The conductivity monitoring device 140 is coupled to the first valve 134 and the etchant storage tank 120 for monitoring the conductivity of the etchant in the etchant storage tank 120 and controlling the opening and closing of the first valve 134.

In the present embodiment, the first valve 134 is an automatic valve that is controlled by the conductivity monitoring device 140, and the third valve 136 can be a manual valve that is normally kept open. The third valve 136 is closed if the first valve 134 fails, the first fluid line 132 ruptures, or other abnormal condition occurs.

The first valve 134 can be opened if the conductivity monitoring device 140 detects that the conductivity is above a predetermined upper limit. Then, the first fluid line 132 can introduce the water body of the liquid pump 133 into the etching chamber 110 where the air knife 131 is disposed, thereby removing the crystal on the air knife 131, and the crystal will subsequently flow into the etching chamber 110, but Basically it will not affect the process. Next, the fluid conduit 150 introduces the water flowing into the etching chamber 110 into the etching solution storage tank 120. Therefore, when the conductivity of the etchant in the etchant storage tank 120 is too high, the water body of the liquid pump 133 can be used to clean the air knife 131 and then flow into the etchant storage tank 120 to reduce the concentration of the etchant. The effect.

In practice, the predetermined upper limit value described above may be any value ranging from 68 ms/cm to 85 ms/cm. If the conductivity of the etchant exceeds 85ms/cm, it means that the concentration of the etchant is too high. If the concentration is too high, the etch rate will be too fast, resulting in undercut on the pattern to be defined on the substrate.

In addition, the etching apparatus 100 may include an etchant replenishing pump 160, a second fluid line 162, a second valve 164, and a fourth valve 166. One end of the second fluid line 162 is in communication with the etchant storage 120, and the other end of the second fluid line 162 is in communication with the etchant replenishing pump 160. The second valve 164 and the fourth valve 166 are disposed on the second fluid line 162 , wherein the second valve 164 is coupled to the conductivity monitoring device 140 .

In the present embodiment, the second valve 164 is an automatic valve that is controlled by the conductivity monitoring device 140, and the fourth valve 166 can be a manual valve that is normally kept open. The fourth valve 166 is closed if the second valve 164 fails, the second fluid line 162 ruptures, or other abnormal conditions occur.

If the conductivity monitoring device 140 detects that the conductivity is below a predetermined lower limit, it can open the second valve 164 and close the first valve 134. The second fluid line 162 is then introduced into the etchant storage tank 120 by the etchant of the etchant replenishing pump 160. Therefore, when the conductivity of the etching liquid in the etching solution storage tank 120 is too low, the etching liquid replenishing pump 160 immediately fills the new etching liquid into the etching liquid storage tank 120 to increase the concentration of the etching liquid.

In practice, the predetermined lower limit value described above may be any value ranging from 44 ms/cm to 55 ms/cm. If the conductivity of the etching solution exceeds 55ms/cm, it means that the concentration of the etching solution is too low. If the concentration is too low, the etching rate will be too slow, which will lengthen the processing time and even make the pattern to be defined on the substrate difficult to form.

In addition, the higher the temperature of the etching solution, the faster the etching rate. If the temperature of the etching solution is not uniform during etching, the line width of each corner of the substrate is likely to be different. In order to avoid such a situation, the etching apparatus 100 may include a third fluid line 170, a control valve 171, a control valve 172, and a pump 173. Both ends of the third fluid line 170 are in communication with the etchant storage tank 120, the control valves 171, 172 are disposed on the third fluid line 170, and the pump 173 is coupled to the third fluid line 170.

When the control valves 171, 172 are opened, the pump 173 extracts the etching liquid in the etching solution storage tank 120 from one end of the third fluid line 170, and then returns the etching liquid from the other end of the third fluid line 170 to the etching. The liquid storage tank 120 thereby agitates the etching liquid of the etching liquid storage tank 120 to average the etching liquid temperature. This procedure is referred to herein as "temperature control small cycle".

Alternatively or additionally, in the etching apparatus 100, the etching liquid may be pumped into the etching chamber 110 through the fourth fluid line 183 and the nozzle 184 by the pump 182 at intervals, and then the etching liquid flows through the fluid conduit 150. The etchant storage tank 120 itself maintains the conduit through which the etchant flows to maintain a predetermined temperature. This procedure is referred to herein as a "temperature-controlled large cycle."

Please refer to FIG. 2, which is a block diagram of the conductivity monitoring device 140. As shown in FIG. 2, the conductivity monitoring device 140 includes a detecting unit 210, a main control unit 220, a conductivity detecting unit 230, a timing unit 240, a driving unit 250, and an automatic switching unit 260.

In order to avoid the etchant concentration being too high, the detecting unit 210 can detect the conductivity of the etchant of the etchant storage tank 120, and the conductivity detecting unit 230 can detect whether the conductivity is higher than a predetermined upper limit. When the electrical conductivity is higher than the predetermined upper limit value, the main control unit 220 may cause the timing unit 240 to calculate a liquid replenishment time and generate a liquid replenishment signal. The driving unit 250 can drive the automatic switching unit 260 based on the liquid replenishing time and the liquid replenishing signal, so that the automatic switching unit 260 turns off the second valve 164 to prevent the etching liquid of the etching liquid replenishing pump 160 from flowing into the etching liquid storage tank 120, and is in the liquid The first valve 134 is opened during the replenishment time to introduce the water body of the liquid pump 133 into the etching chamber 110 where the air knife 131 is provided.

In this way, a suitable period of time (ie, liquid replenishment time) required for the water to flow through the air knife 131 and then replenished into the etching solution storage tank 120 to make the concentration of the etching liquid moderate is estimated in advance, and then the water body is replenished at this time. Avoiding too much water to replenish the etchant concentration is too low.

On the other hand, the conductivity detecting unit 230 can detect whether the conductivity is lower than a predetermined lower limit value. When the conductivity is lower than the predetermined lower limit, the main control unit 220 may cause the timing unit 240 to calculate an etchant replenishment time and generate an etchant replenishment signal, and the driving unit 250 may replenish the signal based on the etchant replenishment time and the etchant. The automatic switching unit 260 is driven to cause the automatic switching unit 260 to close the first valve 134 to prevent the water body of the liquid pump 133 from being introduced into the etching chamber 110 where the air knife 131 is disposed, and to open the second valve during the etching liquid replenishing time. The 164 is introduced into the etching solution storage tank 120 by the etching liquid for the etching liquid replenishing pump 160.

In this way, an appropriate period of time (ie, etchant replenishment time) required to replenish the etchant solution to the etchant storage tank 120 is prepared in advance, and the etchant is replenished at this time to avoid the etchant. Too much replenishment causes the concentration of the etchant to be too high.

As described above, the detecting unit 210, the main control unit 220, the conductivity detecting unit 230, the timing unit 240, the driving unit 250, and the automatic switching unit 260, etc., may be a soft body, a hardware body, and/or a body. For example, if the execution speed and accuracy are the primary considerations, the units can basically be dominated by hardware and/or carcass; if design flexibility is the primary consideration, then these units are basically optional software. Mainly; or, these units can work together in software, hardware and carcass. It should be understood that the above examples are not intended to limit the present invention, and are not intended to limit the present invention. Those skilled in the art will be able to flexibly select the specific embodiments of the units as needed.

In addition, those skilled in the art can understand that the above-mentioned units are named according to the functions they perform, only to make the technology of the present invention more obvious and understandable, and not to limit such units. It is still an embodiment of the present disclosure to integrate each unit into the same unit or split into multiple units, or to change the function of any unit to another unit.

Please refer to FIG. 3, which is a flow chart of a method for controlling an etching apparatus according to another embodiment of the present invention. As shown in FIG. 3, the control method includes steps 310-350 (it should be understood that the steps mentioned in this embodiment can be adjusted according to actual needs, unless otherwise specified. It can even be executed simultaneously or partially).

In step 310, it is detected whether the conductivity of the etching solution in the etching solution storage tank is higher than a predetermined upper limit value or lower than a predetermined lower limit value. When the conductivity is higher than the predetermined upper limit, the water body of a liquid pump is introduced into the etching chamber to provide a wind knife in step 330, and then the water body flowing into the etching chamber is introduced into the etching liquid storage tank. Therefore, when the conductivity of the etchant in the etchant storage tank 120 is too high, the water body of the liquid pump 133 can be used to clean the air knife 131 and then flow into the etchant storage tank 120 to reduce the concentration of the etchant. The effect.

Furthermore, in step 330, when the conductivity is higher than the predetermined upper limit value, a liquid replenishment time is calculated, and the water body of the liquid pump 133 is introduced into the etching chamber 110 where the air knife 131 is provided in the liquid replenishing time. And preventing the etching liquid of the etching liquid replenishing pump 160 from flowing into the etching liquid storage tank 120. In this way, a suitable period of time (ie, liquid replenishment time) required for the water to flow through the air knife 131 and then replenished into the etching solution storage tank 120 to make the concentration of the etching liquid moderate is estimated in advance, and then the water body is replenished at this time. Avoiding too much water to replenish the etchant concentration is too low.

On the other hand, when the conductivity is lower than the predetermined lower limit value, an etching solution for an etching liquid replenishing pump is introduced into the etching liquid storage tank in step 350. Thereby, when the conductivity of the etching liquid in the etching solution storage tank 120 is too low, the new etching liquid is immediately added to the etching liquid storage tank 120, so that the concentration of the etching liquid is increased.

Furthermore, in step 350, when the conductivity is lower than the predetermined lower limit value, an etching liquid replenishing time is calculated, and the etching liquid of the etching liquid replenishing pump 160 is introduced into the etching liquid storage tank 120 in the etching liquid replenishing time, and is prevented. The water body of the liquid pump 133 is introduced into the etching chamber 110 where the air knife 131 is provided. In this way, an appropriate period of time (ie, etchant replenishment time) required for the etchant to be replenished to the etchant storage tank 120 is estimated in advance, and the etchant is replenished at this time to avoid etching. Too much liquid is added, which causes the concentration of the etching solution to be too high.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and the present invention can be modified and modified without departing from the spirit and scope of the present invention. The scope is subject to the definition of the scope of the patent application attached.

100. . . Etching equipment

170. . . Third fluid line

110. . . Etching chamber

120. . . Etching solution storage tank

130. . . Cleaning device

131. . . Air knife

132. . . First fluid line

133. . . Liquid pump

134. . . First valve

136. . . Third valve

140. . . Conductivity monitoring device

150. . . Fluid conduit

160. . . Etching solution replenishing pump

162. . . Second fluid line

164. . . Second valve

166. . . Fourth valve

171. . . Control valve

172. . . Control valve

173. . . Pump

182. . . Pump

183. . . Fourth fluid line

184. . . nozzle

210. . . Detection unit

220. . . Main control unit

230. . . Conductivity detection unit

240. . . Timing unit

250. . . Drive unit

260. . . Automatic switching unit

310-350. . . step

The above and other objects, features, advantages and embodiments of the present invention will become more apparent and understood.

1 is a schematic view of an etching apparatus in accordance with an embodiment of the present invention;

Figure 2 is a block diagram of the conductivity monitoring device of Figure 1;

3 is a flow chart of a method of controlling an etching apparatus in accordance with another embodiment of the present invention.

100. . . Etching equipment

110. . . Etching chamber

120. . . Etching solution storage tank

130. . . Cleaning device

131. . . Air knife

132. . . First fluid line

133. . . Liquid pump

134. . . First valve

136. . . Third valve

140. . . Conductivity monitoring device

150. . . Fluid conduit

160. . . Etching solution replenishing pump

162. . . Second fluid line

164. . . Second valve

166. . . Fourth valve

170. . . Third fluid line

171. . . Control valve

172. . . Control valve

173. . . Pump

182. . . Pump

183. . . Fourth fluid line

184. . . nozzle

Claims (10)

An etching apparatus comprising: an etching chamber; an etching liquid storage tank; a cleaning device having a wind knife, a first fluid line, a liquid pump, and a first valve, wherein the air knife is disposed on the etching Inside the chamber, one end of the first fluid line is connected to the air knife and communicated with the other end, and the other end is connected to the liquid pump; further, the first valve is disposed on the first fluid line; and a conductivity The monitoring device is coupled to the first valve and the etching liquid storage tank for monitoring the conductivity in the etching liquid storage tank and controlling the opening and closing of the first valve. The etching apparatus of claim 1, further comprising: a fluid conduit having one end in communication with the etching chamber and the other end in communication with the etching liquid storage tank. The etching apparatus of claim 2, further comprising: an etchant replenishing pump; a second fluid line having one end connected to the etchant storage tank and the other end being in communication with the etchant replenishing pump; The second valve is disposed on the second fluid pipeline and coupled to the conductivity monitoring device. The etching apparatus of claim 3, wherein the conductivity monitoring device comprises: a timing unit; an automatic switching unit; a detecting unit for detecting the conductivity; and a conductivity detecting unit for detecting the Whether the electrical conductivity is higher than a predetermined upper limit value or lower than a predetermined lower limit value; a main control unit for controlling the timing unit and generating a supplementary signal, wherein when the electrical conductivity is higher than the predetermined upper limit value Having the timing unit calculate a liquid replenishment time and generate a liquid replenishment signal; and when the conductivity is lower than the predetermined lower limit value, the timing unit calculates an etchant replenishment time and generates an etchant replenishment signal And a driving unit, wherein the automatic switching unit is driven by the supplementary signal of the main control unit, wherein the automatic switching unit turns off the second valve when the liquid replenishes the signal, and the liquid replenishing time The first valve is opened internally; when the etching liquid replenishes the signal, the automatic switching unit is closed to the first valve, and the second valve is opened during the etching liquid replenishing time. The etching apparatus of claim 4, wherein the automatic switching unit closes the first and second valves when the conductivity is between the predetermined upper limit value and the predetermined lower limit value. The etching apparatus of claim 5, wherein the predetermined lower limit value is 55 ms/cm, and the predetermined upper limit value is 85 ms/cm. A control method for an etching apparatus, wherein the etching apparatus comprises an etching chamber and an etching liquid storage tank, the control method comprising: (a) detecting a conductivity of the etching liquid in the etching liquid storage tank; (b) when the When the conductivity is higher than a predetermined upper limit value, a water body of a liquid pump is introduced into the etching chamber where a wind knife is provided; and (c) a water body flowing into the etching chamber is introduced into the etching liquid storage tank. . The control method of claim 7, further comprising: (d) introducing an etching solution of an etching solution replenishing pump into the etching solution storage tank when the conductivity is lower than a predetermined lower limit value. The control method of claim 8, wherein the step (b) comprises: calculating a liquid replenishment time when the conductivity is higher than the predetermined upper limit; and introducing the water body of the liquid pump in the liquid replenishment time The air knife is disposed in the etching chamber, and the etching liquid of the etching liquid replenishing pump is prevented from flowing into the etching liquid storage tank. The control method according to claim 8, wherein the step (d) comprises: calculating an etching solution when the conductivity is lower than the predetermined lower limit value And introducing the etching solution of the etching liquid replenishing pump into the etching liquid storage tank during the etching liquid replenishing time, and preventing the water body of the liquid pump from being introduced into the etching chamber where the air knife is disposed.