KR20080011905A - Wet cleaning apparatus and method - Google Patents

Abstract

A wet cleaning apparatus is provided to prevent a substrate from being distorted and avoid damage to the substrate by preventing bubbles from remaining in a cleaning solution. A process bath(110) has an inner space filled with a cleaning solution wherein a substrate is put into the space and is to be cleaned in the space. A mixture receptacle receives process solutions from a process solution supplying lines and mixes the supplied process solutions to generate a cleaning solution. A cleaning solution supplying line supply the cleaning solution in the mixture receptacle to the process bath. A circulation line can circulate the cleaning solution in the process bath. A bubble removing member can remove the bubbles in the cleaning solution circulated along the circulation line, installed in the circulation line.

Description

Wet cleaning apparatus and method {WET CLEANING APPARATUS AND METHOD}

1 is a block diagram of a wet cleaning apparatus according to the present invention.

FIG. 2 is a flowchart illustrating a process of the wet cleaning apparatus shown in FIG. 1.

3A to 3D are views for explaining a process of the wet cleaning apparatus according to the present invention.

* Protection statement for the main part of the drawing *

100: wet cleaning device

110: treatment tank

120: treatment liquid supply member

130: circulation member

The present invention relates to a wet cleaning apparatus and a method, and more particularly, to a device and method for cleaning a semiconductor substrate by immersing the semiconductor substrate in the generated cleaning liquid after mixing a plurality of processing liquids to produce a cleaning liquid.

In general, in the semiconductor manufacturing process, a cleaning process for removing various foreign matters such as particulate metal impurities, organic contaminants, and surface coating on the wafer is performed. Among these, the wet cleaning apparatus cleans the wafer by dipping the wafer into a bath containing a cleaning liquid.

A general wet cleaning apparatus has a treatment tank, a treatment liquid supply member, and a circulation member. The treatment tank has a space in which the cleaning liquid is filled. In addition, the treatment tank has a space in which the semiconductor substrate is immersed in the process to perform the cleaning process. The treatment liquid supply member supplies a plurality of treatment liquids to the treatment tank. Here, the processing liquids are liquids for generating a cleaning liquid for cleaning the substrate. For example, in the case of cleaning the substrate using SPM (Sulfuric Peroxide Mixture, or Piranha), which is a cleaning solution generally used to remove organic contaminants remaining on the semiconductor substrate, the treatment liquid supply member may include the treatment. Sulfuric acid (H 2 SO 4), hydrogen peroxide (H 2 O 2), and ultrapure water, respectively, are fed to the treatment tank in a predetermined mixing ratio. The circulation member circulates and mixes the treatment liquids supplied to the treatment tank. The circulation member has a circulation line in which a pump, a densitometer, and the like are installed, and the circulation line circulates the treatment liquids in the treatment tank to mix the treatment liquids described above.

In the above-described wet cleaning apparatus, as the process proceeds, the cleaning liquid in the treatment tank is gradually contaminated. Therefore, when the wafer cleaning process is performed for a predetermined period, a process of replacing the contaminated cleaning liquid with a new cleaning liquid is performed. The replacement of the cleaning liquid drains all the contaminated cleaning liquid remaining in the treatment tank, and after the treatment liquid supply member supplies the treatment liquids to the treatment tank, the circulation member circulates the treatment liquids in the treatment tank to generate the cleaning liquid. At this time, if the generated cleaning liquid satisfies the predetermined concentration and temperature conditions, the substrate is immersed in the treatment tank to resume the wet cleaning process.

However, the above-described wet cleaning apparatus generates a large amount of bubbles due to the chemical reaction of the processing liquids when the processing liquids are mixed. That is, when sulfuric acid, hydrogen peroxide, and ultrapure water are mixed, a large amount of bubbles are generated in addition to the exothermic phenomenon due to the chemical reaction of the treatment liquids. If such bubbles are generated in a large amount in the treatment tank, the wafers placed in the treatment tank may be displaced during the cleaning process to damage the wafer, and the cleaning liquid in which a large amount of bubbles remain is inefficient for cleaning the wafer.

In addition, when a large amount of bubbles are generated, the level of the cleaning liquid in the treatment tank becomes unstable, and the cleaning liquid is scattered to the outside of the treatment tank during the process, thereby degrading stability to the working environment of the facility.

In order to solve the above problems, an object of the present invention is to provide a wet cleaning apparatus and method for improving the cleaning efficiency of a substrate.

It is also an object of the present invention to provide a wet cleaning apparatus and method for reducing bubbles generated due to mixing of processing liquids inside a treatment tank.

It is also an object of the present invention to provide a wet cleaning apparatus and method for improving the stability of the working environment.

The wet cleaning apparatus according to the present invention for achieving the above object has a space filled with the cleaning liquid therein, and the processing tank, processing liquid supply lines for providing a space in which the substrate is immersed in the process to clean the substrate A mixing vessel receiving the treatment liquids, mixing the supplied treatment liquids to generate a cleaning liquid, and a cleaning liquid supply line for supplying the cleaning liquid in the mixing container to the treatment tank.

According to an embodiment of the present invention, the wet cleaning device further includes a circulation line for circulating the cleaning liquid in the treatment tank and a bubble removing member installed on the circulation line to remove bubbles in the cleaning liquid circulated along the circulation line. Include.

According to an embodiment of the present invention, the wet cleaning device is installed in the circulation line, the pressure member for pumping the cleaning liquid in the circulation line and the circulation line is installed in the circulation line, the circulation line due to the pumping of the pressure member It further includes a damper for maintaining a constant supply pressure change of the internal cleaning liquid.

In the wet cleaning method according to the present invention for achieving the above object, the substrate is immersed in a treatment tank filled with a cleaning liquid to clean the substrate, and the cleaning liquid is supplied to the treatment tank by mixing a plurality of treatment liquids to generate the cleaning liquid. After waiting for a predetermined time, the generated washing liquid is supplied to the treatment tank.

According to an embodiment of the present invention, the predetermined time is a time until bubbles generated when mixing a number of treatment liquids are reduced to an allowable value or less, and the wet cleaning method circulates the new cleaning liquid supplied to the pretreatment tank. Secondary bubbles remaining in the cleaning liquid are removed.

In the wet cleaning method according to the present invention for achieving the above object, if the cleaning liquid in the processing tank filled with the cleaning liquid is used more than a predetermined number of times, draining the cleaning liquid in the processing tank, mixing a plurality of processing liquids Generating a new cleaning liquid, waiting for a predetermined time to reduce bubbles remaining in the new cleaning liquid, and then supplying the cleaning liquid to the treatment tank, and circulating the new cleaning liquid supplied to the treatment tank to remove bubbles remaining in the new cleaning liquid. Removing the substrate by immersing the substrate in the cleaning liquid in the treatment tank.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed subject matter is thorough and complete, and that the spirit of the present invention to those skilled in the art will fully convey.

In addition, although the embodiment according to the present invention has been described with an example of a semiconductor manufacturing apparatus for cleaning a wafer by immersing it in a cleaning liquid, the present invention provides a substrate and a flat panel display for manufacturing a semiconductor integrated circuit chip with a predetermined processing liquid. It is applicable to all substrate processing apparatuses for processing glass substrates and the like.

(Example)

1 is a block diagram of a wet cleaning apparatus according to the present invention. Referring to FIG. 1, the wet cleaning apparatus 100 according to the present invention includes a treatment tank 110, a circulation member 120, a drain member 130, a treatment liquid supply member 140, a mixing member 150, and The controller 160 is included. The treatment tank 110 provides a space therein for performing a substrate treatment process. Here, the substrate treating step is a step of removing foreign matter remaining on the substrate surface. The treatment tank 110 has an inner tank 112 and an outer tank 114. The inner tank 112 has a space in which the cleaning liquid is filled during the process. The space has a volume in which a plurality of substrates W can be sufficiently immersed in the process. The outer tub 114 is installed to surround the inner tub 112 outside the inner tub 112. The outer tub 114 has a space in which the cleaning liquid is filled. The outer tub 114 receives the cleaning liquid overflowing from the inner tub 112 during the process. The outer tub 114 is open at the top, and the open top is used as a substrate entrance through which the substrate W enters and exits during the process. The open upper portion of the outer tub 114 may be opened and closed by an opening and closing member (not shown).

The circulation member 120 circulates the cleaning liquid in the treatment tank 110. The circulation member 120 includes a recycle line 121, a pressure member 123, a damper 124, a heater 125, a filter member 127, and a bubble removing member. 129. The circulation line 121 circulates the cleaning liquid in the treatment tank 110. The circulation line 121 circulates the cleaning liquid from the outer tank 114 to the inner tank 112, or from the inner tank 112 and the outer tank 114 to the inner tank 112.

The pressing member 123 is installed on the circulation line 121. The pressurizing member 125 provides a flow pressure to the cleaning liquid in the circulation line 121 so that the cleaning liquid is circulated along the circulation line 121. A pump is used as the pressurizing member 123. The damper 124 is installed at the rear end of the pressing member 123 on the circulation line 121. The damper 124 keeps the pressure fluctuation of the cleaning liquid constant due to the pumping of the pressing member 123 during the process. Accordingly, the damper 124 may prevent bubbles from being generated by the pumping of the pressing member 123 when the cleaning liquid circulated along the circulation line 121 passes through the pressing member 123.

The heater 125 heats the cleaning liquid circulated along the circulation line 121 to a predetermined process temperature. The process temperature is approximately 90 ° C to 120 ° C. At least one heater is used as the heater 125. The filter member 127 filters contaminants such as particles remaining in the cleaning liquid flowing along the circulation line 121. At least one filter is used as the filter member 127. The bubble removing member 129 removes bubbles remaining in the cleaning liquid circulated along the circulation line 121. At least one bubble removing member 129 is installed on the circulation line 121.

The drain member 130 drains the cleaning liquid in the treatment tank 110. The drain member 130 has a first drain line 132 and a second drain line 134. The first drain line 132 drains the washing liquid in the inner tank 112, and the second drain line 134 drains the washing liquid in the outer tank 114. The drain member 130 is provided to drain the cleaning liquid used in the existing treatment tank 110 when the cleaning liquid in the treatment tank 110 is replaced with a new cleaning liquid.

The treatment liquid supply member 140 includes a first chemical liquid supply member 142, a second chemical liquid supply member 144, and an ultrapure water supply member 146. The first chemical liquid supply member 142 has a first chemical liquid supply source 142a and a first chemical liquid supply line 142b. The first chemical liquid supply source 142a receives the first chemical liquid, and the first chemical liquid supply line 142b supplies the first chemical liquid from the first chemical liquid supply source 142a to the mixing member 150. The second chemical liquid supply member 144 has a second chemical liquid supply source 144a and a second chemical liquid supply line 144b. The second chemical liquid supply source 144a receives the second chemical liquid, and the second chemical liquid supply line 144b supplies the second chemical liquid from the second chemical liquid supply source 144a to the mixing member 150. The ultrapure water supply member 146 has an ultrapure water supply source 146a and an ultrapure water supply line 146b. The ultrapure water source 146a receives ultrapure water (DIW), and the ultrapure water supply line 146b supplies ultrapure water from the ultrapure water source 146a to the mixing member 150.

Here, each of the first chemical liquid supply member 142, the second chemical liquid supply member 144, and the ultrapure water supply member 146 may have a first chemical liquid, a second chemical liquid, and a liquid for preparing a cleaning liquid having a predetermined concentration during the process. The first and second chemical liquids and ultrapure water are supplied to the mixing member 150 by the mixing ratio of the ultrapure water. For example, in the case of preparing a SPM (Sulfuric Peroxide Mixture, or Piranha) solution as a cleaning solution, the first chemical solution is sulfuric acid (H 2 SO 4) solution, and the second chemical solution is hydrogen peroxide (H 2 O 2). In this case, SPM is usually 4: 1 in the ratio of sulfuric acid solution and hydrogen peroxide solution. Therefore, during the process, each of the first chemical supply member 142 and the second chemical supply member 144 supplies the first chemical and the second chemical at a feed ratio of 4: 1. In addition, the ultrapure water supply member 146 adjusts the supply amount of ultrapure water according to the concentration of SPM solution required in the process.

The mixing member 150 receives and mixes the first chemical liquid, the second chemical liquid, and the ultrapure water from the treatment liquid supply member 140. The mixing member 150 includes a mixing container 152 and a cleaning liquid supply line 154. The mixing container 152 has a space for firstly mixing the first chemical liquid, the second chemical liquid, and the ultrapure water to generate a cleaning liquid. That is, the mixing container 152 receives the first and second chemical liquids and ultrapure water from the processing liquid supply member 140 by a predetermined supply amount, and mixes them. The treatment liquids supplied to the mixing vessel 152 are mixed with each other to form a cleaning liquid and then stand by. At this time, the mixing vessel 152 may generate a large amount of bubbles (bubble) due to the chemical reaction of the treatment liquids. The mixing container 152 waits for a predetermined time after the cleaning solution is generated to reduce the bubbles.

Here, means for forcibly mixing the processing liquids in the mixing vessel 152 may be added to the mixing vessel 152. For example, the mixing vessel 152 is provided with a circulation pipe (not shown) and a pump (not shown) installed in the circulation pipe, and circulates the treatment liquid in the mixing container 152 along the circulation pipe while treating the treatment liquid. Can be mixed. Alternatively, the mixing vessel 152 may be provided with an agitator to mix the treatment liquids in the mixing vessel 152. Means for mixing the treatment liquids supplied by the mixing vessel 152 may be applied in various ways, it is not limited to the above-described mixing means.

The cleaning liquid supply line 154 supplies the cleaning liquid from the mixing container 152 to the treatment tank 110. The cleaning solution supply line 154 supplies the cleaning solution generated inside the mixing vessel 152 to the inner tank 112 of the treatment tank 110. Alternatively, the cleaning liquid supply line 154 may supply the cleaning liquid from the mixing vessel 152 to the outer tank 114, or may simultaneously supply the washing liquid to the inner tank 112 and the outer tank 114.

The controller 160 controls the wet cleaning apparatus 100. That is, the controller 160 opens and closes the valves V1 and V2 and drives the pressurizing member 123 to circulate the cleaning liquid in the treatment tank 110. The controller 160 controls the opening and closing of the valves V3 and V4 to control the drainage of the cleaning liquid in the treatment tank 110. The controller 160 controls opening and closing of the valves V5, V6, and V7 to control supply of the first and second chemical liquids and the ultrapure water of the mixing member 150. Then, the controller 160 controls the opening and closing of the valve V8 to control the supply of the cleaning liquid from the mixing member 150 to the processing tank 110. In addition, the controller 160 controls the transfer and conveyance of the substrate W during the process.

Hereinafter, the process of the wet cleaning apparatus 100 having the above-described configuration will be described in detail. Here, the reference numerals for the above-described components are the same, and the detailed description of the components is omitted.

2 is a flowchart illustrating a process of the wet cleaning apparatus illustrated in FIG. 1, and FIGS. 3A to 3D are diagrams for describing a process of the wet cleaning apparatus according to the present invention.

Referring to FIG. 2, when the process of the wet cleaning apparatus 100 is started, the mixing member 150 receives the first chemical liquid, the second chemical liquid, and the ultrapure water from the treatment liquid supply member 140 to mix the treatment tank. Supply to (110). When the cleaning liquid is supplied to the treatment tank 110 by a predetermined level, the circulation member 120 circulates the cleaning liquid in the treatment tank 110 to satisfy the predetermined process condition of the cleaning liquid in the treatment tank 110. When the cleaning liquid in the processing tank 110 satisfies the process conditions, the wet cleaning apparatus 100 performs a process of immersing the substrate W in the processing tank 110 to remove foreign substances remaining on the surface of the substrate (S110). ).

When the above-described substrate treatment process is repeatedly performed, the cleaning liquid in the treatment tank 110 is gradually contaminated, so the cleaning liquid in the treatment tank 110 needs to be replaced. That is, the controller 160 determines whether the above-described substrate processing process is performed more than a predetermined number of times during the substrate processing process (120). In the present embodiment, the control unit 160 performs the substrate processing process more than a predetermined number of times.

If the substrate treatment process proceeds more than a predetermined number of times, the wet cleaning apparatus 100 performs a process of replacing the cleaning liquid in the treatment tank 110 (S130). The process of replacing the cleaning liquid in the treatment tank 110 is as follows.

 If the process proceeds for more than a predetermined time, the cleaning process of the substrate is stopped, and the cleaning liquid in the treatment tank 110 is drained (S132). That is, referring to FIG. 3A, the controller 160 opens the valves V3 and V4, and the first and second drain lines 132 and 134 of the drain member 130 are used in the treatment tank 110. The washing liquid is drained to the outside of the treatment tank 110 (S132).

In the process of draining the cleaning liquid in the processing tank 110, the mixing member 150 mixes the processing liquids supplied from the processing liquid supply member 140 to generate the cleaning liquid, and then generates the generated cleaning liquid into the processing tank 110. Supply (S134). That is, the controller 160 opens the valves V5, V6, and V7, and each of the first chemical liquid supply line 142, the second chemical liquid supply line 144, and the ultrapure water supply line 146 is a mixing vessel 152. ), The first chemical liquid, the second chemical liquid, and ultrapure water are supplied by a predetermined supply amount. The first chemical liquid, the second chemical liquid, and the ultrapure water supplied to the mixing vessel 152 are primarily mixed to generate a cleaning liquid. Here, a large amount of bubbles are generated in the mixing vessel 152 due to the mixing of the treatment liquids. The mixing vessel 152 waits the mixed liquid for a certain time so that the bubbles generated are reduced. The predetermined time is the time until bubbles generated due to the mixing of the treatment liquids are reduced below the allowable value. Therefore, the mixing member 150 reduces the bubbles generated during the mixing of the processing liquids and then supplies them to the processing tank 110.

At this time, when all the cleaning liquid in the treatment tank 110 is drained, the mixing member 150 supplies the cleaning liquid to the treatment tank 110. That is, referring to FIG. 3B, the controller 160 closes the valves V3, V4, V5, V6, and V7, and opens the valve V8. Therefore, the cleaning liquid supply line 154 supplies the cleaning liquid from the mixing vessel 152 to the treatment tank 110.

When the cleaning liquid in the treatment tank 110 is filled to a predetermined level or more, the circulation member 120 circulates the cleaning liquid in the treatment tank 110. That is, referring to FIG. 3C, the controller 160 closes the valve V8, opens the valves V1 and V2, and operates the pressing member 123. Accordingly, the circulation line 121 circulates the cleaning from the outer tank 114 to the inner tank 112. At this time, the damper 124 to change the pressure change in the circulation line 121 by the pumping of the pressure member 123. The heater 125 heats the cleaning liquid circulated along the circulation line 121 to a predetermined process temperature, and the filter member 127 filters contaminants in the cleaning liquid circulated along the circulation line 121. The bubble removing member 129 removes bubbles remaining in the cleaning liquid circulated along the circulation line 121. When the circulation member 120 circulates the cleaning liquid in the processing tank 110 for a predetermined time, the plurality of substrates W are immersed in the processing tank 110 to clean foreign substances remaining on the surface of the substrate. In addition, referring to FIG. 3D, when a substrate cleaning process is performed for a predetermined process time, the substrates W having been cleaned are removed from the treatment tank 110 and then transferred to a facility where a subsequent process is performed.

In the above-described wet cleaning apparatus 100 and the method, when the cleaning liquid in the treatment tank 110 is replaced, the plurality of treatment liquids are primarily mixed, and the bubbles generated at this time are reduced and then supplied to the treatment tank 110. In addition, the cleaning liquid supplied to the treatment tank 110 is circulated by the circulation member 120 to remove bubbles. Accordingly, the wet cleaning apparatus 110 and the method according to the present invention prevent the bubbles from remaining in the cleaning liquid in the treatment tank 110, thereby preventing the cleaning efficiency from being lowered during the substrate treatment process.

In addition, the wet cleaning apparatus 100 and the method according to the present invention can prevent the bubbles in the cleaning liquid from remaining in the substrate processing process, so that the cleaning liquid is sprayed onto the wafers W positioned in the conventional treatment tank 110. In this case, the bubbles in the cleaning liquid to be sprayed prevent the wafer W from being damaged by being displaced.

In addition, the wet cleaning apparatus 100 and the method according to the present invention can prevent bubbles in the cleaning liquid from remaining in the substrate treating process, thereby preventing the level of the cleaning liquid in the treatment tank 110 from becoming unstable. Therefore, the cleaning liquid is prevented from being scattered to the outside of the processing tank 110 during the substrate processing process, thereby improving the stability of the facility working environment.

The foregoing detailed description illustrates the present invention. In addition, the foregoing description merely shows and describes preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, changes or modifications may be made within the scope of the concept of the invention disclosed in this specification, the scope equivalent to the disclosed contents, and / or the skill or knowledge in the art. The above-described embodiments are for explaining the best state in carrying out the present invention, the use of other inventions such as the present invention in other state known in the art, and the specific fields of application and uses of the present invention. Various changes are also possible. Accordingly, the detailed description of the invention is not intended to limit the invention to the disclosed embodiments. Also, the appended claims should be construed to include other embodiments.

As mentioned above, the wet cleaning apparatus and method according to the present invention improve the cleaning efficiency of the substrate. In particular, the wet cleaning apparatus and method according to the present invention prevents the cleaning efficiency from being lowered due to bubbles remaining in the cleaning liquid.

In addition, the wet cleaning apparatus and method according to the present invention prevents bubbles in the cleaning liquid from remaining during the process, thereby preventing the substrate from being damaged due to bubbles in the cleaning liquid injected into the substrate during the substrate processing process. .

In addition, the wet cleaning apparatus and method according to the present invention can prevent bubbles in the cleaning liquid from remaining during the process, thereby preventing the cleaning liquid from being scattered from the processing tank due to unstable water level in the processing tank during the process. Thus, the stability of the working environment of the device is improved.

Claims (6)

In the wet cleaning apparatus, A treatment tank having a space filled with a cleaning liquid therein and providing a space in which the substrate is immersed in the process to clean the substrate, A mixing vessel receiving treatment liquids from the treatment liquid supply lines and mixing the supplied treatment liquids to generate a cleaning liquid, and And a cleaning solution supply line for supplying the cleaning solution in the mixing vessel to the treatment tank. The method of claim 1, The wet cleaning device, A circulation line for circulating the cleaning liquid in the treatment tank; And a bubble removing member installed on the circulation line to remove bubbles in the cleaning liquid circulated along the circulation line. The method of claim 1, The wet cleaning device, A pressure member installed in the circulation line and pumping the cleaning liquid in the circulation line to circulate; And a damper installed in the circulation line to maintain a constant change in the supply pressure of the cleaning liquid in the circulation line due to the pumping of the pressure member. The substrate is immersed in a treatment tank filled with a cleaning liquid to clean the substrate. The cleaning liquid is supplied to the treatment tank by mixing a plurality of treatment liquids, generating the cleaning liquid, and waiting for a predetermined time, and then supplying the generated cleaning liquid to the treatment tank. Wet cleaning method characterized in that. The method of claim 4, wherein The predetermined time is, Is the time until bubbles generated when mixing a plurality of treatment liquids are reduced below an allowable value, The wet cleaning method, Wet cleaning method characterized in that the secondary bubbles are removed in the cleaning liquid while circulating a new cleaning liquid supplied to the treatment tank. In the method by which a board | substrate is immersed in the processing tank filled with a washing | cleaning liquid, and wash | cleaned, When the cleaning liquid in the treatment tank is used more than a predetermined number of times, draining the cleaning liquid in the treatment tank; Mixing a plurality of treatment liquids to form a new cleaning liquid, waiting for a predetermined time to reduce bubbles remaining in the generated new cleaning liquid, and then supplying the treatment liquid to the treatment tank; Circulating a fresh cleaning solution supplied to the treatment tank to remove bubbles remaining in the fresh cleaning solution; Wet cleaning method comprising the step of controlling the substrate by immersing the substrate in the cleaning liquid in the treatment tank.

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