CN210607200U - Wafer cleaning device and wafer cleaning system - Google Patents

Abstract

The utility model relates to a wafer cleaning device and wafer cleaning system can optimize the effect of getting rid of the particle at the wafer back to improve the yield of wafer production. The wafer cleaning device comprises a cleaning brush and a sprayer, wherein the cleaning brush is used for cleaning impurities on the back of a wafer to be cleaned, the sprayer can spray cleaning liquid towards the wafer, and the cleaning liquid is conductive and can release charges on the back of the wafer.

Description

Wafer cleaning device and wafer cleaning system

Technical Field

The utility model relates to a clean field of wafer, concretely relates to clean system of wafer cleaning device and wafer.

Background

In the production and manufacturing process of wafer cleaning, due to the fact that van der waals force and electrostatic force can adsorb a large amount of particles, metal ions, organic matters and the like on the back of a wafer in various complex manufacturing processes, defects on the back of the wafer are caused, and the quality and the yield of the wafer are seriously affected.

However, in the prior art, the cleaning effect is not good when the BST (Backside surface treatment) technology is used to remove particles on the back surface of the wafer, and the particles still remain on the back surface, which affects the subsequent production and processing of the wafer and the yield of the wafer production.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a wafer cleaning device and wafer cleaning system can optimize the effect of getting rid of the particle at the wafer back to improve the yield of wafer production.

In order to solve the above technical problem, a wafer cleaning apparatus is provided, which includes a cleaning brush for cleaning impurities on a back surface of a wafer to be cleaned, and a sprayer capable of spraying a cleaning solution toward the wafer, wherein the cleaning solution has conductivity and is capable of releasing charges on the back surface of the wafer.

Optionally, the sprayer includes at least two nozzles, both of which are disposed toward the wafer, and at least one cleaning solution nozzle is included in the nozzles for spraying a cleaning solution having conductivity.

Optionally, the nozzles further include at least one deionized water nozzle for spraying deionized water, and all the nozzles are disposed toward the back surface of the wafer.

Optionally, the cleaning solution sprayed by the cleaning solution nozzle includes a carbonic acid solution.

Optionally, the system further comprises a control valve, which is arranged on the liquid path of the sprayer and used for controlling the on-off of the liquid path of the sprayer.

Optionally, the system further comprises a flow meter, wherein the flow meter is arranged on a liquid path of the sprayer and used for metering the spraying amount of the sprayer.

Optionally, the flow meter and the control valve are connected through a controller, and the controller controls the on-off of the control valve according to the measurement result of the flow meter.

In order to solve the above technical problem, a wafer cleaning system is further provided, which includes the wafer cleaning apparatus, and a cleaning liquid source, wherein the cleaning liquid source is used for providing a cleaning liquid to be sprayed, and the cleaning liquid source is communicated to the sprayer.

Optionally, the sprayer includes at least one cleaning solution nozzle for spraying cleaning solution, and the cleaning solution nozzle is communicated with the cleaning solution source.

Optionally, the sprayer includes at least one deionized water nozzle for spraying deionized water, and the sprayer further includes a deionized water source communicated with the deionized water nozzle for providing deionized water for spraying to the deionized water nozzle.

The utility model discloses a clean system of wafer cleaning device and wafer can spray the washing liquid that has electric conductivity towards the wafer back, releases the electric charge at the wafer back reduces because the electrostatic field that produces is in the existence of the electric charge at the wafer back, thereby reduces the wafer back is to the adsorption of particle, optimizes the effect of getting rid of the particle at the wafer back to improve the yield of wafer production.

Drawings

Fig. 1 is a schematic perspective view of a wafer cleaning apparatus according to an embodiment of the present invention.

Fig. 2 is a schematic side view of a wafer cleaning apparatus according to an embodiment of the present invention.

Fig. 3 is a schematic side view of a wafer cleaning apparatus according to an embodiment of the present invention.

Fig. 4 is a schematic diagram of the charge on the back side of the wafer according to an embodiment of the present invention.

Fig. 5 is a schematic diagram illustrating the discharge of the charge on the back side of the wafer according to an embodiment of the present invention.

Fig. 6 is a schematic diagram of the connection between the nozzle and the spraying pipeline according to an embodiment of the present invention.

Detailed Description

Research finds that the reason why the cleaning effect is not good when BST is used to remove the particles on the wafer back is that (1) when the brush brushes the wafer back, due to friction, charges are transferred between the wafer back and the brush, and the wafer back continuously accumulates electrostatic charges, which enhances the attraction of the wafer back to the particles, and here, please refer to fig. 4, which is a schematic diagram of the charges on the wafer back in an embodiment of the present invention; (2) the conductivity of the di water is low and the rinsing of the di water is not conducive to the discharge of static charges, making it difficult to release the attraction of particles to the backside of the wafer.

The wafer cleaning device and the wafer cleaning system according to the present invention will be described in detail with reference to the accompanying drawings and the detailed description.

Referring to fig. 1 and 2, fig. 1 is a schematic perspective view of a wafer cleaning apparatus according to an embodiment of the present invention; fig. 2 is a schematic side view of a wafer cleaning apparatus according to an embodiment of the present invention.

In this embodiment, a wafer cleaning apparatus is provided, which includes a cleaning brush 102 for cleaning impurities on the back surface of a wafer 100 to be cleaned, and a sprayer 101 capable of spraying a cleaning solution toward the wafer 100, the cleaning solution having conductivity capable of discharging charges on the back surface of the wafer 100.

In this embodiment, the wafer cleaning apparatus has a sprayer 101 capable of spraying a conductive cleaning solution toward the back surface of the wafer 100, so as to release the electric charge on the back surface of the wafer 100, and reduce the electrostatic field generated by the electric charge on the back surface of the wafer 100, so as to reduce the adsorption of particles on the back surface of the wafer 100, and reference is made to fig. 5, which is a schematic diagram of the present invention when the electric charge on the back surface of the wafer 100 is released.

In one embodiment, the cleaning brush 102 is disposed on the back side of the wafer 100 for cleaning the back side of the wafer 100. Reference is made here to fig. 1 and 2. In the embodiment shown in fig. 1 and 2, the cleaning brush 102 has two brush heads 1021 for contacting with the wafer 100, and in practice, the number of the brush heads 1021 may be set as required, for example, three or more. When a plurality of brush heads 1021 are provided, the brush heads 1021 of the cleaning brushes 102 are all disposed toward the wafer 100 and are uniformly disposed on the same plane. In one embodiment, the plane of the brush head 1021 of each cleaning brush 102 is parallel to the location where the wafer 100 is placed, such that the force of each brush head 1021 scrubbing the wafer 100 is uniform.

In one embodiment, the sprayer 101 includes at least two nozzles, each of which is disposed toward the wafer 100, and at least one cleaning solution nozzle 1012 for spraying a cleaning solution having conductivity. The conductive cleaning solution refers to a solution having freely movable ions, including positive ions, negative ions, and the like. The releasing of the charges on the back surface of the wafer 100 refers to the positive ions and the negative ions that can automatically move in the solution, and can neutralize the negative ions and the positive ions on the back surface of the wafer 100, thereby eliminating the charges on the back surface of the wafer 100 and releasing the attraction of the back surface of the wafer 100 to particles.

In the embodiment shown in fig. 1 to 3, all the nozzles are disposed toward the back surface of the wafer 100. This is because the brush head 1021 of the cleaning brush 102 is disposed toward the back side of the wafer 100, and the back side of the wafer 100 also accumulates a lot of charges due to the friction with the brush head 1021. The nozzle is arranged towards the back of the wafer 100, so that charges on the back of the wafer 100 can be rapidly removed, and the attraction of the back of the wafer 100 to particles is weakened.

As shown in fig. 2, the sprayer 101 includes one cleaning liquid nozzle 1012, and as shown in fig. 3, the sprayer 101 includes two cleaning liquid nozzles 1012. In practice, the number of the cleaning liquid nozzles 1012 may be set as desired. When a plurality of cleaning solution nozzles 1012 are provided, the cleaning solution nozzles 1012 are uniformly distributed on a first plane parallel to a placement position where the wafer 100 is placed, so as to uniformly spray the wafer 100. In fact, the specific position of the cleaning solution nozzle 1012 can be set as required.

The provision of the plurality of cleaning solution nozzles 1012 can increase the speed of releasing the back charges of the wafer 100, thereby improving the cleaning efficiency of the wafer 100.

In one embodiment, the nozzle further comprises at least one deionized water nozzle 1011 for spraying deionized water.

In fig. 2, the number of the deionized water nozzles 1011 is 1, and in fig. 3, the number of the deionized water nozzles 1011 is 2. In fact, the number of the deionized water nozzles 1011 may be set as desired. When a plurality of deionized water nozzles 1011 are provided, the plurality of deionized water nozzles 1011 are uniformly distributed on a second plane parallel to the placing position where the wafer 100 is placed, so as to uniformly spray the wafer 100. In a particular embodiment, the first plane coincides with the second plane.

In fact, the specific position of the deionized water nozzle 1011 may be set as desired.

In one embodiment, the cleaning solution sprayed by the cleaning solution nozzle 1012 includes a carbonic acid solution, which is generated by the reaction of water and carbon dioxide injected into the water. In practice, other weak acid solutions such as acetic acid, hydrofluoric acid, etc. may also be used. It should be noted that whatever weak acid solution is used, the wafer 100 after being sprayed needs to be cleaned, so as to prevent the cleaning solution on the wafer 100 from affecting the subsequent processing production of the wafer 100.

In one embodiment, as shown in fig. 6, the wafer cleaning apparatus further includes a control valve 601 disposed on the liquid path of the sprayer 101 for controlling the liquid path of the sprayer 101 to be opened or closed. In this embodiment, the control valve 601 is provided to a spray line 105 communicating with each nozzle, each nozzle communicating with a spray line 105, and the liquid to be sprayed is transported to the nozzle via the spray line 105. In this embodiment, the control valve 601 is disposed on the spraying liquid path, so that the spraying conditions of all the nozzles can be effectively controlled: when the control valve 601 is turned off, the spray nozzle stops spraying; when the control valve 601 is opened, the spray nozzle starts spraying.

In some embodiments, the control valve 601 may be partially opened, and the spray line 105 may be partially opened, so that a portion of the liquid may flow through the control valve 601 to the nozzle to be sprayed. In this case, the flow rate of the liquid discharged from the nozzle may be controlled by the control valve 601.

Please refer to fig. 6, which is a schematic diagram illustrating a connection between a nozzle and a spraying pipe 105 according to an embodiment of the present invention.

In this embodiment, the wafer cleaning apparatus further includes a flow meter 602 and a controller, wherein the flow meter 602 is disposed on a liquid path of the sprayer 101 and is used for measuring a spraying amount of the sprayer 101; the controller is connected with the flow meter 602 and the control valve 601, and controls the on-off of the control valve 601 according to the measurement result of the flow meter 602.

In this embodiment, the flow meter 602 is also provided to the shower line 105. In this embodiment, the flow meter 602 is disposed on the spraying pipe 105 to which each nozzle is connected, and the controller may acquire the liquid flow rate in the spraying pipe 105 to which each nozzle is connected, and control the control valve 601 according to the liquid flow rate to respectively regulate and control the spraying conditions of all the nozzles.

In this specific embodiment, because the control valve 601, the flow meter 602 and the controller are provided, and the control valve 601, the flow meter 602 and the controller form a closed loop, the controller can control the on-off condition of the control valve 601 according to the detection structure of the flow meter 602, so that the obtained control result is more accurate, and the spraying effect can be optimized.

In this embodiment, a wafer cleaning system is further provided, which includes the wafer cleaning apparatus as described above, and a cleaning liquid source 103, wherein the cleaning liquid source 103 is used for providing a cleaning liquid to be sprayed, and the cleaning liquid source 103 is connected to the sprayer 101.

In this embodiment, the wafer cleaning system includes a wafer cleaning apparatus having a sprayer 101 capable of spraying a conductive cleaning solution toward the back surface of the wafer 100, thereby releasing the charge on the back surface of the wafer 100, reducing an electrostatic field generated by the charge on the back surface of the wafer 100, and reducing the adsorption of particles on the back surface of the wafer 100.

In one embodiment, the sprayer 101 includes at least one cleaning solution nozzle 1012 for spraying a cleaning solution, and the cleaning solution nozzle 1012 is in communication with the cleaning solution source 103.

In one embodiment, the sprayer 101 includes at least one deionized water nozzle 1011 for spraying deionized water, and the sprayer 101 further includes a deionized water source 104 in communication with the deionized water nozzle 1011 for providing deionized water for spraying to the deionized water nozzle 1011.

In one embodiment, all of the nozzles are disposed toward the back side of the wafer 100. This is because the brush head 1021 of the cleaning brush 102 is disposed toward the back side of the wafer 100, and the back side of the wafer 100 also accumulates a lot of charges due to the friction with the brush head 1021. The nozzle is arranged towards the back of the wafer 100, so that charges on the back of the wafer 100 can be rapidly removed, and the attraction of the back of the wafer 100 to particles is weakened.

As shown in fig. 2, the sprayer 101 includes one cleaning liquid nozzle 1012, and as shown in fig. 3, the sprayer 101 includes two cleaning liquid nozzles 1012. In practice, the number of the cleaning liquid nozzles 1012 may be set as desired. When a plurality of cleaning solution nozzles 1012 are provided, the cleaning solution nozzles 1012 are uniformly distributed on a first plane parallel to a placement position where the wafer 100 is placed, so as to uniformly spray the wafer 100. In fact, the specific position of the cleaning solution nozzle 1012 can be set as required.

The provision of the plurality of cleaning solution nozzles 1012 can increase the speed of releasing the back charges of the wafer 100, thereby improving the cleaning efficiency of the wafer 100.

The deionized water nozzle 1011 is arranged to spray deionized water, so that cleaning liquid stained on the back surface of the wafer 100 can be cleaned, the cleaning liquid on the back surface of the wafer 100 can be flushed away while charges on the back surface of the wafer 100 are removed, and the cleaning liquid is prevented from interfering with subsequent processing production of the wafer 100.

In fig. 2, the number of the deionized water nozzles 1011 is 1, and in fig. 3, the number of the deionized water nozzles 1011 is 2. In fact, the number of the deionized water nozzles 1011 may be set as desired. When a plurality of deionized water nozzles 1011 are provided, the plurality of deionized water nozzles 1011 are uniformly distributed on a second plane parallel to the placing position where the wafer 100 is placed, so as to uniformly spray the wafer 100. In a particular embodiment, the first plane coincides with the second plane.

In fact, the specific position of the deionized water nozzle 1011 may be set as desired.

In one embodiment, the cleaning solution source 103 comprises a carbon acid source, and in fact, the cleaning solution source 103 may be other weak acid sources, such as an acetic acid source, a hydrofluoric acid source, etc., where a weak acid is used because a strong acid may have a corrosive effect on the backside of the wafer 100.

In this embodiment, there is also provided a wafer cleaning method, comprising the steps of: a conductive cleaning solution is sprayed to the back surface of the wafer 100 to be cleaned.

In this embodiment, the wafer cleaning method sprays the conductive cleaning solution toward the back surface of the wafer 100, so as to release the charges on the back surface of the wafer 100, reduce the electrostatic field generated by the charges on the back surface of the wafer 100, and reduce the adsorption of particles on the back surface of the wafer 100.

In one embodiment, a conductive cleaning solution is sprayed onto the back surface of the wafer 100 to be cleaned, and the cleaning solution includes a carbonic acid solution.

In fact, in other embodiments, other weak acid solutions, such as acetic acid, hydrofluoric acid, etc., may be used as the cleaning solution. It should be noted that whatever weak acid solution is used, the wafer 100 after being sprayed needs to be cleaned, so as to prevent the cleaning solution on the wafer 100 from affecting the subsequent processing production of the wafer 100.

In one embodiment, the method further comprises the following steps: and acquiring the sprayed spraying amount of the cleaning liquid, and adjusting the subsequent spraying amount according to the sprayed spraying amount. In this embodiment, this may be accomplished by adding a control valve 601 and flow meter 602 to the cleaning solution spray line 105. Specifically, a control valve 601 and a flow meter 602 are added to the cleaning liquid spraying pipeline 105, the control valve 601 and the flow meter 602 are connected to a controller, and the controller controls the on-off state of the control valve 601 according to the detection result of the flow meter 602, so as to control the spraying amount of the cleaning liquid.

In this specific embodiment, because the control valve 601, the flow meter 602 and the controller are provided, and the control valve 601, the flow meter 602 and the controller form a closed loop, the controller can control the on-off condition of the control valve 601 according to the detection structure of the flow meter 602, so that the obtained control result is more accurate, and the spraying effect can be optimized.

In one embodiment, the method further comprises the following steps: before spraying conductive cleaning liquid on the back surface of a wafer 100 to be cleaned, brushing the back surface of the wafer 100 by using a cleaning brush 102, and flushing the back surface of the wafer 100 by using deionized water; after spraying conductive cleaning solution on the back surface of the wafer 100 to be cleaned, spraying deionized water on the back surface of the wafer 100. This is because the wafer 100 sprayed with the cleaning solution needs to be cleaned with deionized water, so as to prevent the cleaning solution on the wafer 100 from affecting subsequent processing of the wafer 100.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims (10)

1. A wafer cleaning device comprises a cleaning brush used for cleaning impurities on the back of a wafer to be cleaned, and is characterized by further comprising a sprayer which can spray cleaning liquid towards the wafer, wherein the cleaning liquid is conductive and can release charges on the back of the wafer.

2. The wafer cleaning apparatus as claimed in claim 1, wherein the sprayer includes at least two nozzles each disposed toward the wafer, and at least one of the nozzles includes a cleaning solution nozzle for spraying a cleaning solution having conductivity.

3. The wafer cleaning apparatus as claimed in claim 2, wherein the nozzles further comprise at least one deionized water nozzle for spraying deionized water, and all of the nozzles are disposed toward the back surface of the wafer.

4. The wafer cleaning apparatus as claimed in claim 2, wherein the cleaning solution sprayed by the cleaning solution nozzle comprises a carbonic acid solution.

5. The wafer cleaning device as claimed in claim 1, further comprising a control valve disposed on a liquid path of the sprayer for controlling the liquid path of the sprayer to be turned on or off.

6. The wafer cleaning device as claimed in claim 5, further comprising a flow meter disposed on a liquid path of the sprayer for metering a spraying amount of the sprayer.

7. The wafer cleaning device as claimed in claim 6, further comprising a controller, wherein the controller is connected to the flow meter and the control valve, and controls the on/off of the control valve according to the measurement result of the flow meter.

8. A wafer cleaning system comprising the wafer cleaning apparatus as claimed in any one of claims 1 to 7, and a cleaning liquid source for providing a cleaning liquid to be sprayed, the cleaning liquid source being connected to the sprayer.

9. The wafer cleaning system of claim 8, wherein the sprayer includes at least one cleaning fluid nozzle for spraying a cleaning fluid, and the cleaning fluid nozzle is in communication with the cleaning fluid source.

10. The wafer cleaning system of claim 8, wherein the sprayer includes at least one deionized water nozzle for spraying deionized water, the sprayer further including a deionized water source in communication with the deionized water nozzle for providing deionized water for spraying to the deionized water nozzle.

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