Substrate cleaning device

Abstract

The purpose of the present disclosure is to provide a substrate cleaning device capable of removing a substance to be removed that is adhered to a cleaning surface of a substrate while suppressing the use amount of the cleaning liquid. A mist ejection unit (21) ejects a relay mist gas (MG1) including cleaning liquid mist (MT) along the mist ejection direction (F21). An air knife (23) blows air gas (AG1) to the relay mist gas (MG1) along the air gas blowing direction (FG1) during the period in which the operation of conveying a substrate (1) by the conveyance means is performed, to join the air gas (AG1) to the relay mist gas (MG1), and thereby a cleaning mist gas (MG2) is obtained. A first air gas blowing process is thus conducted. The cleaning mist gas (MG2), which is supplied by the first air gas blowing process, is directly blown onto the surface of the substrate (1) to be conveyed.

Description

Substrate Cleaning Equipment

[0001] The present disclosure relates to a substrate cleaning device that cleans a substrate, for example, a substrate cleaning device that cleans a substrate used in a plating processing device that forms a metal film in the manufacture of electronic components, etc.

[0002] Conventional cleaning devices for cleaning substrates and the like used in plating processing devices that form metal films in the manufacture of electronic components and the like include, for example, the sealed cleaning device disclosed in Patent Document 1, the substrate liquid processing device disclosed in Patent Document 2, the substrate cleaning device disclosed in Patent Document 3, the cleaning device disclosed in Patent Document 4, and the cleaning device disclosed in Patent Document 5.

[0003] The cleaning devices disclosed in Patent Documents 1 to 3 basically spray a cleaning liquid directly onto the object to clean it. The cleaning device disclosed in Patent Document 4 performs cleaning in a mist atmosphere. The cleaning device disclosed in Patent Document 5 performs cleaning by spraying a cleaning liquid directly onto the object placed in a mist atmosphere.

[0004] Japanese Patent Application Laid-Open No. 11-76962 International Publication No. 2018 / 501665 Japanese Patent Application Laid-Open No. 2009-136742 Japanese Patent Application Laid-Open No. 2020-18993 Japanese Patent Application Laid-Open No. 2007-33730

[0005] The conventional cleaning devices disclosed in Patent Documents 1 to 5 basically spray cleaning liquid, including a mist, directly onto the object to be cleaned, which has the problem of using a large amount of cleaning liquid.

[0006] An object of the present disclosure is to provide a substrate cleaning device that can solve the above-mentioned problems and reduce the amount of cleaning liquid used.

[0007] The substrate cleaning device according to the present disclosure includes a conveying means for performing a conveying operation of conveying a substrate along a conveying direction, and a mist gas supply mechanism for supplying a cleaning mist gas containing a cleaning liquid mist obtained by misting a cleaning liquid to clean a cleaning surface of the substrate, the mist gas supply mechanism including a mist ejection unit for ejecting a relay mist gas containing the cleaning liquid mist along a mist ejection direction, and a first air gas spraying unit for spraying a first air gas spraying direction to the relay mist gas during a period in which the conveying operation is performed by the conveying means. and a first air gas spraying section that performs a first air gas spraying process to spray an air gas of the first type onto the cleaning surface of the substrate and merge the first air gas into the relay mist gas to obtain the cleaning mist gas, wherein the cleaning mist gas is supplied to the cleaning surface of the substrate by the first air gas spraying process, the flow rate of the relay mist gas is set to an initial mist flow rate, the flow rate of the first air gas is set to a first air gas flow rate, and the first air gas flow rate is set to be faster than the initial mist flow rate.

[0008] The mist gas supply mechanism in the substrate cleaning device of the present disclosure is configured to include the above-mentioned mist ejection section and first air gas spraying section, and the first air gas flow velocity is set to be faster than the initial mist flow velocity.

[0009] Therefore, the cleaning mist gas obtained by the joining of the relay mist gas and the first air gas is influenced by the first air gas, the supply direction of the cleaning mist gas is the same as the spray direction of the first air gas, and the final mist gas flow velocity, which is the flow velocity of the cleaning mist gas, is approximately the same as the flow velocity of the first air gas.

[0010] Therefore, by setting the first air gas flow rate to the flow rate required for cleaning the cleaning surface of the substrate, the amount of cleaning liquid mist contained in the cleaning mist gas can be kept to a necessary minimum, and the cleaning liquid mist can be efficiently supplied to the cleaning surface of the substrate.

[0011] As a result, the substrate cleaning device of the present disclosure can reduce the amount of cleaning liquid used and remove the materials adhering to the cleaning surface of the substrate.

[0012] The objects, features, aspects, and advantages of the present disclosure will become more apparent from the following detailed description and the accompanying drawings.

[0013] FIG. 1 is an explanatory diagram schematically showing the overall configuration of a substrate cleaning apparatus according to a first embodiment. FIG. 1 is an explanatory diagram schematically showing the configuration of the mist gas supply mechanism shown in FIG. 1. FIG. 1 is an explanatory diagram schematically showing an air knife and its periphery in the liquid drainer mechanism shown in FIG. 1. FIG. 1 is an explanatory diagram schematically showing the adjustment function of the air knife in the mist gas supply mechanism. FIG. 1 is an explanatory diagram schematically showing the adjustment function of the mist jetting section in the mist gas supply mechanism. FIG. 5 is a block diagram showing a configuration for realizing the adjustment functions of the mist jetting section and air knife shown in FIGS. 4 and 5. FIG. 16 is an explanatory diagram showing the mist diffusion prevention plate and its periphery shown in FIG. 1. FIG. 17 is an explanatory diagram showing the planar configuration of the mist diffusion prevention plate. FIG. 18 is an explanatory diagram showing the configuration of a comparative substrate cleaning apparatus. FIG. 19 is an explanatory diagram schematically showing the overall configuration of a substrate cleaning apparatus according to a second embodiment. FIG. 19 is an explanatory diagram schematically showing the configuration of the mist gas supply mechanism shown in FIG. 10. FIG. 19 is an explanatory diagram showing the structure of the adsorption mechanism shown in FIGS. 10 and 11.

[0014] <Introduction> The substrate cleaning device disclosed herein is a device for cleaning substrates, for example, a device for cleaning substrates used in a plating processing device that forms a metal coating in the manufacture of electronic components, etc. A more specific example is a substrate cleaning device that cleans plating solution adhering to a substrate to be treated, such as a metal substrate or a printed circuit board, after plating in a plating process. For example, on a substrate 1 after plating, there are plated areas and areas that are not plated and where plating solution remains, and the plating solution remaining in each of the former and latter areas is a cleaning target that must be removed.

[0015] 1 is an explanatory diagram that schematically shows the overall configuration of a substrate cleaning device 51 according to embodiment 1. An XYZ Cartesian coordinate system is depicted in the drawing.

[0016] As shown in the figure, a substrate 1 is placed on a conveyor table 2, and a material to be removed 3, such as a plating solution, is attached to the surface of the substrate 1. This material to be removed 3 is the object to be cleaned by the substrate cleaning device 51. In the first embodiment, the surface of the substrate 1 is the cleaning surface, and the material to be removed 3 is assumed to be the plating solution adhering to the surface of the substrate 1.

[0017] The substrate cleaning device 51 includes a conveying means, an ultrasonic atomizer 11, a mist supply pipe 12, a mist gas supply mechanism 20, and a liquid draining mechanism 30 as main components.

[0018] The transport means includes the above-described transport table 2 and a transport device such as a conveyor (not shown). The transport means performs a transport operation of transporting the substrate 1 along the table transport direction T2 (+X direction) by moving the transport table 2 along the table transport direction T2 using the transport device.

[0019] The ultrasonic atomizer 11 contains a cleaning liquid (not shown) and generates a cleaning liquid mist MT having a droplet size of 15 μm or less by applying ultrasonic vibrations to the cleaning liquid. The cleaning liquid mist MT generated by the ultrasonic atomizer 11 is supplied to the mist jetting portion 21 of the mist gas supply mechanism 20 via the mist supply pipe 12 by a carrier gas (not shown). In the first embodiment, pure water is used as the cleaning liquid.

[0020] Other than the ultrasonic wave propagation method that applies ultrasonic vibrations to the cleaning liquid, other techniques for generating the cleaning liquid mist MT include pressure, rotation, steam, piezoelectric, thermal, electrostatic, etc. However, when generating a cleaning liquid mist MT with a relatively small (droplet) particle size of 15 μm or less, it is desirable to adopt the ultrasonic vibration propagation method.

[0021] The mist gas supply mechanism 20 supplies cleaning mist gas MG2 containing cleaning liquid mist MT, which is a mist of cleaning liquid, toward the surface of the substrate 1 in order to clean the object to be removed 3 attached to the surface, which is the cleaning surface of the substrate 1.

[0022] The mist gas supply mechanism 20 includes, as its main components, a mist jetting section 21 and an air knife 23 which is a first air gas blowing section.

[0023] The mist ejection part 21 ejects relay mist gas MG1 containing cleaning liquid mist MT along a mist ejection direction F21. At this time, the relay mist gas MG1 is supplied to the outlet of the air gas AG1 of the air knife 23 or the vicinity of the outlet. Here, the flow velocity of the relay mist gas MG1 is defined as mist gas flow velocity V21. This mist gas flow velocity V21 is the initial mist flow velocity.

[0024] The mist ejection section 21 is realized by transporting the cleaning liquid mist MT using a carrier gas (not shown) for ejection having a directionality along the mist gas ejection direction F21. In this case, a mixture of the cleaning liquid mist MT and the carrier gas becomes the relay mist gas MG1.

[0025] The particle size of the cleaning liquid mist MT generated by applying ultrasonic vibrations in the ultrasonic atomizer 11 is 15 μm or less, which is smaller than the particle size of a typical spray mist, and the falling speed of the cleaning liquid mist MT is slow, so it is possible to handle the cleaning liquid mist MT as relay mist gas MG1 by carrying it on a gas flow having a directional mist gas ejection direction F21.

[0026] The air knife 23, which is the first air gas spraying unit, sprays air gas AG1 along the air gas spraying direction FG1 toward the relay mist gas MG1 during the period when the transport means is performing the transport operation, and performs a first air gas spraying process to obtain a cleaning mist gas MG2 by merging the air gas AG1 with the relay mist gas MG1. The air gas AG1 becomes the first air gas, and atmospheric air, nitrogen, or the like is used as the air gas AG1.

[0027] Here, if the flow velocity of the air gas AG1, which is the first air gas, is defined as an air gas flow velocity VG1 (first air gas flow velocity), the air gas flow velocity VG1 is set to be faster than the mist gas flow velocity V21. Specifically, the velocity ratio {VG1:V21} between the air gas flow velocity VG1 and the mist gas flow velocity V21 is set to, for example, {10:1}.

[0028] In this way, since the air gas flow velocity VG1 is set to be faster than the mist gas flow velocity V21, when the relay mist gas MG1 merges with the air gas AG1, it is caught up in the flow of the air gas AG1 and is therefore greatly affected by the air gas AG1.

[0029] Here, the flow velocity of the cleaning mist gas MG2 is referred to as the mist gas flow velocity V23, and the supply direction of the cleaning mist gas MG2 is referred to as the mist gas supply direction F23. As described above, the cleaning mist gas MG2 is significantly affected by the air gas AG1, so the mist gas supply direction F23 is the same as the air gas spray direction FG1, and the mist gas flow velocity V23 is approximately the same as the air gas flow velocity VG1. This is because the mist gas flow velocity V21 of the relay mist gas MG1 is slower than the air gas flow velocity VG1 of the air gas AG1, resulting in the Coanda effect.

[0030] In this way, with regard to the cleaning mist gas MG2 obtained by the confluence of the relay mist gas MG1 and the air gas AG1, the mist gas supply direction F23 is the same direction as the air gas spraying direction FG1, and the mist gas flow velocity V23 is approximately the same as the air gas flow velocity VG1.

[0031] The cleaning mist gas MG2 obtained by merging the relay mist gas MG1 with the air gas AG1 passes below the mist diffusion prevention plate 4, which will be described in detail later, and is supplied toward the transport path of the transport table 2, which is transported along the table transport direction T2.

[0032] Therefore, the cleaning mist gas MG2 supplied by the first air gas spraying process is directly sprayed onto the surface of the substrate 1 while the transporting means is performing the transporting operation.

[0033] At this time, the mist gas flow velocity V23 of the cleaning mist gas MG2 is approximately the same as the air gas flow velocity VG1 of the air gas AG1, and therefore the mist gas is sprayed at a relatively high mist gas flow velocity V23 directly onto the objects 3 to be removed adhering to the surface of the substrate 1. Therefore, the cleaning mist gas MG2 having the mist gas flow velocity V23 can sweep away the objects 3 to be removed, such as the plating solution.

[0034] As a result, by spraying cleaning mist gas MG2 containing cleaning liquid mist MT onto the surface of the substrate 1, the object to be removed 3 attached to the surface of the substrate 1 is removed or decomposed, and the object to be removed 3 to be cleaned is cleaned.

[0035] The liquid draining mechanism 30 includes, as a main component, an air knife 31. The air knife 31, which is the second air gas blowing unit, is disposed downstream of the air knife 23, which is the first air gas blowing unit, in the table conveying direction T2.

[0036] The air gas AG2 blown out by the air knife 31, which is the second air gas blowing section, along the air gas blowing direction FG2 passes below the mist diffusion prevention plate 4 and is supplied toward the transport path of the transport table 2, which is transported along the table transport direction T2, during the period when the above-mentioned transport operation is being performed by the above-mentioned transport means.

[0037] Therefore, the air knife 31, which is the second air gas spraying section, performs a second air gas spraying process in which the second air gas, air gas AG2, is directly sprayed onto the remaining material on the surface of the substrate 1 during the period in which the above-mentioned conveying operation is being performed by the above-mentioned conveying means.

[0038] The air gas blowing direction FG1 of the air gas AG1 (mist gas supply direction F23) and the air gas blowing direction FG2 of the air gas AG2 each have a directional component in the opposite transport direction (-X direction) that is opposite to the table transport direction T2.

[0039] The second air gas blowing process using the air knife 31 can remove any residue remaining on the surface of the substrate 1. The residue may be a part of the object 3 to be removed, cleaning liquid, or the like.

[0040] In Figure 1, the table transport direction T2 of the substrate 1 is the horizontal direction (X direction), but the table transport direction T2 may be a direction that is inclined with respect to the X direction, or the table transport direction T2 may be the vertical direction (Z direction).

[0041] In addition, in FIG. 1, the surface to be cleaned of the substrate 1 is the front surface (upper surface) of the substrate 1, but the back surface (lower surface) of the substrate 1 may also be the surface to be cleaned.

[0042] 2 is an explanatory diagram schematically illustrating the configuration of the mist gas supply mechanism 20. As shown in the figure, the distance along the mist gas ejection direction F21 from when the relay mist gas MG1 joins the air gas AG1 is the output port distance D13. The output port distance D13 is the distance from the ejection port (tip portion) of the mist ejection unit 21 to the area surrounding the outlet (tip portion) of the air knife 23. This output port distance D13 is set so that the relay mist gas MG1 and the air gas AG1 join together to accurately produce the cleaning mist gas MG2 having a mist gas supply direction F23 that matches the air gas spraying direction FG1.

[0043] In addition, the gap G23, which is the distance along the vertical direction (Z direction) from the surface 1s that will be the cleaning surface of the substrate 1 to the outlet of the air knife 23, is set to a length that will increase the removal effect of the object 3 to be removed.

[0044] The gas flow supply angle A23, which is the angle of the mist gas supply direction F23 with respect to the table conveying direction T2 (+X direction), is set in the range of 0 to 90 degrees (greater than 0 degrees and less than 90 degrees: 0 (degrees) < A23 < 90 (degrees)). This gas flow supply angle A23 becomes the first air gas spraying angle.

[0045] It is not desirable to set the gas flow supply angle A23, which is the first air gas spraying angle, outside the range of 0 to 90 degrees, because when the material 3 to be removed is pushed away and removed, the material 3 may flow over the surface of the substrate 1 that is to be cleaned, thereby contaminating the surface of the substrate 1.

[0046] When the air gas AG1 is blown out from the air knife 23, the gas supply pressure to the air knife 23 is set to a pressure that will give a desired air gas flow velocity VG1.

[0047] It is desirable that the transport speed of the substrate 1 along the table transport direction T2 by the transport means be appropriately set within a range that reduces the amount of cleaning liquid mist MT contained in the cleaning mist gas MG2 used while maintaining a moderate cleaning effect on the object to be removed 3.

[0048] 3 is an explanatory diagram schematically showing the air knife 31 and its periphery. The air gas flow velocity VG2 (second air gas flow velocity) of the air gas AG2 (second air gas) blown out from the air knife 31, which is the second air gas blowing section, is set so that the effect of removing residual material on the surface of the substrate 1 maintains a desired removal level and the degree of dryness of the surface of the substrate 1 is equal to or lower than a predetermined dryness level.

[0049] The higher the air gas flow velocity VG2, which is the second air gas flow velocity, the greater the effect of removing residual material, and the lower the air gas flow velocity VG2, the lower the degree of dryness on the surface of the substrate 1. If the substrate 1 is made of a material that is easily oxidized, the residual material on the surface of the substrate 1 may oxidize and contaminate the substrate 1 if the degree of dryness on the surface of the substrate 1 increases. The air gas flow velocity VG2 can be adjusted by the gas supply pressure to the air knife 31.

[0050] Furthermore, a gap G31 along the vertical direction (Z direction) from the surface to be cleaned of the substrate 1 to the air outlet of the air knife 31 is set to a distance that is effective in removing residual material and that does not move the substrate 1 placed on the conveying table 2. If the gap G31 is short, the wind force of the air gas AG2 will increase, and there is a possibility that the substrate 1 will move from the conveying table 2.

[0051] The gas flow supply angle A31, which is the angle of the air gas blowing direction FG2 with respect to the table conveying direction T2 (X direction), is set in the range of 0 to 90 degrees (greater than 0 degrees and less than 90 degrees: 0 (degrees) < A31 < 90 (degrees)). This gas flow supply angle A23 becomes the second air gas blowing angle.

[0052] It is not desirable to set the gas flow supply angle A31, which is the second air gas spraying angle, outside the range of 0 to 90 degrees, because when the residual matter is swept away and removed, the residual matter may flow over the surface of the substrate 1 that is to be cleaned, thereby contaminating the surface of the substrate 1.

[0053] Fig. 4 is an explanatory diagram showing the adjustment function of the air knife 23. Fig. 5 is an explanatory diagram showing the adjustment function of the mist ejection part 21. Fig. 6 is a block diagram showing the configuration for realizing the adjustment functions of the mist ejection part 21 and the air knife 23.

[0054] As shown in FIG. 6, the air knife 23 is connected to an air knife rotating mechanism 23R and an air knife moving mechanism 23M.

[0055] The air knife moving mechanism 23M is a mechanism that moves the air knife 23 along the movement direction T23X or the movement direction T23Z. Therefore, the substrate cleaning device 51 having the air knife moving mechanism 23M has a first spraying unit moving function that moves the air knife 23, which is the first air gas spraying unit, along the movement direction T23X or the movement direction T23Z. The movement direction T23X is parallel to the X direction, and the movement direction T23Z is parallel to the Z direction.

[0056] The air knife rotation mechanism 23R is a mechanism that rotates the air knife 23 in a rotation direction R23, with a predetermined location of the air knife 23 in the XZ plane as the rotation axis. Therefore, the substrate cleaning device 51 having the air knife rotation mechanism 23R has a first spray angle adjustment function that adjusts the gas flow supply angle A23, which is the first air gas spray angle, by rotating the air knife 23 in the rotation direction R23.

[0057] Air knife moving mechanism 23M may have any configuration and may be realized using existing technology as long as it can move air knife 23 without changing gas flow supply angle A23. Air knife rotating mechanism 23R may have any configuration and may be realized using existing technology as long as it can rotate air knife 23 along rotation direction R23.

[0058] As shown in FIG. 6, the mist jetting part 21 is connected to a mist jetting part rotating mechanism 21R and a mist jetting part moving mechanism 21M.

[0059] The mist jetting unit moving mechanism 21M is a mechanism that moves the mist jetting unit 21 along the movement direction T21X or the movement direction T21Z. Therefore, the substrate cleaning device 51 having the mist jetting unit moving mechanism 21M has a jetting unit moving function that moves the mist jetting unit 21 along the movement direction T21X or the movement direction T23Z. The movement direction T21X is parallel to the X direction, and the movement direction T21Z is parallel to the Z direction.

[0060] The mist jetting unit rotation mechanism 21R rotates the mist jetting unit 21 in a rotation direction R21, using a predetermined location of the mist jetting unit 21 in the XZ plane as the rotation axis. Therefore, the substrate cleaning device 51 having the mist jetting unit rotation mechanism 21R has a jetting angle adjustment function that adjusts the mist supply angle A21, which is the mist jetting angle with respect to the table conveying direction T2, by rotating the mist jetting unit 21 in the rotation direction R21. The mist supply angle A21 is set in the range of 0 to 90 degrees (greater than 0 degrees and less than 90 degrees: 0 (degrees) < A21 < 90 (degrees)).

[0061] The mist-jet-portion-moving mechanism 21M can have any configuration and can be realized using existing technology as long as it can move the mist-jet portion 21 without changing the mist supply angle A21. The mist-jet-portion-rotating mechanism 21R can have any configuration and can be realized using existing technology as long as it can rotate the air knife 23 along the rotation direction R21.

[0062] (Mist diffusion prevention plate 4) The substrate cleaning apparatus 51 of the first embodiment has a mist diffusion prevention plate 4. The mist diffusion prevention plate 4 is disposed between the mist gas supply mechanism 20 and the substrate 1, and has a flat plate shape. The plate shape is shaped along the XY plane.

[0063] Fig. 7 is an explanatory diagram showing the mist diffusion prevention plate 4 and its periphery, and Fig. 8 is an explanatory diagram showing the planar configuration of the mist diffusion prevention plate 4. An XYZ Cartesian coordinate system is depicted in each of Figs. 7 and 8.

[0064] The mist diffusion prevention plate 4 is positioned so as to provide a diffusion suppression space S1 having a predetermined gap G4 without interfering with the supply of the cleaning mist gas MG2 to the surface 1s, which is the cleaning surface of the substrate 1. The gap G4 is the distance along the Z direction between the back surface 4r of the mist diffusion prevention plate 4 and the surface 1s of the substrate 1, and the diffusion suppression space S1 is a space having the gap G4 formed between the surface 1s of the substrate 1 and the back surface 4r of the mist diffusion prevention plate 4.

[0065] As shown in FIG. 8, the plane shape of the mist diffusion prevention plate 4 is set to be sufficiently wide, so that most of the space above the surface 1s of the base material 1 can be used as the diffusion suppression space S1.

[0066] By setting the predetermined gap G4 sufficiently short to narrow the diffusion suppression space S1, the diffusion of the cleaning liquid mist MT contained in the cleaning mist gas MG2 can be suppressed. It is desirable to set the gap G4 (μm) within a range that satisfies {15 μm<G4≦50 mm}.

[0067] That is, in the substrate cleaning apparatus 51 of the first embodiment, the cleaning liquid mist MT is assumed to have a particle size (of droplets) of 15 μm or less, and the gap G4 is set to a length exceeding the particle size of the cleaning liquid mist MT.

[0068] 9 is an explanatory diagram showing the configuration of a comparative substrate cleaning apparatus 51X, which is the substrate cleaning apparatus 51 of the first embodiment without the mist diffusion prevention plate 4. An XYZ Cartesian coordinate system is shown in the figure. FIG. 9 shows a state in which a material to be removed 3 is attached to a part of the surface of a substrate 1.

[0069] As shown in the figure, when the cleaning mist gas MG2 is supplied to the surface 1s of the substrate 1, the cleaning liquid mist MT contained in the cleaning mist gas MG2 is lightweight, so a portion of the cleaning liquid mist MT diffuses above the substrate 1. The comparative substrate cleaning apparatus 51X does not have a mist diffusion prevention plate 4, and therefore cannot suppress the diffusion phenomenon of the cleaning liquid mist MT.

[0070] Therefore, since the cleaning mist gas MG2 becomes a drier gas as the cleaning liquid mist MT diffuses, the dry cleaning mist gas MG2 is sprayed onto the surface 1 s of the substrate 1, which makes it easier to dry the surface 1 s of the substrate 1. If the surface 1 s of the substrate 1 in a dried state is oxidized, the surface 1 s of the substrate 1 will become dirty.

[0071] On the other hand, in the substrate cleaning apparatus 51 of the first embodiment, the space above the surface 1 s of the substrate 1 is narrowed to the diffusion suppression space S1 by the presence of the mist diffusion prevention plate 4, so that the diffusion of the cleaning liquid mist MT contained in the cleaning mist gas MG2 can be effectively suppressed. Therefore, the substrate cleaning apparatus 51 of the first embodiment can prevent the surface 1 s from drying out, thereby avoiding the phenomenon of the surface 1 s being oxidized and contaminated.

[0072] (Effect) The mist gas supply mechanism 20 in the substrate cleaning device 51 according to the first embodiment of the present disclosure is configured to include a mist ejection section 21 and an air knife 23, and the first air gas flow velocity, VG1, is set to be faster than the mist gas flow velocity V21 of the relay mist gas MG1.

[0073] Therefore, the cleaning mist gas MG2 obtained by merging the relay mist gas MG1 with the air gas AG1 is influenced by the air gas AG1, so that the mist gas supply direction F23 of the cleaning mist gas MG2 becomes the same direction as the air gas spraying direction FG1, and the mist gas flow velocity V23 becomes approximately the same as the air gas flow velocity VG1.

[0074] Therefore, by setting the air gas flow velocity VG1 to the flow velocity required for cleaning the surface 1s, which is the cleaning surface of the substrate 1, the amount of cleaning liquid mist MT contained in the cleaning mist gas MG2 can be kept to the minimum necessary, and the cleaning liquid mist MT can be efficiently supplied to the surface of the substrate 1.

[0075] As a result, the substrate cleaning apparatus 51 of the first embodiment can remove the objects 3 adhering to the surface of the substrate 1 while reducing the amount of cleaning liquid used.

[0076] The substrate cleaning device 51 of embodiment 1 supplies cleaning mist gas MG2 onto the transport path of the transport table 2 and directly sprays the cleaning mist gas MG2 containing cleaning liquid mist MT onto the surface of the substrate 1, thereby accurately removing the object to be removed 3 attached to the surface of the substrate 1.

[0077] Below, an example of the cleaning effect of the substrate cleaning device 51 of the first embodiment will be shown, in which the object 3 to be removed is a nickel plating solution and the cleaning liquid is pure water.

[0078] The substrate 1 was a Hull Cell copper substrate with a planar size of 100 mm × 100 mm and a thickness of 0.3 mm. 2 mL of nickel plating solution was dropped onto the surface to be cleaned, and the dropped plating solution was spread to remove unnecessary plating solution. In this way, a nickel plating solution weighing 0.6 to 0.7 g and having a thickness of approximately 0.5 mm was adhered to the surface of the substrate 1 as the object to be removed 3.

[0079] During the period in which the conveying operation is performed in which the conveying table 2 is conveyed by the conveying means along the table conveying direction T2 at a substrate conveying speed of 200 mm / min for the substrate 1 having the material to be removed 3 adhering to its surface as described above, cleaning mist gas MG2 is sprayed from the mist gas supply mechanism 20 onto the surface of the substrate 1, and the remaining material on the surface of the substrate 1 is removed with the air knife 31.

[0080] As a result, the analysis result obtained by ICP-MS (Inductively Coupled Plasma Mass Spectrometry) showed that the substrate cleaning apparatus 51 of embodiment 1 reduced the amount of attached nickel plating solution, which is the object to be removed 3, to 22 μg.

[0081] In this way, the substrate cleaning apparatus 51 of the first embodiment can accurately remove the objects 3 adhering to the surface of the substrate 1 .

[0082] It should be noted that, even if the cleaning mist gas MG2 is not directly sprayed onto the surface of the substrate 1, if an atmosphere of the cleaning mist gas MG2 can be formed on the surface of the conveying table 2, the objects 3 to be removed adhering to the surface of the substrate 1 can be removed. For example, an environment in which the cleaning mist gas MG2 is indirectly supplied can be considered, such as a conveying path for the conveying table 2 being provided on the downwind side of the cleaning mist gas MG2, and the surface of the substrate 1 passing through an atmosphere of the cleaning mist gas MG2.

[0083] However, to enhance the cleaning effect of removing the object 3, an environment in which the cleaning mist gas MG2 is directly sprayed onto the surface of the substrate 1 is more preferable than an environment in which the cleaning mist gas MG2 is indirectly supplied.

[0084] The substrate cleaning device 51 of embodiment 1 can accurately remove any residue remaining on the surface 1 s of the substrate 1 by directly blowing the second air gas, air gas AG2, from the air knife 31, which is the second air gas spraying section, onto the surface 1 s, which is the cleaning surface of the substrate 1.

[0085] The substrate cleaning apparatus 51 of the first embodiment is provided with the ultrasonic atomizer 11, and thus can supply the cleaning liquid mist MT having a relatively small particle size, for example, 15 μm or less, to the mist spraying part 21 via the mist supply pipe 12.

[0086] As a result, the cleaning liquid mist MT contained in the cleaning mist gas MG2 supplied from the substrate cleaning device 51 of embodiment 1 can penetrate even the finest parts on the surface of the substrate 1, and by reducing the amount of cleaning liquid contained in one droplet of the cleaning liquid mist MT, the amount of cleaning liquid used can be reduced to the minimum necessary.

[0087] With regard to the air knife 23 in the substrate cleaning device 51 of embodiment 1, the air gas spraying direction FG1 (mist gas supply direction F23) has a directional component in the transport opposing direction that is opposite to the table transport direction T2, and the gas flow supply angle A23, which is the first air gas spraying angle, is set in the range of 0 to 90 degrees (0 (degrees) < A23 < 90 (degrees)).

[0088] Therefore, the substrate cleaning apparatus 51 of the first embodiment can accurately remove the objects 3 adhering to the surface of the substrate 1 .

[0089] The substrate cleaning device 51 of the first embodiment has a first spray unit movement function realized by the air knife movement mechanism 23M and a first spray angle adjustment function realized by the air knife rotation mechanism 23R.

[0090] Therefore, the substrate cleaning device 51 of embodiment 1 can adjust the confluence point of the relay mist gas MG1 and the air gas AG2 and the air gas spraying direction FG1 (= mist gas supply direction F23) so as to increase the effectiveness of removing the material 3 to be removed adhering to the surface of the substrate 1.

[0091] With respect to the mist ejection section 21 in the substrate cleaning apparatus 51 of the first embodiment, the mist gas ejection direction F21 includes a directional component in the table transport direction T2 (+X direction), and the mist supply angle A21, which is the mist ejection angle with respect to the table transport direction T2, is set in the range of 0 to 90 degrees (0 (degrees) < A21 < 90 (degrees)). On the other hand, with respect to the air knife 23, which is the first air gas blowing section, the air gas blowing direction FG1, which is the first air gas blowing direction, has a directional component in the opposite direction to the transport (-X direction), and the gas flow supply angle A23, which is the first air gas blowing angle, is set in the range of 0 to 90 degrees.

[0092] Therefore, the air knife 23 in the substrate cleaning apparatus 51 of the first embodiment can perform the first air gas spraying process on the relay mist gas MG1 ejected from the mist ejection part 21 relatively easily.

[0093] In a preferred aspect of this embodiment, the mist supply angle A21 is set in the range of 0 to 90 degrees, including a directional component of the table conveying direction T2, so that the mist is supplied to the air gas AG1 outlet or the vicinity of the outlet of the air knife 23. As a modified example, the mist supply angle A21 may be set to a value other than 0 to 90 degrees. As described above, the cleaning mist gas MG2 is significantly affected by the air gas AG1, so even in this modified example, it is possible to obtain cleaning mist gas MG2 that is sprayed directly onto the object 3 by the air gas AG1.

[0094] The substrate cleaning apparatus 51 of the first embodiment has a mist-jet-portion moving function by the mist-jet-portion moving mechanism 21M and a mist-jet-portion rotating mechanism 21R for adjusting the jet angle.

[0095] Therefore, the substrate cleaning device 51 of embodiment 1 can adjust the confluence point of the relay mist gas MG1 and the air gas AG2 so as to increase the effectiveness of removing the material 3 adhering to the surface of the substrate 1.

[0096] The mist diffusion prevention plate 4 in the substrate cleaning apparatus 51 of embodiment 1 is positioned so as to provide a diffusion suppression space S1 with a gap G4 that is a predetermined gap between the surface 1s of the substrate 1 and the mist diffusion prevention plate 4, without interfering with the supply of the cleaning mist gas MG2 to the surface 1s, which is the cleaning surface of the substrate 1.

[0097] The substrate cleaning apparatus 51 of embodiment 1 can exert a mist diffusion suppression effect that effectively suppresses the phenomenon of the cleaning liquid mist MT contained in the cleaning mist gas MG2 diffusing from the surface 1s of the substrate 1 by limiting the space in contact with the surface 1s of the substrate 1 to a relatively narrow diffusion suppression space S1 using the mist diffusion prevention plate 4.

[0098] Furthermore, when the air gas flow velocity VG1 of the air gas AG1 blown out from the air knife 23 is fast, the mist gas flow velocity V23 (=VG1) of the cleaning mist gas MG2 also becomes fast, making it difficult for the cleaning liquid mist MT in the cleaning mist gas MG2 to adhere to the surface 1s of the substrate 1. However, the cleaning liquid mist MT is present in the relatively narrow diffusion-suppressing space S1, and the mist diffusion suppression effect described above can increase the rate at which the cleaning liquid mist MT adheres to the surface 1s of the substrate 1.

[0099] As a result, the substrate cleaning device 51 of embodiment 1 can remove the object 3 to be removed without contaminating the surface 1s by preventing the surface 1s, which is the cleaning surface of the substrate 1, from drying and oxidizing due to the mist diffusion suppression effect.

[0100] In the substrate cleaning apparatus 51 of the first embodiment, a gap G4 (predetermined gap) is set to a length that exceeds the particle size of the cleaning liquid mist MT. In the first embodiment, the cleaning liquid mist MT is obtained by the ultrasonic atomizer 11, so the gap G4 is set to a length that exceeds 15 μm. This is because the particle size of the cleaning liquid mist MT generated by the ultrasonic atomizer 11 is 15 μm or less.

[0101] In order to prevent the mist diffusion suppression effect from being reduced, it is desirable to set the gap G4 within a range satisfying {15 μm<G4≦50 mm}. In other words, it is desirable to set the upper limit of the gap G4 to about 50 mm.

[0102] Therefore, the substrate cleaning apparatus 51 of the first embodiment can supply the cleaning liquid mist MT contained in the cleaning mist gas MG2 to the diffusion suppression space S1 of the relatively narrow gap G4 without any problems.

[0103] <Embodiment 2> Fig. 10 is an explanatory diagram that schematically shows the overall configuration of a substrate cleaning apparatus 52 according to embodiment 2. Fig. 11 is an explanatory diagram that schematically shows the configuration of a mist gas supply mechanism 20. An XYZ Cartesian coordinate system is depicted in each of Figs. 10 and 11.

[0104] Hereinafter, the same reference numerals will be used to designate the same components as those in the substrate cleaning device 51 of the first embodiment, and the description thereof will be omitted as appropriate, and the characteristic features of the substrate cleaning device 52 of the second embodiment will be described.

[0105] The transport means in the substrate cleaning device 52 of embodiment 2 includes a transport table 2B on which the substrate 1 is placed, as in embodiment 1, and performs the transport operation by moving the transport table 2B in the table transport direction T2.

[0106] The conveying table 2B has, in its upper portion, a suction mechanism 5 that suctions the rear surface 1r of the substrate 1. The substrate cleaning device 52 of the second embodiment is characterized by including the conveying table 2B having the suction mechanism 5.

[0107] 12 is an explanatory diagram schematically illustrating the structure of the suction mechanism 5. As shown in the figure, the suction mechanism 5 has a suction path 5r and a plurality of suction holes 5h that communicate with the suction path 5r. The plurality of suction holes 5h are arranged at positions that overlap with the rear surface of the substrate 1 in a plan view. The suction mechanism 5 has the suction path 5r and the plurality of suction holes 5h, and sucks the substrate 1 from the rear surface 1r through the plurality of suction holes 5h by vacuum suction.

[0108] In the substrate cleaning device 52 of embodiment 2, as in embodiment 1, the cleaning mist gas MG2 obtained by the first air gas spraying process of the air knife 23 is sprayed directly onto the surface of the substrate 1, so there is a possibility that the substrate 1 placed on the conveying table 2B will move.

[0109] In the substrate cleaning device 52 of embodiment 2, the conveying table 2B has an adsorption mechanism 5, and by using the adsorption mechanism 5 to adsorb the substrate 1 from the back surface 1r, the substrate 1 can be stably and tightly fixed on the conveying table 2 even when exposed to the cleaning mist gas MG2.

[0110] Furthermore, since the suction mechanism 5 functions as a porous suction plate having multiple suction holes 5h, even if the substrate 1 has a thin structure with a thickness of 1 mm or less, the substrate 1 can be tightly fixed on the conveying table 2 so that the substrate 1 does not move due to the cleaning mist gas MG2.

[0111] Furthermore, since the adsorption mechanism 5 functions as a porous adsorption plate, no gaps are generated between the surface of the adsorption mechanism 5 and the surface 1s of the substrate 1 due to deformation or deformation of the substrate 1 caused by concentrated adsorption in a localized area.

[0112] In this way, the substrate cleaning device 52 of embodiment 2 can reliably avoid deformation of the substrate 1, the occurrence of gaps, etc., and thereby reliably avoid the phenomenon of obstruction of the flow of the cleaning mist gas MG2 containing the cleaning liquid mist MT.

[0113] In the substrate cleaning apparatus 52 of the second embodiment, the suction mechanism 5 included in the conveying table 2B uses a plurality of suction holes 5h to suction the substrate 1 from the back surface 1r, so that the substrate 1 can be stably placed on the conveying table 2B when the cleaning mist gas MG2 or the air gas AG2 is sprayed directly onto the surface to be cleaned of the substrate 1. In this case, even if the thickness of the substrate 1 is 1 mm or less, the substrate 1 can be stably placed on the conveying table 2B.

[0114] Furthermore, since the plurality of suction holes 5h are provided so as to overlap on the rear surface of the substrate in plan view, the substrate 1 is not deformed when the suction mechanism 5 suctions the substrate 1. Therefore, no gap is generated between the suction mechanism 5 and the rear surface 1r of the substrate 1 due to deformation of the substrate 1.

[0115] As a result, the substrate cleaning device 52 of embodiment 2 can supply cleaning mist gas MG2 to the surface of the substrate 1 without any problems when performing the first air gas spraying process using the air knife 23, which is the first air gas spraying section, so that the object 3 to be removed adhering to the surface of the substrate 1 can be removed with high accuracy.

[0116] Furthermore, the substrate cleaning device 52 of embodiment 2 can supply air gas AG2 to the surface of the substrate 1 without any hindrance when performing the second air gas spraying process using the air knife 31, which is the second air gas spraying section, so that any residue remaining on the surface of the substrate 1 can be removed with high accuracy.

[0117] <Others> As described above, the substrate cleaning apparatus 51 of embodiment 1 and the substrate cleaning apparatus 52 of embodiment 2 have been shown as substrate cleaning apparatuses of the present disclosure, but the present disclosure is not limited to these embodiments and can be modified within the scope of the gist thereof.

[0118] In this embodiment, pure water is used as the cleaning liquid, but other possible cleaning liquids include alkaline degreasing liquids (solutions containing sodium hydroxide or phosphoric acid) and acidic degreasing liquids (solutions containing sulfuric acid or hydrochloric acid). The alkaline degreasing liquid and acidic degreasing liquid are effective cleaning liquids for the substrate 1 that requires degreasing treatment.

[0119] In addition, the substrate cleaning apparatus of the present disclosure can also be applied to an acid cleaning process using a solution containing sulfuric acid as the cleaning liquid, an etching process using a solution containing iron (III) chloride as the cleaning liquid, a surface modification process using a solution containing a metal organic compound such as TEOS as the cleaning liquid, and a resist agent removal process using a solution containing sodium hydroxide as the cleaning liquid.

[0120] In this embodiment, the object to be removed 3 is assumed to be a plating solution, but other possible objects to be removed 3 include solid fine particles such as dust, dirt, and particles, organic compounds such as oil, and metal / inorganic compounds such as rust and metal oxide films.

[0121] Furthermore, the plating removal products, typically from plating solutions, include metal salts, which are sources of metal ions, such as copper sulfate and nickel sulfate.

[0122] In the above-described embodiment, the mist gas supply mechanism 20 is configured with the mist ejection portion 21 and the air knife 23 which are independent of each other. However, it is also possible to adopt an embodiment in which the mist gas supply mechanism 20 and the mist ejection portion 21 are integrated together, as shown by the dashed line in Figure 6.

[0123] Furthermore, although the mist diffusion prevention plate 4 is disposed parallel to the table transport direction T2 (X direction), the present invention is not limited to this arrangement, and the arrangement direction of the mist diffusion prevention plate 4 may be significantly inclined with respect to the X direction. Furthermore, the shape of the mist diffusion prevention plate 4 is not limited to a flat plate shape.

[0124] The shape and arrangement of the mist diffusion prevention plate 4 can be set arbitrarily, provided that the mist diffusion prevention plate 4 can form a diffusion suppression space that can prevent the diffusion of the cleaning liquid mist MT contained in the cleaning mist gas MG2 in the spatial region in contact with the surface 1s, which is the cleaning surface of the substrate 1.

[0125] Furthermore, although the table transport direction T2, which is the transport direction of the substrate 1, is set to a horizontal direction along the X direction, the table transport direction T2 may be significantly inclined with respect to the X direction. Furthermore, the table transport direction T2 may be set to a vertical direction along the Z direction. In other words, the table transport direction T2 can be set arbitrarily, provided that the cleaning mist gas MG2 is sprayed onto the surface of the substrate 1 during the transport operation.

[0126] In the above-described embodiment, the cleaning surface of the substrate 1 is the front surface 1s, but the cleaning surface may be the back surface 1r. In this case, components corresponding to the mist gas supply mechanism 20 and the liquid draining mechanism 30 are disposed on the back surface 1r side of the substrate 1, and the cleaning mist gas is directly sprayed onto the back surface 1r of the substrate 1 by the first air gas blown out from the first air gas blowing unit corresponding to the air knife 23.

[0127] In the substrate cleaning device 52 of embodiment 2, the mode of tightly fixing the substrate 1 to the conveying table 2B may be such that a fixing means for the substrate 1 other than the adsorption mechanism 5 is provided under the condition that the substrate 1 is stably and tightly fixed on the conveying table 2B even when exposed to the cleaning mist gas MG2 or the air gas AG2 without impeding the flow of the cleaning mist gas MG2.

[0128] Although the present disclosure has been described in detail, the above description is illustrative in all respects and does not limit the present disclosure to the above. It is understood that countless variations not illustrated can be envisioned without departing from the scope of the present disclosure.

[0129] REFERENCE SIGNS LIST 1 substrate 2, 2B transport table 3 object to be removed 4 mist diffusion prevention plate 5 suction mechanism 5h suction hole 11 ultrasonic atomizer 12 mist supply piping 20 mist gas supply mechanism 21 mist jetting section 21M mist jetting section moving mechanism 21R mist jetting section rotation mechanism 23, 31 air knife 23M air knife moving mechanism 23R air knife rotation mechanism 30 liquid draining mechanism 51, 52 substrate cleaning device AG1, AG2 air gas MG1 relay mist gas MG2 cleaning mist gas MT cleaning liquid mist

Claims

1. A cleaning device comprising: a conveying means for performing a conveying operation of conveying a substrate along a conveying direction; and a mist gas supply mechanism for supplying a cleaning mist gas containing a cleaning liquid mist obtained by turning a cleaning liquid into a mist in order to clean a cleaning surface of the substrate, the mist gas supply mechanism including: a mist ejection section for ejecting a relay mist gas containing the cleaning liquid mist along a mist ejection direction; and a first air gas blowing section for performing a first air gas blowing process for blowing a first air gas along a first air gas blowing direction against the relay mist gas during a period in which the conveying operation is being performed by the conveying means, and merging the first air gas with the relay mist gas to obtain the cleaning mist gas, the cleaning mist gas being supplied to the cleaning surface of the substrate by the first air gas blowing process, a flow velocity of the relay mist gas is set to an initial mist flow velocity, and a flow velocity of the first air gas is set to a first air gas flow velocity, the first air gas flow velocity being set to a velocity higher than the initial mist flow velocity.

2. A substrate cleaning device according to claim 1, wherein the cleaning mist gas is directly sprayed onto the cleaning surface of the substrate by executing the first air gas spraying process of the first air gas spraying section.

3. A substrate cleaning device as described in claim 2, further comprising a second air gas spraying section that is disposed downstream of the first air gas spraying section in the conveying direction and that performs a second air gas spraying process of directly spraying a second air gas onto the cleaning surface of the substrate during the period in which the conveying operation is being performed by the conveying means.

4. A substrate cleaning apparatus as described in claim 2 or claim 3, further comprising: an ultrasonic atomizer that generates the cleaning liquid mist by applying ultrasonic vibrations to the cleaning liquid; and a mist supply pipe for supplying the cleaning liquid mist generated by the ultrasonic atomizer to the mist spraying portion.

5. A substrate cleaning device as described in any one of claims 1 to 4, wherein the first air gas spraying direction includes a component in a conveying counter direction that is the opposite direction to the conveying direction, and a first air gas spraying angle, which is the angle of the first air gas spraying direction with respect to the conveying direction, is set in a range greater than 0 degrees and less than 90 degrees.

6. A substrate cleaning device according to claim 5, comprising: a first spray section movement function for moving the first air gas spray section; and a first spray angle adjustment function for adjusting the first air gas spray angle.

7. A substrate cleaning device as described in claim 5 or claim 6, wherein the mist ejection direction includes a component of the transport direction, and a mist ejection angle, which is the angle of the mist ejection direction with respect to the transport direction, is set in the range of more than 0 degrees and less than 90 degrees.

8. A substrate cleaning device according to claim 7, comprising: a mist ejection part movement function for moving the mist ejection part; and a mist ejection angle adjustment function for adjusting the mist ejection angle.

9. A substrate cleaning apparatus as described in any one of claims 1 to 8, further comprising a mist diffusion prevention plate arranged between the mist gas supply mechanism and the cleaning surface of the substrate, the mist diffusion prevention plate being arranged so as to provide a diffusion suppression space of a predetermined gap between the cleaning surface of the substrate and the mist diffusion prevention plate without impeding the supply of the cleaning mist gas to the cleaning surface of the substrate.

10. The substrate cleaning device according to claim 9, wherein the predetermined gap is set to a length exceeding the particle size of the cleaning liquid mist.

11. A substrate cleaning apparatus as described in any one of claims 2 to 4, wherein the transport means includes a transport table on which the substrate is placed, and the transport operation is performed by moving the transport table in the transport direction, the transport table has an adsorption mechanism that adsorbs the back surface of the substrate, the adsorption mechanism has a plurality of suction holes that overlap the back surface of the substrate in a planar view, and the substrate cleaning apparatus adsorbs the back surface of the substrate using the plurality of suction holes.

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