JP2005277082A - Substrate washing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control properly the pushing load of a washing brush which acts on a substrate, and realize space saving. <P>SOLUTION: A front surface washing brush unit 33 equipped with a front surface washing brush 43, and a rear surface washing brush unit 34 equipped with a rear surface washing brush 44, are retained in a washing tank 31 through bearings so as to be capable of advancing and retreating with respect to a substrate 3. Then a front surface first link 48 to which the front surface washing brush unit is connected, and a rear surface first link 61 connected to the rear surface washing brush unit, are extended upward through the washing tank while the weight of a surface weight 50 acts on a front surface second link 49 connected to the front surface first link. The weight of the front surface weight is canceled by the weight of the front surface washing brush unit whereby the pushing load operated on the front surface of the substrate by the front surface washing brush is controlled. The weight of the rear surface weight 64 acts on the rear surface second link 62 connected to the rear surface first link, and the weight of the rear surface weight is canceled by the weight of the rear surface washing brush unit. Consequently, the pushing load can be controlled so that the rear surface washing brush acts on the rear surface of the substrate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a substrate cleaning apparatus, and more particularly to a substrate cleaning apparatus suitable for cleaning a substrate that requires a high degree of cleanliness, such as a semiconductor substrate.

  In recent years, with the progress of miniaturization of electronic devices, higher integration of semiconductor devices has progressed. As a result, even a small amount of impurities greatly affects the performance and yield of semiconductor devices. For this reason, very high cleanliness is required for the semiconductor substrate constituting the semiconductor device.

  A large amount of metal impurities contained in particles such as abrasives and chemicals, and metal ions and fine particles used for metal wiring on the semiconductor wafer adhere to the surface of the semiconductor wafer as a substrate processed by chemical mechanical polishing. doing. For this reason, it is necessary to clean this substrate, and so-called RCA cleaning is conventionally performed as this cleaning method. In this RCA cleaning, a first step of removing particles with an alkaline solution (ammonia-hydrogen peroxide solution) and a substrate treated in the first step are treated with an acid solution (DHF (dilute hydrofluoric acid) or the like). And a second step of removing metal impurities.

  This substrate cleaning process is performed, for example, by a substrate cleaning process and a substrate cleaning apparatus (see FIGS. 7 and 8) described in Patent Document 1.

  As shown in FIG. 7, the first step A is a step of removing particles adhering to the substrate 3 by washing while supplying the organic alkaline processing liquid to both the front and back surfaces of the substrate 3. As shown in FIG. 8, the substrate cleaning apparatus 1 used in the first step A has a pair of cleaning brushes 11 and 21 arranged corresponding to both the front and back surfaces of the substrate 3 and both the front and back surfaces of the substrate 3. On the other hand, it has a cleaning liquid supply nozzle 9 for supplying a cleaning liquid (in this case, an organic alkaline processing liquid), a driving roller 7 that holds and rotates the substrate 3, and a holding roller 6 that holds the substrate 3. The

  The driving roller 7 is connected to a driving force applying means (not shown), and can be rotated in the forward and reverse directions, for example, in the direction of arrow R (or the opposite direction), and the holding roller 6 is rotatable in the direction of arrow R and the opposite direction. Yes. The driving roller 7 and the holding roller 6 can be moved in the directions of arrows K and Q by a moving mechanism (not shown). Is carried in by the transfer device (not shown), the substrate 3 is moved in the direction of arrow Q to hold the substrate 3 in a predetermined position. In this state, the peripheral edge of the substrate 3 is engaged and held by the drive roller 7 and the holding roller 6, respectively.

  The cleaning brushes 11 and 21 are provided so as to be able to advance and retreat in the direction of arrow H (arrow Z) that approaches or separates from the front surface and the back surface of the substrate 3. When the substrate 3 is carried in by the transfer device, the cleaning brushes 11 and 21 are retracted from the substrate 3 upward and downward, respectively, and when the substrate 3 is held at a predetermined position, each moves forward and backward in the opposite direction. The substrate 3 comes into contact with the front and back surfaces, respectively. Further, the cleaning brushes 11 and 21 are connected to a drive mechanism (not shown), and are driven to rotate in opposite directions (arrow S and arrow T directions). The cleaning brushes 11 and 21 have shaft portions 11a and 21a covered with porous sponge members, for example, brush portions 11b and 21b made of PVA (polyvinyl alcohol) or the like, and a large number of convex portions 11c on the surfaces of the brush portions 11b and 21b. , 21c are formed.

  Therefore, the drive roller 7 is rotated in the direction of arrow R (or the reverse direction) by the drive force applying means (not shown), so that the substrate 3 is rotationally driven in the direction of arrow V (or the reverse direction). Then, a cleaning liquid (in this case, an organic alkaline processing liquid) is dropped from the cleaning liquid supply nozzle 9 and the cleaning brushes 11 and 21 are rotationally driven in opposite directions (arrow S and arrow T directions), whereby the front and back surfaces of the substrate 3 are recovered. Comes into contact with the convex portions 11c and 21c of the cleaning brushes 11 and 21, respectively, and is cleaned. When the cleaning with the organic alkaline processing liquid is completed, pure water is supplied to both the front and back surfaces of the substrate 3, and the cleaning liquid remaining on the substrate 3 and particles detached from the substrate 3 are cleaned.

  When the processing of the first step A is completed, the substrate 3 is unloaded by a transfer device (not shown) and transferred toward the second step B. The operation of the substrate cleaning apparatus 1 when unloading the substrate 3 is the reverse of the operation at the time of loading, and the basic operation is the same, so the description is omitted.

  As shown in FIG. 7, the second step B is a step of removing metal impurities adhering to the surface of the substrate 3 by washing while supplying the organic acidic treatment liquid to both the front and back surfaces of the substrate 3. Note that the second step B is different only in the cleaning liquid (in this case, the organic acid processing liquid) used in the first step A, and the configuration and operation of the substrate cleaning apparatus 1 are the same. Is omitted.

  In the third step C in FIG. 7, pure water is supplied to the surface of the substrate 3 processed in the second step B to form a liquid film, and a high oxidizing power processing solution is supplied to the back surface of the substrate 3. In this step, the substrate 3 is washed while rotating. Moreover, the 4th process D in FIG. 7 is a process of performing spin drying after implementing ultrasonic cleaning to the board | substrate 3 processed at the 3rd process C. In FIG.

  Incidentally, although not shown, Patent Document 2 discloses a substrate cleaning apparatus that adjusts the pressing load acting on the cleaning brush substrate 3 by the balance between the weight of the cleaning brush and the weight of the weight. In the apparatus described in Patent Document 2, a fulcrum is provided in the brush holding mechanism, a cleaning brush is attached to one end of the fulcrum, a weight is movably attached to the other end of the fulcrum, and the position of the weight is changed. Thus, the pressing load is adjusted.

JP 2002-299300 A Japanese Patent Laid-Open No. 57-102024

  However, in the substrate cleaning apparatus described in Patent Document 1, the positions at which the cleaning brushes 11 and 21 contact the substrate 3 are set based on the positions at which the cleaning brushes 11 and 21 contact the substrate 3 (hereinafter referred to as zero points). The cleaning brush 11 is moved downward and the cleaning brush 21 is moved upward by a predetermined amount. This moving amount generates a pressing load in which the cleaning brushes 11 and 21 act on the front surface and the back surface of the substrate 3, respectively, and exerts a cleaning effect. As a result, there were variations due to individual differences among workers.

  Further, after the cleaning brushes 11 and 21 are aligned, the stop positions of the cleaning brushes 11 and 21 are fixed. Therefore, if the cleaning brushes 11 and 21 are decentered, the amount of eccentricity and variations thereof During the rotation of the cleaning brushes 11 and 21, the pressing load applied to the substrate 3 by the cleaning brushes 11 and 21 may fluctuate, which may cause a large variation in the cleaning effect.

  Further, the substrate cleaning apparatus described in Patent Document 2 has a problem that the entire structure including the brush holding mechanism and the weight becomes complicated and the installation space of the apparatus becomes large.

  An object of the present invention is to provide a substrate cleaning apparatus capable of appropriately managing the pressing load of a cleaning brush that acts on a substrate and realizing space saving. .

  The invention described in claim 1 is a substrate cleaning apparatus for cleaning the substrate by pressing and rotating the cleaning brush against the substrate in the cleaning tank, and the cleaning brush is provided in the cleaning tank. A cleaning brush unit is pivotally supported relative to the substrate, a first link connected to the cleaning brush unit extends upward through the cleaning tank, and a second link connected to the first link The weight of the weight acts on the second link, and the weight of the weight is transmitted to the cleaning brush unit via the first link and is offset with the weight of the cleaning brush unit. Thus, the cleaning brush is configured to adjust a pressing load acting on the substrate.

  According to a second aspect of the present invention, in the first aspect of the present invention, when an operating force acts on the second link from an actuator, the first link is raised or lowered to rotate the cleaning brush unit, A cleaning brush retracting mechanism for retracting the cleaning brush of the cleaning brush unit from the substrate is provided, and the actuator is disposed with a gap with respect to the second link when not operating.

  According to a third aspect of the present invention, in the first aspect of the present invention, the cleaning brush unit includes a front surface cleaning brush unit having a front surface cleaning brush for cleaning the surface of the substrate, and a rear surface for cleaning the rear surface of the substrate. A back surface cleaning brush unit having a cleaning brush, wherein the weight of the surface cleaning brush unit is offset with the weight of the surface weight transmitted to the surface cleaning brush unit via the surface second link and the surface first link. Thus, the pressing load that the front surface cleaning brush acts on the substrate is adjusted, and the weight of the rear surface cleaning brush unit is transmitted to the rear surface cleaning brush unit via the rear surface second link and the rear surface first link. The backside cleaning brush is configured to adjust the pressing load acting on the substrate by offsetting the weight of the weight. Is shall.

  The invention according to claim 4 is the invention according to claim 2, wherein the cleaning brush retracting mechanism includes a surface cleaning brush retracting mechanism for retracting the surface cleaning brush from the substrate by an operating force from the surface actuator, and a back surface actuator. It is a back surface cleaning brush retracting mechanism that retracts the back surface cleaning brush from the substrate by an operating force from the above.

  The invention according to claim 5 is the surface cylinder device according to claim 4, wherein the surface actuator is provided with a stopper having a U-shaped cross section at the tip of the piston rod, and the stopper is the surface cylinder. When the apparatus is not operated, the connecting rod that connects the front surface second link and the front surface first link is disposed with a gap. When the device is not operated, the tip of the piston rod is connected to the back surface second link. On the other hand, the back surface cylinder device is arranged with a gap.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the pressing load applied to the substrate by the cleaning brush is 50 to 200 gf.

  According to the invention described in claim 1 or 6, the weight of the cleaning brush unit and the weight of the weight are offset so that the pressing load applied to the substrate by the cleaning brush of the cleaning brush unit is adjusted. Therefore, since an appropriate pressing load can be easily set by changing the weight of the weight, the pressing load can be appropriately managed, and as a result, the cleaning of the substrate with the cleaning brush can be realized stably.

  Also, the offset of the weight of the cleaning brush unit and the weight of the weight determines the pressing load that the cleaning brush of the cleaning brush unit acts on the substrate, and the position of the cleaning brush relative to the substrate is determined by this pressing load. Even when the shaft is eccentric, the cleaning brush moves up and down by the amount corresponding to the amount of eccentricity, and the pressing load can be kept constant. For this reason, the cleaning of the substrate by the cleaning brush can be stabilized without being affected by the eccentricity of the cleaning brush.

  Furthermore, since the position of the cleaning brush relative to the substrate is determined by the pressing load applied to the substrate by the cleaning brush, an operation for setting the position of the cleaning brush by the operator becomes unnecessary. Therefore, it is possible to avoid a situation where the position of the cleaning brush varies due to individual differences among workers and the pressing load fluctuates and the substrate cleaning becomes unstable.

  Further, since the pressing load adjusting mechanism including the first link, the second link and the weight is disposed above the cleaning tank, the substrate is compared with the case where the pressing load adjusting mechanism is disposed on the side of the cleaning tank. Space saving of the installation area of the cleaning device can be realized. For this reason, it is possible to facilitate the layout of the transfer apparatus that carries the substrate in and out of the cleaning tank of the substrate cleaning apparatus.

  In addition, since the cleaning tank is only provided with a through-opening through which the first link passes, sealing this through-opening prevents the cleaning liquid and the like from splashing out of the cleaning tank when cleaning the substrate in the cleaning tank. Can be prevented.

  According to the second aspect of the present invention, when the operating force is applied to the second link from the actuator, the first link is raised or lowered to rotate the washing brush unit. Since the cleaning brush retracting mechanism for retracting from the substrate is provided, the substrate can be preferably carried in and out by retracting the cleaning brush from the substrate when the substrate is carried in and out.

  According to the third aspect of the present invention, the pressing load applied to the substrate by the front surface cleaning brush and the pressing load applied to the substrate from the rear surface cleaning brush change the respective weights of the front surface weight and the back surface weight. Since the adjustment is performed independently, the respective pressing loads can be set optimally according to the size of the substrate, the type of cleaning liquid, the material of the cleaning brush, and the like.

  According to the invention described in claim 4 or 5, the front surface cleaning brush retracting mechanism for retracting the front surface cleaning brush from the substrate and the rear surface cleaning brush retracting mechanism for retracting the rear surface cleaning brush from the substrate are installed independently. Therefore, the retreating operation for retracting the front surface cleaning brush and the back surface cleaning brush from the substrate can be performed independently, so that the retreating movement amount of the front surface cleaning brush and the retreating movement amount of the back surface cleaning brush can be optimally set individually.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic sectional side view showing an embodiment of a substrate cleaning apparatus according to the present invention. FIG. 2 is a sectional view taken along line II-II in FIG.

  A substrate cleaning apparatus 30 shown in FIG. 1 includes a substrate holding and rotating device 32, a front surface cleaning brush unit 33, a back surface cleaning brush unit 34, and a cleaning liquid supply nozzle 35 disposed in a cleaning tank 31. The pressing load adjusting mechanism 36, the back pressing load adjusting mechanism 37, the front surface cleaning brush retracting mechanism 38, and the back surface cleaning brush retracting mechanism 39 are arranged.

  The substrate holding / rotating device 32 includes a plurality of holding rollers 40 and a driving roller 41, and these hold the peripheral edge of the substrate 3. Among these, the holding roller 40 is rotatably provided, and the driving roller 41 is rotationally driven to apply a rotational force to the substrate 3 to rotate the substrate 3 within the horizontal plane. The holding roller 40 and the driving roller 41 are separated from the peripheral edge of the substrate 3 to allow the substrate 3 to be transferred into and out of the cleaning tank 31, and approach the peripheral edge of the substrate 3 after the substrate 3 is transferred. And the peripheral edge part of this board | substrate 3 is hold | maintained. The substrate 3 is carried into or out of the cleaning tank 31 by opening a carry-in / out door 63 provided on the side of the cleaning tank 31 by a transfer device (not shown).

  The surface cleaning brush unit 33 is disposed above the substrate holding and rotating device 32 in the cleaning tank 31, and the surface cleaning brush 43 for cleaning the surface of the substrate 3 on the surface unit frame 42 having a U-shaped cross section shown in FIG. Is rotatably supported, and a drive source (not shown) for rotationally driving the surface cleaning brush 43 is installed inside the surface unit frame 42. Further, the surface unit frame 42 is pivotally supported with respect to the cleaning tank 31 by a pivot shaft 45 shown in FIG. Accordingly, the surface cleaning brush 43 of the surface cleaning brush unit 33 advances to approach the surface of the substrate 3 or retracts to separate from the surface of the substrate 3.

  The back surface cleaning brush unit 34 is disposed below the substrate holding and rotating device 32 in the cleaning tank 31, and back surface cleaning brush 44 for cleaning the back surface of the substrate 3 on the back surface unit frame 46 having a U-shaped cross section shown in FIG. 2. Is rotatably supported, and a drive source (not shown) for rotationally driving the back surface cleaning brush 44 is installed inside the back surface unit frame 46. Further, the back unit frame 46 is pivotally supported with respect to the cleaning tank 31 by a pivot shaft 47 shown in FIG. Accordingly, the back surface cleaning brush 44 of the back surface cleaning brush unit 34 advances to approach the back surface of the substrate 3 or retracts to separate from the back surface of the substrate 3.

  Here, the front surface cleaning brush 43 and the rear surface cleaning brush 44 are rotationally driven in opposite directions. Further, as shown in FIG. 2, the front surface cleaning brush 43 and the rear surface cleaning brush 44 have a shaft portion 27 covered with a brush portion 28 made of a porous sponge member, for example, PVA (polyvinyl alcohol). A large number of convex portions 29 are formed on the surface of the brush portion 28.

  As shown in FIG. 1, in a state where the driving roller 41 of the substrate holding and rotating device 32 is driven and the substrate 3 is rotated in the horizontal plane, the cleaning liquid is supplied from the cleaning liquid supply nozzle 35 to the front and back surfaces of the substrate 3. In this state, the convex portion 29 of the front surface cleaning brush 43 is pressed against the surface of the substrate 3 and rotated to clean the surface of the substrate 3, and the convex portion 29 of the back surface cleaning brush 44 is pressed against the rear surface of the substrate 3. By rotating, the back surface of the substrate 3 is cleaned.

  The surface pressing load adjusting mechanism 36 includes a first surface link 48, a second surface link 49, and a surface weight 50, and is supported by a support frame 51 provided on the outer upper side of the cleaning tank 31. .

  As shown in FIGS. 2 and 3, a pair of the first surface links 48 is provided, and lower ends of the first surface links 48 are rotatably supported on the surface unit frame 42 of the surface cleaning brush unit 33 by using the shaft support pins 52. The Further, a pair of the surface second links 49 are provided, and the distal end portions thereof are integrated by the connecting rod 53, and the proximal end portion is pivotally supported by the support frame 51 using the pivot shaft 54. The Further, the first surface link 48 passes through a through opening 55 formed in the ceiling portion of the cleaning tank 31 and extends upward of the cleaning tank 31, and an upper end portion thereof is rotatably connected to and supported by the connecting rod 53.

  One end of a wire rope 56 is fixed to the connecting rod 53 of the surface second link 49, the wire rope 56 is wound around a plurality of pulleys 57 supported by a support frame 51, and the surface weight 50 is connected to the other end. Is fixed. Accordingly, the weight of the surface weight 50 acts on the surface second link 49 to rotate the surface second link 49 upward, and acts on the surface first link 48 to cause the surface first link 48 to move. It is moved upward and transmitted to the surface cleaning brush unit 33. Thereby, the weight of the surface cleaning brush unit 33 is offset with the weight of the surface weight 50, and the surface cleaning brush 43 of the surface cleaning brush unit 33 is pressed against the surface of the substrate 3 by changing the weight of the surface weight 50. The load is adjusted.

The pressing load on the surface of the substrate 3 by the surface pressing load adjusting mechanism 36 will be described with reference to FIG. A load acting on the pivot pin 52 due to a moment around the pivot axis 45 of the weight of the surface cleaning brush unit 33 is defined as w ₁ . Further, the load acting on the connecting rod 53 due to a moment about the pivot axis 54 of the weight of the surface the second link 49 and w _2. If the weight of the surface first link 48 and the wire rope 56 is ignored and the weight of the surface weight 50 is W, and the surface cleaning brush 43 is balanced without contacting the surface of the substrate 3, the balance formula is w ₁ + w ₂ = W
It is represented by

The balance formula when the weight of the surface weight 50 is changed to W ′ and the surface cleaning brush 43 applies the pressing load F to the surface of the substrate 3 is:
w ₁ + w ₂ = W ′ + (m / L) × F
It becomes. Here, L is the dimension between the pivot shaft 45 and the pivot pin 52, and m is the dimension between the point of action of the pressing load F and the pivot shaft 45. Therefore, the pressing load F that the surface cleaning brush 43 acts on the surface of the substrate 3 is F = (L / m) × (w ₁ + w ₂ −W ′).
And erase the loads W ₁ and W ₂ ,
F = (L / m) × (W−W ′)
It becomes. Since L and m are constant values, the pressing load F applied to the surface of the substrate 3 by the surface cleaning brush 43 is uniquely determined by a decrease from the load W of the surface weight 50.

  As shown in FIGS. 2 and 3, the surface cleaning brush retracting mechanism 38 retracts the surface cleaning brush 43 of the surface cleaning brush unit 33 from the surface of the substrate 3 by an operating force from the surface cylinder device 58 as a surface actuator. It is something to be made. The surface cylinder device 58 is installed on the support frame 51 and includes a stopper 60 having a U-shaped cross section at the tip of the piston rod 59. The connecting rod 53 of the surface second link 49 is disposed in the stopper 60. The surface cylinder device 58 pushes out the piston rod 59 when not operating, and pulls back the piston rod 59 when operating. The stopper 60 of the piston rod 59 has a gap e1 between it and the connecting rod 53 of the surface second link 49 in the surface pressing load adjusting mechanism 36 when the surface cylinder device 58 is not operated. The structure is supported only by the weight of the surface weight 50 via the connecting rod 53 and the wire rope 56 of the first surface link 48 and the second surface link 49.

  When the surface cylinder device 58 is operated, the piston rod 59 is pulled back, the stopper 60 comes into contact with the connecting rod 53, the surface second link 49 is rotated upward, and the surface first link 48 is pulled upward. The surface cleaning brush unit 33 is lifted by the operating force of the surface cylinder device 58. As a result, the surface cleaning brush 43 of the surface cleaning brush unit 33 is separated from the surface of the substrate 3 and retracted from the substrate 3 so that the substrate 3 can be carried in and out.

  On the other hand, as shown in FIG. 1, the back surface pressing load adjusting mechanism 37 includes a back surface first link 61, a back surface second link 62, and a back surface weight 64, and is supported by the support frame 51.

  The back surface first link 61 is provided in a pair, and the lower end portions of the back surface first link 61 can be freely rotated by using a shaft support pin 65 on the back surface unit frame 46 of the back surface cleaning brush unit 34 having a U-shaped cross section shown in FIGS. It is pivotally supported. Further, a pair of the back surface second links 62 are provided, and the distal end portions thereof are integrated by the connecting rod 66, and the proximal end portion is pivotally supported by the support frame 51 using the pivot shaft 67. The Further, the first back link 61 extends through the through opening 68 formed in the ceiling portion of the cleaning tank 31 and extends above the cleaning tank 31, and the upper end portion thereof is rotatably connected to the connecting rod 66.

  A seal 69 is applied to the through opening 68 through which the first back link 61 passes and the through opening 55 (FIG. 1) through which the first front link 48 passes. This prevents the cleaning liquid or the like in the cleaning tank 31 from splashing outside when the substrate 3 is cleaned.

  One end of a wire rope 70 is fixed at a substantially central position in the longitudinal direction of the second back link 62 shown in FIG. 4, and this wire rope 70 is wound around a plurality of pulleys 71 supported by a support frame 51 and the other end. The back surface weight 64 is fixed to the surface. Accordingly, the weight of the back surface weight 64 acts on the back surface second link 62 to rotate the back surface second link 62 upward, and acts on the back surface first link 61 to cause the back surface first link 61 to move. It is moved upward and transmitted to the back surface cleaning brush unit 34. Accordingly, the weight of the back surface cleaning brush unit 34 is offset with the weight of the back surface weight 64, and the back surface cleaning brush 44 of the back surface cleaning brush unit 34 is pressed against the back surface of the substrate 3 by changing the weight of the back surface weight 64. The load is adjusted.

The pressing load on the back surface of the substrate 3 by the back surface pressing load adjusting mechanism 37 will be described with reference to FIG. The load acting on the shaft supporting pin 65 due to a moment about the pivot axis 47 of the weight of the back surface cleaning brush unit 34 and z _1. Further, the load acting on the pivot shaft 67 connecting rod 66 due to a moment about the weight of the back surface second link 62 and z _2. Neglecting the weight of the first back surface link 61 and the wire rope 70 and assuming the weight of the back surface weight 64 to be Z, the back surface cleaning brush 44 of the back surface cleaning brush unit 34 is balanced without contacting the back surface of the substrate 3. In this case, when the balance equation is considered by the moment of the pivot shaft 67,
(Z ₁ + z ₂ ) × L ₂ = Z × t
It can be expressed as

The balance formula in the state where the weight of the back surface weight 64 is changed to Z ′ and the back surface cleaning brush 44 is in contact with the back surface of the substrate 3 and the pressing load P is applied to the back surface is (z ₁ + z ₂ + P × s / L _1). ) × L ₂ = Z ′ × t
It becomes. When the loads z ₁ and z ₂ are erased and arranged, the pressing load P applied to the back surface of the substrate 3 by the back surface cleaning brush 44 is:
P = (Z′−Z) × (L ₁ / s) × (t / L ₂ )
It becomes. Here, L ₁ is the dimension between the pivot shaft 47 and the pivot pin 65, s is the dimension between the point of action of the pressing load P and the pivot shaft 47, and L ₂ is the dimension between the pivot shaft 67 and the connecting rod 66. , T is the dimension between the point of application of the weight of the back surface weight 64 to the back surface second link 62 and the pivot shaft 67, both of which are constant values. Therefore, the pressing load P applied to the back surface of the substrate 3 by the back surface cleaning brush 44 is uniquely determined by the increase in the weight Z of the back surface weight 64.

  As shown in FIG. 4, the back surface cleaning brush retracting mechanism 39 retracts the back surface cleaning brush 44 of the back surface cleaning brush unit 34 from the back surface of the substrate 3 by an operating force from the back surface cylinder device 72 as a back surface actuator. is there. The back cylinder device 72 is installed on the support frame 51 and includes a nose block 74 at the tip of the piston rod 73. The back surface cylinder device 72 pushes out the piston rod 73 when operated, and pulls back the piston rod 73 when not operated. The nose block 74 has a gap e2 between the back surface second load link 62 in the back surface pressing load adjusting mechanism 37 when the back surface cylinder device 72 is not in operation, and the back surface cleaning brush unit 34 is connected to the back surface first link 61 and the back surface first link. The structure is supported only by the weight of the back surface weight 64 via the two links 62 and the wire rope 70.

  When the back cylinder device 72 is operated, the piston rod 73 is pushed out so that the nose block 74 contacts the back second link 62 and rotates the back second link 62 downward, while the back first link 61 moves downward. The back surface cleaning brush unit 34 is rotated downward by the operating force and its own weight of the back surface cylinder device 72. Thereby, the back surface cleaning brush 44 of the back surface cleaning brush unit 34 is separated from the back surface of the substrate 3 and retracted from the substrate 3, and the substrate 3 can be carried in and out.

  Here, the pressing load that the surface cleaning brush 43 acts on the surface of the substrate 3 and the pressing load that the back surface cleaning brush 44 acts on the back surface of the substrate 3 are set in the range of 50 to 200 gf. Note that 1 gf corresponds to approximately 9.8 mN in SI units.

  For example, as shown in FIG. 6, the pressing load that the back surface cleaning brush 44 acts on the back surface of the substrate 3 is set to 100 gf, and the pressing load that the surface cleaning brush unit 33 acts on the surface of the substrate 3 is increased by 50 gf from 0 to 250 gf. Let At this time, the number of particles having a diameter of 0, 12 μm or more remaining on the substrate 3 before and after cleaning is the smallest when the pressing load by the surface cleaning brush unit 33 is in the range of 50 to 200 gf. Therefore, it can be seen that the pressing effect by the front surface cleaning brush 43 and the rear surface cleaning brush 44 has a remarkable cleaning effect in the range of 50 to 200 gf.

  With the configuration as described above, the following effects (1) to (8) are achieved according to the above embodiment.

  (1) Since the weight of the surface cleaning brush unit 33 and the weight of the surface weight 50 are offset, the pressing load applied to the surface of the substrate 3 by the surface cleaning brush 43 of the surface cleaning brush unit 33 is adjusted. Since the weight of the back surface cleaning brush unit 34 and the weight of the back surface weight 64 are offset, the pressing load that the back surface cleaning brush 44 of the back surface cleaning brush unit 34 acts on the back surface of the substrate 3 is adjusted. 50, since the appropriate pressing load can be easily set by changing the weight of each of the back surface weights 64, the pressing load can be appropriately managed. As a result, the substrate 3 is cleaned by the front surface cleaning brush 43 and the back surface cleaning brush 44. Cleaning can be realized stably.

  (2) By the offset between the weight of the surface cleaning brush unit 33 and the weight of the surface weight 50, the pressing load acting on the surface of the substrate 3 by the surface cleaning brush 43 of the surface cleaning brush unit 33 is determined, and the surface cleaning is performed by this pressing load. The position of the brush 43 with respect to the substrate is determined, and the back surface cleaning brush 44 of the back surface cleaning brush unit 34 is pressed against the back surface of the substrate 3 by offsetting the weight of the back surface cleaning brush unit 34 and the weight of the back surface weight 64. Since the load is determined and the position of the back surface cleaning brush 44 relative to the substrate is determined by this pressing load, even when the surface cleaning brush 43 and the back surface cleaning brush 44 are eccentric, the surface cleaning brush is equivalent to the amount of eccentricity. 43, the back surface cleaning brush 44 moves up and down, and the pressing load can be kept constant. For this reason, the cleaning of the substrate 3 by the front surface cleaning brush 43 and the back surface cleaning brush 44 can be stabilized without being affected by the eccentricity of the front surface cleaning brush 43 and the back surface cleaning brush 44.

  (3) The position of the front surface cleaning brush 43 with respect to the substrate 3 is determined by the pressing load that the front surface cleaning brush 43 acts on the substrate 3, and the rear surface cleaning brush 44 acts on the substrate 3 by the pressing load that acts on the substrate 3. Since the position with respect to the substrate 3 is determined, there is no need for the operator to set the positions of the front surface cleaning brush 43 and the rear surface cleaning brush 44. Therefore, it is possible to avoid a situation in which the pressing load varies and the cleaning of the substrate 3 becomes unstable due to variations in position setting of the front surface cleaning brush 43 and the rear surface cleaning brush 44 due to individual differences among workers.

  (4) Above the cleaning tank 31, the surface pressing load adjusting mechanism 36 including the first surface link 48, the second surface link 49, and the front surface weight 50, the back surface first link 61, the back surface second link 62, and the back surface weight. Since the back surface pressing load adjusting mechanism 37 having 64, the front surface cleaning brush retracting mechanism 38 having the front surface cylinder device 58, and the back surface cleaning brush retracting mechanism 39 having the back surface cylinder device 72 are respectively disposed. Compared with the case where the front surface pressing load adjusting mechanism 36, the back surface pressing load adjusting mechanism 37, the front surface cleaning brush retracting mechanism 38, and the back surface cleaning brush retracting mechanism 39 are arranged on the side of the cleaning tank 31, the installation area of the substrate cleaning device 30 is reduced. Space saving can be realized. For this reason, the layout of the transfer device (not shown) for carrying the substrate in and out of the cleaning tank 31 of the substrate cleaning device 30 can be facilitated.

  (5) Since the cleaning tank 31 is only provided with a through-opening 55 through which the front surface first link 48 penetrates and a through-opening 68 through which the back surface first link 61 penetrates, these through-openings 55, 68 are provided in the seal 69. Thus, when the substrate is cleaned in the cleaning tank 31, it is possible to prevent the cleaning liquid and the like from scattering into the cleaning tank 31 in combination with the closing of the carry-in / out door 63.

  (6) When the operating force acts on the surface second link 49 from the surface cylinder device 58, the surface first link 48 is raised to rotate the surface cleaning brush unit 33 upward. When the operating force is applied from the back surface cylinder device 72 to the front surface cleaning brush retracting mechanism 38 that retracts from the substrate 3 and the back surface second link 62, the back surface first link 61 is lowered to rotate the back surface cleaning brush unit 34 downward. The back surface cleaning brush retracting mechanism 39 for retracting the back surface cleaning brush 44 of the back surface cleaning brush unit 34 from the substrate 3 is provided, so that the front surface cleaning brush 43 and the back surface cleaning brush 44 are attached to the substrate 3 when the substrate 3 is carried in and out. The substrate 3 can be carried in and out suitably by retracting from the position.

  (7) The pressing load that the front surface cleaning brush 43 acts on the surface of the substrate 3 and the pressing load that the rear surface cleaning brush 44 acts on the back surface of the substrate 3 change the weights of the front surface weight 50 and the back surface weight 64. Therefore, the respective pressing loads can be optimally set individually according to the size of the substrate 3, the type of the cleaning liquid, the material of the cleaning brush, and the like.

  (8) Since the front surface cleaning brush retracting mechanism 38 for retracting the front surface cleaning brush 43 from the substrate 3 and the rear surface cleaning brush retracting mechanism 39 for retracting the rear surface cleaning brush 44 from the substrate 3 are provided independently, Since the retracting operation for retracting the brush 43 and the back surface cleaning brush 44 from the substrate 3 can be performed independently, the retracting movement amount of the front surface cleaning brush 43 and the retracting movement amount of the back surface cleaning brush 44 can be set optimally individually.

  As mentioned above, although this invention was demonstrated based on the said embodiment, this invention is not limited to this. For example, in the above embodiment, the actuator for the front surface cleaning brush retracting mechanism 38 and the back surface cleaning brush retracting mechanism 39 is a cylinder device. However, the plunger is advanced and retracted using a solenoid, and the electric motor and screw mechanism are combined. The rod may be advanced and retracted.

It is a schematic sectional side view which shows one Embodiment of the substrate cleaning apparatus which concerns on this invention. It is sectional drawing which follows the II-II line of FIG. It is an expanded sectional view which shows the surface cleaning brush unit of FIG. 1, a surface pressing load adjustment mechanism, and a surface cleaning brush retracting mechanism. It is an expanded sectional view which shows the back surface cleaning brush unit of FIG. 1, a back surface pressing load adjustment mechanism, and a back surface cleaning brush retracting mechanism. FIG. 5A is a diagram schematically illustrating the relationship between power point action points by simplifying the mechanisms shown in FIG. 3 and FIG. 4B simplifying the mechanisms shown in FIG. 4. The substrate cleaning effect when the pressing load is changed is shown, (A) is a chart showing actual measurement data, and (B) is a graph showing the cleaning effect. It is a block diagram which shows the conventional board | substrate cleaning process. It is a perspective view which shows the board | substrate cleaning apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Substrate 30 Substrate cleaning device 31 Cleaning tank 33 Front surface cleaning brush unit 34 Back surface cleaning brush unit 36 Front surface pressing load adjustment mechanism 37 Back surface pressing load adjustment mechanism 38 Front surface cleaning brush retracting mechanism 39 Back surface cleaning brush retracting mechanism 43 Front surface cleaning brush 44 Back surface cleaning Brush 48 Surface first link 49 Surface second link 50 Surface weight 53 Connecting rod 55 Through opening 56 Wire rope 58 Surface cylinder device 59 Piston rod 60 Stopper 61 Back surface first link 62 Back surface second link 64 Back surface weight 68 Through opening 69 Seal 70 Wire rope 72 Backside cylinder device 73 Piston rod e1, e2 Clearance

Claims (6)

A substrate cleaning apparatus for cleaning the substrate by pressing and rotating a cleaning brush against the substrate in a cleaning tank,
In the cleaning tank, a cleaning brush unit provided with the cleaning brush is pivotally supported so as to advance and retreat with respect to the substrate.
A first link connected to the cleaning brush unit extends upward through the cleaning tank, and a second link connected to the first link is rotatably provided.
The weight of the weight acts on the second link, and the weight of the weight is transmitted to the cleaning brush unit via the first link, and is canceled with the weight of the cleaning brush unit. A substrate cleaning apparatus configured to adjust a pressing load acting on a substrate.   When the operating force is applied to the second link from the actuator, the first brush is raised or lowered to rotate the cleaning brush unit, and the cleaning brush retracting mechanism for retracting the cleaning brush of the cleaning brush unit from the substrate is provided. 2. The substrate cleaning apparatus according to claim 1, wherein the actuator is disposed with a gap with respect to the second link when not operating. The cleaning brush unit is a surface cleaning brush unit provided with a surface cleaning brush for cleaning the surface of the substrate, and a back surface cleaning brush unit provided with a back surface cleaning brush for cleaning the back surface of the substrate,
The weight of the surface cleaning brush unit is canceled by the weight of the surface weight transmitted to the surface cleaning brush unit via the surface second link and the surface first link, so that the surface cleaning brush acts on the substrate. The pressing load to be adjusted
The weight of the back surface cleaning brush unit cancels the weight of the back surface weight transmitted to the back surface cleaning brush unit via the back surface second link and the back surface first link, so that the back surface cleaning brush acts on the substrate. The substrate cleaning apparatus according to claim 1, wherein the pressing load to be adjusted is adjusted.   The cleaning brush retracting mechanism includes a front surface cleaning brush retracting mechanism that retracts the front surface cleaning brush from the substrate by operating force from the front surface actuator, and a back surface cleaning brush that retracts the back surface cleaning brush from the substrate by operating force from the back surface actuator. The substrate cleaning apparatus according to claim 2, wherein the substrate cleaning apparatus is a retraction mechanism. The surface actuator is a surface cylinder device having a U-shaped stopper at the tip of the piston rod, and the stopper connects the surface second link and the surface first link when the surface cylinder device is not in operation. Arranged with a gap to the connecting rod
5. The substrate cleaning apparatus according to claim 4, wherein the back surface actuator is a back surface cylinder device in which a tip end of a piston rod is disposed with a gap with respect to the back surface second link when not operating. 6. The substrate cleaning apparatus according to claim 1, wherein a pressing load applied to the substrate by the cleaning brush is 50 to 200 gf.

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