JP5297268B2 - How to arrange fine particles - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method such that workpieces provided with conductive balls can be manufactured in good yield in which minute particles of solder balls, gold balls, copper balls or the like, used in mounting a semiconductor device or an optical device on a substrate, are arranged accurately and highly reliably with respect to workpieces such as wafers etc. in accordance with a desired pattern. <P>SOLUTION: A mask 45 includes a pattern of openings 46 for arranging conductive balls 48 in given positions of a wafer 10. The method has steps of: positionally matching a mask 45 and the wafer 10; filling the conductive balls 48 in a pattern of openings 46 of the mask 45; and removing the conductive balls 48d, which are packed in the opening patterns 46 of the mask 45, and/or conductive balls 48c, which are attached to the back surface 45b of the mask 45, from the backside of the mask 45 after separating the mask 45 and the wafer 10. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to an apparatus and method for arranging fine particles having a diameter of about 1 mm or less at a predetermined position, and in particular, conductivity used for mounting a semiconductor device or an optical device such as an integrated circuit device or a display panel. The present invention relates to an apparatus and a method suitable for arranging fine particles.

  When mounting semiconductor devices or optical devices such as LSI (Large Scale Integration) and LCD (Liquid Crystal Display), they are coated with solder or other conductive metal, and further to obtain electrical connection. A package or a substrate in which fine particles are arranged in a desired pattern is used. As a method for arranging fine particles in a desired pattern, the fine particles for transfer are referred to as a squeegee on a mask having an opening for transfer as disclosed in Japanese Patent Laid-Open No. 9-148332. There is known a method of arranging fine particles at a desired position while being moved by a brush-like moving means.

JP-A-9-148332

  In many cases, the workpiece is preliminarily coated with a material to be bonded to the conductive ball, such as a flux, at a position where the conductive ball is disposed. In the case of flux, the conductive ball can be fixed by reflowing after the conductive ball is disposed. If the conductive balls filled in the mask opening pattern are not in close contact with the flux due to some reason, the conductive balls may come off the mask side when removing the mask, or may fall off the flux. is there. Therefore, a method is provided that can manufacture a work in which conductive balls are in close contact with the flux with high yield.

One aspect of the present invention is a method of manufacturing a work including a conductive ball using an apparatus that places the conductive ball on the work via a mask, the mask including the conductive ball as a predetermined part of the work. The apparatus is connected to a filling head for filling the opening pattern of the mask with conductive balls, a mechanism for moving the filling head along the surface of the mask, and a vacuum pump. A cleaning head that cleans the back surface of the mask only by suction, and a mechanism that moves the cleaning head along the back surface of the mask. The method includes aligning the mask and the workpiece, and along the surface. The filling head is moved by a moving mechanism to fill the opening pattern of the mask with the conductive balls, and the back surface is removed after removing the mask and workpiece. Move the cleaning head by a mechanism that moves along the steps of cleaning by suction only the rear surface of the mask, removing the conductive balls arrived on the back surface of the conductive ball or a mask state jammed in the opening pattern of the mask Have
Another aspect of the present invention is an apparatus for placing conductive balls on a workpiece via a mask, the mask having an opening pattern for placing the conductive balls at predetermined positions on the workpiece. The apparatus includes a filling head that fills the opening pattern of the mask aligned with the workpiece with the conductive balls, a mechanism that moves the filling head along the surface of the mask, and a vacuum pump. It has a cleaning head for cleaning the back surface only by suction, and a mechanism for moving the cleaning head along the back surface of the mask after removing the workpiece from the mask.

  Conductive arrangement in which fine particles such as solder balls, gold balls, or copper balls, which are used in the mounting of semiconductor devices or optical devices, are accurately and reliably arranged according to a desired pattern on a workpiece such as a wafer. Work with a ball can be manufactured with good yield.

It is a top view which shows schematic structure of the ball mounter of this invention. It is a side view of the ball mounter shown in FIG. It is a block diagram which shows the outline of the flow of the operation | work performed by the ball mounter shown in FIG. It is a figure which shows a mode that a wafer is pre-aligned. It is a figure which shows a mode that the curvature of a wafer is corrected. It is a figure which shows a mode that the mask for printing and a wafer are aligned when printing a flux. It is a figure which shows a mode that the flux was apply | coated to the mask for printing, when printing a flux. It is a figure which shows a mode that the flux is printed. It is a figure which shows the mode of the mask for printing and a wafer when printing of a flux is complete | finished. It is a top view which shows schematic structure of a ball | bowl filling part. It is sectional drawing which shows schematic structure of the head for filling. FIG. 12A is a diagram showing a state in which solder balls are filled in the opening pattern of the filling mask, and FIG. 12B is a diagram showing a state of the filling mask after the solder balls are filled in the opening pattern. is there. FIG. 13A is a view showing a state where the solder balls remaining on the filling mask are removed, and FIG. 13B is a view showing a state where the solder balls are removed. FIG. 14A is a diagram illustrating a state where the filling mask is removed from the wafer, and FIG. 14B is a diagram illustrating a state where the back surface of the filling mask is being cleaned. It is a figure which shows the filling head of the type which blows off air. It is a figure which shows the removal head of the type which blows off air.

  Hereinafter, the present invention will be further described with reference to the drawings. FIG. 1 is a plan view showing a schematic configuration of a fine particle arrangement device (microball mounter, hereinafter referred to as a ball mounter) according to the present invention. FIG. 2 shows a schematic side view of the ball mounter 1. For example, the ball mounter 1 can mount a fine particle such as a solder ball with high accuracy at a predetermined position of an 8-inch or 12-inch semiconductor wafer 10 as a work. The ball mounter 1 moves the wafer 10 supplied from the wafer stocker 31 and corrects the warp. Then, the ball mounter 1 performs a flux printing process, performs a solder ball filling process, and transfers the filled wafer 10 to another wafer. A series of processing such as storing in the stocker 32 is performed fully automatically.

  The ball mounter 1 is broadly divided into a loader / unloader section 21 for supplying and storing a wafer 10 and a wafer 10 supplied from the loader / unloader section 21 on an XYZθ table 23. And a mount section 22 for performing flux printing and mounting of balls (fine particles) while moving to X. The mount section 22 includes a warp correction unit 25 that corrects the warpage of the wafer 10 supplied from the loader / unloader section 21, a screen printing unit 26 that prints a flux on the warped wafer 10, and a wafer on which the flux is printed. 10 is provided with a ball mounting unit 27 for mounting balls (fine particles), and these are arranged in order in the transport direction X.

  FIG. 3 is a block diagram showing an outline of the work flow executed by the ball mounter 1. Below, along with this work flow (steps S1 to S11), the configuration and operation of each unit will be described. First, the loader / unloader section 21 pre-aligns the wafer 10 supplied from the supply stocker 31, takes out the wafer 10 from the supply wafer stocker 31, and loads the wafer 10 into the storage stocker 32. And a transfer robot 34 that performs storage, transfer / recovery of the wafer 10 to the pre-alignment unit 33, transfer / recovery of the wafer 10 to the table 23 of the mount section 22, and the like. The transfer robot 34 pulls out one wafer 10 from the supply stocker 31. As shown in FIG. 4, the drawn wafer 10 is supplied to a pre-alignment unit (pre-aligner) 33 by a transfer robot 34, and the pre-aligner 33 is ± 0.2 mm in the XY direction and the angle (θ) is ± 0.2 °. The wafer 10 is positioned with a certain degree of accuracy (step S1). The pre-aligned wafer 10 is supplied to the table 23 of the mount section 22 by the transfer robot 34 (step S2).

  Next, as shown in FIG. 5, the warp correction unit 25 corrects the warp of the wafer 10 supplied to the table 23 (step S3). In the warp correction unit 25, the wafer 10 placed on the table 23 is vacuum-sucked from the lower side of the table 23 and held, so that the wafer 10 is placed on the table 23 maintained at a high level. The warpage of the wafer 10 is corrected by bringing it into close contact. In the subsequent steps, the wafer 10 moves together with the table 23 and is maintained in a horizontal flat state in close contact with the table 23.

  Next, as shown in FIGS. 6 to 9, a flux for mounting solder balls, which are fine particles, is printed on the wafer 10 in the screen printing unit 26. First, as shown in FIG. 6, in the printing unit 26, the pattern of the wafer 10 conveyed while being mounted on the table 23 is recognized by the recognition camera 26 a, and the printing mask 37 and the wafer 10 are detected by image processing. Alignment is performed (step S4). The printing mask 37 is recognized by the screen printing unit 26 using the recognition camera 26a at the time of mask replacement, and a mask pattern is arranged at a predetermined position on the wafer 10 during alignment by performing image processing in advance. Has been pre-processed.

  Next, the flux is printed (step S5). As shown in FIG. 7, a flux is applied on the printing mask 37. Further, as shown in FIG. 8, the flux 11 is applied to the wafer 10 by pressing the printing mask 37 against the wafer 10 by the printing squeegee 26 b. The printing mask 37 is aligned with a predetermined gap between the wafer 10 and moves the squeegee 26b in the horizontal direction (X direction or Y direction) so as to push down the mask 37. As a result, only the mask 37 pushed down by the squeegee 26 b comes into contact with the wafer 10, and the flux 11 is applied to the wafer 10 through the opening pattern 37 a of the mask 37. Therefore, as shown in FIG. 9, the flux 11 can be printed at a desired position on the wafer 10 at a position and shape based on the opening pattern 37 a of the mask 37 without bringing the mask 37 into close contact with the wafer 10.

  The screen printing unit 26 includes a mechanism 36 for cleaning the printing mask 37, and performs mask cleaning every time the flux printing is completed on one wafer 10 or when it is determined that mask cleaning is necessary. Perform (step S6). The printing mechanism of the flux 11 can be maintained by removing the flux adhering to the printing mask 37 by the cleaning mechanism 36. The wafer 10 on which flux printing has been completed moves to the ball mounting unit 27 together with the table 23.

  As shown in FIG. 1, the ball mounting unit 27 of this example includes a ball filling unit 28 and a mask cleaning unit 29. In the ball filling unit 28, the filling ball 41 fills the opening pattern 46 of the filling mask 45 with the solder balls 48, which are fine particles (step S8 (first step)), and then the mask 45 is placed on the wafer 10. Before removing the solder ball 48, the solder ball 48 remaining on the mask 45 is removed by the removing head 42 (step S9 (second step)). Further, after the mask 45 is removed from the wafer 10, the solder balls that may remain on the back surface of the mask 45 are removed by the cleaning head 80 in the mask cleaning unit 29 (step S10 (cleaning process)).

  Prior to these steps, first, in the ball mounting unit 27, the filling mask 45 and the wafer 10 are aligned by image processing with the same configuration as the printing unit 26 described above (step S7). As with the printing mask, the filling mask 45 is also recognized by the ball mounting unit 27 using a recognition camera at the time of replacing the mask, and is subjected to image processing in advance, so that the mask itself is aligned with the unit 27. ing.

  FIG. 10 is a plan view showing a schematic configuration of the ball filling unit 28 of the ball mounting unit 27. The ball filling unit 28 includes a filling head 41, a carriage 62 that supports the filling head 41, and a carriage shaft 63 that supports the carriage 62. The carriage 62 can move the filling head 41 in the Y direction by expanding and contracting an arm 62 a that supports the filling head 41. In addition, the carriage 62 can move in the X direction along the carriage shaft 63, and this system can move the filling head 41 to an arbitrary position in the XY direction of the ball filling unit 28. Therefore, the filling head 41 can be moved linearly or in a circle or even in an ellipse on the XY plane.

  Further, the ball filling unit 28 includes a remaining ball removing head 42, a carriage 65 that supports the removing head 42, and a carriage shaft 64 that supports the carriage 65. The removal head 42 in this example is a head having a shape extending in the Y direction that is equal to or longer than the diameter of the filling mask 45, and the removal head 42 is moved in the Y direction by the carriage 65. The removal head 42 can move over the entire surface of the filling mask 45. The removal head 42 may be supported by a system similar to the filling head 41 and moved to an arbitrary position in the XY direction of the ball filling unit 28.

  FIG. 11 shows a schematic configuration of the filling head 41 in a sectional view. The filling head 41 of this example is a rotary type, and the ball filling unit 28 includes a drive unit 57 that rotationally drives the filling head 41, a shaft 59 that supports the center of the filling head 41, and transmits a rotational force. It has. The filling head 41 includes a disk-shaped squeegee support 51 that rotates about a shaft 59, and a plurality of filling squeegees arranged on the back surface of the squeegee support 51, that is, on the side facing the filling mask 45 and the wafer 10. 52. When viewed from above, the filling squeegee 52 is disposed around the inner circle coaxial with the rotary shaft 59 so as to extend in the tangential direction of the inner circle at a uniform pitch in the circumferential direction. For this reason, by rotating the squeegee support 51, the solder balls 48 are collected in the inner circle by the squeegee 52, and a sufficient amount of the solder balls 48 to efficiently fill the opening pattern of the mask 45 within the range of the inner circle. Can be maintained. Therefore, by moving the surface 45a of the mask 45 while the filling head 41 is rotated, the assembly 49 of a large number of solder balls 48 together with the filling head 41 can be moved along the mask 45, and the opening of the mask 45 The pattern can be filled with the solder balls 48 efficiently and without filling errors (step S8). Therefore, the filling head 41 corresponds to the first particle moving head in the present invention, and this step S8 corresponds to the first step.

  FIGS. 12A and 12B show how the solder balls 48 are filled by the filling head 41 in step S8. In step S8, the filling head 41 fills the opening pattern 46 of the mask 45 while moving the solder balls 48, which are fine particles, and places the solder ball 48 at a predetermined position on the wafer 10. The squeegee 52 disposed on the lower surface of the squeegee support 51 of the filling head 41 includes a plurality of sweep members 52a. These sweep members 52a are formed of a member having an appropriate strength, for example, a conductive and resin brush-like member or a wire, in order to collectively move a large number of sets 49 of solder balls 48. The plurality of sweep members 52a are attached to the support 51 so that the tips of the squeegee 52 move backward with respect to the moving direction. As shown in FIG. 12A, in a state where such a squeegee 52 is in contact with the surface 45a of the filling mask 45, the filling head 41 is rotated and moved along the surface 45a of the mask 45. As a result, the sweep member 52a moves while pushing or sweeping the set 49 of the solder balls 48 on the mask 45. A part of the solder balls 48 of the assembly 49 is filled in the opening pattern 46 and disposed at a predetermined position on the wafer 10. The remaining excessive solder balls 48 are collected by the squeegee 52 to form a set 49, move in the state 45 a on the surface 45 a of the mask 45, and are successively filled in the opening pattern 46.

  Therefore, in step S8 (first step) in which the opening pattern 46 is filled with the solder head 48 by the filling head 41, a sufficient amount of the solder balls 48 are moved as a set 49 with respect to the density of the opening pattern 46. There is a need. For this reason, it is necessary to continue to push a large amount of solder balls 48 in the horizontal direction along the surface 45a of the mask 45 by the sweep member 52a having a certain mechanical strength. Therefore, the sweep member 52a is not deformed along the opening pattern 46 to push the solder ball, and the solder ball 48 from the set 49 is filled into the opening pattern 46 by gravity. In addition, the solder ball 48 is not pushed into the opening pattern 46 with a strong force, but falls due to gravity, so that the solder ball 48 is not damaged or displaced from the position of the opening pattern 46. The solder balls 48 can be arranged at predetermined positions.

  In this step S8, as shown in FIG. 12B, the filling head 41 moves a large amount of solder balls 48 having a sufficient margin with respect to the filling amount for the opening pattern 46, as shown in FIG. After the head 41 is moved, it leaks from the squeegee 52 or overflows, so that a small amount of solder balls 48a are left on the mask 45 in a scattered, dispersed or scattered state. If the amount of solder balls 48 forming the assembly 49 is reduced so as not to leak from the squeegee 52, there is a possibility that the solder balls 48 cannot be moved at a sufficient density with respect to the opening pattern 46. This is for the purpose of preventing such a situation. Further, if the solder ball 48, which is a fine particle, is moved without leakage by the squeegee 52 having high rigidity, it is necessary to press the squeegee 52 with an excessive pressure so that no gap is generated between the squeegee 52 and the mask 45. There is a possibility that the mask 45 may be damaged or the solder ball 48 may be damaged, and such a problem is prevented.

  FIGS. 13A and 13B show how the balls 48a remaining on the mask 45 are removed in step S9. In step S9, the removal head 42 of the ball filling portion 28 is moved to move the solder balls 48a remaining on the mask 45. Therefore, this step S9 corresponds to the second step, and the removal head 42 corresponds to the second particle moving head. The remaining ball removing head 42 in this example includes a squeegee support 53 extending in the X direction and a squeegee 54 disposed on the lower surface of the squeegee support 53. This removal head 42 is intended to move a very small amount of solder balls 48 relative to the filling head 41. Therefore, the mechanical strength of the squeegee 54 is not so required, and conversely, it is desirable that the squeegee 54 has flexibility so as not to form a gap between the squeegee 54 and the mask 45. For this reason, the squeegee 54 of the removal head 42 employs a thin fiber-shaped sweep member 54a made of stainless steel, and a number of sweep members 54a are arranged in a brush shape downward. .

  The removal head 42 is moved in a direction perpendicular to the surface 45a of the mask 45 by moving the sweeping member 54a with an interval such that the fibrous sweep member 54a is always in contact with the surface 45a of the mask 45 and deformed to some extent. It can move in the state where the power of is applied. Accordingly, the sweep member 54a moves so as to sweep the surface 45a of the mask 45 with a scissors, and the solder balls 48a remaining on the surface 45a of the mask 45 can be scraped and moved. Accordingly, as shown in FIG. 13B, the remaining ball or removal head 42 having the soft squeegee 54 is moved on the mask 45 after the ball 48 is filled, so that it remains on the mask surface 45a. The solder balls 48a that are present can be removed by removing them from the mask 45.

  Further, the sweep member 54 a of the removal head 42 is flexible and easily deformed, and is further thin. Therefore, when the surface 45 a of the mask 45 is moved, the sweep member 54 a enters the inside of the opening pattern 46 and is filled with the solder ball 48 filled in the opening pattern 46. Is pressed against the wafer 10 from above. Therefore, the solder balls 48 arranged in the opening pattern 46 are pressed against the flux 11 printed on the wafer 10 to be in close contact with the flux 11, and when the mask 45 is removed, the solder balls 48 are removed together with the mask 45. Or a problem that the solder ball 48 is displaced from the flux 11 can be prevented. Therefore, it is possible to improve the yield of the ball mounted wafer 10 in which the solder balls 48 are arranged at predetermined positions, which are generated in the ball mounter 1 of this example. For this reason, the wafer 10 produced by the ball mounter 1 of this example is placed in a reflow furnace and the solder balls 48 are connected to the wafer 10 via the flux 11, thereby allowing a highly reliable product such as an LSI or LCD. Can be manufactured.

  FIGS. 14A and 14B show how the filling mask 45 is cleaned in step S10. The ball mounting unit 27 includes a mask moving mechanism 58 that removes the filling mask 45 from the wafer 10 and moves it to the cleaning unit 29. Therefore, in step S10 for cleaning the mask, the mask 45 is removed from the wafer 10 to the cleaning unit 29, and then the mask 45 is cleaned. Therefore, the mask moving mechanism 58 corresponds to a means for attaching / detaching the mask to / from the workpiece. The cleaning unit 29 includes a cleaning head 80 for cleaning the mask 45 from the back surface 45b side, a mechanism 81 for moving the cleaning head 80 along the mask back surface 45b, and the mask back surface 45b via the cleaning head 80. And a suction pump (vacuum pump) 82 capable of sucking the solder balls 48.

  In the removing step S9, the remaining balls on the front surface 45a of the mask 45 can be removed by the removing head 42. However, the remaining balls 48c are attached to the back surface 45b of the mask 45 removed from the wafer 10 and are drooped, or the opening pattern 46 is dropped. There is a possibility that the remaining ball 48d is clogged. The ball 48c remaining on the back surface 45b of the mask 45 may cause a positional shift or a gap between the wafer 10 and the mask 45 when the mask 45 is overlapped on the next wafer 10 as it is. It leads to mistakes. Further, if the remaining ball 48d is clogged in the opening pattern 46, there is a possibility that the solder ball is not filled as it is. By cleaning the remaining balls from the back surface 45b of the mask while sucking them with the cleaning head 80, the remaining balls on the back surface 45b of the mask and the opening pattern 46 can be removed, thereby preventing a filling error from occurring.

  In this manner, the processing in the ball mounting unit 27 is completed, and the wafer 10 on which the solder balls 48 are arranged at predetermined positions is conveyed toward the loader / unloader section 21 together with the table 23. Then, it is collected by the transfer robot 34 and stored in the storage stocker 32 (step S11). Thereby, the ball mounting with respect to one wafer 10 is completed.

  In the ball mounter 1 described above, the filling head and the removal head are of a type that moves in contact with the solder ball by the sweep member, but the filling head and / or the removal head is blown out of a gas such as air. It is also possible to use a type that moves fine particles such as solder balls. FIG. 15 shows an outline of a filling head 71 of the type that blows air A in a horizontal direction along the surface 45a of the filling mask 45 and blows away a set 49 of the solder balls 48 in a lump. The filling head 71 has an air nozzle 75 oriented in the horizontal direction, and can blow out the compressed air supplied through the inside of the head 71 along the surface 45a of the mask 45. The ball 48 can be moved.

  FIG. 16 shows a removal head 72 of the type that blows air A from the upper side of the filling mask 45 to blow off the solder balls 48. The removal head 72 has an air nozzle 76 directed obliquely downward, and compressed air supplied via the interior of the removal head 72 can be blown against the mask 45 from obliquely above. It is also possible to function as the removal head 72 by changing the direction of the nozzle 76 of the filling head 71. By supplying the air A from above the mask 45, the remaining balls 48 a scattered on the surface 45 a of the mask 45 can be lifted and reliably moved and removed from the surface 45 a of the mask 45. When filling, air cannot be supplied in a direction that causes the solder balls 48 to float, but it is preferable to remove them. Furthermore, by blowing air A from above on the mask 45, the solder balls 48 filled in the opening pattern 46 of the mask 45 can be pressed against the wafer 10. Therefore, similarly to the above-described mechanical removal head 42, the solder balls 48 filled in the opening pattern 46 can be brought into close contact with the flux 11, and the yield of the wafer 10 on which the solder balls are mounted can be improved. The gas blown out to move the solder ball is not limited to the air A, but may be nitrogen gas, argon gas or ionized gas.

  Although the present invention has been described by taking a ball mounter in which the solder balls 48 are mounted on the wafer 10 as an example, the present invention can be applied to any apparatus in which a mask is set on a work and fine particles are transferred to an opening pattern of the mask. Further, the shape of the head or the mechanism for moving the head is merely an example, and is not limited to the above example. For example, the filling head may reciprocate linearly instead of rotating, or the mask and workpiece may be moved together instead of moving the head.

  As described above, in order to fill or arrange the fine particles without mistake in the plurality of fine openings (openings) provided in the mask, the amount of fine particles filled in the openings, that is, the number of openings per area. It is necessary to move an amount of fine particles having a sufficient margin with respect to the density with a squeegee on the mask. However, when a large amount of fine particles are moved on the mask by the squeegee, the fine particles leak from the squeegee and the fine particles remain on the mask. When the fine particles remaining on the mask are removed from the work, the fine particles enter the opening of the mask at an unintended timing and become defective particles on the work. It may become an obstacle when setting. On the other hand, if the amount of fine particles is reduced so that the fine particles do not remain in the mask after the squeegee moves (sweep) so as to sweep the fine particles on the mask, the fine particles can be surely arranged in all openings. It may become difficult and filling mistakes may occur.

  In addition, a squeegee that moves a sufficient amount of microparticles at a time to improve packing efficiency must have a material or structure with sufficient strength so that a large amount of microparticles can be mechanically pressed. There is. Therefore, a squeegee with a highly flexible material or structure suitable for sweeping a small amount of fine particles is not suitable.

  Therefore, a method and apparatus are provided that can reliably fill the opening of the mask with the fine particles and arrange the fine particles so that the fine particles do not remain in the mask, thereby improving the yield.

  A method of arranging fine particles on a work using a mask having an opening pattern for arranging fine particles at a predetermined position of the work is a first particle suitable for moving a large amount of fine particles. A first step of moving the microparticles along the mask by the moving means, and a second step of moving the microparticles along the mask by the second particle moving means suitable for moving a small amount of microparticles. Process. In the first step, the first particle moving means moves a set of microparticles in an amount sufficient to fill the opening pattern along the mask, and in the second step, the second step The particle moving means moves the dissipated fine particles along the mask.

  In this fine particle arrangement method, the first step for filling the fine particles into the opening pattern and the second step for moving the fine particles out of the mask are separated. To do. Therefore, in the first step, a sufficient amount for filling the opening pattern with the microparticles, that is, the first moving means suitable for moving a large amount of the microparticles can be used, and the filling efficiency is improved. In addition, the occurrence of filling mistakes can be prevented. The first moving means may be not suitable for collecting the remaining fine particles.

  On the other hand, in the second step, it is not necessary to move a large amount of microparticles, and the second moving means suitable for moving a small amount of microparticles scattered on the mask remains on the mask. It is possible to remove the fine particles and prevent troubles caused by them. Furthermore, since the second moving means does not need to move a large amount of microparticles and it is necessary to move the microparticles remaining on the mask with certainty, the direction of the force applied to the microparticles for movement can be determined. It is preferable to use moving means that can change the direction of the force. For this reason, the second particle moving means is added with a function of pressing the fine particles filled in the opening pattern of the mask against the work from above and enhancing the adhesion between the filled fine particles arranged and the work. It is possible to improve the yield of workpieces in which fine particles are arranged at predetermined positions.

  In many cases, the workpiece is preliminarily coated with a material that binds to the fine particles such as a flux at a position where the fine particles are arranged. In the case of flux, the fine particles can be fixed by reflowing after the fine particles are arranged. If the fine particles filled in the opening pattern of the mask are not in close contact with the flux for some reason, when removing the mask, the fine particles may come off at the mask side or may fall off the flux. If a force can be applied to the fine particles from above the opening pattern of the mask by the second particle moving means, the fine particles can be reliably adhered to the flux, so that the problem that the fine particles are detached or displaced can be solved.

  The first particle moving means that needs to move a large amount of microparticles mainly needs to apply a horizontal force along the surface of the mask to the microparticles, and pushing the microparticles in the opening pattern difficult. On the other hand, the second particle moving means applies a force having a higher ratio in the direction perpendicular to the surface of the mask to the fine particles than the first particle moving means, so that the fine particles remaining on the mask surface. Can be reliably moved, and fine particles in the opening pattern of the mask can be pushed and brought into close contact with the workpiece.

  For example, when the first particle moving means and the second particle moving means include a sweep member that mechanically contacts the microparticle and moves the microparticle, the sweep member of the second particle moving means is It is desirable to be more flexible than the sweep member of the first particle moving means so that the fine particles remaining on the surface of the mask can be reliably captured and moved. Then, the flexible sweep member can be deformed and brought into contact with the fine particles in the opening pattern of the mask, thereby pressing the fine particles in the opening pattern against the workpiece. In particular, as the sweep member, a wire-like member having a diameter equal to or smaller than the diameter of the fine particles can be used, and when the member moves so as to sweep the surface of the mask, the member enters the upper portion of the opening pattern and the opening pattern. The fine particles inside can be pressed against the workpiece.

  When the first particle moving means and the second particle moving means are those that blow out gas to move microparticles, by changing the gas blowing angle in the first step and the second step, In the first step, it is desirable to blow out gas in the horizontal direction and push the fine particles, and in the second step, blow out gas from diagonally upward and push the fine particles. And in a 2nd process, the microparticle with which the opening pattern was filled can be pressed against a workpiece | work by blowing off gas from diagonally upward. In the first step, the particle moving means provided with the sweep member is used, and in the second step, the particle moving means for blowing out the gas is used, or conversely, the particle moving means for blowing out the gas in the first step is used. It is possible to use particle moving means provided with a sweep member in this step.

  Furthermore, the present invention provides an apparatus for arranging microparticles on a workpiece using a mask having an opening pattern for arranging microparticles at predetermined positions on the workpiece. The fine particle disposing apparatus is dissipated along the mask with first particle moving means for collectively moving a set of fine particles sufficient to fill the opening pattern along the mask. Second particle moving means for moving the microparticles. Furthermore, for the reasons described above, the first particle moving means mainly applies a horizontal force along the surface of the mask to the fine particles, and the second particle moving means is more effective than the first particle moving means. It is desirable that a force with a high ratio in the direction perpendicular to the surface of the mask is applied to the fine particles.

  When the first particle moving means and the second particle moving means include a moving member that moves the microparticles in mechanical contact with the microparticles, the moving member of the second particle moving means is the first It is desirable to be more flexible than the moving member of the particle moving means. Further, when the first particle moving means and the second particle moving means blow out the gas to move the microparticles, the second particle moving means causes the gas to flow at an angle different from that of the first particle moving means. It is desirable to blow out.

  In order to further improve the yield of the work on which the fine particles are arranged, in this fine particle arranging method, it is desirable to provide a step of retracting the mask from the work and cleaning at least the back surface of the retracted mask. In addition, it is desirable that the apparatus for arranging fine particles further includes means for attaching / detaching the mask to / from the work and means for cleaning at least the back surface of the mask away from the work. Even if the fine particles remaining on the surface of the mask are removed by the second particle moving means, when the mask is removed from the workpiece, the fine particles are adhered to the back surface of the mask, or the fine particles are not present in the opening pattern of the mask. It may be clogged. Those fine particles become an obstacle when the mask is attached to the next workpiece and the fine particles are arranged. In particular, the fine particles adhering to the back surface of the mask may cause damage to the workpiece when the mask is set on the next workpiece, or generate an unintended gap between the workpiece and the mask. It becomes a factor that it becomes impossible to place in the place. Therefore, after removing the mask from the work, it is useful to improve the yield by cleaning at least the back surface to remove the fine particles remaining on the back surface of the mask.

  In the cleaning step, a method of sucking the back surface of the mask is desirable. Moreover, it is desirable that the cleaning means includes a means for sucking the back surface of the mask. By sucking the mask from the back surface, it is possible to reliably remove the fine particles clogged in the opening pattern, and the yield can be improved.

  With this fine particle arrangement method and arrangement apparatus, it is possible to prevent problems caused by the fine particles remaining in the mask and to reliably fill the fine pattern in the opening pattern of the mask. For this reason, fine particles such as solder balls, gold balls, or copper balls used in the mounting of semiconductor devices or optical devices are accurately arranged according to a desired pattern on a workpiece such as a wafer with high reliability. Therefore, a work having fine particles can be manufactured with a high yield.

  That is, the method of arranging the fine particles on the workpiece using a mask having an opening pattern for arranging the fine particles at a predetermined position of the workpiece is suitable for moving a large amount of the fine particles. A first step of moving the fine particles along the mask by the first particle moving means, and a second particle moving means suitable for moving a small amount of the fine particles along the mask. And a second step of moving the fine particles. A method of arranging the microparticles on the workpiece using a mask having an opening pattern for arranging the microparticles at a predetermined position of the workpiece is performed along the mask by a first particle moving unit. The first step of collectively moving a collection of the microparticles in an amount sufficient to fill the opening pattern, and the microparticles dissipated along the mask by the second particle moving means And a second step of moving. The first step is intended to fill the opening pattern with the fine particles, and the second step is intended to move the fine particles out of the mask. The first particle moving means mainly applies a horizontal force along the surface of the mask to the fine particles, and the second particle moving means is more effective than the first particle moving means. A force having a high ratio in the direction perpendicular to the surface of the mask is applied to the fine particles. The first particle moving means and the second particle moving means include a sweep member that moves the fine particles in mechanical contact with the fine particles, and the sweep member of the second particle moving means includes: It is more flexible than the sweep member of the first particle moving means. The first particle moving means and the second particle moving means move the fine particles by blowing gas, and the gas blowing angles in the first step and the second step are different. The arrangement method further includes a step of retracting the mask from the workpiece and cleaning at least the back surface of the retracted mask. In the cleaning step, the back surface of the mask is cleaned by suction.

  An apparatus for arranging the microparticles on the workpiece using a mask having an opening pattern for arranging the microparticles at a predetermined position of the workpiece is used to fill the aperture pattern along the mask. A first particle moving unit that collectively moves a set of the microparticles in a sufficient amount; and a second particle moving unit that moves the dissipated microparticles along the mask. The first particle moving means mainly applies a horizontal force along the surface of the mask to the fine particles, and the second particle moving means is more effective than the first particle moving means. A force having a high ratio in the direction perpendicular to the surface of the mask is applied to the fine particles. The first particle moving means and the second particle moving means include a moving member that mechanically contacts the fine particles and moves the fine particles, and the moving members of the second particle moving means include: It is more flexible than the moving member of the first particle moving means. The first particle moving means and the second particle moving means blow out a gas to move the fine particles, and the second particle moving means discharges the gas at an angle different from that of the first particle moving means. Blow out. The apparatus further includes means for attaching / detaching the mask to / from the workpiece, and means for cleaning at least the back surface of the mask away from the workpiece. The cleaning means includes means for sucking the back surface of the mask.

1 Ball mounter 10 Wafer (work)
41, 71 Filling head (first particle moving means)
42, 72 Removal head (second particle moving means)
45 Filling mask 46 Opening pattern 48 Solder ball 49 Solder ball assembly 80 Cleaning head

Claims (2)

A method of manufacturing a workpiece provided with the conductive ball using a device that places the conductive ball on a workpiece via a mask,
The mask includes an opening pattern for disposing the conductive ball at a predetermined position of the work,
The device is
A filling head for filling the conductive ball in the opening pattern of the mask;
A mechanism for moving the filling head along the surface of the mask;
A cleaning head connected to a vacuum pump and cleaning the back surface of the mask only by suction ;
A mechanism for moving the cleaning head along the back surface of the mask,
The method is
Aligning the mask and the workpiece;
Moving the filling head by a mechanism that moves along the surface, and filling the conductive balls into the opening pattern of the mask;
After removing the mask and the workpiece, the cleaning head is moved by a mechanism that moves along the back surface , the back surface of the mask is cleaned only by suction, and the opening pattern of the mask is clogged. Removing the conductive ball or the conductive ball attached to the back surface of the mask. An apparatus for placing conductive balls on a workpiece via a mask,
The mask includes an opening pattern for disposing the conductive ball at a predetermined position of the work,
The device is
A filling head for filling the conductive balls in the opening pattern of the mask aligned with the workpiece;
A mechanism for moving the filling head along the surface of the mask;
A cleaning head connected to a vacuum pump and cleaning the back surface of the mask only by suction ;
And a mechanism for moving the cleaning head along the back surface of the mask after removing the workpiece from the mask.

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