JP6389988B2 - Foreign matter removal device - Google Patents

Description

  The present invention relates to a foreign matter removing device, and more particularly to a structure of a foreign matter removing device that removes foreign matter using solid carbon dioxide particles.

  In the manufacturing process of electronic parts such as ICs, a die bonding apparatus for bonding a semiconductor die cut from a wafer to a substrate, a wire bonding apparatus for connecting a semiconductor die electrode bonded to the substrate and a substrate electrode with a wire, and a semiconductor die Many devices such as a flip chip bonding apparatus are used in which bumps are formed on the electrodes and the semiconductor die is inverted and fixed to the substrate, and the electrodes of the semiconductor die and the substrate are connected. Recently, a bonding apparatus for laminating and bonding a semiconductor die on a semiconductor die of a wafer has also been used.

  In such a bonding apparatus, a semiconductor die is bonded to a predetermined position of the substrate, or an electrode of the semiconductor die and an electrode of the substrate are connected by a wire.

  In such an apparatus, if foreign matter such as dust adheres to the surface of a substrate or the like, the adhesive strength of the adhesive may be reduced. In addition, if dust or the like adheres to the surface of the substrate electrode or the semiconductor die electrode, the bonding quality between the electrode and the wire may deteriorate.

  For this reason, an apparatus has been proposed in which air is blown to the substrate to blow off the foreign matter adhering to the substrate, and the blown-off foreign matter is sucked and collected to remove the foreign matter (for example, see Patent Document 1).

In addition, a technique for removing foreign matter from a semiconductor die or a substrate using liquid carbon dioxide (CO ₂ ) is also used (see, for example, Patent Document 2). In this method, liquid carbon dioxide is sprayed from a spray nozzle onto a substrate, and dry ice particles that have been frozen by adiabatic expansion during spraying to become dry ice collide with the substrate, so that foreign matter on the surface of a semiconductor die or substrate can be removed. The removal is performed.

JP 2012-199458 A JP 2000-117201 A

  However, in the foreign matter removal method described in Patent Document 2, if the dry ice particles are ejected vigorously in order to remove finer foreign matters, the particle diameter of the dry ice particles increases, and the fine foreign matters are effectively removed. There was a problem that it could not be removed. Further, when the particle size of the dry ice is increased, there is a problem that the substrate and the semiconductor die are damaged due to the collision of the dry ice particles.

  Therefore, an object of the present invention is to remove minute foreign matters while suppressing damage to a substrate and a semiconductor die.

The foreign matter removing apparatus of the present invention expands a pressurized flow of liquid carbon dioxide, and forms a solid carbon dioxide particle in the flow by cooling at the time of expansion, and is connected to the nozzle. A chamber into which the carbon dioxide particles flow in, a spout connected to the chamber and ejecting solid carbon dioxide particles toward the surface of the flat plate member, and a suction port disposed adjacent to the spout A foreign matter removing apparatus, wherein a distance from a nozzle outlet to a chamber is changed to change a flight distance of solid carbon dioxide particles from the nozzle outlet to the chamber, whereby a solid dioxide dioxide jetted from the jet outlet is changed. It is characterized by adjusting the particle diameter of carbon particles to submicron order.

  The foreign matter removing apparatus of the present invention is suitable for adjusting the particle diameter of individual carbon dioxide particles ejected from the ejection port by changing the heating amount of the heater, including a heater attached to the outer surface of the chamber.

  In the foreign matter removing apparatus according to the aspect of the invention, it is preferable that the ejection port is a slit that communicates with the chamber and ejects the carbon dioxide particles in a strip shape toward the surface of the flat plate member.

  In the foreign matter removing apparatus according to the present invention, it is preferable that the ejection port is a plurality of holes arranged in a straight line in communication with the chamber.

  In the foreign matter removing apparatus of the present invention, the jet outlet is also suitable for injecting the carbon dioxide particles while inclining the carbon dioxide particles in the direction of the suction port.

  The foreign matter removing apparatus of the present invention may further include an air inlet for allowing compressed air to flow into the chamber, and the chamber may be suitable for mixing the carbon dioxide particles and the compressed air.

  The present invention can remove minute foreign matters while suppressing damage to a substrate and a semiconductor die.

It is a perspective view which shows the foreign material removal apparatus in embodiment of this invention. It is sectional drawing of the cleaning head of the foreign material removal apparatus shown in FIG. FIG. 2 is an explanatory perspective view showing a structure of a main body and a lid of the cleaning head of the foreign substance removing device shown in FIG. It is the figure which looked at the lower surface in which the suction opening and slit of the cleaning head shown in FIG. 1 are arrange | positioned from upper direction, and is explanatory drawing which shows operation | movement of the foreign material removal apparatus of embodiment of this invention. It is a graph which shows the change of the particle diameter with respect to the flight distance of a dry ice particle. It is a graph which shows the change of the particle diameter of the dry ice particle with respect to atmospheric temperature. It is sectional drawing of the cleaning head of the foreign material removal apparatus of other embodiment of this invention. FIG. 7 is a diagram of a lower surface where a suction port and an ejection port of a cleaning head of a foreign matter removing apparatus according to another embodiment of the present invention are arranged as viewed from above, and shows the operation of the foreign matter removing apparatus according to another embodiment of the present invention. It is explanatory drawing shown.

  Hereinafter, the foreign matter removing apparatus 100 of the present embodiment will be described with reference to the drawings. As shown in FIG. 1, the foreign matter removing apparatus 100 according to the present embodiment includes a cleaning head 20 and a drive unit 40 that moves the cleaning head 20 in a direction orthogonal to the transport direction. In FIG. 1, the transport direction of the substrate 13 which is a flat plate member guided by the guide rails 11 and 12 and transported in the horizontal direction is the X direction, and the direction perpendicular to the X direction on the same plane as the X direction is the Y direction. The direction perpendicular to the XY plane will be described as the Z direction. A stage 45 that vacuum-sucks and heats the substrate 13 is disposed below the substrate 13.

  As shown in FIG. 1, the cleaning head 20 has a rectangular parallelepiped shape in which a lid 22 is attached to a rear surface 21 b of a main body 21, and solid carbon dioxide particles (hereinafter referred to as dry ice particles) for removing foreign substances are supplied to the upper part. An inlet connection pipe 25 and a suction connection pipe 26 connected to a vacuum device (not shown) are attached.

  As shown in FIG. 1, one side surface of the cleaning head 20 is connected to the arm 28 via a connection member 27. The arm 28 reciprocates in the Y direction by the drive unit 40. The cleaning head 20 is attached to the arm 28 so as to be slightly inclined with respect to the surface of the substrate 13. There is a gap between the surface of the substrate 13 and the lower surface of the cleaning head 20, and the cleaning head 20 moves on the upper side of the substrate 13 in the Y direction along the surface of the substrate 13.

  Next, the structure of the cleaning head 20 of the foreign matter removing apparatus 100 according to the present embodiment will be described with reference to FIGS. 2, 3A, and 3B. As shown in FIGS. 2, 3 (a), and 3 (b), the cleaning head 20 includes a main body 21 and a lid 22 that is fixed to the rear surface 21 b of the main body 21.

  As shown in FIG. 3A, a rectangular suction port 24 is dug in the lower surface of the main body 21. Further, the rear surface 21b of the main body 21 is formed with a recess 29a constituting a chamber 29 described later. The lower side of the recess 29 a is an inclined surface 29 b that is inclined toward the suction port 24.

  As shown in FIG. 3 (b), the lid 22 includes a flange 22 a that is in close contact with a flat surface other than the recess 29 a of the rear surface 21 b of the main body 21, and a wedge-shaped inclined portion 22 b that is parallel to the inclined surface 29 b of the main body 21. ing. When the inclined portion 22b of the lid 22 is aligned with the inclined surface 29b of the main body and the flange 22a is screwed to the rear surface 21b as shown in FIG. 3B, the concave portion 29a of the main body 21 and the lid 22 are shown in FIG. A chamber 29 extending linearly in the X direction is formed between the first flange 22a and the second flange 22a. A slit which is an injection port that injects a mixed fluid of gaseous carbon dioxide and dry ice particles in a band shape toward the surface of the substrate 13 between the inclined surface 29 b of the main body 21 and the inclined portion 22 b of the lid 22. 23 is formed. As shown in FIG. 2, the slit 23 is inclined toward the suction port 24. As shown in FIG. 4, the length of the suction port 24 in the X direction is longer than the length of the slit 23 in the X direction, and extends to the vicinity of both side surfaces of the cleaning head 20 from the slit 23. FIG. 4 is a view of the lower surface of the cleaning head 20 where the suction port 24 and the slit 23 are disposed as viewed from above.

  As shown in FIG. 2, a sleeve 30 is connected to the inlet connection pipe 25, and a nozzle 31 is connected to the sleeve 30. The sleeve 30 is provided with threaded portions 30a and 30b on the inlet side and the outlet side, respectively, the threaded portion 30a on the inlet side meshes with the threaded portion 31b on the outlet side of the nozzle, and the threaded portion 30b on the outlet side It meshes with the threaded portion 25 a on the inlet side of the inlet connecting pipe 25. The sleeve 30 adjusts the engagement length between the screw portion 30a on the inlet side and the screw portion 31b on the outlet side of the nozzle, and the engagement length between the screw portion 30b on the outlet side and the screw portion 25a on the inlet side of the inlet connection pipe 25. By doing so, the distance from the outlet of the nozzle 31 to the chamber 29 can be changed. The nozzle 31 is connected to a liquid carbon dioxide supply device that supplies pressurized liquid carbon dioxide. Further, as shown in FIG. 2, a heater 35 is attached to the back surface of the lid 22.

  The operation of the foreign matter removing apparatus 100 configured as described above will be described with reference to FIGS. 2 and 4 to 6. When the substrate 13 is transported onto the stage 45 by a transport device (not shown), the stage 45 vacuum-sucks and fixes the substrate 13 and turns on the built-in heater to turn the substrate 13 on, for example, 80 Heat to about ℃.

  Next, pressurized liquid carbon dioxide supplied to the nozzle 31 from a liquid carbon dioxide supply device (not shown) is introduced. The liquid carbon dioxide flowing into the nozzle 31 is compressed up to the throttle portion 31c of the nozzle 31, and when it passes through the throttle portion 31c, it adiabatically expands and the temperature decreases. Due to this temperature decrease, the liquid carbon dioxide changes to solid carbon dioxide particles (dry ice particles). Moreover, a part changes to gaseous carbon dioxide. The mixed fluid of gaseous carbon dioxide and dry ice particles flows from the nozzle 31 through the sleeve 30 and the inlet connection pipe 25 into the chamber 29 of the cleaning head 20 as indicated by an arrow 91 in FIG. . The mixed fluid of gaseous carbon dioxide and dry ice particles flowing into the chamber 29 is jetted obliquely downward toward the surface of the substrate 13 through the slit 23. Since the substrate 13 is heated to about 80 ° C. by the stage 45, when the dry ice particles collide with the minute foreign matter 50 on the surface of the substrate 13, the dry ice particles instantaneously sublimate and expand into gaseous carbon dioxide. Become. The minute foreign matter 50 adhering to the surface of the substrate 13 is removed from the surface of the substrate 13 by the fluid force during the sublimation and expansion. Since the mixed fluid of gaseous carbon dioxide and dry ice particles is ejected from the slit 23 in the direction of the suction port 24 as indicated by an arrow 95 in FIG. 4, the minute foreign matter 50 removed from the surface of the substrate 13 is As shown by an arrow 92 in FIG. 2, the air is sucked into a suction port 24 provided adjacent to the slit 23 and sucked from a suction connection pipe 26 to a vacuum device (not shown). Here, the minute foreign matter 50 is, for example, one having a size of less than 50 μm.

  Similarly to the dry ice particles, gaseous carbon dioxide ejected from the slits 23 together with the dry ice particles is ejected obliquely downward from the slits 23 toward the surface of the substrate 13 and is attached to the surface of the substrate 13. The foreign matter 51 larger than 50 is blown off and removed. The foreign matter 51 blown off by gaseous carbon dioxide is also sucked into a suction port 24 provided adjacent to the slit 23 and sucked into a vacuum device (not shown) from the suction connection pipe 26.

  As shown in FIG. 4, when the cleaning head 20 is reciprocated in the Y direction while ejecting a mixed fluid of gaseous carbon dioxide and dry ice particles from the slit 23 as indicated by an arrow 95 in FIG. The fine foreign matter 50 and the foreign matter 51 in the region B of the substrate 13 shown in FIG. 4 is a region where the removal of the minute foreign matter 50 and the foreign matter 51 on the surface of the substrate 13 is completed, and the region C on the upstream side in the transport direction of the region B is: This is a region where the fine foreign matter 50 and foreign matter 51 on the surface of the substrate 13 are not removed.

  In the foreign matter removing apparatus 100 according to the present embodiment, as shown in FIG. 4, the length of the suction port 24 in the Y direction is longer than the length of the slit 23 in the Y direction, and on both side surfaces of the cleaning head 20 than the slit 23. It extends to the vicinity. For this reason, the fine foreign matter 50 and the foreign matter 51 removed from the surface of the substrate 13 by the mixed fluid of gaseous carbon dioxide and dry ice particles ejected from the slit 23 are blown away in a direction inclined from the Y direction to the X direction. Even in this case, the blown-out minute foreign matter 50 and foreign matter 51 can be sucked by the suction port 24. For this reason, it can suppress that the fine foreign material 50 and the foreign material 51 adhere again to the surface of the board | substrate 13 of the area | region A which foreign material removal was complete | finished, and the cleanliness of the board | substrate 13 can be improved.

  Here, if the particle diameter of the dry ice particles sprayed on the substrate 13 is too large, the fine foreign matter 50 cannot be effectively removed, and the substrate 13 is damaged by the collision of the dry ice particles. According to the test, it is known that when the particle diameter of the dry ice particles is set to the submicron order, the minute foreign matter 50 can be removed without damaging the substrate 13 or the semiconductor die attached to the substrate 13.

  On the other hand, the particle diameter of the dry ice particles ejected from the nozzle 31 becomes smaller as the flight distance L from the outlet of the nozzle 31 becomes longer as shown in FIG. Further, as shown in FIG. 6, the particle diameter of the dry ice particles ejected from the nozzle 31 decreases as the atmospheric temperature T during flight increases. Accordingly, the foreign matter removing apparatus 100 according to the present embodiment is configured so that the engagement length between the screw portion 30a on the inlet side of the sleeve 30 and the screw portion 31b on the outlet side of the nozzle, and the inlet side of the screw portion 30b on the outlet side and the inlet connection pipe 25 is set. By adjusting the meshing length with the thread portion 25a, the particle size of the dry ice particles ejected from the slit 23 can be adjusted by changing the flight distance L from the outlet of the nozzle 31 to the chamber 29. Further, the foreign matter removing apparatus 100 of the present embodiment adjusts the particle size of the dry ice particles ejected from the slit 23 by changing the temperature of the chamber 29 by the heater 35 attached to the back surface of the lid 22 constituting the chamber 29. be able to.

  The meshing lengths of the threaded portions 30a and 30b of the sleeve 30 and the heating heat amount of the heater 35 may be adjusted by a test or the like so that the particle size of the dry ice particles ejected from the slit 23 is on the order of submicrons. Further, the particle size of the dry ice particles may be adjusted by using only one of the meshing length of the screw portions 30a and 30b of the sleeve 30 and the heating by the heater 35.

  As described above, the foreign matter removing apparatus 100 according to the present embodiment can adjust the particle size of the dry ice particles to the submicron order by the flight distance L from the outlet of the nozzle 31 to the chamber 29 and the heating of the chamber 29. Therefore, it is possible to effectively remove the minute foreign matter 50 of less than 50 μm attached to the surface of the substrate 13 or the semiconductor die without damaging the substrate 13 or the semiconductor die.

  Next, a foreign matter removing apparatus 200 according to another embodiment of the present invention will be described with reference to FIG. Parts similar to those of the foreign matter removing apparatus 100 described above with reference to FIGS. 1 to 6 are denoted by the same reference numerals, and description thereof is omitted.

  As shown in FIG. 7, the foreign matter removing apparatus 200 of the present embodiment has an air inlet 25 c on the side surface of the sleeve 30. The foreign matter removing apparatus 200 allows compressed air to flow into the chamber 29 together with gaseous carbon dioxide and dry ice particles, and mixes gaseous carbon dioxide, dry ice particles, and compressed air in the chamber 29, and slits 23. The mixed fluid of compressed air, gaseous carbon dioxide, and dry ice particles is ejected from the substrate to remove the minute foreign matter 50 and the foreign matter 51 from the substrate 13. Since the foreign substance removal apparatus 200 of this embodiment can increase the flow rate of the fluid ejected from the slit 23 as compared with the foreign substance removal apparatus 100 described above, even when the foreign substance 51 larger than the fine foreign substance 50 adheres more. Thus, the minute foreign matter 50 and the foreign matter 51 can be effectively removed. It is also possible to adjust the particle diameter of the dry ice particles ejected from the slit 23 by adjusting the temperature of the air flowing in from the air inlet 25c.

  In the embodiment shown in FIG. 7, it has been described that the air inlet 25 c that allows the compressed air to flow into the sleeve 30 is provided. However, the air inlet 25 c allows the compressed air to flow into the chamber 29 to form gaseous carbon dioxide. As long as it is a position where dry ice particles and compressed air are mixed, they may be placed anywhere, for example, on the lid 22.

  Next, a foreign matter removing apparatus 200 according to another embodiment of the present invention will be described with reference to FIG. Parts similar to those of the foreign matter removing apparatus 100 described above with reference to FIGS. 1 to 6 are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 8, the foreign matter removing apparatus 300 of the present embodiment has a hole 61 communicating with the chamber 29 arranged in a straight line instead of the slit 23 of the foreign matter removing apparatus 100 described with reference to FIGS. 1 to 6. This is a squirt outlet. As shown in FIG. 8, when the cleaning head 20 is reciprocated in the Y direction while jetting a mixed fluid of gaseous carbon dioxide and dry ice particles as shown by an arrow 96 in FIG. The minute foreign matter 50 and the foreign matter 51 in the region B of the substrate 13 shown in FIG. 8 are removed. The foreign matter removing apparatus 300 of the present embodiment has the same effects as the foreign matter removing apparatus 100 described with reference to FIGS. 1 to 6.

  In the foreign matter removing devices 100 and 200 described above, the cleaning head 20 is described as being attached to the arm 28 so as to incline from the vertical direction toward the lid 22, but as shown in FIG. If the cleaning head 20 is configured to be inclined, the cleaning head 20 may be attached to the arm 28 in a vertically standing state.

  In each of the embodiments described above, a mixed fluid of gaseous carbon dioxide and dry ice particles, or a mixed fluid of gaseous carbon dioxide, dry ice particles, and air is directed toward the substrate 13 that is a flat plate member. Although described as spraying, the foreign matter removing apparatus 100, 200, 300 of the present embodiment is, for example, a minute foreign matter 50, foreign matter attached to the surface of a semiconductor wafer, a lead frame in which a semiconductor die is bonded on a substrate, or the like. It can also be applied when removing 51. In addition, the foreign matter removing apparatuses 100, 200, and 300 of each embodiment can be incorporated into an electronic component mounting apparatus such as a die bonding apparatus, a wire bonding apparatus, and a flip chip bonding apparatus. Furthermore, the foreign matter removing apparatuses 100, 200, and 300 according to the present embodiment can be applied to removing foreign matters on the surface of a flat plate member such as glass or film.

  11, 12 Guide rail, 13 Substrate, 20 Cleaning head, 21 Main body, 21b Rear surface, 22 Lid, 22a Flange, 22b Inclined part, 23 Slit, 24 Suction port, 25 Inlet connection pipe, 25a, 30a, 30b, 31a, 31b Threaded part, 25c Air inlet, 26 Suction connection pipe, 27 Connection member, 28 Arm, 29 Chamber, 29a Recessed part, 29b Inclined surface, 30 Sleeve, 31 Nozzle, 31c Restriction part, 35 Heater, 40 Drive part, 45 Stage, 50, foreign matter, 51 foreign matter, 61 holes, 91, 92, 95 arrows, 100, 200, 300 Foreign matter removing device.

Claims (6)

A nozzle that expands a pressurized stream of liquid carbon dioxide and forms solid carbon dioxide particles in the stream by cooling during expansion;
A chamber connected to the nozzle and into which solid carbon dioxide particles flow;
A spout connected to the chamber and ejecting solid carbon dioxide particles toward the surface of the flat plate member;
A foreign matter removing apparatus comprising a suction port disposed adjacent to the jet port,
By changing the distance from the outlet of the nozzle to the chamber to change the flight distance of solid carbon dioxide particles from the outlet of the nozzle to the chamber, particles of solid carbon dioxide particles ejected from the outlet Foreign material removal device that adjusts the diameter to submicron order. The foreign matter removing apparatus according to claim 1,
Including a heater attached to the outer surface of the chamber;
A foreign matter removing apparatus that adjusts the particle diameter of individual carbon dioxide particles ejected from the ejection port by changing a heating amount of the heater. The foreign matter removing apparatus according to claim 1 or 2,
The foreign matter removing apparatus, wherein the jetting port is a slit that communicates with the chamber and jets the carbon dioxide particles in a band shape toward the surface of the flat plate member. The foreign matter removing apparatus according to claim 1 or 2,
The spout is a foreign substance removing device which is a plurality of holes arranged in a straight line in communication with the chamber. The foreign matter removing apparatus according to any one of claims 1 to 4,
The ejection port is a foreign substance removal device that injects the carbon dioxide particles with an inclination toward the suction port. The foreign matter removing apparatus according to any one of claims 1 to 5,
An air inlet for allowing compressed air to flow into the chamber;
The chamber is a foreign matter removing device that mixes the carbon dioxide particles and the compressed air.

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