JP5223549B2 - Coating equipment - Google Patents

Description

  The present invention relates to a coating apparatus for applying a coating liquid by immersing an object to be coated in a coating liquid in an application tank.

In Patent Document 1, an object to be coated is carried into an application tank, and then a coating liquid is supplied into the application tank so that the object to be coated is immersed in the coating liquid. After being immersed for a predetermined time, the coating liquid is applied. A coating apparatus is disclosed in which a coating liquid is applied to an object to be coated by being extracted from a tank.
JP 2007-203145 A

  In the coating apparatus of Patent Document 1, when the coating liquid is extracted from the application tank, excess coating liquid drops from the object to be applied. While the coating liquid is dripping, the object to be coated cannot be taken out from the coating tank. In particular, when the object to be coated has a gap, there is a problem that the coating liquid contained in the gap does not easily escape and it takes a long time to drain the liquid.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a coating apparatus that can shorten the time required for draining an object to be coated.

In the first aspect of the present invention, the air supply hole for flowing air to the outer surface of the object to be coated and the required part of the object to be coated is provided in the coating tank. By blowing air out of the pores, the air can flow on the outer surface of the object to be coated and the required part of the object to be coated. Due to the air blown out from the air intake holes, the outer surface of the object to be coated and a surplus coating liquid that has entered a required portion, for example, a gap, are flowed by the air flow and removed from the object to be coated.
In addition, since the first tank and the second tank can be aligned by moving in the lateral direction, the work of storing the object to be coated in the coating tank is facilitated. Moreover, since the coating liquid application unnecessary part of a to-be-coated object can be pinched | interposed between a 1st tank and a 2nd tank, the structure for hold | maintaining a to-be-coated object in an application tank becomes easy.

In the invention of claim 2, since the drainage hole and the exhaust hole are shared by the multi-function hole formed at the bottom of the coating tank, the extra coating liquid removed from the object to be coated and dripped into the coating tank Can be quickly discharged from the coating tank.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 6 shows an example of an object to be applied, which is an object to which the coating liquid is applied. The object to be coated is a semiconductor device 5 configured by sandwiching two semiconductor chips 1 and 2 between two heat sinks 3 and 4. FIG. 6 shows a state in which the semiconductor chips 1 and 2 are soldered to one heat sink 3. After that, the other heat sink 4 is soldered to the semiconductor chips 1 and 2, and two semiconductor chips 1 and 2 are shown. A semiconductor device 5 sandwiched between the heat sinks 3 and 4 is configured.

  The heat sinks 3 and 4 are configured as islands of the lead frames 6 and 7, respectively. One lead frame 6 integrally includes a terminal 8, a lead 9, a tie bar 10 for connecting the lead 9 to the heat sink 3, and the like integrally with the heat sink 3. The other lead frame 7 has only terminals 11. In these two lead frames 6 and 7, the terminals 8 and 11, the lead 9 and the tie bar 10 are bent at the connection portions with the heat sinks 3 and 4, whereby the heat sinks 3 and 4 are connected to the semiconductor chips 1 and 2. When soldered to both sides, the terminals 8 and 11, the lead 9 and the tie bar 10 are located on the same plane.

  The semiconductor chip 1 is connected to the leads 9 and bonding wires 12. Finally, the semiconductor device 5 is resin-sealed so as to expose the outer surfaces of the heat sinks 3 and 4, and excess portions of the lead frames 6 and 7 are cut to remove the leads 9 from the sealing resin. It is configured as a resin-encapsulated semiconductor device in which terminals 8 and 11 protrude.

  A coating liquid is applied to the semiconductor device 5 at an appropriate time before resin sealing. FIG. 1 shows a coating apparatus 13 for applying a coating liquid. The coating apparatus 13 is mainly composed of an application tank 14 that stores the coating liquid and immerses the semiconductor device 5. The application tank 14 includes a fixed tank (first tank) 15 fixed at a fixed position, and a movable tank (second tank) that is driven by a driving mechanism (not shown) and moves in a direction in contact with and away from the fixed tank 15. Tank) 16.

  The fixed tank 15 and the movable tank 16 have recesses 15a and 16a, respectively, for constituting a liquid storage chamber 17 that stores the coating liquid when they are abutted against each other. The fixed tank 15 has a rectangular frame 19 that is fastened and fixed by a screw 18 shown in FIG. A through-groove 20 having a convex cross section is formed continuously on the lower side and the left and right sides of the frame body 19, and a packing 21 having a convex cross section is fitted into the through-groove 20. The tip 21 a of the packing 21 protrudes outward from the through groove 20. When the movable tank 16 is abutted against the fixed tank 15, the tip 21 a of the packing 21 is in contact with the movable tank 16 and is movable with the fixed tank 15. The space between the butt surfaces of the tank 16 is sealed.

  A multifunctional hole 22 is formed in one of the fixed tank 15 and the movable tank 16, for example, a lower wall portion of the fixed tank 15, and one end of the multifunctional hole 22 is at the back of the inner bottom portion of the recess 15 a. Are opened at the corners. A connecting pipe 23 is connected to the other end opening of the multi-function hole 22, and the tip side is bifurcated. One branch pipe 23 a of the connection pipe 23 is connected to the liquid supply / discharge pipe 27 immersed in the coating liquid in the liquid storage tank 26 through the two first on-off valves 24 and the second on-off valve 25. Has been. A liquid supply / discharge cylinder device (liquid supply / discharge means) 28 is connected between the first on-off valve 24 and the second on-off valve 25. On the other hand, the other branch pipe 23b is connected to a gas-liquid separation tank (gas-liquid separation means) 30 via a third on-off valve 29. The gas-liquid separation tank 30 is further connected to an intake device such as a vacuum suction machine. (Intake means) 31 is connected.

  The liquid supply / discharge cylinder device 28 is configured such that a piston 28b is housed in a cylinder tube 28a so as to be able to reciprocate. The first on-off valve 24, the second on-off valve 25, and the third on-off valve 29 are opened and closed. The liquid supply operation for supplying the coating liquid in the liquid storage tank 26 to the liquid storage chamber 17 of the application tank 14 and the drainage liquid for discharging the coating liquid in the liquid storage chamber 17 into the liquid storage tank 26 are selected. The operation can be selected.

  That is, when the piston 28b is moved in the direction of arrow A by a driving device (not shown) with the first on-off valve 24 closed and the second on-off valve 25 opened, the coating liquid in the liquid storage tank 26 is transferred to the cylinder tube 28a. Inhaled. When the piston 28b is moved in the direction of arrow B by a driving device (not shown) with the first on-off valve 24 opened and the second on-off valve 25 and the third on-off valve 29 closed, the inside of the cylinder tube 28b The coating liquid is supplied into the liquid storage chamber 17 of the application tank 14 through the multifunction hole 22 (the liquid supply operation).

  On the contrary, when the piston 28b is moved in the direction of arrow A by a driving device (not shown) with the first on-off valve 24 opened and the second on-off valve 25 and the third on-off valve 29 closed, the liquid storage chamber 17 The coating liquid inside is sucked into the cylinder tube 28b from the multi-function hole 22. Then, when the piston 28b is moved in the arrow B direction by a driving device (not shown) with the first on-off valve 24 closed and the second on-off valve 25 opened, the coating liquid in the cylinder tube 28a is stored in the liquid storage tank 26. Is supplied to the inside (drainage operation).

  The intake device 31 performs an intake operation of sucking air in the liquid storage chamber 17 from the multi-function hole 22 by closing the first on-off valve 24 and opening the third on-off valve 29. From the above, the multi-function hole 22 discharges the air in the liquid supply hole for supplying the coating liquid into the liquid storage chamber 17, the drain hole for discharging the coating liquid from the liquid storage chamber 17, and the air in the liquid storage chamber 17. It also functions as an exhaust hole.

  A plurality of ventilation holes (air supply holes) 32 are formed in the upper wall portion of the fixed tank 15. One end of each of these vent holes 32 is opened on the back side of the inner upper surface of the recess 15a, and the other end is opened to the outside. Further, as shown in FIG. 2, a first air supply path (air supply hole) 33, a second air supply path (air supply hole) 34, and a third air supply path 33 are provided in the left side wall portion and the right side wall portion of the fixed tank 15. An air supply path (air supply hole) 35 is formed. Here, when the concave portion 15a is divided into three stages in the vertical direction, one end of the first air supply path 33 opens at the upper step of the inner surface of the concave portion 15a, and one end of the second air supply path 34 is the concave portion 15a. The one end of the third air supply path 35 is opened at the lower step on the inner side surface of the recess 15a. The other ends of the first air supply path 33, the second air supply path 34, and the third air supply path 35 are all connected to a compressed air supply source such as a compressor via an on-off valve (not shown). Yes.

  On the other hand, as shown in FIG. 3, a fourth air supply path (air supply hole) 37 is formed in the upper surface plate 36 constituting the upper surface portion of the movable tank 16. As shown in FIG. 1, the fourth air supply path 37 has one end branched into a plurality of branches, and each branch end is open on the inner surface of the inner surface of the recess 16a. The other end of the fourth air supply path 37 is also connected to the compressed air supply source via the above-described on-off valve (not shown).

  The semiconductor device 5 is accommodated in the liquid storage chamber 17 in a state as shown in FIGS. 1 to 3, but the first air supply path 33 has two heat sinks 3 for supplying compressed air to the semiconductor device 5. , 4 blows out compressed air sideways toward the upper part of the gap 38, and the second air supply path 34 blows out compressed air sideways toward the intermediate part of the gap 38 between the two heat sinks 3, 4. The third air supply path 35 blows out compressed air laterally toward the lower portion of the gap 38 between the two heat sinks 3 and 4, and the fourth air supply path 37 connects the one heat sink 3 and the movable tank 16. Compressed air is blown downward between the inner surface of the recess 16a. Further, when the air suction device 31 sucks air in the liquid storage chamber 17, the vent hole 32 sucks outside air and compresses it between the other heat sink 4 and the inner surface of the recessed portion 15 a of the fixed tank 15. The air is blown downward.

  Next, the operation of the above configuration will be described. The semiconductor device 5 transported to the vicinity of the coating device 13 by the conveyor is fixed in a separated state by gripping, for example, the tip portion of the tie bar 10 and the tip portions of the terminals 8 and 11 of the lead frame 6 by a robot (not shown). It is conveyed between the tank 15 and the movable tank 16. Thereafter, the movable tank 16 is moved toward the fixed tank 15 by a driving mechanism (not shown).

  In this movement process, the movable tank 16 contacts the semiconductor device and moves together with the robot to the fixed tank 15 side. At this time, the semiconductor device 5 is positioned relative to the movable tank 16 by fitting a predetermined positioning mechanism, for example, a positioning pin provided on the movable tank 16 side and a positioning hole (none of which is shown) provided on the semiconductor device 5 side. Is made. The leading end side of the tie bar 10 of the lead frame 6 of the semiconductor device 5 thus positioned and the leading end side of the terminals 8 and 11 of the lead frames 6 and 7 are sandwiched between the butted surfaces of the fixed tank 15 and the movable tank 16, A portion between the sandwiching portions, that is, a main portion of the semiconductor device 5 in a form in which the two semiconductor chips 3 are sandwiched between the two heat sinks 3 and 4 is accommodated in the liquid storage chamber 17. Note that the seal between the abutting surfaces of the fixed tank 15 and the movable tank 16 is maintained by the tip 21 a of the packing 21 following the tip of the tie bar 10 and the tips of the terminals 8 and 11.

  When the movable tank 16 is abutted against the fixed tank 15, the liquid supply operation by the liquid supply / discharge cylinder device 28 is repeated a plurality of times, and a predetermined amount of coating liquid is supplied into the liquid storage chamber 17. The semiconductor device 5 is immersed in the coating liquid in the liquid storage chamber 17. After the semiconductor device 5 is immersed in the coating liquid for a predetermined time, the liquid discharging operation by the liquid supply / discharge cylinder device 28 is repeated a plurality of times, and the coating liquid in the liquid storage chamber 17 is returned to the liquid storage tank 26.

  When the coating liquid is discharged from the liquid storage chamber 17, excess coating liquid remains on the inner surface of the liquid storage chamber 17 (the inner surface of the concave portion 15 a and the inner surface of the concave portion 16 a), and also on the surface of the semiconductor device 5. The coating liquid remains attached. In particular, a large amount of coating liquid remains in the gap 38 between the two heat sinks 3 and 4 that are sandwiched between the two surfaces due to surface tension, as indicated by C in FIG.

  Thereafter, the first on-off valve 24 is closed and the third on-off valve 29 is opened, and the intake device 31 is driven in this state. At the same time, compressed air is supplied from the compressed air supply source to the first air supply path 33 to the third air supply path 35 and the fourth air supply path 37. The intake air amount of the intake device 31 is determined to be larger than the air amount discharged from the first air supply passage 33 to the third air supply passage 35 and the fourth air supply passage 37.

  Then, the air in the liquid storage chamber 17 is sucked through the multi-function hole 22 by the intake device 31, and the pressure in the liquid storage chamber 17 is reduced, so that the outside air is sucked into the liquid storage chamber 17 from the vent hole 32. Then, the intake air mainly flows through the gap between the heat sink 4 and the inner surface of the concave portion 15a of the fixed tank 15 toward the multi-function hole 22, and in the course of the circulation, excess coating liquid on the surface of the heat sink 4 Or the coating liquid adhering to the inner surface of the recess 15a is poured off.

  The air blown out from the first air supply path 33, the second air supply path 34, and the third air supply path 35 is a necessary portion inside the semiconductor device 5, that is, a gap 38 between the heat sinks 3 and 4. Among these, the coating liquid remaining on the semiconductor chip 1, the coating liquid remaining between the semiconductor chips 1 and 2, and the coating liquid remaining below the semiconductor chip 2 are blown off. Further, the air blown out from the fourth air supply path 37 mainly flows downward through the gap between the heat sink 3 and the inner surface of the concave portion 16a of the movable tank 16, and the excess coating liquid on the outer surface of the heat sink 3 and the concave portion 16a. The coating liquid adhering to the inner surface of is blown off.

  The air sucked from the air holes 32 and the air blown from the first air supply passage 33 to the third air supply passage 35 and the fourth air supply passage 37 are the surface of the semiconductor device 5 as described above. The excess coating liquid adhering to the liquid and the coating liquid adhering to the inner surface of the liquid storage chamber 17 flow into the gas-liquid branch tank 29 from the multi-function hole 22 while blowing. The air that has flowed into the gas-liquid separation tank 30 carries the coating liquid, but the coating liquid and air are separated in the gas-liquid separation tank 30 and the coating liquid is stored in the gas-liquid separation tank 30, and the air Only the air is sucked into the intake device 31. The coating liquid stored in the gas-liquid separation tank 30 is eventually returned to the liquid storage tank 26.

  In this way, after the excess coating liquid adhering to the semiconductor device 5 and the liquid storage chamber 17 is removed, the movable tank 16 is separated from the fixed tank 15. Then, the semiconductor device 5 coated with the coating liquid is transported to the next process by a robot (not shown). Although the robot may seem to hold the semiconductor device 5 during application of the coating liquid to the semiconductor device 5, the robot is provided with a plurality of application tanks 14, and the semiconductor device 5 is attached to each application tank 14. Once transported, it is possible to sequentially perform operations such as transporting the semiconductor device 5 after coating to another coating tank 14 or transporting the semiconductor device 5 that has been coated in another coating tank 14 to the next process. It becomes.

  As described above, according to the present embodiment, after the coating liquid is applied to the semiconductor device 5, the excess coating liquid in the semiconductor device 5 and the liquid storage chamber 17 is passed through the first air supply path 33 to the fourth air supply path. Since it can be forcibly excluded by the compressed air ejected from the air passage 37 or the outside air sucked into the liquid storage chamber 17 from the vent hole 32, the semiconductor device 5 can be drained and the liquid storage chamber 17 can be removed. It can be done in a short time.

  Further, since the coating liquid that has been drained and has flowed to the bottom of the liquid storage chamber 17 is conveyed to the air flow flowing out from the multi-function hole 22 and quickly removed, the movable tank 16 is quickly separated from the fixed tank 15. In addition, when separated, the coating liquid does not flow out of the recesses 15a and 16a.

The present invention is not limited to the embodiment described above and shown in the drawings, and can be expanded or changed as follows.
It is good also as an air supply path which blows out compressed air instead of the ventilation hole 32. FIG.
The fixed tank 15 may be configured to be movable in the same manner as the movable tank 16.
The object to be coated is not limited to the semiconductor device 5.
The air blown out from the first air supply path 33 to the third air supply path 35 may remove excess coating liquid that has entered the recessed portion with a bottom depending on the object to be coated. .

The cross-sectional front view of the coating apparatus which shows one Embodiment of this invention and is shown with a piping system Longitudinal side view of a fixed tank along the AA line in FIG. Longitudinal side view of movable tank along line II in FIG. Exploded perspective view of fixed tank Longitudinal section of semiconductor device Disassembled perspective view of semiconductor device

Explanation of symbols

  In the drawings, 5 is a semiconductor device (object to be coated), 13 is a coating device, 14 is a coating tank, 15 is a fixed tank (first tank), 16 is a movable tank (second tank), and 17 is a liquid storage chamber. , 21 is a packing, 22 is a multi-function hole, 26 is a liquid storage tank, 28 is a liquid supply / discharge cylinder device, 30 is a gas-liquid separation tank, 31 is an intake device, 32 is a vent (air supply hole), and 33 to 35 are 1st-3rd air supply path (air supply hole) and 37 show the 4th air supply path (air supply hole).

Claims (2)

The coating object is supplied by supplying a coating liquid into the coating tank in which the coating object is stored, immersing the coating object in the coating liquid, and then discharging the coating liquid from the coating tank. In a coating apparatus for applying a coating liquid to
A drainage hole formed at the bottom of the application tank, for discharging the coating liquid after immersing the object to be applied from the application tank,
An air supply hole formed in the application tank, and after the coating liquid is discharged from the application tank, for flowing air to an outer surface of the application object and a required portion of the application object,
An exhaust hole that is formed at the bottom of the application tank and discharges air blown into the application tank from the air supply hole ;
The coating tank comprises a first tank and a second tank that can be separated in a lateral direction . 2. The coating apparatus according to claim 1, wherein the drainage hole and the exhaust hole are shared by a multi-function hole formed in a bottom portion of the coating tank.

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