JP4962445B2 - Substrate unloader - Google Patents

Description

  The present invention relates to a substrate carry-out device for carrying a substrate on which electronic components are mounted to a subsequent process.

Conventionally, when an electronic component and a substrate are heated and bonded while applying thermal energy to the bonding portion, the substrate is preheated before mounting in order to suppress generation of cracks and warpage of the substrate due to a sudden temperature change. A mounting apparatus having a function of slowly cooling after mounting has been proposed (see Patent Document 1).
Japanese Patent No. 3857949

  As a result of focusing on cracks and warpage generated in the substrate, the mounting apparatus disclosed in Patent Document 1 is configured to perform temperature management of the substrate by heating the substrate only from below, so that it is mounted on the upper surface side of the substrate. There is no active temperature control for electronic components. The heated electronic component and the substrate are bonded in a state of thermal expansion compared to that at normal temperature, but the electronic component and the substrate have different coefficients of thermal expansion due to differences in the materials, so the temperature of both the electronic component and the substrate after mounting is different. If this is not properly controlled, stress concentrates on the joint and may cause joint failure such as cracks and fractures.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a board carry-out device that can maintain the temperature of an electronic component and a board raised during mounting even after mounting.

The substrate unloading device according to claim 1 is a substrate unloading device for unloading the substrate on which the electronic component is thermocompression-bonded in the mounting table to a subsequent process, and is disposed downstream of the mounting table to transfer the substrate to the subsequent process. A substrate transfer device for carrying out to a carry-out position, and a substrate transfer device for transferring a substrate after mounting electronic components from the mounting table to the substrate transfer device. The substrate transfer device includes a pair of left and right conveyor belts, and a conveyor belt The substrate transfer device includes a heat block that heats the substrate from above, and the heat block is upstream of the substrate transport direction. The first region and the second region on the downstream side, and the first region and the second region can be independently adjusted in temperature, and the substrate is heated from above by the first region. Naga After being transferred to the substrate transport apparatus, it is conveyed toward the unloading position on subsequent steps in a state of being heated from both upper and lower directions by the second region and the post-heat block.

  By placing the mounted substrate in a heated state, it is possible to avoid a rapid temperature drop due to heat dissipation after mounting, and to transfer to a subsequent process while maintaining a good bonding state between the electronic component and the substrate.

  Embodiments of the present invention will be described with reference to the drawings. 1 is a configuration diagram of a substrate carry-out apparatus according to an embodiment of the present invention, FIG. 2 is a side view of a heat block according to the embodiment of the present invention, and FIG. 3 is a partially enlarged view of the substrate carry-out apparatus according to the embodiment of the present invention. FIG. 4, FIG. 4 and FIG. 5 are diagrams for explaining the operation of the substrate carry-out apparatus according to the embodiment of the present invention.

First, the configuration of the substrate carry-out device will be described with reference to FIG. The board carried out to the subsequent process by the board carrying-out device 1 is the board 4 on which the electronic component 3 is thermocompression bonded by the mounting table 2. The mounting table 2 can be moved horizontally by the linear motion tables 6 and 7 installed on the base 5 of the substrate carry-out device 1. A mounting head 8 is disposed above the mounting table 2. The mounting head 8 attracts the electronic component 3 to the lower end and descends toward the substrate 4 placed on the upper surface of the mounting table 2, and applies pressure to the solder bumps 9 of the electronic component 3 on the electrodes 10 on the upper surface of the substrate 4. Touch while touching. The solder bumps 9 are melted by the heat generated by the heater 11 built in the mounting head 8 and the heater 12 built in the mounting table 2, and the electronic component 3 and the substrate 4 are connected. The plurality of electronic components 3 are mounted on the substrate 4 while sequentially changing the position of the substrate 4 placed on the mounting table 2 with respect to the mounting head 8 by driving the linear motion tables 6 and 7.

  A substrate transfer device 20 is disposed on the downstream side of the mounting table 2 with respect to the transfer direction of the substrate 4. The substrate transport device 20 is a device that transports the substrate 4 on which the electronic component 3 is thermocompression-bonded by the mounting table 2 to a carry-out position for a subsequent process. This unloading position is a position where the substrate 4 is delivered to the substrate transfer device 100 arranged in a subsequent process, and the substrate unloading device 1 delivers the substrate 4 to the transfer device 100 at this unloading position.

  The substrate transfer device 20 includes a pair of conveyor belts 21, pulleys 22 and 23 that stretch the conveyor belt 21 horizontally, a driving roller 24 that supplies driving force to the conveyor belt 21, and a substrate 4 that is being transferred from below. The post heat block 25 is moved up and down between a post heat block 25 serving as a lower heating means for heating and a pair of conveyor belts 21 stretched horizontally by pulleys 22 and 23, and the upper surface (heating surface) of the post heat block 25 Is conveyed by a cylinder mechanism 26 that adjusts the distance (clearance) between the substrate 4 and the bottom surface of the substrate 4, a cylinder mechanism 27 that adjusts the height of the pair of conveyor belts 21, and a pair of conveyor belts 21 that are horizontally stretched. It is composed of a pair of transport guides 28 that form a transport path for the substrate 4 therebetween.

  The both ends of the substrate 4 are respectively placed on the horizontal portions of the pair of conveyor belts 21 and are conveyed in the length direction by driving the pair of conveyor belts 21. The post heat block 25 has substantially the same length as the horizontal portion of the pair of conveyor belts 21 stretched by the pulleys 22 and 23, and can always heat the substrate 4 being conveyed from below.

  The substrate transfer device 30 includes an arm 31 that extends in the transport direction of the substrate 4, a suction pad 32 that is attached downward to the arm 31, and a heat block 33 that is also attached to the arm 31. The suction pad 32 is connected to a vacuum generation source (not shown) to suck and hold the upper surface of the substrate 4. One each is arranged at a position corresponding to the four corners of the substrate 4. The heat block 33 is disposed between the suction pads 32 that are spaced apart in the width direction of the substrate 4. The length of the heat block 33 in the length direction of the substrate 4 is determined in consideration of at least the length of the substrate 4 having the maximum length, and the total length of the substrate 4 sucked by the suction pad 32 is the heat block. It fits within the entire length of 33. It is desirable that the length of the conveyor belt 21 is approximately the same as the horizontal portion.

  The lower surface of the heat block 33 is a heating surface that heats the mounted substrate 4 from above. As shown in FIG. 2, the heat block 33 is divided into two regions in the conveyance direction of the substrate 4. The upstream side with respect to the transport direction of the substrate 4 is the first region 33a, and the downstream side thereof is the second region 33b. The lower surface of the first region faces the upper surface (including the mounted electronic component) of the substrate 4 sucked by the suction pad 32, and heats the substrate 4 from above. The stopper 33 c provided in the first region 33 a adjusts the distance (clearance) between the heating surface and the upper surface of the substrate 4.

The first region 33a faces the upper surface of the substrate 4 at a distance corresponding to the clearance c1 adjusted by the stopper 33c, and heats the substrate 4 being moved from the mounting table 2 to the substrate transport device 20 from above. The substrate 4 is transferred to the conveyor belt 21 of the substrate transfer device 20 while being heated from above by the first region 33a, and after being transferred to the conveyor belt 21, the substrate 4 is heated from above by the second region 33b. It is transported toward the unloading position to the process. The distance (clearance) between the upper surface of the substrate 4 being transferred and the second region 33b is c2 which is larger than c1. The temperature of the heat block 33 can be adjusted independently in the first region 33a and the second region 33b. The first region 33a and the second region 33b are adjusted according to the difference between the clearances c1 and c2, and the heating effect of the substrate 4 by the heat block 33 is constant regardless of the difference in clearance. Since the heat block 33 indirectly heats the substrate 4 by radiant heat, the temperature of the second region 33b having a larger clearance from the upper surface of the substrate 4 is adjusted to be higher than the temperature of the first region 33a. The temperature of the substrate 4 is not lowered even when the clearance is increased.

  The second region 33b may be subdivided into a plurality of regions, and each region may be configured to be capable of temperature management independently. If comprised in this way, the detailed temperature management according to the behavior of the temperature of the board | substrate 4 in conveyance will be attained, and it is especially effective, so that the conveyance distance by the board | substrate carrying-out apparatus 20 becomes long.

  The feed screw mechanism 40 includes a horizontal screw 41 disposed above the mounting table 2 and the substrate transfer device 20, a horizontal motor 42 that rotates the horizontal screw 41 around the horizontal axis, and a screw screwed on the horizontal screw 41. A horizontal nut 43 that moves in the horizontal direction as the horizontal screw 41 rotates, a vertical screw 44 disposed on the horizontal nut 43, a vertical motor 45 that rotates the vertical screw 44 about a vertical axis, The vertical nut 46 is engaged with the vertical screw 44 and moves in the vertical direction as the vertical screw 44 rotates.

  The arm 31 attached to the vertical nut 46 can move in the horizontal direction by the rotation of the horizontal screw 41, and can move in the vertical direction by the rotation of the vertical screw 44. The substrate transfer device 30 mainly composed of the arm 31 sucks the mounted substrate 4 with the suction pad 32, moves it from the mounting table 2 to the substrate transport device 20, and places it on the post heat block 25.

  Next, heating of the substrate during conveyance will be described with reference to FIGS. The board | substrate 4 transferred to the board | substrate conveyance apparatus 20 is conveyed by the drive of a pair of conveyor belt 21 in which both sides were mounted. During the transfer of the substrate 4, the substrate transfer device 30 is positioned above the substrate 4 and maintains a predetermined distance between the lower surface of the heat block 33 and the upper surface of the substrate 4 (including the electronic component 3). The post heat block 25 is adjusted in height so that the upper surface (heating surface) is positioned at a predetermined distance from the lower surface of the substrate 4.

  Since the substrate carry-out device 1 heats the substrate 4 being conveyed by the radiant heat of the heat block 33 and the post heat block 25, the airtightness around the substrate 4 greatly affects the thermal efficiency. Here, as shown in FIG. 3, the substrate transfer device 30 is provided with an upper cover 35 that covers the upper side and the side of the heat block 33, and the substrate transfer device 20 is provided with a lower cover 29 that covers the upper cover 35 from the side. When the substrate 4 is transported, the upper cover 35 and the lower cover 29 overlap to form a highly airtight space 36 around the substrate 4.

  Next, the substrate transfer operation performed by the substrate carry-out apparatus will be described with reference to FIGS. In FIG. 4A, the substrate transfer device 30 transfers the mounted substrate 4 from the mounting table 2 to the substrate transfer device 20. The electronic component 3 is mounted on the upper surface of the substrate 4, and both the electronic component 3 and the substrate 4 are heated by being heated from above by the heat block 33. The post heat block 25 has moved to a position where the upper surface thereof is above the plane portion of the conveyor belt 21, and the substrate transfer device 30 places the substrate 4 directly on the post heat block 25. The post heat block 25 heats the substrate 4 from below by direct heating that is more efficient than radiant heating.

The mounted substrate 4 is heated from above while moving from the mounting table 2 to the substrate transfer device 20, and immediately after being moved to the substrate transfer device 20, in addition to being directly heated from below. is there. Since the moving substrate 4 is only heated from above, it is desirable to keep the moving distance as short as possible in order to maintain the temperature of the substrate 4 and the electronic component 3. Therefore, here, the substrate transfer device 20 is set to the same height as the mounting table 2 so as to shorten the ascending / descending distance of the substrate transfer device 30.

  Since the substrate transfer device 20 at the same height as the mounting table 2 needs to have the same height as the transfer device 100 at a higher position, first the substrate transfer device as shown in FIG. Next, as shown in FIG. 5A, the substrate transfer device 20 is raised and the height of the conveyor belt 21 is adjusted to the height of the conveyor belt 101 of the transfer device 100. The substrate transfer device 30 that rises first is high enough that the upper surface of the substrate 4 (including the mounted electronic component 3) does not come into contact with the suction pad 32 or the heat block 33 when the substrate transport device 20 rises. Keep rising.

  Since the distance between the substrate 4 and the heat block 33 increases from when the substrate transfer device 30 starts to rise until the substrate transfer device 20 completes the rise, the thermal efficiency of heating the substrate 4 from above decreases. However, since the post heat block 25 is directly heated from below during that period, the temperature of the substrate 4 and the electronic component 3 does not decrease.

  It is also possible to raise the substrate transfer device 30 and the substrate transfer device 20 at the same time while maintaining a constant interval. In this case, since the substrate 4 can be maintained in a heated state from above even during the rise, the temperature of the substrate 4 and the electronic component 3 can be more effectively maintained as compared with the case where the substrate 4 is raised with a time difference.

  In FIG. 5B, the post heat block 25 is lowered and the substrate 4 is transferred onto the conveyor belt 21. Since the substrate 4 being conveyed toward the conveying device 100 by the conveyor belt 21 is in a state of being indirectly radiatively heated from both the upper and lower directions by the heat block 33 and the post heat block 25, the electronic component 3 mounted on the upper surface is attached. The entire temperature is maintained including.

  In this embodiment, the position where the electronic component 3 is mounted on the substrate 4 by thermocompression bonding, that is, the position where the mounting table 2 is arranged is the first position, and the substrate transfer device 20 is transferred from the substrate transfer device 30 to the substrate 4. The position for receiving is the second position. The substrate transfer device 30 functions as a first substrate moving means for moving the substrate 4 on which the electronic component 3 is mounted at the first position to the second position, and the substrate transfer device 20 is moved from the second position. It functions as a second substrate moving means for moving the substrate 4 to a third position which is a carry-out position to a subsequent process. The heat block 33 provided in the substrate transfer device 30 functions as an upper heating unit that heats the substrate 4 from above, and heats the substrate 4 being moved from the first position to the second position from above. The first region 33a and the second region 33b for heating the substrate 4 being moved from the second position to the third position from above are provided independently for temperature control.

  According to the present invention, the mounted substrate 4 is heated from above by the heat block 33 while being transferred to the substrate transfer device 20 by the substrate transfer device 30 and is transferred toward the unloading position by the substrate transfer device 20. The space is maintained in a state heated by the heat block 33 and the post heat block 25 from both the upper and lower directions. Therefore, according to the substrate carry-out device 1, it is possible to avoid a temperature drop between the electronic component 3 and the substrate 4 that are joined in the expanded state due to heating during mounting. It can be transferred to a subsequent process while maintaining good condition.

  The present invention is useful in the field of mounting electronic components on a substrate by thermocompression bonding.

Configuration diagram of a substrate carry-out device according to an embodiment of the present invention Side view of the heat block of the embodiment of the present invention The partially enlarged view of the board | substrate carrying-out apparatus of embodiment of this invention Operation | movement explanatory drawing of the board | substrate carrying-out apparatus of embodiment of this invention Operation | movement explanatory drawing of the board | substrate carrying-out apparatus of embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate unloading device 3 Electronic component 4 Substrate 20 Substrate transport device 25 Post heat block 30 Substrate transfer device 33 Heat block 33a 1st area | region 33b 2nd area | region

Claims (1)

A substrate carry-out device for carrying out a substrate on which an electronic component is thermocompression-bonded in a mounting table to a subsequent process, the substrate carrying device being arranged on the downstream side of the mounting table and carrying the substrate to a carry-out position to the subsequent process; A substrate transfer device for transferring a substrate after mounting electronic components from the mounting table to the substrate transfer device. The substrate transfer device moves up and down between a pair of left and right conveyor belts and the conveyor belt from below. Having a post-heat block to heat,
The substrate transfer apparatus includes a heat block that heats the substrate from above. The heat block includes a first region on the upstream side and a second region on the downstream side with respect to the substrate transport direction. The temperature of the first region and the second region can be adjusted independently, and the substrate is transferred to the substrate transport apparatus while being heated from above by the first region, and then the second region and the post heat block The substrate unloading apparatus, wherein the substrate unloading apparatus is transported toward the unloading position to a subsequent process while being heated from both the upper and lower directions .

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