JP4884142B2 - Electronic component mounting head and electronic component mounting method - Google Patents

Description

  The present invention relates to an electronic component mounting head for mounting an electronic component on a printed circuit board and an electronic component mounting method using the electronic component mounting head.

  Conventionally, an electronic component mounting head and an electronic component mounting method described in Patent Document 1 are known. The electronic component mounting head includes a suction nozzle that mounts a bare chip on which a bump (projecting electrode) is formed on a printed circuit board, and a head body that can move the suction nozzle perpendicular to the printed circuit board. In this electronic component mounting method, cream solder is previously attached to an electrode pad of a printed circuit board by printing, and then the suction nozzle is lowered and the bare chip is positioned and placed on the printed circuit board. Then, the solder paste is melted and solidified to join the bumps (protruding electrodes) of the bare chip and the electrode pads of the printed board. According to the electronic component mounting head and the electronic component mounting method, the wiring length can be shortened compared to the wire bonding method, and the device can be reduced in size and weight.

An electronic component mounting head and an electronic component mounting method described in Patent Document 2 are also known. The electronic component mounting head includes a suction nozzle that mounts a bare chip on a printed circuit board, and a head body that can move the suction nozzle perpendicular to the printed circuit board. In this electronic component mounting method, after a sealing agent is applied between electrode pads on a printed circuit board, the suction nozzle is lowered to bring the bare chip bumps (protruding electrodes) into contact with the printed circuit board electrode pads. Then, while pressing the bare chip against the printed circuit board, ultrasonic vibration is applied to the bumps (projecting electrode), thereby joining the bump (projecting electrode) of the bare chip and the electrode pad of the printed circuit board. According to the electronic component mounting head and the electronic component mounting method, the wiring length can be shortened as compared with the wire bonding method, and the device can be reduced in size and weight.
JP 2003-282630 A JP 2002-83839 A

  However, in the electronic component mounting head and the electronic component mounting method disclosed in Patent Document 1, pressure is normally applied to the bare chip when the bare chip is placed on the printed board. In particular, in a bare chip having a large number of bumps (protruding electrodes), poor bonding is likely to occur, and the bare chip is pressed against the printed circuit board. However, due to the viscosity of the cream solder applied to the electrode pads on the printed circuit board, there is a possibility that the bumps (protruding electrodes) on the bare chip are displaced from the predetermined positions on the electrode pads on the printed circuit board. Therefore, in the electronic component mounting head and the electronic component mounting method disclosed in Patent Document 1, it may take time to position the bare chip at a predetermined position on the printed circuit board.

  In the electronic component mounting head and the electronic component mounting method disclosed in Patent Document 2, when the bare chip bumps (protruding electrodes) and the electrode pads of the printed circuit board are brought into contact with each other, the sealing agent is used to form the bumps (protruding electrodes) and the electrode pads. The bumps (protruding electrodes) of the bare chip may be displaced from the predetermined positions of the electrode pads of the printed circuit board due to the viscosity of the sealant. Therefore, even with the electronic component mounting head and the electronic component mounting method disclosed in Patent Document 2, it may take time to position the bare chip at a predetermined position on the printed circuit board.

  The present invention has been made in view of the conventional problems and provides an electronic component mounting head and an electronic component mounting method capable of positioning an electronic component on a printed circuit board stably and in a short time. is there.

In order to solve the above-described problem, the electronic component mounting head according to claim 1 is characterized in that an electronic component is sucked at a tip portion and the electronic component is mounted on a printed circuit board, and the suction nozzle is attached to the suction nozzle. An electronic component mounting head comprising a head body movable perpendicularly to a printed circuit board, wherein an upper end is fixed to the head body, and a lower end is slidably mounted on the head body and can contact the suction nozzle When the piezo element and the suction nozzle that sucks the electronic component at the tip end are moved perpendicularly to the printed board by the head body, the adhesive applied to the printed board and / or the electronic component and the electronic An input circuit connected to the piezo element to cause the piezo element to serve as a sensor for detecting contact with a component or the printed circuit board; and the adhesive When the contact between the electronic component and the printed circuit board is detected, the piezoelectric element is vibrated perpendicularly to the printed circuit board and the suction nozzle is vibrated, thereby joining the electronic component and the printed circuit board. And an output circuit connected to the piezo element in order to cause the piezo element to play a role as an actuator for removing the adhesive .

  The electronic component mounting head according to a second aspect is characterized in that, in the first aspect, the adhesive is cream solder.

  A feature of the electronic component mounting head according to claim 3 is that, in claim 1, the adhesive is a sealant.

  The electronic component mounting method according to claim 4 is characterized in that, in the electronic component mounting method for mounting an electronic component on a printed circuit board, an adhesive application step of applying an adhesive to the printed circuit board or / and the electronic component; A suction nozzle lowering process in which a suction nozzle that sucks an electronic component at its tip is moved vertically with respect to the printed circuit board, and a contact that detects contact between the adhesive and the electronic component or the printed circuit board by a piezo element. A detecting step, a vibration applying step of applying vibration perpendicular to the printed circuit board to the electronic component by the piezo element, and removing the adhesive from a joint portion between the electronic component and the printed circuit board; A bonding step of bonding the component to the printed circuit board.

  In the electronic component mounting head according to claim 1, between the suction nozzle and the head body, the contact between the printed circuit board or / and the adhesive applied to the electronic component and the electronic component or the printed circuit board is detected. The piezoelectric device includes a piezoelectric element that applies vibrations perpendicular to the printed circuit board to the electronic component to remove the adhesive from the joint between the electronic component and the printed circuit board. Therefore, the adhesive can be eliminated from the joint between the electronic component and the printed board, and the joint between the electronic component and the printed board can be prevented from shifting. Therefore, according to this electronic component mounting head, the electronic component can be positioned on the printed board stably and in a short time.

  In the electronic component mounting head according to the second aspect, the adhesive is cream solder. Even in this case, the electronic component can be positioned on the printed board stably and in a short time.

  In the electronic component mounting head according to the third aspect, the pressure-sensitive adhesive is a sealing agent. Even in this case, the electronic component can be positioned on the printed circuit board stably and in a short time.

  In the electronic component mounting method according to claim 4, in the contact detection step, the contact between the adhesive and the electronic component or the printed board is detected by the piezoelectric element, and in the vibration applying step, the piezoelectric element is perpendicular to the printed circuit board. Since the adhesive is removed from the joint between the electronic component and the printed circuit board by applying a vibration to the electronic component, the adhesive can be removed from the joint between the electronic component and the printed circuit board. It is possible to prevent the part from shifting. Therefore, according to this electronic component mounting method, the electronic component can be positioned on the printed board stably and in a short time.

  Embodiments 1 and 2 embodying an electronic component mounting head and an electronic component mounting method according to the present invention will be described below with reference to the drawings. As shown in FIG. 1, the electronic component mounting head according to the first embodiment includes a suction nozzle 10, a housing 20, a head body 30, and a piezo element 31. In the electronic component mounting head, the head body 30 is held by a lifting device (not shown) so as to be lifted and lowered.

  The suction nozzle 10 sucks the bare chip 1 on which the bumps 2 are formed at the tip portion 11a and mounts it on the printed circuit board 5. The suction nozzle 10 includes the suction tube 11, the back plate 12, the piston rod portion 13, and the piston portion 14. is doing. Here, the bare chip 1 is an electronic component. The adsorption tube 11 has a cylindrical shape, and the bare chip 1 can be adsorbed by the distal end portion 11a. The back plate 12 has a disk shape, and is provided at the upper end of the adsorption tube 11 so as to be coaxial with the adsorption tube 11. The back plate 12 serves to illuminate the bare chip 1 that is reflected on the adsorption tube 11 by reflecting light and to form a background of the bare chip 1. The adsorption pipe 11 and the back plate 12 may be removable from the piston rod portion 13.

  The piston rod portion 13 has a rectangular cross-sectional shape and is provided integrally with the upper end of the back plate 12. The piston portion 14 also has a rectangular cross-sectional shape, and is provided integrally with the upper end of the piston rod portion 13. However, the cross-sectional shape of the piston portion 14 is larger than the cross-sectional shape of the piston rod portion 13. At the upper end of the piston portion 14, a flange portion 14a protruding outward is formed. Further, a negative pressure passage 15 is provided through the piston portion 14, the piston rod portion 13, the back plate 12 and the central portion of the adsorption pipe 11 from the side surface of the piston portion 14. By making the negative pressure passage 15 have a negative pressure, the bare chip 1 can be adsorbed by the tip portion 11 a of the adsorption tube 11.

  The housing 20 has a rectangular parallelepiped shape, and its upper end is fixed to the head body 30. Further, the housing 20 is provided with a first chamber 21, a second chamber 22, a third chamber 23, and a fourth chamber 24 that are rectangular in cross section from the upper end to the lower end. The first chamber 21 has an opening at the upper end of the housing 20, and the fourth chamber 24 has an opening at the lower end of the housing 20.

  A piezo element 31 having a rectangular parallelepiped shape is slidably inserted into the first chamber 21, and a part of the piezo element 31 is inserted into the second chamber 22. Further, the upper end of the piezo element 31 is fixed to the head main body 30, and the lower end thereof can be brought into contact with the flange portion 14 a of the piston portion 14. Further, the piezo element 31 is electrically connected to a switching circuit 36 that switches between the input circuit 37 and the output circuit 38. When the piezo element 31 is connected to the input circuit 37 by the switching circuit 36, the piezo element 31 comes into contact with the cream solder 7 as a viscous agent applied to the electrode pad 6 of the printed circuit board 5 and the bump 2 of the bare chip 1. It serves as a sensor that detects When the piezo element 31 is connected to the output circuit 38 by the switching circuit 36, the piezo element 31 applies a vertical vibration, which is a vibration perpendicular to the printed circuit board 5, to the bare chip 1, and the bump 2 and the print of the bare chip 1. It plays the role of an actuator that removes the cream solder 7 from the joint between the substrate 5 and the electrode pad 6. The cream solder 7 is mixed with flux.

  In the second chamber 22, the flange portion 14 a of the piston portion 14 is slidably accommodated, and a gas supply path 22 a connected to the pressure control device 33 is opened through the side wall of the housing 20. In the third chamber 23, the piston portion 14 is slidably housed, and a gas supply path 23a connected to the bearing gas supply apparatus 34, a negative pressure supply path 23b connected to the negative pressure supply apparatus 35, A gas supply path 23 c connected to the pressure control device 33 opens through the side wall of the housing 20. In addition, a hydrostatic bearing 32 made of four porous materials is disposed on the inner peripheral surface of the third chamber 23 so as to surround the piston portion 14. A piston rod portion 13 is slidably provided in the fourth chamber 24, and a hydrostatic bearing 32 made of four porous materials surrounds the piston rod portion 13 on the inner peripheral surface of the fourth chamber 24. It is arranged. When air is supplied to the gas supply path 23 a from the bearing gas supply device 34, the piston rod portion 13 and the piston portion 14 are moved from the inner peripheral surfaces of the third chamber 23 and the fourth chamber 24 by the action of the static pressure bearing 32. Supported without contact. Further, the negative pressure supply path 23 b communicates with the negative pressure path 15, and when the negative pressure supply path 23 b is made negative by the negative pressure supply device 35, the bare chip 1 is adsorbed by the tip portion 11 a of the adsorption pipe 11. be able to. Further, when air is supplied from the pressure control device 33 to the gas supply path 22a, the flange portion 14a is pressed downward, and the suction nozzle 10 is lowered. Further, when air is supplied from the pressure control device 33 to the gas supply path 23c, the piston portion 14 is pressed upward, and the suction nozzle 10 is raised.

  Next, an electronic component mounting method using the electronic component mounting head will be described with reference to FIG. When mounting of the bare chip 1 to the printed circuit board 5 is instructed by a control device (not shown), cream solder 7 is applied to the electrode pads 6 of the printed circuit board 5 by printing in step S1. Then, the printed circuit board 5 is clamped at a predetermined position. In parallel with this, the bare chip 1 is sucked by the suction nozzle 10 and moved to the mounting position above the printed circuit board 5. Thus, the state shown in FIG. 1 is obtained. Then, the switching circuit 36 is switched to the input circuit 37, the piezo element 31 is connected to the input circuit 37, and air is supplied from the bearing gas supply device 34 and the pressure control device 33 to the gas supply passages 23a and 23c. . As a result, the piston rod portion 13 and the piston portion 14 are supported without contacting the inner peripheral surfaces of the third chamber 23 and the fourth chamber 24, and the suction nozzle 10 is pushed upward, as shown in FIG. The pressure P0 is applied to the piezo element 31 (the pressure P0 is detected by the piezo element 31). Here, FIG. 5 shows the relationship between the time t and the pressure P detected by the piezo element 31. Thus, pushing up the suction nozzle 10 upward and applying the pressure P0 to the piezo element 31 eliminates backlash between the suction nozzle 10 and the piezo element 31 and causes vibration due to backlash during the lowering operation of the suction nozzle 10. This is to suppress disturbance. Thereby, the adsorption | suction attitude | position of the bare chip 1 can be stabilized, a fall can be prevented, and the detection accuracy as a sensor of the piezo element 31 can be improved. Step S1 is an adhesive application process.

  In step S2, the electronic component mounting head is lowered by a motor (not shown), and the suction nozzle 10 is lowered as shown in FIG. As shown in FIG. 4, the lowering speed V of the suction nozzle 10 is gradually increased until time t1, and the lowering speed V of the suction nozzle 10 is gradually decreased from time t1 to time t2. Here, FIG. 4 shows the relationship between the time t and the elevation speed V of the electronic component mounting head. Times t1 and t2 are calculated based on the data calculated from the shape and the like of the bare chip 1 by the control device, and the electronic component mounting head is controlled by the motor at the times t1 and t2. Step S2 is a suction nozzle lowering step.

  In step S3, contact between the cream solder 7 applied to the electrode pads 6 of the printed circuit board 5 and the bumps 2 of the bare chip 1 is detected. If the pressure P input from the piezo element 31 to the input circuit 37 is greater than or equal to the threshold (YES), it is determined that the cream solder 7 and the bump 2 are in contact with each other as shown in FIG. Proceed to S4. If the pressure P input from the piezo element 31 to the input circuit 37 is smaller than the threshold value (NO), step S3 is repeatedly executed. As shown in FIG. 5, the pressure P1 is detected by the piezo element 31 at time t2, thereby detecting that the cream solder 7 and the bump 2 are in contact with each other. As shown in FIG. 4, the lowering speed V of the suction nozzle 10 is made constant from time t2. Step S3 is a contact detection step.

  In step S <b> 4, longitudinal vibration that is perpendicular to the printed circuit board 5 is given to the bare chip 1. That is, the switching circuit 36 is switched to the output circuit 38, and the piezo element 31 is connected to the output circuit 38. As a result, as shown in FIG. 6, pressure P2 is applied from the piezo element 31 to the suction nozzle 10 at a predetermined period from time t3, and longitudinal vibration is applied to the bare chip 1. Thus, as shown in FIG. 3C, the cream solder 7 is removed from the joint portion between the bump 2 of the bare chip 1 and the electrode pad 6 of the printed circuit board 5. Here, FIG. 6 shows the relationship between the time t and the pressure P applied from the piezo element 31 to the suction nozzle 10. This step S4 is a vibration applying process.

  In step S5, the process waits until the electrode pad 6 of the printed circuit board 5 and the bump 2 of the bare chip 1 come into contact with each other. After the electrode pad 6 of the printed circuit board 5 and the bump 2 of the bare chip 1 are in contact (YES), the process proceeds to step S6. However, the contact between the electrode pad 6 of the printed circuit board 5 and the bump 2 of the bare chip 1 is determined based on the data calculated from the shape of the bare chip 1 by the control device. That is, the time t4 is calculated based on the data calculated from the shape and the like of the bare chip 1 by the control device, and when the time t4 is reached, the electrode pad 6 of the printed circuit board 5 and the bump 2 of the bare chip 1 contact each other. To be judged.

  In step S6, a positioning process between the printed circuit board 5 and the bare chip 1 is performed. As shown in FIG. 4, the motor is stopped at time t4, and the lowering of the electronic component mounting head is stopped. Further, as shown in FIG. 6, the pressure P2 applied to the piezo element 31 at a predetermined period at time t4 is stopped, and the longitudinal vibration applied to the bare chip 1 is stopped. Further, as shown in FIG. 7, during the period from time t4 to time t5, the air supply from the pressure control device 33 to the gas supply path 23c is stopped and the air is supplied to the gas supply path 22a. A load F is applied. Thereby, the load F is applied to the bare chip 1 and the bare chip 1 is pressed against the printed circuit board 5, so that the printed circuit board 5 and the bare chip 1 are reliably positioned. However, instead of supplying air from the pressure control device 33 to the gas supply path 22a, the load F may be applied to the suction nozzle 10 by driving the air cylinder connected to the head body 30 and pushing down the electronic component mounting head. Good. Also, as shown in FIG. 4, the electronic component mounting head is raised by the motor from time t5, and the clamp of the printed circuit board 5 is released and discharged from a predetermined position. Times t4 and t5 are calculated based on data calculated from the shape of the bare chip 1 by the control device. Here, FIG. 7 is a diagram illustrating the relationship between the time t and the load F applied to the suction nozzle 10.

  In step S <b> 7, the cream solder 7 is melted and solidified to bond the bumps 2 of the bare chip 1 and the electrode pads 6 of the printed circuit board 5. Step S7 is a joining process.

  In the electronic component mounting head and the electronic component mounting method of the first embodiment, the contact between the cream solder 7 applied to the printed circuit board 5 and the bare chip 1 is detected between the suction nozzle 10 and the head body 30. A piezoelectric element 31 is provided that applies a vibration perpendicular to the printed circuit board 5 to the bare chip 1 to eliminate the cream solder 7 from the joint between the bare chip 1 and the printed circuit board 5. Then, in the contact detection step S3, the contact between the cream solder 7 and the bare chip 1 is detected by the piezo element 31, and in the vibration applying step S4, vibration perpendicular to the printed circuit board 5 is applied to the bare chip 1 by the piezo element 31. Thus, the cream solder 7 is excluded from the joint between the bare chip 1 and the printed circuit board 5. Therefore, the cream solder 7 can be eliminated from the joint between the bare chip 1 and the printed circuit board 5, and the joint between the bare chip 1 and the printed circuit board 5 can be prevented from shifting. Therefore, according to this electronic component mounting head, it is possible to position the bare chip 1 on the printed circuit board 5 stably and in a short time.

  As shown in FIG. 8, the electronic component mounting head of Embodiment 2 includes a suction nozzle 10, a housing 40, a head body 30, and a piezo element 31. However, the same reference numerals are used for the same components as those of the electronic component mounting head of Embodiment 1 shown in FIG. 1, and the description thereof is omitted.

  The housing 40 has a rectangular parallelepiped shape, and its upper end is fixed to the head body 30. Further, the housing 40 is provided with a first chamber 41, a second chamber 42, a third chamber 43, and a fourth chamber 44 having a rectangular cross-sectional shape from the upper end to the lower end. The first chamber 41 has an opening at the upper end of the housing 40, and the fourth chamber 44 has an opening at the lower end of the housing 40.

  A piezo element 31 having a rectangular parallelepiped shape is slidably penetrated in the first chamber 41, and a part of the piezo element 31 penetrates into the second chamber 42. Further, the upper end of the piezo element 31 is fixed to the head body 30, and the lower end is fixed to the flange portion 14 a of the piston portion 14. Further, the piezo element 31 is electrically connected to a switching circuit 36 that switches between the input circuit 37 and the output circuit 38. When the piezo element 31 is connected to the input circuit 37 by the switching circuit 36, the piezo element 31 causes the sealant 8 as a viscous agent applied between the electrode pads 6 of the printed circuit board 5 to contact the bare chip 1. Serves as a sensor to detect. When the piezo element 31 is connected to the output circuit 38 by the switching circuit 36, the piezo element 31 applies a vertical vibration, which is a vibration perpendicular to the printed circuit board 5, to the bare chip 1, and the bump 2 and the print of the bare chip 1. It plays the role of an actuator that excludes the sealant 8 from the joint between the substrate 5 and the electrode pad 6.

  In the second chamber 42, the flange portion 14a of the piston portion 14 is slidably accommodated. In the third chamber 43, the piston portion 14 is slidably accommodated, and a gas supply path 43a connected to the bearing gas supply apparatus 34 and a negative pressure supply path 43b connected to the negative pressure supply apparatus 35 are provided. An opening is made through the side wall of the housing 40. A hydrostatic bearing 32 made of four porous materials is disposed on the inner circumferential surface of the third chamber 43 so as to surround the piston portion 14. A piston rod portion 13 is slidably provided in the fourth chamber 44, and a hydrostatic bearing 32 made of four porous materials surrounds the piston rod portion 13 on the inner peripheral surface of the fourth chamber 44. It is arranged. When air is supplied to the gas supply path 43 a from the bearing gas supply device 34, the piston rod portion 13 and the piston portion 14 are connected to the inner peripheral surfaces of the third chamber 43 and the fourth chamber 44 by the action of the static pressure bearing 32. Supported without contact. Further, the negative pressure supply path 23 b communicates with the negative pressure path 15, and when the negative pressure supply path 43 b is made negative by the negative pressure supply device 35, the bare chip 1 is adsorbed by the distal end portion 11 a of the adsorption pipe 11. be able to.

  Next, an electronic component mounting method using the electronic component mounting head will be described with reference to FIG. When mounting of the bare chip 1 to the printed circuit board 5 is instructed by a control device (not shown), the sealant 8 is applied between the electrode pads 6 of the printed circuit board 5 in step S11. Then, the printed circuit board 5 is clamped at a predetermined position. In parallel with this, the bare chip 1 is sucked by the suction nozzle 10 and moved to the mounting position above the printed circuit board 5. Thus, the state shown in FIG. 8 is obtained. Then, the switching circuit 36 is switched to the input circuit 37, the piezo element 31 is connected to the input circuit 37, and air is supplied from the bearing gas supply device 34 to the gas supply path 43a. Thereby, the piston rod part 13 and the piston part 14 are supported without contacting the inner peripheral surfaces of the third chamber 43 and the fourth chamber 44. Step S11 is an adhesive application process.

  In step S12, the electronic component mounting head is lowered by a motor (not shown), and the suction nozzle 10 is lowered as shown in FIGS. 10 (A) and 10 (B). 10A is a front view, and FIG. 10B is a side view. As shown in FIG. 11, the lowering speed V of the suction nozzle 10 is gradually increased until time t1, and the lowering speed V of the suction nozzle 10 is gradually decreased from time t1 to time t2. Here, FIG. 11 shows the relationship between the time t and the elevation speed V of the electronic component mounting head. Times t1 and t2 are calculated based on the data calculated from the shape and the like of the bare chip 1 by the control device, and the electronic component mounting head is controlled by the motor at the times t1 and t2. Step S12 is a suction nozzle lowering step.

  In step S13, contact between the sealant 8 applied between the electrode pads 6 of the printed circuit board 5 and the bare chip 1 is detected. If the pressure P input from the piezo element 31 to the input circuit 37 is equal to or higher than the threshold value (YES), it is determined that the sealant 8 and the bare chip 1 are in contact, and the process proceeds to step S14. If the pressure P input from the piezo element 31 to the input circuit 37 is smaller than the threshold value (NO), step S13 is repeatedly executed. As shown in FIG. 12, the pressure P3 is detected by the piezo element 31 at time t2, and it is detected that the sealant 8 and the bare chip 1 are in contact with each other. Here, FIG. 12 shows the relationship between the time t and the pressure P detected by the piezo element 31. In addition, as shown in FIG. 11, the descending speed V of the suction nozzle 10 is made constant from time t2. Step S13 is a contact detection step.

  In step S <b> 14, longitudinal vibration which is vibration perpendicular to the printed circuit board 5 is given to the bare chip 1. That is, the switching circuit 36 is switched to the output circuit 38, and the piezo element 31 is connected to the output circuit 38. As a result, as shown in FIG. 13, the pressure P4 is applied from the piezo element 31 to the suction nozzle 10 at a predetermined cycle from time t3, and vertical vibration is applied to the bare chip 1. Thus, as shown in FIG. 10C, the sealant 8 is removed from the joint portion between the bump 2 of the bare chip 1 and the electrode pad 6 of the printed circuit board 5. Here, FIG. 13 shows the relationship between the time t and the pressure P applied from the piezo element 31 to the suction nozzle 10. This step S14 is a vibration applying step.

  In step S15, the process waits until the electrode pad 6 of the printed circuit board 5 contacts the bump 2 of the bare chip 1. After the electrode pad 6 of the printed circuit board 5 and the bump 2 of the bare chip 1 are in contact (YES), the process proceeds to step S16. However, the contact between the electrode pad 6 of the printed circuit board 5 and the bump 2 of the bare chip 1 is determined based on the data calculated from the shape of the bare chip 1 by the control device. That is, the time t4 is calculated based on the data calculated from the shape and the like of the bare chip 1 by the control device, and when the time t4 is reached, the electrode pad 6 of the printed circuit board 5 and the bump 2 of the bare chip 1 contact each other. To be judged.

  In step S16, as shown in FIG. 11, the motor is stopped at time t4, and the lowering of the electronic component mounting head is stopped. Further, as shown in FIG. 13, the pressure P4 applied from the piezo element 31 to the suction nozzle 10 at a predetermined period at time t4 is stopped, and the pressure P5 is applied from the piezo element 31 to the suction nozzle 10. Then, a lateral ultrasonic vibration that is a vibration parallel to the printed circuit board 5 is applied to the suction nozzle 10 by a horn and a vibrator (not shown) connected to the head body 30. Thereby, the ultrasonic vibration of a horizontal direction is provided to the bare chip 1 in the state pressed to the electrode pad 6 by the pressure P4 to the vertical direction. Thus, the ultrasonic vibration energy causes the bonding portion between the bump 2 of the bare chip 1 and the electrode pad 6 of the printed circuit board 5 to be melt bonded, and the bare chip 1 is bonded to the printed circuit board 5. Then, the electronic component mounting head is raised, and the clamp of the printed circuit board 5 is released and discharged from a predetermined position.

  In the electronic component mounting head and the electronic component mounting method according to the second embodiment, contact between the suction nozzle 10 and the head body 30 between the sealant 8 applied to the printed circuit board 5 and the bare chip 1 is detected. In addition, a piezoelectric element 31 is provided that applies vibration perpendicular to the printed circuit board 5 to the bare chip 1 to remove the sealant 8 from the joint between the bare chip 1 and the printed circuit board 5. Then, in the contact detection step S13, the contact between the sealant 8 and the bare chip 1 is detected by the piezo element 31, and in the vibration applying step S14, vibration perpendicular to the printed circuit board 5 is applied to the bare chip 1 by the piezo element 31. The sealant 8 is excluded from the joint between the bare chip 1 and the printed board 5. Therefore, the sealant 8 can be eliminated from the joint portion between the bare chip 1 and the printed board 5, and the joint portion between the bare chip 1 and the printed board 5 can be prevented from shifting. Therefore, according to this electronic component mounting head, it is possible to position the bare chip 1 on the printed circuit board 5 stably and in a short time.

  The electronic component mounting head and the electronic component mounting method according to the present invention have been described above with reference to the first and second embodiments. However, the present invention is not limited to these and is not contrary to the technical idea of the present invention. Needless to say, the present invention can be appropriately changed and applied.

FIG. 3 is a cross-sectional view of the electronic component suction head according to the first embodiment. 5 is a flowchart of an electronic component mounting method according to the first embodiment. The figure which concerns on Embodiment 1 and shows the relationship between a bare chip and a printed circuit board. The figure which concerns on Embodiment 1 and shows the relationship between time and the raising / lowering speed of an electronic component mounting head. The figure which concerns on Embodiment 1 and shows the relationship between time and the pressure which a piezo element detects. The figure which concerns on Embodiment 1 and shows the relationship between the time and the pressure applied to a suction nozzle by a piezo element. The figure which concerns on Embodiment 1 and shows the relationship between the time and the load added to a suction nozzle. FIG. 6 is a cross-sectional view of an electronic component suction head according to the second embodiment. 10 is a flowchart of an electronic component mounting method according to the second embodiment. The figure which concerns on Embodiment 2 and shows the relationship between a bare chip and a printed circuit board. The figure which concerns on Embodiment 2 and shows the relationship between time and the raising / lowering speed of an electronic component mounting head. The figure which concerns on Embodiment 2 and shows the relationship between time and the pressure which a piezo element detects. The figure which concerns on Embodiment 2 and shows the relationship between the time and the pressure applied to a suction nozzle by a piezo element.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electronic component (bare chip), 5 ... Printed circuit board, 7, 8 ... Adhesive (7 ... Cream solder, 8 ... Sealing agent) 10 ... Adsorption nozzle, 30 ... Head main body, 31 ... Piezo element, S1, S11 ... adhesive application process, S2, S12 ... adsorption nozzle lowering process, S3, S13 ... contact detection process, S4, S14 ... vibration applying process, S7, S16 ... joining process.

Claims (4)

In an electronic component mounting head comprising: a suction nozzle that sucks an electronic component at a tip portion and mounts the electronic component on a printed circuit board; and a head body that can move the suction nozzle perpendicular to the printed circuit board.
A piezo element having an upper end fixed to the head body and a lower end slidably mounted on the head body and capable of contacting the suction nozzle;
When the suction nozzle that sucks the electronic component at the tip is moved perpendicularly to the printed circuit board by the head body, the adhesive applied to the printed circuit board or / and the electronic component and the electronic component or the print An input circuit connected to the piezo element in order to cause the piezo element to play a role as a sensor for detecting contact with a substrate;
When contact between the pressure-sensitive adhesive and the electronic component or the printed board is detected, the electronic component and the printed board are vibrated by vibrating the piezoelectric element perpendicularly to the printed board and vibrating the suction nozzle. An output circuit connected to the piezo element in order to cause the piezo element to play a role as an actuator for removing the adhesive from the joint portion of
An electronic component mounting head comprising: 2. The electronic component mounting head according to claim 1, wherein the adhesive is cream solder. 2. The electronic component mounting head according to claim 1, wherein the adhesive is a sealant.

In an electronic component mounting method for mounting an electronic component on a printed circuit board,
An adhesive application step of applying an adhesive to the printed circuit board or / and the electronic component;
A suction nozzle lowering step of moving the suction nozzle that sucks the electronic component at the tip portion perpendicularly to the printed circuit board;
A contact detection step of detecting contact between the adhesive and the electronic component or the printed circuit board by a piezo element;
A vibration applying step of applying vibration perpendicular to the printed circuit board to the electronic component by the piezoelectric element to exclude the adhesive from a joint portion between the electronic component and the printed circuit board;
A bonding step of bonding the electronic component to the printed circuit board.

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