JP2009277850A - Mounting device and mounting method for electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mounting device that shortens the cycle time of a semiconductor chip and improves the mounting precision. <P>SOLUTION: The mounting device includes a first support body 8 which supports a mounting tool 11 sucking the semiconductor chip 2 atop so that it is displaced in vertical directions, a spring 13 elastically holding the mounting tool on the first support body, a pressure application tool 29 which is provided above the mounting tool to drive the mounting tool in the vertical directions, and mounts the semiconductor chip sucked to a suction portion on a substrate by pressing and lowering the mounting tool against the holding force of the spring when driven in the downward direction, a height adjustment driving source 18 which sets a height position of the mounting tool, and a driving source 32 for pressure application which detects the height of the mounting tool when a height of the mounting tool is set by the height adjustment driving source so that a reverse surface of the semiconductor chip is at a predetermined height, and then positions the pressure application tool based upon the detection result so that the interval between the mounting tool and pressure application tool becomes 0. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic component mounting apparatus and mounting method for mounting an electronic component on a substrate by pressing a mounting tool holding the electronic component on a lower end surface in a downward direction by a pressure member.

  In a mounting apparatus such as a flip chip method for mounting a semiconductor chip as an electronic component on a substrate, the semiconductor chip picked up by a pickup tool from the chip supply unit is received by the transfer tool, and the mounting tool of the mounting apparatus is received by the transfer tool. It is delivered to the suction part provided in

  The mounting tool that has received the semiconductor chip is positioned in the X and Y directions so as to be positioned above the mounting position of the substrate, and then driven in the downward direction by a pressing tool provided at the mounting position. As a result, the semiconductor chip sucked and held by the sucking portion is pressed and mounted on the substrate via a connecting member such as a paste-like adhesive, an anisotropic conductive member, or a solder bump.

  Before mounting the semiconductor chip on the substrate, a camera unit capable of simultaneously imaging both the upper and lower directions enters between the semiconductor chip conveyed to the mounting position by the mounting tool and the substrate positioned at the mounting position. The semiconductor chip and the substrate are imaged. Then, based on the imaging, the semiconductor chip and the substrate are precisely positioned in the X and Y directions, and then the semiconductor chip is mounted on the substrate.

  The camera unit includes two imaging optical systems, and the semiconductor chip and the substrate are respectively imaged by the imaging optical systems. Therefore, unless the semiconductor chip and the substrate are positioned at the focal position of the imaging optical system of the camera unit, it may be impossible to reliably recognize the positions of the semiconductor chip and the substrate.

  Therefore, conventionally, the mounting tool is configured to be able to be positioned in the vertical direction, and the pressurizing body is disposed so that the lower end surface faces the upper end surface of the mounting tool at a predetermined interval. Then, when the semiconductor chip is changed to a different thickness, the height of the mounting tool is changed to image one (upper) of the semiconductor chip of the camera unit inserted between the semiconductor chip and the substrate. After positioning so that the lower end surface of the semiconductor chip coincides with the focal position of the imaging optical system, the semiconductor chip and the substrate are imaged, and the semiconductor chip is positioned with respect to the X and Y directions based on the imaging. It was done to implement.

The upper surface of the substrate is transported and positioned at a height that matches the focal position of the other (lower) imaging optical system.
A conventional mounting apparatus having such a configuration is disclosed in Patent Document 1.
JP-A-5-206690

  By the way, in the mounting apparatus configured as described above, when the thickness of the semiconductor chip is changed, the positioning adjustment in the vertical direction of the mounting tool can be performed with a margin according to the thickness. The interval between the upper end surface of the mounting tool and the lower end surface of the pressing body is set to be sufficiently large.

  Therefore, when the vertical position of the mounting tool is set so that the lower end surface of the semiconductor chip matches the focal position of the imaging optical system of the camera unit according to the change in the thickness of the semiconductor chip, There was a gap between the end face and the lower end face of the pressure member.

  Therefore, when the pressure body is driven in the downward direction to pressurize the mounting tool, the pressure body is further lowered by the gap between the upper end surface of the mounting tool and the lower end surface of the pressure body. Since it has to be, the stroke of the pressurizing body becomes longer by the gap, and the tact time required for mounting may become longer.

  In addition, the lower end surface of the pressurizing body collides with the upper end surface of the mounting tool from a non-contact state due to the lowering of the pressurizing body, and then pressurizes and presses down the mounting tool. For this reason, vibration is generated in the mounting tool due to an impact applied to the mounting tool at the time of collision, and there is a possibility that the mounting accuracy of the semiconductor chip may be reduced due to the vibration.

  In particular, when the lowering speed of the pressurizing body is increased in order to shorten the tact time, the impact generated on the mounting tool at the time of the collision increases, so that the accuracy of mounting the semiconductor chip may be significantly reduced.

  In this invention, the interval between the upper end surface of the mounting tool and the lower end surface of the pressing tool can be set to 0, so that the tact time during mounting can be shortened or the mounting tool vibrates during mounting. It is an object of the present invention to provide an electronic component mounting apparatus and mounting method capable of preventing a reduction in accuracy.

The present invention is a mounting apparatus for mounting an electronic component on a substrate,
A mounting tool in which a suction part for sucking the electronic component is formed at the tip;
Guide means for supporting the mounting tool so as to be vertically displaceable,
Elastic holding means for elastically holding the mounting tool on the guide means;
Above the mounting tool, provided so as to be able to be driven in the vertical direction, when driven in the downward direction, the mounting tool is pressed against the holding force of the elastic holding means to be lowered and sucked to the suction portion A pressure tool for mounting electronic components on the substrate;
A height setting means for setting a height position along the guide means of the mounting tool against a holding force by the elastic holding means;
The height of the mounting tool is detected when the height setting means sets the height of the mounting tool so that the lower surface of the electronic component sucked by the suction portion of the mounting tool has a predetermined height. An electronic component mounting apparatus comprising: positioning means for positioning the pressurizing tool so that a distance between the mounting tool and the pressurizing tool becomes zero based on detection.

  Drive means for driving the pressurizing tool in the vertical direction is provided, and the positioning means drives the drive means based on detection of the detecting means to contact the lower end surface of the pressurizing body with the upper end surface of the mounting tool. It is preferable to make it.

  An imaging means for simultaneously imaging both of the electronic component sucked by the suction portion of the mounting tool and the substrate is inserted, and the height of the lower surface of the electronic component is based on the focal length of the imaging means. It is preferable that the predetermined height is set.

This invention is a mounting method of mounting the electronic component on a substrate by pressing a mounting tool having an electronic component adsorbed and held at the tip in a downward direction by a pressing tool,
Detecting the height of the mounting tool as a first height when the mounting tool is raised and its upper end surface is brought into contact with the lower end surface of the pressing tool;
Detecting the height of the mounting tool as a second height when the mounting tool is lowered and the lower surface of the electronic component is positioned at a predetermined height;
The distance between the upper end surface of the mounting tool and the lower end surface of the pressing tool set to the second height from the first height and the second height is obtained, and the distance is set to 0 so that the distance becomes zero. And a step of lowering the pressure tool.

  According to the present invention, the height of the mounting tool when the upper end surface of the mounting tool is brought into contact with the lower end surface of the pressing tool, and the lower end surface of the electronic component held by the mounting tool are set to a predetermined height. The height of the mounting tool at the time of positioning can be detected, and the electronic component can be mounted by setting the interval between the upper end surface of the mounting tool and the lower end surface of the pressing tool to 0 based on these detections. For this reason, it is possible to shorten the tact time and prevent the vibration of the mounting tool during mounting.

  An embodiment of the present invention will be described below with reference to the drawings.

  The mounting apparatus shown in FIG. 1 includes a pair of guide rails 1 arranged in parallel and spaced apart from each other, which constitute a conveying means. A substrate W such as a lead frame conveyed along the guide rail 1 is positioned at the mounting position B. For example, a semiconductor chip 2 as an electronic component is mounted on the substrate W positioned at the mounting position B.

  At the mounting position B, mounting means 5 is provided above the guide rail 1. A pressurizing means 6 is disposed above the mounting means 5 to operate the mounting means 5 as will be described later. The mounting means 5 has a first support 8. The first support 8 is driven by the X / Y drive source 7 in the X / Y direction which is the horizontal direction. The drive of the X / Y drive source 7 is controlled by a control device 21 (shown in FIG. 3) described later in FIG.

  A pair of linear guides 9 (only one is shown) is provided on one side surface of the first support 8 along the vertical direction, and a receiving portion 10 provided on the mounting tool 11 is movable on the linear guide 9. It is supported by. The lower end portion of the mounting tool 11 is formed on the suction portion 11a that sucks and holds the semiconductor chip 2 having the thickness t1 at the lower end surface.

  An inverted L-shaped hook member 12 is provided at the upper end of the first support 8. A spring 13 that elastically holds the mounting tool 11 is stretched between the hook member 12 and the middle part of the mounting tool 11 in the vertical direction.

  As shown in FIG. 2, a first attachment member 14 is provided on the upper end portion of the first support 8. The first mounting member 14 is provided with a height adjusting drive source 18 such as a pulse motor. A drive screw 15 is connected to the rotary shaft 18 a of the height adjusting drive source 18. The drive screw 15 is screwed into a pressing body 17 having a lower end surface formed on a convex curved surface 17a. The pressing body 17 can be moved in the vertical direction by means such as a key and a key groove (not shown) and is rotated on a second mounting member 19 projecting horizontally on the plate surface of the first support 8. It is held in an impossible state.

  The height adjusting drive source 18 is controlled by the control device 21 shown in FIG. When the height adjusting drive source 18 is activated and the drive screw 15 is rotationally driven, the rotation of the pressing body 17 is displaced in the vertical direction. When the pressing body 17 is driven in the downward direction, the mounting tool 11 is lowered against the restoring force of the spring 13, and when driven in the upward direction, the mounting tool 11 is raised by the restoring force of the spring 13. It has become.

  That is, when the drive screw 15 is rotated by the height adjusting drive source 18, the spring 13 is stretched against the restoring force or contracted by the restoring force according to the rotation direction. It can be elastically displaced along the linear guide 9 provided on one support body 8 in the ascending direction or the descending direction, and can be positioned at a predetermined height position.

  A shaft portion 11b is provided at the upper end portion of the mounting tool 11, and a radial bearing 24 partially extends upward from the upper end surface of the shaft portion 11b by a support shaft 23 whose axis is horizontal. It is installed to protrude.

  The pressurizing means 6 has a second support body 26 fixedly disposed above the mounting position B. The second support 26 is provided such that the plate surface is shifted by 90 degrees in the rotation direction about the vertical axis with respect to the first support 8, and the plate surface is spaced at a predetermined interval. A pair of spaced apart linear guides 27 are provided along the vertical direction.

  A movable body 28 is movably provided on the linear guide 27. An L-shaped pressurizing tool 29 is attached to the movable body 28 with its lower end projecting downward from the lower end of the movable body 28.

  The lower end surface of the pressurizing tool 29 is the upper end surface of the mounting tool 11 and serves as a pressurizing surface 29a that presses the upper end of the outer peripheral surface of the radial bearing 24 provided at the upper end of the shaft portion 11b as described later. Yes. The pressurizing surface 29a is formed with a larger area in the X and Y directions than the radial bearing 24.

  A holding member 31 is provided on the upper portion of the second support 26, and the holding member 31 has a pressurizing drive source 32 as a positioning means composed of, for example, a servo motor, the driving of which is controlled by the control device 21. It is provided with the axis vertical. The drive shaft 32 a of the pressurizing drive source 32 is connected to the movable body 28 via a joint 33.

  Therefore, when the pressurizing drive source 32 is operated and the drive shaft 32a is driven in the downward direction, the movable body 28 is lowered in conjunction with the drive shaft 32a. The upper end of the outer peripheral surface of the radial bearing 24 provided at the upper end of the shaft portion 11b of the mounting tool 11 is pressed by the pressing surface 29a of the pressure tool 29, and the pressing tool 29 is driven in the downward direction.

  The pressing tool 29 is positioned at the reference position by the pressing drive source 32. When the mounting tool 11 is similarly positioned at the reference position by the height adjustment drive source 18, it is between the pressing surface 29a of the pressing tool 29 and the radial bearing 24 provided at the upper end of the shaft portion 11b of the mounting tool 11. A gap indicated by C in FIG. 1 is formed.

  The reference positions of the pressurizing tool 29 and the mounting tool 11 are states in which no drive signal is output from the control device 21 to the pressurizing drive source 32 and the height adjusting drive source 18, and these reference positions are, for example, added. Setting is possible by manually positioning the drive shaft 32a of the pressure drive source 32 and the pressing body 17 in the axial direction.

  Before mounting the semiconductor chip 2 on the substrate W, the semiconductor chip 2 is positioned with respect to the substrate W in the X and Y directions as follows. That is, between the semiconductor chip 2 sucked and held by the suction portion 11a of the mounting tool 11 positioned at the mounting position B and the substrate W transported along the guide rail 1 and positioned at the mounting position B. An imaging camera 35 is inserted as imaging means capable of simultaneously imaging both the upper and lower surfaces.

  The imaging camera 35 has a flat box-shaped casing 36 in which an upper imaging optical system that images the upper direction and a lower imaging optical system (both not shown) that images the lower direction are accommodated. Imaging windows 37a and 37b are formed on the upper and lower surfaces of the housing 36, respectively. The housing 36 is driven in the X, Y, and Z directions by an X, Y, and Z driving source 38. The driving of the X / Y / Z drive source 38 is controlled by the control device 21.

  Images captured by the upper imaging optical system and the lower imaging optical system of the imaging camera 35 are displayed on a monitor 39 (shown in FIG. 3) connected to the control device 21. The imaging camera 35 is positioned by the X / Y / Z drive source 38 in the Z direction where the focal position of the lower imaging optical system coincides with the upper surface of the substrate W transported on the guide rail 1.

  In a state where the mounting tool 11 and the pressure tool 29 are at the reference position, the imaging camera 35 is driven in the X and Y directions, and the semiconductor chip 2 is sucked and held by the substrate W and the suction portion 11a of the mounting tool 11. The alignment marks (not shown) provided on the upper surface of the substrate W and the lower surface of the semiconductor chip 2 are simultaneously imaged.

  As a result, the control device 21 calculates the relative displacement between the substrate W and the semiconductor chip 2 in the X and Y directions, and the mounting tool 11 drives the X and Y based on the calculated X and Y coordinates. Driven in the X and Y directions by the source 7, the semiconductor chip 2 is positioned at the mounting position of the substrate W.

  The captured image of the lower surface of the semiconductor chip 2 is observed by the monitor 39. Then, the mounting tool 11 is driven in the upward or downward direction by the height adjustment drive source 18 so that the height position of the semiconductor chip 2 matches the focal position of the upper imaging optical system of the imaging camera 35 by the observation. The height is set as described later.

Next, an operation when the semiconductor chip 2 is mounted on the substrate W by the mounting apparatus having the above configuration will be described with reference to FIGS.
First, as shown in FIG. 4A, the mounting tool 11 is driven in the upward direction from the reference position by the height adjustment drive source 18, and the outer peripheral surface located at the upper end of the radial bearing 24, which is the upper end surface thereof, is added. The pressure tool 29 is brought into contact with the pressure surface 29a, which is the lower end surface, and the height of the mounting tool 11 at that time is detected as the first height H1. H1 is a distance from the upper surface of the substrate W positioned at the mounting position B to the lower end surface of the suction portion 11a of the mounting tool 11.

  Contact between the radial bearing 24 of the mounting tool 11 and the pressing surface 29a of the pressing tool 29 can be detected visually or by a touch sensor (not shown), and when the pressing tool 29 is set to the first height H1. The output signal from the height adjustment drive source 18 is output to the control device 21 and stored.

  Next, as shown in FIG. 4B, the imaging camera 35 is placed between the substrate W positioned at the mounting position B and the semiconductor chip 2 having the thickness t1 held by suction on the suction portion 11a of the mounting tool 11. The lower imaging optical system of the imaging camera 35 is inserted so that the focal point of the lower imaging optical system coincides with the upper surface of the substrate W.

  If the imaging camera 35 is inserted between the substrate W and the semiconductor chip 2, while observing the monitor 39 so that the lower surface of the semiconductor chip 2 coincides with the focus height position of the upper imaging optical system of the imaging camera 35. The mounting tool 11 is driven in the downward direction from the first height H1 by the height adjustment drive source 18.

  When the image of the semiconductor chip 2 is projected on the monitor 39 in a focused state, the lowering of the mounting tool 11 is stopped at that position. The height from the upper surface of the substrate W at that time to the lower end surface of the suction portion 11a is defined as a second height H2. When the mounting tool 11 is set to the second height H2, an output signal from the height adjustment drive source 18 is output to the control device 21 and stored.

  Next, the control device 21 calculates the relative shift amounts in the X and Y directions from the captured images of the substrate W and the lower surface of the semiconductor chip 2 by the imaging camera 35, and X and Y driving based on the calculation. The source 7 is driven to position the semiconductor chip 2 with respect to the substrate W.

  When the positioning of the semiconductor chip 2 with respect to the substrate W is completed, the control device 21 determines the pressing surface 29a of the pressing tool 29 and the mounting tool 11 from the stored first height H1 and second height H2. A distance C1 between the radial bearing 24 and the radial bearing 24 is calculated. That is, C1 is calculated by (H1-H2).

  When the distance C1 is calculated, the pressure driving is performed until the distance C1 is 0, that is, the position where the pressure surface 29a of the pressure tool 29 contacts the outer peripheral surface of the radial bearing 24 as shown in FIG. The source 32 is driven by the control device 21 to lower the pressing tool 29.

  The lowered position of the pressurizing tool 29 at this time is set in the control device 21 as the reference height position. That is, if the mounting tool 11 is positioned at the second height H2 when the thickness of the semiconductor chip 2 is t1, the lowering position of the pressing tool 29 is set to the reference height position. The pressing surface 29a and the outer peripheral surface of the radial bearing 24 provided at the upper end of the mounting tool 11 are in contact with each other without a gap.

  If the height position of the pressurizing tool 29 is set to the reference height position, the imaging camera 35 is retracted from between the substrate W and the semiconductor chip 2 and then the pressurizing drive source 32 is operated to pressurize. The tool 29 is lowered against the restoring force of the spring 13, and the semiconductor chip 2 sucked and held by the sucking portion 11 a is mounted on the substrate W. At this time, the lower surface of the substrate W is supported by a backup (not shown).

  The descending amount of the pressing tool 29 when the semiconductor chip 2 is mounted on the substrate W is set to (H2 + p). Here, p is a distance for generating pressure when the semiconductor chip 2 is mounted on the substrate W, and the distance is set according to various conditions.

  Thus, when the semiconductor chip 2 having the thickness t1 is mounted on the substrate W, the pressing surface 29a of the pressing tool 29 and the mounting tool are set by setting the height of the pressing tool 29 to the reference height position. The semiconductor chip 2 can be mounted on the substrate W by the pressurizing tool 29 in a state where the distance from the radial bearing 24 provided at 11 is zero.

  Therefore, the downward strokes of the pressing tool 29 and the mounting tool 11 when mounting the semiconductor chip 2 on the substrate W can be reduced, so that the tact time required for mounting can be shortened accordingly.

  Moreover, the pressing tool 29 presses and pushes down the mounting tool 11 in a state where the pressing surface 29a is in contact with the outer peripheral surface of the radial bearing 24 at the upper end of the mounting tool 11, so that the mounting tool 11 is not impacted. Can be lowered. As a result, the pressing tool 29 is lowered without generating vibration due to the impact, so that the mounting accuracy of the semiconductor chip 2 can be improved.

  When the thickness of the semiconductor chip 2 is changed from t1 to t2, the second height H2 and the interval C1 shown in FIG. 4B are calculated from the thickness difference Δt, that is, (t1−t2). can do. If the second height H2 and the interval C1 are obtained, the pressing surface 29a of the pressing tool 29 when the thickness of the semiconductor chip 2 is changed from t1 to t2 is the outer periphery of the radial bearing 24 at the upper end of the mounting tool 11. The reference height position of the pressure tool 29 that contacts the surface can be calculated.

  Therefore, even if the thickness of the semiconductor chip 2 is changed, the distance between the pressing surface 29a of the pressing tool 29 and the radial bearing 24 at the upper end of the mounting tool 11 is set to 0, and the suction portion 11a of the mounting tool 11 is placed. The semiconductor chip 2 held by suction can be mounted on the substrate W.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram of the mounting apparatus which shows one embodiment of this invention. The enlarged view to the part in which the height adjustment drive source which adjusts the height position of a mounting tool was provided. The block diagram of a control system. (A) Explanatory drawing of the state which raised the mounting tool and made the shape end surface contact the lower end surface of a pressurization tool, (b) made an imaging camera approach between a board | substrate and a mounting tool, and the focus of the camera An explanatory view when the lower surface of the semiconductor chip is made to coincide with the position, (c) is an explanatory view when the lower end surface of the pressing tool is brought into contact with the upper end surface when the height of the mounting tool is set.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 5 ... Mounting means, 6 ... Pressing means, 8 ... 1st support body (guide means), 9 ... Linear guide (guide means), 11 ... Mounting tool, 13 ... Spring (elastic holding means), 18 ... Height Adjustment drive source (height setting means), 21 ... control device, 29 ... pressurizing tool, 32 ... pressurization drive source (positioning means), 35 ... imaging camera (imaging means).

Claims (4)

A mounting device for mounting electronic components on a substrate,
A mounting tool in which a suction part for sucking the electronic component is formed at the tip;
Guide means for supporting the mounting tool so as to be vertically displaceable,
Elastic holding means for elastically holding the mounting tool on the guide means;
Above the mounting tool, provided so as to be able to be driven in the vertical direction, when driven in the downward direction, the mounting tool is pressed against the holding force of the elastic holding means to be lowered and sucked to the suction portion A pressure tool for mounting electronic components on the substrate;
A height setting means for setting a height position along the guide means of the mounting tool against a holding force by the elastic holding means;
The height of the mounting tool is detected when the height setting means sets the height of the mounting tool so that the lower surface of the electronic component sucked by the suction portion of the mounting tool has a predetermined height. An electronic component mounting apparatus comprising: positioning means for positioning the pressurizing tool so that a distance between the mounting tool and the pressurizing tool becomes zero based on detection.   Drive means for driving the pressurizing tool in the vertical direction is provided, and the positioning means drives the drive means based on detection of the detecting means to contact the lower end surface of the pressurizing body with the upper end surface of the mounting tool. The electronic component mounting apparatus according to claim 1, wherein:   An imaging means for simultaneously imaging both of the electronic component sucked by the suction portion of the mounting tool and the substrate is inserted, and the height of the lower surface of the electronic component is based on the focal length of the imaging means. 2. The electronic component mounting apparatus according to claim 1, wherein the height is set to the predetermined height. A mounting method of mounting the electronic component on a substrate by pressing a mounting tool having an electronic component adsorbed and held at the tip with a pressurizing tool in a downward direction,
Detecting the height of the mounting tool as a first height when the mounting tool is raised and its upper end surface is brought into contact with the lower end surface of the pressing tool;
Detecting the height of the mounting tool as a second height when the mounting tool is lowered and the lower surface of the electronic component is positioned at a predetermined height;
An interval between the upper end surface of the mounting tool and the lower end surface of the pressing tool set to the second height from the first height and the second height is obtained, and the interval is zero so that the interval is zero. A method for mounting an electronic component, comprising: a step of lowering a pressing tool.

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