JP2018098441A - Die bonder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a die bonder which bonds a device such as an LED, an IC, a LSI or the like with efficiency to a substrate.SOLUTION: A die bonder is constructed at least by: substrate holding means having a holding surface regulated in a X-axial direction and a Y-axial direction holding a substrate 10 on which a device is bonded while laminating an LED layer through a peering layer 30 onto an upper surface of an epitaxy substrate 241; wafer holding means of holding an external periphery of a wafer 24 distributed on the surface through the peeling layer by the plurality of devices; facing surface means of facing the surface of the wafer onto the upper surface of the substrate; device positioning means of positioning the device disposed to the wafer to a predetermined position of the substrate; and laser irradiation means of breaking the peeling layer 30 of the device by irradiating a laser light beam LB from a back surface of the wafer and bonding to the predetermined position of the substrate.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a die bonder for efficiently bonding a plurality of devices to a wiring board.

  An epitaxial layer consisting of a buffer layer, an N-type semiconductor layer, a light emitting layer, and a P-type semiconductor layer, and an N-type semiconductor layer and a P-type semiconductor layer are disposed on the upper surface of an epitaxial substrate such as a sapphire substrate or SiC substrate by epitaxial growth. In a wafer formed by dividing a plurality of LEDs composed of the electrodes and the planned division lines, the divided division lines are cut together with the epitaxy substrate by a laser beam or the like to be generated into individual LEDs. The individually divided red LED, green LED, and blue LED are assembled as a module by a die bonder bonded to a module chip (substrate) and used for, for example, a monitor (see, for example, Patent Document 1). .

  Devices such as IC and LSI are also selectively picked up by a collet from a wafer that is affixed to a dicing tape and divided into individual devices, and bonded to a wiring board by a die bonder.

JP-A-10-305420

  When assembling LEDs as modules by the above-described die bonder, it takes time and effort to bond the divided LEDs to the module chip one by one, and since LEDs have been downsized in recent years, there is a problem that productivity has deteriorated. .

  In addition, the dimensions of devices such as IC and LSI are gradually reduced in size, with one side being 100 μm or less and 50 μm or less, and the thickness is becoming as thin as 20 μm or less. There is a problem that it has become extremely difficult to selectively push up a device from a wafer thus picked up and pick it up by a collet and bond it to a wiring board.

  The present invention has been made in view of the above facts, and a main technical problem thereof is to provide a die bonder for efficiently bonding devices such as LEDs, ICs, LSIs, and the like, which are becoming smaller and thinner, to the substrate side. .

  In order to solve the above main technical problem, according to the present invention, a die bonder for bonding a device to a substrate has a holding surface defined in the X-axis direction and the Y-axis direction for holding the substrate to which the device is bonded. A substrate holding means, a wafer holding means for holding the outer periphery of a wafer having a plurality of devices disposed on the surface via a release layer, and the wafer holding means holding the surface of the wafer held by the substrate holding means Face-to-face means for facing the upper surface of the substrate, and device positioning means for moving the substrate holding means and the wafer holding means relative to each other in the X and Y directions to position a device disposed on the wafer at a predetermined position on the substrate Then, irradiate a laser beam from the backside of the wafer to destroy the peeling layer of the corresponding device and bond the device to a predetermined position on the substrate And Za irradiating means, at least configured die bonder is provided from the.

  The substrate is provided with an electrode facing the electrode of the device, and a bond layer is laid on the substrate side or the device side, and the device is mounted on the substrate by a shock wave of a laser beam irradiated corresponding to the device. Bonding at a position is preferable, and as the bonding material, a bonding material of an anisotropic conductor can be adopted.

  Two or more wafer holding means may be provided, and two or more types of devices may be selectively positioned on the substrate. The laser beam irradiation means includes a laser oscillator that oscillates a pulsed laser beam, and the laser. An fθ lens for condensing a laser beam oscillated by an oscillator onto a peeling layer of a wafer held by the wafer holding means; a positioning unit disposed between the laser oscillator and the fθ lens and positioning the laser beam on a corresponding device; , Can be made up of.

  The positioning unit includes an X direction AOD that deflects the laser beam oscillated by the laser oscillator in the X direction and a Y direction AOD that deflects the laser beam oscillated in the Y direction, or an X direction resonant that deflects the laser beam oscillated by the laser oscillator in the X direction. A Y direction resonant scanner that deflects in the Y direction, a X direction galvano scanner that deflects the laser beam generated by the laser oscillator in the X direction, and a Y direction galvano scanner that deflects in the Y direction. In addition, a polygon mirror may be further provided.

  In the die bonder of the present invention, a substrate holding means having a holding surface defined in the X-axis direction and the Y-axis direction for holding a substrate to which a device is bonded, and a plurality of devices are arranged on the surface via a release layer. Wafer holding means for holding the outer periphery of the wafer, facing means for causing the surface of the wafer held by the wafer holding means to face the upper surface of the substrate held by the substrate holding means, the substrate holding means and the wafer holding means, Is moved relative to the X direction and the Y direction to position the device disposed on the wafer at a predetermined position on the substrate, and a laser beam is irradiated from the back surface of the wafer to destroy the peeling layer of the corresponding device. And at least a laser irradiation means for bonding the device to a predetermined position on the substrate. It is possible to bond without the need to pick up the device selectively from the wafer and pick it up with a collet, making it possible to bond efficiently even if the size of the device is small, compared to the conventional die bonder, Productivity is greatly improved.

It is a whole perspective view of the die bonder comprised based on this invention, and a figure which expands and shows a LED board holding means. It is a block diagram for demonstrating the laser beam irradiation means with which the die bonder shown in FIG. 1 is mounted | worn. It is a figure which shows the module board | substrate with which the board | substrate with which a device is bonded in this embodiment is arrange | positioned. It is explanatory drawing for demonstrating the wafer by which the device in this embodiment was arrange | positioned through the peeling layer. It is explanatory drawing for demonstrating the effect | action of the wafer holding means to hold | maintain the LED wafer by which red LED of this embodiment was arrange | positioned. It is explanatory drawing for demonstrating the effect | action of the wafer holding means to hold | maintain the LED wafer by which green LED of this embodiment was arrange | positioned. It is explanatory drawing for demonstrating the effect | action of the wafer holding means to hold | maintain the LED wafer by which blue LED of this embodiment was arrange | positioned. In this embodiment, it is explanatory drawing for demonstrating the state in which a board | substrate holding means is positioned directly under a wafer holding means, and a laser beam is irradiated. It is explanatory drawing for demonstrating the process by which red LED is bonded in this embodiment. It is explanatory drawing for demonstrating the process in which green LED is bonded in this embodiment. It is explanatory drawing for demonstrating the process by which blue LED is bonded in this embodiment.

  Hereinafter, a preferred embodiment of a die bonder configured according to the present invention will be described in detail with reference to the accompanying drawings.

  The die bonder 40 in this embodiment is demonstrated referring FIG. The die bonder 40 shown in the figure includes a base 41, a substrate holding means 42 for holding a substrate to which a device is bonded, a moving means 43 for moving the substrate holding means 42, a laser beam irradiation means 44 for irradiating a laser beam, A frame 45 containing the laser beam irradiation means 44 extending upward from the upper surface of the table 41 and then extending substantially horizontally; and a control means constituted by a computer to be described later. It is configured to be controlled. Further, on the lower surface of the front end portion of the frame 45 extending horizontally, a condenser 44a including an fθ lens constituting the laser beam irradiation means 44, and a direction indicated by an arrow X in the figure with respect to the condenser 44a A wafer holding means 50 for holding a plurality of device wafers arranged adjacent to each other and an imaging means 48 for imaging a processing region of the workpiece are provided.

  The substrate holding means 42 has a rectangular X-direction movable plate 60 mounted on the base 41 so as to be movable in the X direction indicated by an arrow X in the drawing, and a X-movable X in the Y direction indicated by an arrow Y in the drawing. A rectangular Y-direction movable plate 61 mounted on the directional movable plate 60, a cylindrical column 62 fixed to the upper surface of the Y-direction movable plate 61, and a rectangular cover plate 63 fixed to the upper end of the column 62. Including. The cover plate 63 is provided with a holding table 64 for holding a circular workpiece that extends upward through a long hole formed on the cover plate 63. The workpiece is sucked and held by a suction chuck connected to a suction means (not shown) constituting the upper surface of the holding table 64. On the outer periphery of the holding table 64, a clamp 65 for holding and fixing a frame for holding a workpiece via an adhesive tape is disposed. In the present embodiment, the X direction is a direction indicated by an arrow X in FIG. 1, and the Y direction is a direction indicated by an arrow Y in FIG. 1 and is a direction orthogonal to the X direction. The plane defined by the X direction and the Y direction is substantially horizontal.

  The moving means 43 functioning as the device positioning means of the present invention includes an X direction moving means 80 and a Y direction moving means 82. The X direction moving means 80 converts the rotational motion of the motor into a linear motion and transmits it to the X direction movable plate 60, and moves the X direction movable plate 60 forward and backward along the guide rail on the base 41. The Y-direction moving means 82 converts the rotational motion of the motor into a linear motion, transmits it to the Y-direction movable plate 61, and advances and retracts the Y-direction movable plate 61 in the Y direction along the guide rail on the X-direction movable plate 60. . Although not shown, the X direction moving means 80 and the Y direction moving means 82 are respectively provided with position detecting means, and the holding table 64 is positioned in the X direction, the Y direction, and the circumferential direction. The rotational position is accurately detected, and the X-direction moving means 80 and the Y-direction moving means 82 are driven based on a signal instructed by the control means described later, so that the holding table can be accurately positioned at an arbitrary position and angle. It is possible.

  The image pickup means 48 includes an optical system and an image pickup device (CCD) constituting a microscope, and is configured to send a picked up image signal to the control means and display it on a display means (not shown). The control means is composed of a computer, and a central processing unit (CPU) that performs arithmetic processing according to the control program, a read only memory (ROM) that stores the control program, etc., and the detected detection values, arithmetic results, etc. are temporarily stored. A random access memory (RAM) that can be read and written, an input interface, and an output interface (details are omitted).

  Based on FIG. 2, the laser beam irradiation means 44 which irradiates a laser beam from the collector 44a is demonstrated. For example, as shown in FIG. 2A, the laser beam irradiation means 44 includes a laser oscillator 44b that oscillates the laser beam LB, an attenuator 44c that changes the transmittance of the laser beam LB oscillated from the laser oscillator 44b, and adjusts the output. The positioning unit 44d in the present embodiment is provided with a positioning unit 44d that functions to position the angle of the optical axis of the laser beam LB at a predetermined position of the holding table 64. The positioning unit 44d in this embodiment deflects the optical axis in the X direction ( (Hereinafter referred to as “X direction AOD”) 44d1 and an acoustooptic device (hereinafter referred to as “Y direction AOD”) 44d2 that deflects the optical axis in the Y direction with the same configuration as the X direction AOD44d1. And deflected by the action of the X direction AOD44d1 and the Y direction AOD44d2. A reflection mirror 44f for reflecting axis holding table 64 includes a condenser 44a for condensing the to the workpiece to be described later laser LB1~LB2 reflected by the reflecting mirror 44f.

  The condenser 44a includes an fθ lens 44g, and the irradiation position of the laser beam emitted from the condenser 44a is controlled in the range of LB1 to LB2 by the X direction AOD 44d1 and the Y direction AOD 44d2 constituting the positioning unit 44d described above. In addition, a desired position of the fθ lens 44g can be irradiated. By appropriately controlling the X direction AOD 44d1 and the Y direction AOD 44d2, the laser beams LB1 and LB2 are positioned and irradiated at desired positions of the wafers held by the wafer holding rings 52, 53, and 54 located immediately below the condenser 44a. The irradiation position can be controlled in the Y direction perpendicular to the paper surface illustrated in FIG. 2 and the X direction indicating the left-right direction of the paper surface. Note that the positioning unit 44d that irradiates the laser beam to a desired position of the fθ lens 44g is not limited to the above-described X direction AOD44d1 and Y direction AOD44d2, and any means that can deflect the laser beam irradiation direction. Other means such as an X direction resonant scanner, a Y direction resonant scanner, an X direction galvano scanner, a Y direction galvano scanner, and the like may be used. Further, the laser beam irradiation means 44 is not limited to the one having only the above-described configuration. For example, as shown in FIG. 2B, in addition to the X direction AOD 44d1 and the Y direction AOD 44d2, a polygon mirror 44h configured to rotate in the direction indicated by the arrow 44i may be provided. The polygon mirror 44h is driven by a polygon motor (not shown) in accordance with the frequency of the pulse laser beam oscillated from the laser oscillator 44b and is rotated at a high speed to change the irradiation direction of the laser beam LB at a high speed (44h indicated by a two-dot chain line). (See ´.) Thereby, a laser beam can be irradiated at high speed to a plurality of desired positions of the wafer held by the wafer holding rings 52, 53, and 54.

  Returning to FIG. 1 and continuing the explanation, as shown in an enlarged view in the drawing, the wafer holding means 50 of the present embodiment includes a wafer holding ring 52 capable of holding three types of wafers on which devices are formed, 53, 54, holding arms 52d, 53d, 54d for supporting the wafer holding rings 52, 53, 54 (see FIG. 7 for 54d), and for supporting the holding arms 52d, 53d, 54d A holding base 56 is provided on the lower surface of the front end of the frame 45. The holding base 56 has, for example, a substantially triangular prism shape, and three side wall surfaces of the holding base 56 are respectively formed with opening holes 56a, 56b, and 56c that open in the vertical direction (see FIG. 7 for 56c). ), The holding arms 52d, 53d, and 54d are connected to driving means (not shown) built in the holding base 56 through the opening holes 56a, 56b, and 56c. Further, the holding base 56 is configured to be rotatable in a direction indicated by an arrow 56d by a driving means (not shown), and the wafer holding rings 52, 53, 54 are positioned with respect to the position immediately above the wafer held on the holding table 64. It can be selectively positioned.

  Each of the wafer holding rings 52, 53, and 54 has an opening 58 that penetrates in the vertical direction and is formed in accordance with the dimensions of the wafer held by each of the wafer holding rings 52, 53, and 54, and annular step portions 52a, 53a on which the wafer is placed. , 54a are arranged along the inside of the wafer holding rings 52, 53, 54. A plurality of suction holes 52b, 53b, and 54b for sucking and holding the wafer to be placed are provided at predetermined intervals in the circumferential direction on the upper surfaces of the stepped portions 52a, 53a, and 54a. By being connected to the means, the wafer placed on the step portions 52a, 53a, 54a can be sucked and held. Linear portions 52c, 53c, and 54c are formed in the opening portions 58 of the wafer holding rings 52, 53, and 54, and the wafer holding rings 52, 53 are placed by placing the wafer orientation flats facing each other. , 54 can accurately define the direction of the wafer. The suction holes 52b, 53b, 54b and the suction means are connected to each other through suction passages formed along the wafer holding rings 52, 53, 54 and the holding arms 52d, 53d, 54d.

  The wafer holding rings 52, 53, 54 for holding the wafer can be rotated in the direction indicated by the arrow p by the driving means for supporting the holding arms 52d, 53d, 54d disposed in the holding base 56. Thus, both the front and back surfaces of the device wafer held by the wafer holding rings 52, 53, and 54 can be directed upward or downward. Further, the wafer holding rings 52, 53, 54 can be moved in the vertical direction indicated by the arrow q in accordance with a command from the control means, and can be accurately positioned at a desired height position. Yes.

  The die bonder 40 in this embodiment generally has the above-described configuration, and the devices bonded in this embodiment are a red LED, a green LED, and a blue LED, and the red LED, the green LED, and the blue LED are The formed wafer is an LED wafer, and the substrate to which the red LED, the green LED, and the blue LED are bonded is a module chip constituting a three-color LED, and a substrate on which a plurality of the module chips are formed is a module substrate The operation will be described by taking the case of the above as an example.

  As shown in FIG. 3A, the module substrate 10 has a substantially disk shape, the back surface 10b side is attached to the adhesive tape T, and is held by the annular frame F via the adhesive tape T (see FIG. 3A). (See 3 (b).) The module substrate 10 is formed with a diameter of 4 inches≈100 mm, and a substrate to which an LED is bonded, that is, a module chip 12 is formed in each region on the surface 10a side partitioned in a grid pattern by division lines.

  Each module chip 12 includes a housing region 121 formed of a concave portion having a rectangular opening to which a red LED is bonded and a rectangular to which a green LED is bonded, as shown in an enlarged view of a part of the module substrate 10 in the drawing. At least a housing region 122 made of a recess having a shape opening and a housing region 123 made of a recess having a rectangular opening to which a blue LED is bonded, and each bottom of each housing region 121 to 123 has an LED Two electrodes, i.e., bumps 124, which are opposed to the electrodes (anode electrode, cathode electrode) of each LED when the LED is housed are disposed.

  Six electrodes 125 are provided on the upper surface of the module chip 12 adjacent to the receiving areas 121 to 123 in the longitudinal direction. The electrodes 125 are electrically connected to the bumps 124 and 124 provided in the receiving areas 121 to 123. Electric power is supplied from the electrode 125 to the LEDs housed in the housing regions 121 to 123 via the bumps 124 and 124. The module chip 12 has an outer diameter of about 40 μm in the longitudinal direction and about 10 μm in the lateral direction in plan view, and the opening of each housing region is formed in a square shape with a side of 9 μm. Note that the module chip 12 represented on the module substrate 10 in FIG. 3 is shown larger than the actual size for the convenience of explanation, and is actually much smaller than the module chip 12 shown in FIG. A module chip 12 is formed on the module substrate 10.

  4A to 4C, an LED wafer 20 having a red LED 21 as a device bonded to the module chip 12 described above, an LED wafer 22 having a green LED 23, and a blue LED 25 are formed. The LED wafer 24 and partially enlarged sectional views AA, BB, and CC are shown. As shown in the drawing, each of the LED wafers 20, 22, and 24 has a substantially disk shape, and is configured with substantially the same dimensions as the module substrate 10 (diameter 4 inches≈100 mm). Each LED wafer 20, 22, 24 is red on the upper surface of an epitaxy substrate 201, 221, 241 such as a sapphire substrate or SiC substrate via a release layer 30 made of a Ga compound (for example, gallium nitride: GaN). The LED layer which comprises LED21 which emits light, LED23 which emits green light, LED25 which emits blue light (Hereinafter, LED21 is called red LED21, LED23 is green LED23, and LED25 is blue LED25.) Is formed. The red LED 21, green LED 23, and blue LED 25 are each formed with a size of 8 μm × 8 μm in plan view, an epitaxial layer composed of an N-type semiconductor layer, a light-emitting layer, and a P-type semiconductor layer, and an upper surface of the epitaxial layer And an electrode made of a P-type semiconductor and an N-type semiconductor (not shown). In each LED wafer 20, 22, 24, adjacent LEDs are divided and formed with predetermined intervals 202, 222, 242, and predetermined intervals 202, 222, 242 constituting the respective LEDs are formed. Since the masked area is masked when the LED layer is formed, the release layer 30 is exposed. As described above, the red LED 21, the green LED 23, and the blue LED 25 are modules each having a square shape with a side of 9 μm because each dimension is formed in a square shape with a side of 8 μm in plan view. It is possible to be accommodated in the accommodating areas 121 to 123 of the chip 12.

  On the outer periphery of each of the LED wafers 20, 22, 24, a linear portion indicating a crystal orientation, a so-called orientation flat OF is formed. A red LED 21, a green LED 23, and a blue LED formed on the upper surfaces of the LED wafers 20, 22, 24 are formed. The LEDs 25 are arranged in a predetermined direction with reference to the crystal orientation. It is known that red, green, and blue light emission in the red LED 21, green LED 23, and blue LED 25 is obtained by changing the material constituting the light emitting layer. For example, the red LED 21 is made of aluminum gallium arsenide (AlGaAs), green The LED 23 uses gallium phosphide (GaP), and the blue LED 25 uses gallium nitride (GaN). In addition, the material which forms red LED21 of this invention, green LED23, and blue LED25 is not limited to this, The well-known material for light-emitting each color can be employ | adopted, and each color is light-emitted using another material. It is also possible. In the present embodiment, as shown in FIGS. 4B and 4C, the LED wafers 22 and 24 having the green LED 23 and the blue LED 25 on the surface thereof are formed by the green LED 23, The blue LEDs 25 are formed on the surfaces of the LED wafers 22 and 24 at intervals 222 and 242 so that they do not overlap with the LEDs previously accommodated in the module chip 12. This point will be described in detail later.

  A process of bonding the red LED 21, the green LED 23, and the blue LED 25 to the module chip 12 formed on the module substrate 10 will be described with reference to FIGS. If the LED wafers 20, 22, 24 and the module substrate 10 described above are prepared, the red LED 21, the green LED 23, and the blue LED 25 of the LED wafers 20, 22, 24 are stored in predetermined receiving areas 121 to 123 of the module chip 12. A positioning step of positioning each LED in the predetermined receiving area 121-123 in which each LED is peeled off from the epitaxy substrates 201, 221, 241 and the red, green, and blue LEDs of the module chip are stored. An LED housing step is performed.

  First, the holding table 64 disposed on the substrate holding means 42 in the die bonder 40 shown in FIG. 1 is moved to the front substrate mounting region in the figure by operating the moving means 43. If the holding table 64 is moved to the position shown in FIG. 1, the front surface 10a of the module substrate 10 held by the frame F via the adhesive tape T is placed on the upper surface of the holding table 64, and the back surface 10b side is lowered. Then, the suction means (not shown) is operated and sucked and held on the holding table 64, and the frame F of the module substrate 10 is fixed by the clamp mechanism 65 disposed on the outer periphery of the holding table 64. For example, the module substrate 10 sucked and held on the holding table 64 is imaged by using the imaging unit 48 described above, and alignment is performed to align the condenser 44a of the laser beam irradiation unit 44 with the position of the module substrate 10. Run.

  When the alignment is completed by performing the alignment, the positions of the wafer holding rings 52, 53, and 54 are lowered downward by a command from a control means (not shown). When the wafer holding ring 52 is positioned in the state shown in FIG. 1, the LED wafer 20 on which the red LED 21 is formed is placed on the stepped portion 52 a of the wafer holding ring 52 as shown in FIG. As described above, when the LED wafer 20 is held on the wafer holding ring 52, the orientation flat OF of the LED wafer 20 is positioned on the straight portion 52c of the wafer holding ring 52, and the surface 20a on which the red LED 21 is formed is formed. By being placed upward, the wafer is accurately positioned in a desired direction with respect to the wafer holding ring 52 (see FIG. 5B).

  When the LED wafer 20 is placed on the stepped portion 52a, a suction means (not shown) is operated to suck the LED wafer 20 from the suction hole 52b and bring the LED wafer 20 into a suction holding state. If the LED wafer 20 is sucked and held by the wafer holding ring 52, the driving means of the holding base 56 is operated to rotate the wafer holding ring 52 by 180 ° in the direction of the arrow p in the figure as shown in FIG. Then, the back surface 20b side of the LED wafer 20 is exposed upward, and the direction is changed so that the front surface 20a on which the red LED 21 is formed faces downward. This completes the holding of the LED wafer 20.

  When the holding of the LED wafer 20 is completed, the holding base 56 is rotated by 120 ° in the direction indicated by the arrow 56d in FIG. 1, and the wafer holding ring 53 is moved to the position where the holding ring 52 shown in FIG. If the wafer holding ring 53 is moved in this way, the stepped portion 53a of the wafer holding ring 53 is replaced with the LED wafer 22 on which the green LED 23 is formed as shown in FIG. Placed on. At this time, similarly to the LED wafer 20, when the LED wafer 22 is held on the wafer holding ring 53, the orientation flat OF of the LED wafer 22 is positioned on the straight portion 53 c of the wafer holding ring 53, and the green LED 23 is formed. The front surface 22a is placed facing upward, and is accurately positioned in a desired direction with respect to the wafer holding ring 53 (see FIG. 6B).

  When the LED wafer 22 is placed on the stepped portion 53a, a suction means (not shown) is operated to suck the LED wafer 22 from the suction hole 53b and bring the LED wafer 22 into a suction holding state. If the LED wafer 22 is sucked and held by the wafer holding ring 53, the driving means of the holding base 56 is operated to move the wafer holding ring 53 in the direction of the arrow p in the figure in the same manner as shown in FIG. , And the direction is changed so that the surface 22a on which the green LED 23 is formed faces downward. This completes the holding of the LED wafer 22.

  When the holding of the LED wafer 22 is completed, the holding base 56 is further rotated by 120 ° in the direction indicated by the arrow 56d in FIG. 1, and the wafer holding ring 54 is moved to the position where the wafer holding ring 53 was located. When the wafer holding ring 54 is moved, the LED wafer 24 on which the blue LED 25 is formed is placed on the stepped portion 54 a of the wafer holding ring 54 in the same manner as the LED wafers 20 and 22 described above. Similar to the LED wafers 20 and 22, when the LED wafer 24 is held on the wafer holding ring 54, the orientation flat OF of the LED wafer 24 is positioned on the straight portion 54c of the wafer holding ring 54, and the surface on which the blue LED 25 is formed. 24a is placed facing upward and positioned accurately in a desired direction with respect to the wafer holding ring 54 (see FIG. 7B).

  When the LED wafer 24 is placed on the stepped portion 54a, a suction means (not shown) is operated to suck the LED wafer 24 from the suction hole 54b and bring the LED wafer 24 into a suction holding state. When the LED wafer 24 is sucked and held by the wafer holding ring 54, the driving means of the holding base 56 is operated to cause the wafer holding ring 54 to be indicated by the arrow p in the figure, as shown in FIG. The direction is changed so that the surface 24a on which the blue LED 25 is formed is turned downward by rotating 180 ° in the direction. This completes the holding of the LED wafer 24.

  When the LED wafers 20, 22, and 24 are held on the wafer holding rings 52, 53, and 54 as described above, the wafer holding ring 52 that sucks and holds the LED wafer 20 in preparation for the bonding process described later is shown in FIG. Move to the position shown in. In the above-described embodiment, each time the LED wafers 20, 22, and 24 are placed on the wafer holding rings 52, 53, and 54, the back surface is rotated in the direction of the arrow p each time to turn upward. For example, after the three LED wafers 20, 22, and 24 are placed on the wafer holding rings 52, 53, and 54, the wafer holding rings 52, 53, and 54 are simultaneously rotated in the direction of the arrow p. You may make it make it.

  As described above, when the LED wafers 20, 22, and 24 are placed on the wafer holding rings 52, 53, and 54 and the surface side on which the red LED 21, the green LED 23, and the blue LED 25 are disposed is directed downward, Based on the positional information obtained by executing the alignment, the moving means 43 is operated to position the holding table 64 directly below the condenser 44a and the wafer holding ring 52 (see FIG. 8). When the holding table 64 is positioned immediately below the wafer holding ring 52, the driving means (not shown) of the holding base 56 that functions as the facing means of the present invention is operated so that the LED wafer 20 faces the module substrate 10. Then, the wafer holding ring 52 is lowered toward the module substrate 10 on the holding table 64. At this time, the LED wafer 20 is brought close to the surface 10a of the module substrate 10 as can be understood from FIG. 9A, which shows the positional relationship when the LED wafer 20 and the module substrate 10 are viewed from the side. As a result, the housing area 121 of the module chip 12a is positioned in a state of being close to the LED wafer 20 immediately below the red LED 21a. 9 to 11, the wafer holding rings 52, 53, and 54 holding the LED wafers 20, 22, and 24 are omitted for convenience of explanation.

  Returning to FIG. 9 and continuing the description, when the housing area 121 of the module chip 12a is positioned immediately below the red LED 21a of the LED wafer 20, the laser beam irradiation means 44 is operated to move the red LED 21a to the housing area 121. Bond. More specifically, a laser beam is oscillated by the laser oscillator 44b of the laser beam irradiation unit 44 according to a command from the control unit, and the X axis AOD 44d1 and the Y axis AOD 44d2 are operated to adjust the incident position with respect to the fθ lens 44g. The laser beam LB is irradiated from the back surface 20b side of the LED wafer 20 toward the peeling layer 30 located on the back surface of the red LED 21a serving as a target.

In addition, the laser beam irradiation conditions of the die bonder 40 in this embodiment are set as follows, for example.
Laser beam wavelength: 266 nm
Repetition frequency: 50 kHz
Average output: 0.25W
Spot diameter: φ10μm

  The wavelength of the laser beam is set to a wavelength that is transmissive to the epitaxy substrate 201 constituting the LED wafer 20 and absorbable to the release layer 30. As a result, the release layer 30 is destroyed, and a gas layer is instantaneously formed on the boundary surface between the epitaxy substrate 201 and the red LED 21a to form a shock wave, and the red LED 21 is peeled from the epitaxy substrate 201. The red LED 21a peeled off from the LED wafer 20 is already very close to the housing area 121 of the module chip 12 before being peeled from the LED wafer 20, and is housed in the housing area 121 when it is peeled off. Is done.

  When the red LED 21a is peeled from the LED wafer 20 and accommodated in the accommodating area 121 of the module chip 12a, the X-direction moving means 80 of the moving means 43 functioning as the device positioning means of the present invention is operated to 9B, a predetermined amount is moved in the direction indicated by the arrow, and the accommodation area 121 for accommodating the red LED 21b in the next module chip 12b is positioned immediately below the next red LED 21b. If the accommodation area 121 of the module chip 12b is positioned immediately below the red LED 21b, the X-axis AOD 44d1 and the Y-axis AOD 44d2 of the laser beam irradiation unit are controlled by the command from the control unit, and the irradiation position of the laser beam LB is changed. Then, the peeling layer 30 located on the back surface of the red LED 21b is irradiated. Thereby, the peeling layer 30 located on the back surface of the red LED 21b is broken, the red LED 21b is peeled from the LED wafer 20 similarly to the red LED 21a, and the red LED 21b is accommodated in the accommodation area 121 of the module chip 12b. Further, by performing the same process as described above, the next red LED 21c is accommodated in the accommodation area 121 of the module chip 12c formed adjacent to the module chip 12b. When the red LEDs 21 are accommodated in all the module chips 12 arranged in the X direction in this way, the module substrate 10 is indexed in the Y direction and all the module chips 12 arranged in the X direction again. The red LED 21 on the LED wafer 20 is accommodated in the accommodation area 121. By repeating such positioning process and LED housing process, the red LEDs 21 are housed in the housing areas 121 of all the module chips 12 on the module substrate 10. Here, as understood by referring to the module chip 12 a described in FIG. 9B, the LED 21 accommodated in the module chip 12 protrudes upward from the surface of the module chip 12. The red LEDs 21 are accommodated in the accommodating areas 121 of the module chips 12, so that the bumps 124 and 124 formed on the bottom of the accommodating area 121 are electrodes made of P-type semiconductors and N-type semiconductors on the red LEDs 21. In this embodiment, a bond layer in which a bond material made of an anisotropic conductor is laminated is formed in advance on the tip ends of the bumps 124 and 124, whereby the electrode on the red LED 21 side and the bumps are formed. 124 and 124 are electrically connected, and the bonding of the red LED 21 is completed.

  If the red LEDs 21 are bonded to all the module chips 12 formed on the module substrate 10, the positioning process and the accommodating process for bonding the green LEDs 23 to the predetermined accommodating regions 122 of the respective module chips 12 are performed next. To do. More specifically, after bonding the red LED 21 as described above, the wafer holding ring 52 is raised, the holding base 56 is rotated by 120 ° in the direction indicated by the arrow 56d in FIG. 1, and the LED wafer 22 is held. The wafer holding ring 53 is moved to the position where the wafer holding ring 52 was located. Then, the moving means 43 is operated again to position the module substrate 10 at a predetermined position (directly below) with respect to the LED wafer 22. At this time, the module substrate 10 is positioned so that the accommodation area 122 formed in the module chip 12 a is directly below the predetermined green LED 23 a of the LED wafer 22. When the module substrate 10 is moved directly below the LED wafer 22, the driving means (not shown) of the holding base 56 that functions as the facing means of the present invention is operated to lower the wafer holding ring 53, thereby The wafer 22 is brought close to the surface 10a of the module substrate 10 (see FIG. 10A).

  Details of the LED wafer 22 in this embodiment will be further described. As can be understood from the LED wafer 22 shown in FIG. 4B and FIG. 10, the green LEDs 23 arranged on the LED wafer 22 are arranged at a predetermined interval 222, as shown in FIG. It is formed wider than the predetermined interval 202 of the red LED 21 disposed on the LED wafer 20 shown. Here, the predetermined interval 222 in the LED wafer 22 is set such that when the green LED 23 of the LED wafer 22 is brought close to the module chip 12 to be bonded, as shown in FIG. Is set so as not to overlap with the red LED 21 accommodated in the plan view. Accordingly, as shown in FIG. 10A, even if the LED wafer 22 is brought close to the module substrate 10 in order to bond the green LED 23 to the module chip 12, the green LED 23 is provided by the predetermined interval 222. However, the green LED 23 does not overlap the red LED 21 already accommodated in the module chip 12, and can be brought close to a position suitable for bonding the green LED 23 to the predetermined accommodation region 122.

  When the description is continued with reference to FIG. 10A, if the housing region 122 of the module chip 12a is positioned in the vicinity of the green LED 23a of the LED wafer 22 by performing the positioning step, the red color described above is obtained. Similarly to the bonding of the LED 21, the laser beam irradiating means 44 is operated to perform the LED housing process for housing the green LED 23 a in the housing area 122. That is, from the back surface 22b side of the LED wafer 22, a laser beam LB having a wavelength that is transmissive to the epitaxy substrate 221 and absorbable to the release layer 30 is applied to the back surface of the target green LED 23a. Irradiation is performed toward the release layer 30 located. Thereby, the peeling layer 30 is destroyed, a gas layer is formed on the boundary surface between the epitaxy substrate 221 and the green LED 23a, and the green LED 23a is peeled from the epitaxy substrate 221. The green LED 23 a peeled off from the LED wafer 22 is accommodated in the accommodating area 122.

  If the green LED 23a is accommodated in the accommodating area 122 of the module chip 12a, the moving means 43 functioning as the device positioning means of the present invention is activated to move the module substrate 10 in the direction of the arrow shown in FIG. It moves, and the accommodation area | region 122 in the next module chip | tip 12b is positioned just under the next green LED23b. As can be understood from FIG. 10B, when the LED wafer 22 is close to the module substrate 10, the lower end of the green LED 23 formed on the LED wafer 22 is first accommodated in the module chip 12. The module substrate 10 cannot be moved in the direction of the arrow in the figure as it is because it is lower than the upper end of the red LED 21. Therefore, when the movement in the direction of the arrow is performed by the moving means 43, the wafer holding ring 53 for holding the LED wafer 22 is actuated once by operating the driving means provided on the holding base 56, and the module substrate 10 Is moved again for a predetermined distance and then moved down again to bring it close to the module substrate 10.

  As described above, if the housing area 122 of the module chip 12b is positioned directly below the green LED 23b, the X direction AOD 44d and the Y direction AOD 44e of the laser beam irradiation means are controlled by a command from the control means. The position of the laser beam LB incident on the fθ lens 44g is positioned at a predetermined position, and is applied to the release layer 30 positioned on the back surface of the green LED 23b. Thereby, the peeling layer 30 located on the back surface of the green LED 23b is destroyed, the green LED 23b is peeled from the LED wafer 22, and the green LED 23b is accommodated in the accommodation area 122 of the module chip 12b. At this time, as described above, the bumps 124 and 124 are formed with a bond layer in which a bond material made of an anisotropic conductor is laminated, and the electrode of the green LED 23 and the bumps 124 and 124 are electrically connected by the bond material. Connected and die bonded. Then, by repeating the same process further, the next green LED 23c is housed and die-bonded in the housing area 122 of the module chip 12c formed adjacent to the module chip 12b. If the green LEDs 23 are bonded to all the module chips 12 arranged in the X direction in this way, the module substrate 10 is indexed in the Y direction, and all the module chips 12 arranged in the X direction again. The green LED 23 on the LED wafer 22 is bonded to the accommodation area 122. By repeating such positioning process and LED housing process, the green LEDs 23 are die-bonded to the housing areas 122 of all the module chips 12 on the module substrate 10. As described above, the green LEDs 23 formed on the LED wafer 22 are arranged at a wider interval than the case where the red LEDs 21 are formed on the LED wafer 20, and the green LEDs 23 are arranged on the LED wafer 22. The number of LEDs 23 is approximately ½ of the LED wafer 20 on which the red LED 21 is disposed, and approximately two LED wafers 22 are required for one LED wafer 20. If all the upper green LEDs 23 are bonded, the new LED wafer 22 on which the green LEDs 23 are formed is replaced.

  If the green LEDs 23 are bonded to all the module chips 12 formed on the module substrate 10, the positioning process and the LED accommodating process for accommodating the blue LEDs 25 in the predetermined accommodating regions 123 of the respective module chips 12 are performed next. carry out. More specifically, after bonding the red LEDs 21 and the green LEDs 23 to all the module chips 12 on the module substrate 10 as described above, the wafer holding ring 53 is raised and the holding base 56 is moved to the arrow 56d in FIG. The wafer holding ring 54 that sucks and holds the LED wafer 24 on which the blue LED 25 is disposed is moved to the position where the wafer holding ring 53 was located. Then, the moving means 43 is operated again to position the module substrate 10 directly below the LED wafer 24. At this time, in the module substrate 10, the accommodation area 123 formed in the module chip 12 a is positioned immediately below the predetermined blue LED 25 a of the LED wafer 24. Then, if the module substrate 10 is moved directly below the LED wafer 24, the LED wafer 24 is moved to the surface of the module substrate 10 by operating a driving means (not shown) of the holding base 56 to lower the wafer holding ring 54. 10a (refer to FIG. 11A).

  Details of the LED wafer 24 in this embodiment will be further described. As can be understood from the description of the LED wafer 24 illustrated in FIG. 4C and FIG. 11, the blue LEDs 25 disposed on the LED wafer 24 are disposed with a predetermined interval 242 therebetween. 10 is formed wider than the predetermined interval 222 in which the green LEDs 23 arranged on the LED wafer 22 shown in FIG. Here, the predetermined interval 242 in the LED wafer 24 is such that when the blue LED 25 of the LED wafer 24 is brought close to the module chip 12 as shown in FIG. It is set so as not to overlap with the accommodated red LED 21 and green LED 23 in plan view. Accordingly, as shown in FIG. 11A, even if the LED wafer 24 is brought close to the module substrate 10 to bond the blue LED 25 to the module chip 12, the red LED 21 already contained in the module chip, In addition, the blue LED 25 can be brought close to a position suitable for bonding to the predetermined accommodation region 123 without overlapping with the green LED 23.

  When the description is continued with reference to FIG. 11A, if the blue LED 25a of the LED wafer 24 is positioned so as to be close to the housing region 123 of the module chip 12a by performing the positioning step, the red LED 21, Similarly to the LED housing process in which the green LED 23 is housed in the module chip 12 a, the laser beam irradiation means 44 is operated to bond the blue LED 25 a to the housing region 123. That is, from the back surface 24b side of the LED wafer 24, a laser beam LB having a wavelength that is transmissive to the epitaxy substrate 241 and absorbable to the release layer 30 is applied to the back surface of the target blue LED 25a. Irradiation is performed toward the release layer 30 located. Thereby, the peeling layer 30 is destroyed, a gas layer is formed on the boundary surface between the epitaxy substrate 241 and the blue LED 25a, and the blue LED 25a is peeled from the epitaxy substrate 241. The blue LED 25a peeled off from the LED wafer 24 is housed and bonded in the housing region 123 when peeled off.

  If the blue LED 25a is accommodated in the accommodating area 123 of the module chip 12a, the moving means 43 is operated to move the module substrate 10 by a predetermined amount in the direction of the arrow shown in FIG. 11B, and in the next module chip 12b An accommodation region 123 for accommodating the blue LED 25b is positioned immediately below the next blue LED 25b (positioning step). As in the case where the green LED 23 is accommodated in the module chip 12, the lower end of the blue LED 25 formed on the LED wafer 24 is accommodated first in the module chip 12 when the LED wafer 24 is in proximity to the module substrate 10. Since the red LED 22 and the green LED 24 are positioned lower than the upper ends, the module substrate 10 cannot be moved in the direction of the arrow in the drawing as it is. Therefore, when the movement in the direction of the arrow is performed by the moving means 43, the wafer holding ring 52 that holds the LED wafer 24 is once raised, the module substrate 10 is moved a predetermined distance, and then lowered again to bring the module substrate 10 The operation to make it close to is performed.

  As described above, if the receiving area 123 of the next module chip 12b is positioned immediately below the next blue LED 25b, the X direction AOD44d1, Y direction of the laser beam irradiating means is specified by the control means. The AOD 44d2 is controlled, the irradiation position of the laser beam LB is changed, and the peeling layer 30 positioned on the back surface of the blue LED 25b is irradiated. Thereby, the peeling layer 30 located on the back surface of the blue LED 25b is destroyed, and the blue LED 25b is peeled off from the LED wafer 24 in the same manner as the blue LED 25a, and the blue LED 25b is housed in the housing region 123 of the module chip 12b. By further executing the same positioning process and LED housing process, the next blue LED 25c is housed in the housing area 123 of the module chip 12c formed adjacent to the module chip 12b. When the blue LEDs 25 are accommodated in all the module chips 12 arranged in the X direction in this way, the module substrate 10 is indexed in the Y direction, and all the module chips 12 arranged in the X direction are again transmitted. The blue LED 25 on the LED wafer 24 is accommodated in the accommodation area 123. As described above, the bumps 124 and 124 are formed with a bond layer in which a bond material made of an anisotropic conductor is laminated, and the blue LED 25 on the LED wafer 24 is placed on the housing area 123 of the module chip 12. By housing, the module chip 12 and the electrode of the blue LED 25 are electrically connected through the bond material, and die bonding is completed. By repeating the positioning process and the LED housing process, the blue LEDs 25 are housed in the housing areas 123 of all the module chips 12 on the module substrate 10. As described above, the blue LEDs 25 formed on the LED wafer 24 are arranged at a wider interval than the case where the green LEDs 23 are formed on the LED wafer 22 and are arranged on the LED wafer 24. The number of blue LEDs 25 is approximately 1/3 of the LED wafer 20 on which the red LEDs 21 are disposed, and approximately three LED wafers 24 are required for one LED wafer 20. Therefore, when all the blue LEDs 25 on the LED wafer 24 are die-bonded on the module substrate 10 and the blue LEDs 25 are continuously bonded, they are replaced with new LED wafers 24 on which the blue LEDs 25 are formed.

  As described above, when red, green, and blue LEDs are bonded to all the module chips 12 disposed on the module substrate 10, the assembly of the module is completed. If the LEDs are bonded to all the module chips 12 described above, an individualization process for individualizing each module chip 12 may be performed by a known method. In the LED singulation process, for example, an appropriate laser processing apparatus is applied, and a laser beam having a wavelength that is absorptive with respect to the material of the module substrate 10 is irradiated along the planned division lines that partition the module chip 12. However, since the method of dividing the substrate by the laser processing apparatus is well known, the details are omitted.

The present invention is not limited to the above-described embodiments, and modifications can be assumed as appropriate as long as they belong to the technical scope of the present invention.
For example, in the above-described embodiment, the device to be bonded is described as the red, green, and blue LEDs 21, 23, and 24 formed on the LED wafers 20, 22, and 24, and the substrate to which the device is bonded is described as the module chip 12. The die bonder of the present invention is not limited to this. For example, the present invention may be applied to a die bonder for bonding a plurality of devices including integrated circuits such as IC and LSI to a wiring board constituting a chip size package (CSP). Good. For example, a device wafer is prepared in which a plurality of semiconductor devices such as IC, LSI, etc. are partitioned by the planned dividing line and formed on the upper surface of the silicon substrate, and the finished thickness of the device corresponds to the finished thickness along the scheduled dividing line from the surface side first. After forming a groove by dicing to a depth of about, a so-called first dicing is performed in which the thinning process of the device is performed by grinding the back surface side and the dividing process of dividing into individual devices is performed at the same time. Then, you may form the device wafer applied to the die bonder of this invention by sticking this several device through the bond layer comprised by bond materials, such as an epoxy resin, on the upper surface of a glass substrate. In that case, the bond layer becomes a release layer, the laser beam having the focus on the bond layer is irradiated from the glass substrate side, that is, the back surface side of the device wafer, the bond layer is destroyed by the shock wave of the laser beam, and the device is connected to the wiring board. Can be bonded to the side.

  In the die bonder in the embodiment described above, the substrate holding means is provided with three wafer holding rings in order to hold the three types of LED wafers which are device wafers at the same time, but the present invention is not limited to this, and two or more types are provided. The device wafer may be configured to be held.

10: Module substrate 12: Module chip 121-123: Accommodating area 124: Bump 125: Electrode 20, 22, 24: LED wafer 21: Red LED
23: Green LED
25: Blue LED
40: Laser processing apparatus 42: Substrate holding means 43: Moving means 44: Laser beam irradiation means 44a: Condenser 44b: Laser oscillator 44c: Attenuator 44d: X-axis AOD
44e: Y-axis AOD
44h: Polygon mirror 50: Wafer holding means 52, 53, 54: Wafer holding ring

Claims (9)

A die bonder for bonding a device to a substrate,
A substrate holding means having a holding surface defined in the X-axis direction and the Y-axis direction for holding the substrate to which the device is bonded;
A wafer holding means for holding the outer periphery of the wafer having a plurality of devices disposed on the surface via a release layer;
Facing means for causing the surface of the wafer held by the wafer holding means to face the upper surface of the substrate held by the substrate holding means;
Device positioning means for moving the substrate holding means and the wafer holding means relative to each other in the X and Y directions to position a device disposed on the wafer at a predetermined position on the substrate;
A laser irradiation means for irradiating a laser beam from the back surface of the wafer to destroy the peeling layer of the corresponding device and bonding the device to a predetermined position on the substrate;
A die bonder consisting of at least.   The substrate is provided with an electrode facing the electrode of the device, a bond layer is laid on the substrate side or the device side, and the device is mounted by a shock wave of a laser beam irradiated corresponding to the device. The die bonder according to claim 1, wherein bonding is performed at a predetermined position.   The die bonder according to claim 2, wherein the bond layer has an anisotropic conductor.   2. The die bonder according to claim 1, wherein two or more wafer holding means are disposed, and two or more kinds of devices are selectively positioned on the substrate.   The laser beam irradiation means includes a laser oscillator that oscillates a pulsed laser beam, an fθ lens that focuses the laser beam oscillated by the laser oscillator on a release layer of the wafer held by the wafer holding means, the laser oscillator and the fθ lens And a positioning unit for positioning the laser beam on a corresponding device disposed between the die bonder and the die bonder according to claim 1.   6. The die bonder according to claim 5, wherein the positioning unit includes at least an X direction AOD for deflecting a laser beam oscillated by the laser oscillator in the X direction and a Y direction AOD for deflecting in the Y direction.   6. The die bonder according to claim 5, wherein the positioning unit includes at least an X-direction resonant scanner that deflects a laser beam oscillated by the laser oscillator in the X direction and a Y-direction resonant scanner that deflects the laser beam in the Y direction.   6. The die bonder according to claim 5, wherein the positioning unit includes at least an X-direction galvano scanner that deflects a laser beam oscillated by the laser oscillator in the X direction, and a Y-direction galvano scanner that deflects the laser beam in the Y direction.   The die bonder according to any one of claims 6 to 8, wherein the laser beam irradiation means further includes a polygon mirror in addition to the positioning unit.