JP3436071B2 - Application method of bond for bonding electronic parts - Google Patents

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a method for applying an electronic component bonding bond for bonding an electronic component to a substrate. 2. Description of the Related Art In order to bond various kinds of electronic components to a substrate, a bond is applied to a predetermined position of the substrate. In this case, if the applied amount of the bond is too small, the adhesive strength of the electronic component may be insufficient, and if the amount is too large, the electronic component may be buried in the bond. Must be adjusted. [0003] The adjustment of the amount of coating is performed by:
Conventionally, it has been performed by changing the magnitude of the gas pressure for pressurizing the bond stored in the syringe, the pressurizing time, and the like. However, when the bond is applied by the bond applying device, there are other factors that influence the amount of the bond applied, other than the factors such as the magnitude of the gas pressure and the pressurizing time.
For example, even if the gas pressure and the pressurizing time are controlled optimally, the amount of the bond applied to the substrate varies. As a factor of this variation, there is variation in the distance between application points. That is, generally, the bond is applied to a predetermined application point of the substrate by pressurizing the bond in the syringe with gas pressure while moving the syringe relatively horizontally with respect to the substrate, but the distance between the application points is large. Is not constant, so the amount of bond applied and ejected to the lower end of the nozzle by gas pressure changes while the syringe moves toward the target application point, and as a result, The amount of bonds to be made will vary. Accordingly, the present invention provides a method for applying a bond for bonding electronic parts, which does not have a variation in the amount of the bond applied to a large number of application points on a substrate and can perform a stable bond application at a high speed. With the goal. According to the present invention, a bond is provided at the lower end of a nozzle by applying gas pressure to a bond in a syringe while horizontally moving the syringe relative to a substrate. A method of applying a bond for electronic component bonding, wherein the bonding is performed by discharging and attaching, and applying and bonding a bond attached to a lower end portion of a nozzle to a plurality of application points on a substrate having different distances between application points. The application of the gas pressure is started at a timing retroactive to the same predetermined time preset for all the application points from each application timing determined based on the position data of the application points. According to the present invention having the above structure, the same predetermined time preset for all application points is applied from each application timing determined based on the position data of each application point. By starting the application of the gas pressure at the specified timing, it is possible to apply the bond with a stable application amount. Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a bond application apparatus according to an embodiment of the present invention, FIG. 2 is a perspective view of a substrate showing a bond application mode by the bond application apparatus, and FIG. 3 is control of the bond application apparatus. Block diagram of the system, FIG. 4 (a), (b),
(C) is an enlarged view of a nozzle of the coating apparatus of the bond, and FIG.
5A is a timing chart of a coating operation of the bond applying apparatus, FIG. 5B is an enlarged view of a nozzle of the bond applying apparatus, and FIG. 5C is a bottom view of a nozzle of the bond applying apparatus. FIG. 6A is a graph showing a bond adhesion amount, and FIG.
FIG. 6B is an enlarged view of a nozzle of the bond applying apparatus, and FIG. 6C is a graph showing a bond adhesion amount at a lower end portion of the nozzle of the bond applying apparatus. First, the overall structure of a bond applying apparatus will be described with reference to FIG. In FIG. 1, the main body frame 11
A transparent cover box 12 is covered on the upper part of the box, and components described below are arranged inside the cover box 12. Reference numeral 13 denotes an X table, and 14 denotes a Y table disposed on both sides of the X table 13 so as to be orthogonal thereto. The X table 13 has a head 15 mounted thereon. The head 15 holds a plurality of syringes 16 and the camera 10. Bonds are stored in each of the syringes 16, but the amount of the bond applied by each of the syringes 16 is different and is selectively used according to a target substrate, a target chip, or the like. Motors Mx and My and ball screws 18 driven and rotated by the motors Mx and My are provided on the X table 13 and the Y table 14, which are moving tables.
When the motors Mx and My are driven, the head 15 moves in the X direction or the Y direction, and the syringe 16 moves horizontally relative to the substrate 20. It should be noted that only a part of the motors Mx and My and the ball screw 18 are shown for convenience of drawing. Below the moving path of the head 15, a pair of right and left bar-shaped guide rails 19a and 19b are provided. On the inner surfaces of the guide rails 19a and 19b, a conveyor belt 21 for transporting the substrate 20 is provided.
A clamper 1 is provided at the center of one of the guide rails 19a.
9c is provided, and the substrate 20 is pressed against the other guide rail 19b and fixed. Therefore, the guide rail 19b and the clamper 19c constitute a positioning portion of the substrate 20. Then, the substrate 20 thus positioned
Is applied to the substrate. Reference numeral 22 denotes a conveyor belt driving motor;
3 moves one guide rail 19a relative to the other guide rail 19b in the width direction (Y direction) of the substrate 20 to adjust the distance between the guide rails 19a and 19b according to the width of the substrate 20. Motor for the
24 is the guide. Next, the trial application section 30 of the bond 1 provided on the side of the guide rail 19b will be described. A pay-out reel 31 and a take-up reel 32 are provided on the side of the guide rail 19b, and the tape 33 wound around the pay-out reel 31 is taken up by the take-up reel 32. The tape 33 is a transparent or translucent light transmissive tape, and is made of a synthetic resin or the like. A light source unit (not shown) having a light source is provided below the horizontal running portion of the tape 33, and irradiates light toward the tape 33. Numeral 34 denotes a cradle for the tape 33 disposed immediately below the horizontal running portion of the tape 33 for holding the tape 33 horizontally.
It is formed of a transparent or white light transmitting plate. The horizontal running portion of the tape 33 serves as a stage for trial application of the bond. FIG. 2 shows a manner of applying a bond.
The syringe 16 ejects the bond 1 from the nozzle 16a while moving horizontally on the substrate 20 in the X direction or the Y direction,
0 predetermined application point P (P1, P2, P3,... Pn)
In order. In the figure, D (D1, D2, D3,...)
Dn) is the movement distance of the syringe between each application point. As will be described later in detail, the present bond applying apparatus moves the syringe 16 at a high speed between the application points having different moving distances D, and discharges the bond 1 from the nozzle 16a. By adjusting the timing at which the bond 1 is applied, stable application of the bond 1 with a uniform application amount at each of the application points P1 to Pn is realized. Next, the configuration of a control system of the bond applying apparatus will be described. In FIG. 3, reference numeral 40 denotes a main control unit,
It receives data from each unit described below and issues commands to each unit to control the overall operation. Application data storage unit 4
1 stores the coordinates of each application point of the substrate 20 to be applied. The application condition storage unit 42 stores a pressurizing time for discharging the bond 1. Coating condition adjustment data storage unit 43
Stores the adjustment data of the above-described pressurization time. The recognition unit 44 calculates the application area of the bond 1 applied to each application point based on the image data of each application point captured by the camera 10. This application area is
It is used as an index indicating the amount of the bond 1 applied at each application point. The motor drive unit 45 includes a motor M for each axis of the X table 13 and the Y table 14 for horizontally moving the syringe 16.
It controls x, My, and a Z-axis motor Mz that moves the syringe 16 up and down. The valve driving unit 46 controls the operation of a pressurizing valve 47 that applies gas pressure to the syringe 16. The bond applying apparatus has the above-described configuration, and a method of applying an electronic component bonding bond by the bond applying apparatus will be described below. First, before describing the specific operation of the coating apparatus, a method of coating the bond 1 using gas pressure will be described with reference to FIG.
As shown in FIG. 4A, in this bond application apparatus, the gas pressure is applied to the syringe 16 so that the syringe 16
The bond 1 is ejected from the lower end of the nozzle 16a attached to the nozzle 16a, and the bond 1 is adhered to the lower end of the nozzle 16a (the amount Q of the bond 1 is hereinafter referred to as "adhered amount"). Then, as shown in FIG. 4B, the bond 1 is applied by lowering the nozzle 16a and landing the bond 1 attached to the lower end of the nozzle 16a on the substrate 20. Therefore, as shown in FIG. 4B, the nozzle 1a at the timing at which the application is performed (the timing at which the nozzle 16a descends and the bond 1 discharged to the lower end thereof lands on the substrate 20).
The amount Qe of the bond 1 adhering to the lower end of the substrate 6a (hereinafter referred to as “adhesion amount at the time of application”) Qe is equal to the amount Qt of the bond 1 actually applied to the substrate 20 (the amount of the bond 1 shown in FIG. amount,
Hereinafter, the amount is simply referred to as “application amount”.
In other words, if the adhesion amount Qe during application is large, the application amount Qt
Increases, and conversely, the smaller the amount, the smaller the coating amount Qt.
Therefore, in order to realize stable application of the bond 1 having a uniform application amount Qt to each application point, it is necessary to make the application amount Qe at each application point constant. Next, the relationship between the adhesion amount Qe during coating and the opening / closing timing of the pressure valve 47 will be described with reference to FIG. In FIG. 5, (a) shows a pressure valve 47
6 is a timing chart showing opening / closing timings of FIG. FIG. 3B shows the change in the amount Q of the bond 1 discharged by applying a gas pressure into the syringe 16 at each timing. (C) shows the nozzle 1
6 shows a temporal change in the amount Q of adhesion of the bond 1 adhering to the lower end of 6a. In FIG. 5, the time origin t0 is a timing at which a series of operations is started. At this timing t0, the pressurizing valve 47 is opened, and the discharge of the bond 1 is started from the lower end of the nozzle 16a. In FIG. 5, broken arrows A and B indicate the flow direction of the bond 1 in the nozzle 16a. The pressurizing valve 47 is opened for a preset time (pressurizing time Td) and closed at a timing t1. As shown in FIGS. 5B and 5C, the adhesion amount Q of the bond 1 discharged to the lower end of the nozzle 16a is the adhesion amount of the bond 1 at the operation start timing (a), that is, the initial amount. It gradually increases from the adhesion amount Qi, and reaches the maximum amount Qm at the timing t1 when the pressurizing valve 47 is closed through the state of (b) and (c) as shown in (c). After this, pressurizing valve 4
After the nozzle 7 is closed, the bond 1 flows backward in the nozzle 16 toward the syringe 16 as shown by the arrow B as shown in (d), and the amount of adhesion Q of the bond 1 becomes a certain time (FIG. 5 (c)). During the period from t1 to t2, which is referred to as “return time” Tw), the decrease is continued, and the phenomenon of so-called “return” of bond 1 is shown. In (d), bond 1 indicated by a broken line is the maximum amount Qm.
, And bond 1 indicated by a solid line indicates bond 1 that is decreasing due to “return”. And this time Tw
(After timing t2), the adhesion amount Q of the bond 1 becomes the constant amount Qr shown in (e) and (f). As described above, the adhesion amount Q of the bond 1
Becomes a constant amount Qr after temporarily increasing or decreasing after the ejection start timing t0. There are basically two methods for performing application such that the applied amount Qe at the time of application becomes a constant amount with respect to the applied amount Q of the bond 1 that fluctuates with time. That is, one is a method in which the coating is performed after the adhesion amount Q becomes the fixed amount Qr, that is, after the timing t2, and the other is a method in which the adhesion amount Q during application is changed while the adhesion amount Q is fluctuating.
This is a method in which application is performed while taking measures to keep e at a constant amount. The former is a method that has been used conventionally, and according to this method, application is performed after the amount of adhesion Q has reached a fixed amount Qr, so that the amount of adhesion Qe during application is always constant. However, this method has a problem in that the application must wait until the time t2 elapses after the timing t0 of the start of the discharge, and thus the application interval becomes longer, resulting in a longer tact time. Therefore, in order to reduce the tact time and achieve high-speed coating, the latter method is adopted. In this case, however, the nozzle is not allowed to return during the return time Tw in which the adhesion amount Q fluctuates. Bond 1 must be applied by lowering 16a. Bond 1 during this return time Tw
Has been conventionally performed, but conventionally, as a method of setting the timing of starting the discharge of the bond 1,
The timing of the start of ejection has been synchronized with the timing of the start of movement of the syringe 16 in the horizontal direction. Therefore, if the moving distance D between the application points is different, the time required for the syringe 16 to reach the position of the application point is different, so that the time from the start of ejection to the application to the substrate 20 is different, and the return time Tw The timing of the application inside is not constant. As described above, since the adhesion amount Q of the bond 1 gradually decreases during the return time Tw, the adhesion amount Qe at the time of application at each application point varies depending on the moving distance D, and thus the application amount Qt varies. . The problem of the conventional method described in the section of "Problems to be solved by the invention" is caused by this. The present invention is intended for a substrate having a large number of application points having different moving distances D as shown in FIG. 2 and realizing the application of the bond 1 at a high speed and with a stable application amount Qt. , Ie, the timing of opening the pressurizing valve 47, is set by a method different from the conventional method. As is clear from the graph of FIG.
The adhesion amount Q of the bond 1 adhering to the lower end of the nozzle 16a is:
It is uniquely determined by the time from the timing t0 at which the discharge of the bond 1 is started. In other words, if a certain adhesion amount Q is specified, the time from the timing t0 corresponding to the adhesion amount Q is determined. That is, the adhesion amount Q is the desired application adhesion amount Q
The timing to become e is uniquely determined by the time from the timing t0. To find this time,
First, a point P of the adhesion amount corresponding to a desired value of the adhesion amount Qe at the time of application is obtained on the graph of FIG. 5C, and then a time (time from the timing t0) Ta corresponding to this point P is obtained from the graph. . In other words, by starting the discharge of the bond 1 at a timing retroactive to the time Ta from the timing of performing the application to each application point, it is possible to obtain a desired adhesion amount Qe during the application. Therefore, from the application timing of each application point determined based on the position data of each application point on the substrate 20, the same predetermined time (Ta) is set in advance.
If the timing in the control sequence of the coating operation is set so that the pressurizing valve 47 is opened and the application of the gas pressure to the syringe 16 is started at the retrospective timing, the coating applied amount Qe is constant for each coating point. . Hereinafter, a specific application operation will be described with reference to FIG. In FIG. 6, (a) shows a syringe 16
Speed pattern in the horizontal direction (XY direction) of the nozzle 16a
4B is a timing chart showing the vertical movement (Z direction) speed pattern and the opening / closing timing of the pressurizing valve 47. FIG.
6A shows the state of the bond 1 adhering to the lower end of 6a at each timing, and FIG. 7C is a graph showing a temporal change in the amount Q of the bond 1 adhered. First, at timing t0, the moving speed in the XY directions rises, reaches the highest speed at timing t1, and thereafter moves at a constant speed between t1 and t2. Thereafter, the motor decelerates and stops at timing t3. That is, syringe 1
6 reaches the application point at this timing t3. Next, at or before this timing t3, the Z-axis motor Mz starts driving, and the nozzle 16a starts descending. Next, at timing t
At 5 (application timing), the nozzle 16a applies the bond 1 that has reached the bottom dead center of the lowering operation and adheres to the lower end portion to the surface of the substrate 20 (see FIGS. 6B and 6E). At this application timing t5, the amount of the bond 1 is the above-mentioned adhesion amount Q at the time of application.
In order to keep the applied adhesion amount Qe constant, the same predetermined time T
The pressure valve 47 should be opened at the timing t7, which has been traced back. When the discharge of the bond 1 is started from the lower end of the nozzle 16a at this timing t7 (FIG. 6 (b) (a)).
, An arrow A indicated by a broken line), the adhesion amount Q gradually increases with the progress of pressurization, reaches the maximum amount Qm at a timing t8, and then decreases by returning. At the time t5 when the time Ta has elapsed from the start of the ejection (at the time of applying the bond 1 shown in FIG. 6B and FIG. 6E), the applied amount Qe at the time of application is the same for all application points. Therefore, it is constant for all application points. Therefore, the bond 1 having a uniform application amount Qt is always applied to the substrate 20 (see (f) of FIG. 6B). As shown in FIG. 6C, as a result of the application of the bond 1 to the substrate 20, the amount of adhesion Q decreases by the amount of application Qt at timing t5, and thereafter during the return time Tw (t8 to t9). Decreases. Note that a graph q ′ indicated by a chain line after the timing t5 shows a temporal change of the adhesion amount Q when the coating is not performed. In the above description, the graph of FIG. 5C is used for describing the method of obtaining the time Ta.
It is not particularly necessary to create a graph as shown in FIG. 5C when deciding the timing of starting the discharge on the actual control program. In short, the application amount Qe at the time of application may be constant at each application point on the substrate by starting the discharge of the bond 1 at a timing retroactive to the same predetermined time Ta from the application timing. The absolute amount of the applied amount Qe at the time of application may be adjusted while observing the applied amount Qt in the actual application result while adjusting other factors such as the magnitude of the gas pressure and the pressurizing time Td. As described above, at many application points on the substrate where the moving distance D of the syringe 16 is different, the nozzle 16 is moved down from the timing at which the gas pressure is applied to the syringe and the discharge of the bond 1 is started. By setting the time Ta until the timing of applying 1 to the substrate to the same predetermined time for each application point, a uniform application amount can always be obtained. According to the present invention, the time from when the application of gas pressure for causing the syringe to perform the discharging operation to the time when the bond discharged at the lower end of the nozzle is applied to the substrate is started. Is set to the same predetermined time predetermined for each application point, so that the amount of the bond attached to the lower end of the nozzle at the timing of applying the bond to the substrate can be made constant. By a simple method of setting the drive timing, a stable bond application with a uniform application amount can always be performed. Further, since the bond amount after the bond is discharged from the nozzle is not stable, the nozzle can be landed on the substrate during the return time of the bond and the bond can be applied, so that the application interval can be shortened. Tact time is reduced. As a result, it is possible to apply a bond at a high speed and with a stable application amount, which was impossible in the past.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a bond applying apparatus according to one embodiment of the present invention. FIG. 2 is a substrate showing a bond applying mode by a bond applying apparatus according to one embodiment of the present invention. FIG. 3 is a block diagram of a control system of a bond applying apparatus according to an embodiment of the present invention. FIG. 4 (a) is an enlarged view of a nozzle of a bond applying apparatus according to an embodiment of the present invention ( b) Enlarged view of the nozzle of the bond applying apparatus according to one embodiment of the present invention. (c) Enlarged view of the nozzle of the bond applying apparatus according to one embodiment of the present invention. (B) Enlarged view of a nozzle of the bond applying apparatus according to an embodiment of the present invention (c) Enlarged view of a nozzle of the bond applying apparatus according to an embodiment of the present invention (c) FIG. 6 is a graph showing the amount of adhered bond at the lower end of the nozzle. Timing chart of the nozzle applying operation of the bond applying apparatus of the embodiment (b) Enlarged view of the nozzle of the bond applying apparatus of the embodiment of the present invention (c) Application of the bond of the embodiment of the present invention Graph showing the amount of bond attached to the lower end of the nozzle of the apparatus [Description of symbols] 1 Bond 10 Camera 11 X table 12 Y table 16 Dispenser 16a Nozzle 19a Guide rail 19b Guide rail 19c Clamper 20 Substrate 31 Feeding reel 32 Take-up reel 33 Tape 40 Main control unit 41 Application data storage unit 42 Application condition storage unit 43 Application condition adjustment data storage unit 44 Recognition unit

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-192626 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05K 3/34 B05C 5/00

Claims (1)

(57) [Claims 1] A bond is discharged to a lower end portion of a nozzle by applying gas pressure to a bond in a syringe while horizontally moving the syringe relative to a substrate. A method of applying a bond for bonding electronic components, wherein a bond attached to a lower end of a nozzle is applied to a plurality of application points on a substrate having different distances between application points by landing. Applying the gas pressure at a timing retroactive to the same predetermined time preset for all application points from each application timing determined based on the position data of the electronic component bonding bond. Method.