JP3385941B2 - Thermocompression bonding apparatus and thermocompression bonding method for electronic components - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component thermocompression bonding apparatus and a thermocompression bonding method for thermocompression bonding an electronic component to a substrate.

[0002]

2. Description of the Related Art As a method for bonding an electronic component to a substrate, a method using thermocompression bonding is known. In this method, an electronic component is held by a thermocompression bonding tool and pressed against the surface of the substrate, and the electronic component is heated to bond the electronic component to the substrate by soldering or a resin adhesive. In order to obtain good thermocompression bonding quality, control target values such as the temperature of the electronic components during the thermocompression bonding process and the crimping load that presses the electronic components against the board are controlled according to a predetermined temporal change pattern, that is, a command profile. There is a need to.

[0003]

By the way, the degree of difficulty of thermocompression bonding of electronic components is not constant, but varies depending on the type and application of the electronic component. Generally, thermocompression bonding is very difficult,
That is, in the case of an electronic component that requires good crimp quality, more strict temperature control is required. On the contrary, strict temperature control is not required for the thermocompression bonding which is not so important and the thermocompression bonding is difficult.

However, in the conventional thermocompression bonding apparatus for electronic parts, the thermocompression bonding operation is performed in the same pattern regardless of the degree of difficulty of thermocompression bonding. For this reason, if the degree of difficulty is high, the crimping quality may be poor, whereas if the degree of difficulty is low, the thermocompression bonding time may be unnecessarily lengthened and the takt time may be increased. However, there is a problem that appropriate thermocompression bonding conditions are not applied as needed.

Therefore, an object of the present invention is to provide a thermocompression bonding apparatus and a thermocompression bonding method for electronic parts, which can perform proper thermocompression bonding as needed.

[0006]

A thermocompression bonding apparatus for an electronic component according to claim 1, wherein a thermocompression bonding tool for thermocompression bonding the electronic component, an elevating means for elevating the thermocompression bonding tool, and the thermocompression bonding tool are used. a heater for heating the electronic components Te, a lift control means for controlling the vertical movement of the thermocompression bonding tool, a temperature control unit for controlling the temperature of the heater, the thermocompression
Divided into a plurality of steps, heat <br/> compression based on the target motion pattern of the plurality of the target values storage section for storing control target value, the thermocompression bonding operation that combines the plurality of the control target value for each step Multiple executions of different operation programs that cause operations
An operation program storage unit that stores the data according to the mode ,
Set the execution mode for the actual thermocompression bonding operation.
And a mode setting storage unit for storing the mode setting information.
Operation program corresponding to the execution mode set in the memory
The elevation control means and the temperature control section according to
It

A thermocompression bonding method for an electronic component according to claim 4 is
A thermocompression bonding tool for thermocompression bonding of electronic components and this thermocompression bonding tool.
Via the thermo-compression tool
Heater for heating electronic parts and lifting / lowering of the thermocompression bonding tool
Elevation control means for controlling the operation and the temperature of the heater are controlled.
Controlled temperature controller and thermocompression bonding process are divided into multiple steps.
A target that divides and stores multiple control target values for each step
Value storage unit and thermocompression bonding that combines the control target values
Perform thermocompression bonding operation based on the target operation pattern of the work
Make the operating program compatible with different execution modes
Thermo-compression of electronic parts with operation program storage section to store
A method for thermocompression bonding of electronic components in
Set the execution mode to perform thermocompression bonding operation in advance
It is stored in the setting storage section, and when thermocompression bonding, the mode
The operation program corresponding to the execution mode stored in the setting storage
And to control the thermocompression bonding operation by the ram.

According to the invention described in each claim, the execution mode for actually performing the thermocompression bonding operation based on the target operation pattern of the thermocompression bonding operation in which the control target value of the thermocompression bonding operation is combined It is set and stored in advance according to the degree of difficulty, and at the time of thermocompression bonding, by controlling the thermocompression bonding operation based on the target operation pattern according to the execution mode of the thermocompression bonding operation selected from the execution modes, the same Based on the target operation pattern, it is possible to apply appropriate thermocompression bonding conditions according to the needs of the target electronic component.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a thermocompression bonding apparatus for electronic parts according to an embodiment of the present invention, FIG. 2 is a display screen diagram of the thermocompression bonding apparatus for electronic parts, and FIGS. 6 is a graph showing an example of controlling the thermocompression bonding device for components.
7, 8, 9, and 10 are flow charts for explaining the operation of the thermocompression bonding apparatus for electronic components.

First, the structure of a thermocompression bonding apparatus for electronic components will be described with reference to FIG. In FIG. 1, the positioning table 1
The substrate 2 is placed on the top. An electrode 2a is provided on the substrate 2, and an electronic component 3 is provided on the electrode 2a with a bump 3a.
Is installed through. The electronic component 3 is a crimping head 5
It is adsorbed and held by the thermocompression bonding tool 4 mounted on the. A heater 6 is built in the pressure bonding head 5, and the heater 6 heats the electronic component 3 via the thermocompression bonding tool 4.
Further, the thermocompression bonding tool 4 is provided with a temperature sensor 7, and the temperature sensor 7 detects the temperature of the thermocompression bonding tool 4 heated by the heater 6.

The thermocompression bonding head 5 is mounted on a Z-axis table 8 as an elevating means. The Z-axis table 8 includes a nut 11, a feed screw 10 and a Z-axis motor 9,
By driving the Z-axis motor 9, the pressure bonding head 5 moves up and down. The crimping head 5 is provided with a load cell 12, and the load cell 12 measures the pressing force when the Z-axis table 8 is driven to press the electronic component 3 against the substrate 2, that is, the crimping load of the electronic component 3.

The pressure load signal detected by the load cell 12 is A / D converted by the A / D converter 13 and transmitted to the controller 20. The power supply unit 14 supplies heating power for the heater 6. The A / D converter 17 A / D converts the temperature (a) detected by the temperature sensor 7 into a feedback temperature signal (b), which is sent to the deviation calculator 16. The PID control unit 15 has a command temperature (c) commanded from the control unit 20,
Based on the deviation of the feedback signal from the temperature sensor 7 obtained by the deviation calculation unit 16, the control operation amount (d) is output to the power feeding unit 14. That is, the power feeding unit 14, the PID control unit 15, and the deviation calculation unit 16 form a temperature control unit.

The timer 18 counts the sampling time, receives the start signal (e) from the controller 20, and outputs the time-up signal (f) after a predetermined time. The Z-axis controller 19 controls driving of the Z-axis table 8. Therefore,
The Z-axis control unit 19 serves as an elevating control unit that controls elevating the thermocompression bonding tool 4. The control unit 20 also includes three storage units, a target value storage unit 21, a mode setting storage unit 22, and an operation program storage unit 23. The target value storage unit 21 stores control target values such as the target time, the target temperature, and the Z-axis control target value input from the keyboard 25.

The mode setting storage unit 22 sets and stores the execution mode when the actual thermocompression bonding operation is performed. Here, the execution mode represents a mode of execution when the actual thermocompression bonding operation is performed based on the target operation pattern of thermocompression bonding in which the control target values are combined. That is, even if the target operation pattern is the same, if the execution mode is different, the execution result differs because the control target value to be prioritized in the process of thermocompression bonding is different. Become. As will be described later, the execution modes include an execution mode that prioritizes productivity and an execution mode that prioritizes thermocompression bonding quality. In the productivity priority execution mode, the overall target time set in the target operation pattern is prioritized to strictly adhere to the takt time, and in the mode that prioritizes thermocompression bonding quality, control target values such as heating temperature and crimping load take precedence. To be done.

The operation program storage unit 23 stores a sequence program of a flow of thermocompression bonding operation. That is, the operation program for controlling the actual thermocompression bonding operation based on the target operation pattern is stored according to the set execution mode. The monitor 24 is a display means such as a CRT, and displays a set target operation pattern of thermocompression bonding, that is, a combination of control target values such as a bonding temperature and a bonding load (or a bonding height) on the same screen of the display unit. . The keyboard 25 is an input means for inputting data such as control target values and command input during operation.

Next, a control target value used in the thermocompression bonding process of electronic parts, a target operation pattern which is a combination of these, and a display screen for displaying the target operation pattern will be described with reference to FIG. In FIG. 2, a display frame 31 in the display screen 30 displays the mode number of the execution mode selected and input from the keyboard 25. The step number 32 displayed in the table frame A of the display screen 30 is
In each of the thermocompression bonding processes divided into a plurality, [0],
It is a number such as [1], [2], ....
The target time 33 is the duration t [0] of each step,
t [1], t [2], ... Similarly, the target temperature 34 is the heating target temperature T [0], T [1], T [2], ... Of the thermocompression bonding tool 4 in each step.

The target height 35 and the target load 36 are Z
These are axis control target values, each of which has the meaning described below. The target height 35 represents the degree of pressing strength of the electronic component 3 pressed against the substrate 2 by the feed amount of the Z-axis table 8 downward. Therefore, the lower the target height value, the more strongly the thermocompression bonding tool 4 is pressed against the electronic component 3 by the Z-axis table 8.
However, the displayed numerical value of the target height does not directly represent the actual height position of the thermocompression bonding tool 4.

The target load 36 represents a pressing load value for actually pressing the electronic component 3. When the target load value is set, the thermocompression bonding tool 4 is fed downward by the Z-axis table 8 until the load value detected by the load cell 12 reaches the set load value. Is realized. These Z-axis control target values Z [0], Z [1], Z [2], ... Are also set for each step. Note that the * mark 39 shown in FIG.
Indicates that the item is not set, that is, in FIG.
In the example of, the target load is not set. The END mark 40 indicates the end of the step, and in the example of FIG.

On the display screen 30, not only the control target values are displayed numerically in the table frame A as described above, but also the graph frame B is displayed.
The target motion pattern is displayed graphically in it. That is, here, the target temperature 37 and the Z-axis control target value (see FIG.
In the example, the target height) 38 is displayed as a step-like graph for each step. In the Z-axis control target value 38, either the target height or the target load is displayed depending on the case.

The display screen 30 is used not only for displaying the target operation pattern but also for setting the control target value on the display screen 30. That is, in setting the control target value in each step of the thermocompression bonding process, the control target value can be entered while visually checking the mutual relationship such as the heating temperature and the crimping load, so that the setting work becomes easy and An appropriate control target value can be set.

The thermocompression bonding apparatus for electronic parts is constructed as described above. Next, an example of control of the thermocompression bonding operation by this thermocompression bonding apparatus will be described with reference to the drawings. Here, each mode of the thermocompression bonding operation and the operation program for each mode are also stored in the mode setting storage unit 22 and the operation program storage unit 23, and all the control target values shown in FIG. It is stored in the section 21.

First, the execution mode (control example 1) of the thermocompression bonding operation which gives priority to productivity will be described with reference to FIGS. 3 and 6. First, the execution mode of the thermocompression bonding operation with priority on productivity is selected according to the electronic component 3 that is the object of the thermocompression bonding, and the operation program corresponding to this execution mode is read into the control unit 20. Before the operation shown in the flow of FIG. 6 is started, the substrate 2 is placed on the positioning table 1 shown in FIG. 1, alignment is performed, and the Z-axis table 8 is lowered.

After that, the process moves to the flow of FIG. 6, and at STEP [0] shown in FIG. 3, the Z-axis table 8 is moved to the position of Z [0],
That is, it is moved to the target height at the start of thermocompression bonding (the height at which the bump 3a of the electronic component 3 contacts the electrode 2a) Z [0] (ST1). Next, reset the timer (ST2),
The heating temperature of the thermocompression bonding tool 4 is the target temperature T [STEP]
(T [0] in this case) is set (ST3). Then, the temperature controller controls the temperature of the thermocompression bonding tool 4 to be the target temperature T [STEP].

Next, the timer 18 waits until the sampling time is up (ST4), and when the time is up, the sampling time tsamp is added to the timer (ST5). Here, the counted time t is t [ST
EP] (in this case t [0]) is determined (ST6). That is, in ST4 to ST6, it is determined whether the time of STEP has reached t [STEP].

If not exceeded, the process returns to ST4, and if exceeded, 1 is added to STEP (ST
7) Then, it is determined whether or not the STEP at that time is the final STEP. In this case, since it is STEP [1], it is determined as "NO" instead of the final STEP (that is, STEP [4]), and the Z-axis table 8 is driven to move to the target height Z [1] ( ST9). After that, the final S
The same flow is repeated until TEP [3] is reached, and the thermocompression bonding process is completed by the time up of the step time t [3] of the final STEP. In this thermocompression bonding execution mode, since the STEP progresses according to the command profile regardless of the actual temperature of the thermocompression bonding tool 4, it is possible to reliably maintain a predetermined takt time, and therefore to give priority to productivity. It is in mode.

Next, the execution mode (control example 2) of thermocompression bonding in which the quality of thermocompression bonding is prioritized will be described with reference to FIGS. 4, 7, and 8. First, as in the case of control example 1, STEP
The Z-axis table 8 is driven at [0] to move to the position of Z [0],
That is, it is moved to the target height Z [0] at the start of thermocompression bonding (ST11). Then reset the timer and press Z
The flag for setting the axis movable time is set to 0 (ST1
2). This flag is set to either 0 or 1, and only when the flag is 0, it is possible to shift to the next Z-axis control target value.

Next, the flag is confirmed (ST1
3) However, since the flag is 0 in this case, the process proceeds to ST14, where the heating temperature of the thermocompression bonding tool 4 is set to the target temperature T.
Set to [STEP] (T [0] in this case). Next, the temperature sensor 7 detects the current temperature of the thermocompression bonding tool 4 (ST15), and it is determined whether the actual temperature of the thermocompression bonding tool 4 has reached the target temperature T [0] (ST16).

If the target temperature T [0] is reached, it is determined whether STEP is [0] (ST).
17) is STEP [0] here, so ST1
Jump over 8 and proceed to ST19, where the flag is set to 1. When STEP further progresses and the flow is repeated, the Z-axis table 8 is driven in ST18 to move the Z-axis control target value Z [STEP] to the next, and then the flag is set to 1. Next, the timer 18 waits until the sampling time is up (ST20), and when the time is up, the timer is switched to the sampling time tsam
Add p.

Here, the counted time t is t [ST
EP] (t [0] in this case) or more is determined (ST22), and if t [0] is not reached, ST is determined.
Return to 13. In this case, since the flag is set to 1 in ST19, the process directly goes to ST20. If the time t is t [0] or more, 1 is added to STEP (ST23). Next, the STEP at that point is the final ST
It is determined whether or not it is EP (ST24). In this case, since it is STEP [1], it is not the final STEP.
It is judged "NO", and the process returns to ST12. Then, the flag is set to 0 again, the time counting counter is reset, the same flow is repeated, and the step time t of the final STEP is t.
The thermocompression bonding process is completed by the time up of [3].

In the execution mode of this control example 2, the Z-axis table 8 is driven until the temperature of the thermocompression bonding tool 4 reaches the target temperature, and the Z-axis control target value is shifted to the next Z-axis control target value. Therefore (ST16 and ST18), the combination of the predetermined target temperature and the Z-axis target value is maintained, and therefore, the mode is prioritized to maintain the quality of thermocompression bonding.

Next, an execution mode in which the thermocompression bonding quality is given the highest priority will be described with reference to FIGS. 5, 9 and 10. First, in the same manner as in the control example 2, the Z-axis table 8 is set in STEP [0].
Drive the Z [0] position, that is, Z at the start of thermocompression bonding.
It is moved to the axis control target value Z [0] (ST31). Next, the timer is reset and the flag is set to 0 as in the control example 2 (ST32). Next, the flag is confirmed (ST33), and here the heating time of the thermocompression bonding tool 4 is set to the target temperature T [STEP] (here, T [0]). Next, the temperature sensor 7 detects the current temperature of the thermocompression bonding tool 4 (ST35), and it is determined whether the actual temperature of the thermocompression bonding tool 4 has reached the target temperature T [0] (ST36).

If the target temperature T [0] is reached, the next STEP is [0], so the program skips ST38, proceeds to ST39, and sets the flag to 1. In addition, STE
When P advances and the flow is repeated, ST38
Drive the Z-axis table 8 to drive the Z-axis control target value Z [ST
EP] to the next and then set the flag to 1.

When the temperature of the thermocompression bonding tool 4 has not reached the target temperature T [0] in ST36 and after the flag is set to 1 in ST39, the counted time t
Is greater than or equal to t [STEP] (here, t [0]) (ST42), and if t is less than t [STEP], the process returns to ST33. At this time, if the temperature of the thermocompression bonding tool 4 has reached the target temperature T [0] in ST36, the flag is set to 1 in ST39, so S
At T33, the process directly proceeds to ST40, and waits for the sampling time of the timer 18 to increase (ST4
0), when the time is up, the sampling time tsamp is added to the timer. If the target temperature T [0] is not reached in ST36, the flag is set to 0 and the process returns to ST33.
Until [0] is reached (ST34 to ST36 to ST42
~ ST33) is repeated.

Then, at ST42, the time t is t [STE
P] (here, t [0]) or more, STEP
Is incremented by 1 (ST43). Next STE at that time
It is determined whether P is the final step (ST4).
4). In this case, since it is STEP [1], the final ST
It is determined to be "NO" instead of EP, and the process returns to ST32. Then, the flag is set to 0 again, the timer is reset, and the same flow is repeated until STEP [3].

In the execution mode of this control example 3, the counting of the target time of each STEP is started after the temperature of the thermocompression bonding tool 4 reaches the target temperature of each STEP, so that the predetermined target temperature and Z-axis control target In addition to the value, a predetermined target time is secured. As a result, the overall thermocompression bonding time becomes longer than the prescribed command profile, and as a result the takt time is extended, but since the prescribed control target values are all satisfied, the thermocompression bonding quality is kept good. Therefore, the control example 3 is in the execution mode in which the thermocompression bonding quality is given the highest priority.

As described above, different execution modes are set according to the electronic components to be thermocompression-bonded and stored in the mode setting storage section, so that the same target operation pattern can be obtained only by switching the execution modes. Based on the above, it is possible to apply appropriate thermocompression bonding conditions according to the needs of the target electronic component.

[0037]

According to the present invention, the execution mode for actually performing the thermocompression bonding operation is preset based on the target operation pattern of the thermocompression bonding operation, which is a combination of the control target values of the thermocompression bonding operation, and is set in the mode storage unit. It is stored and the thermocompression bonding operation is executed according to the selected execution mode during thermocompression bonding.Therefore, based on the same target operation pattern, the productivity priority execution mode It is possible to set a plurality of execution modes of thermocompression bonding operations according to different purposes, such as an execution mode in which the crimping quality has priority. Therefore, by changing only the execution mode without changing the control target values such as the target time, the heating temperature, and the pressure bonding load each time, it is possible to apply the appropriate thermocompression bonding conditions according to the needs of the target electronic component. . That is, when the thermocompression bonding is low, the productivity can be improved by giving priority to the tact time, and when the thermocompression bonding is high, the product quality can be improved by giving priority to the quality. .

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a thermocompression bonding apparatus for electronic components according to an embodiment of the present invention.

FIG. 2 is a display screen diagram of a thermocompression bonding apparatus for electronic components according to an embodiment of the present invention.

FIG. 3 is a graph showing a control example of the thermocompression bonding apparatus for electronic components according to the embodiment of the present invention.

FIG. 4 is a graph showing a control example of the thermocompression bonding apparatus for electronic components according to the embodiment of the present invention.

FIG. 5 is a graph showing a control example of the thermocompression bonding apparatus for electronic parts according to the embodiment of the present invention.

FIG. 6 is a flowchart for explaining the operation of the thermocompression bonding apparatus for electronic components according to the embodiment of the present invention.

FIG. 7 is a flowchart for explaining the operation of the thermocompression bonding apparatus for electronic components according to the embodiment of the present invention.

FIG. 8 is a flowchart illustrating the operation of the thermocompression bonding apparatus for electronic components according to the embodiment of the present invention.

FIG. 9 is a flowchart illustrating the operation of the thermocompression bonding apparatus for electronic components according to the embodiment of the present invention.

FIG. 10 is a flowchart for explaining the operation of the thermocompression bonding apparatus for electronic components according to the embodiment of the present invention.

[Explanation of symbols]

1 Positioning table 2 substrates 3 electronic components 4 Thermo-compression tool 5 Crimping head 7 Temperature sensor 8 Z-axis table 12 load cell 14 power supply 15 PID controller 19 Z-axis controller 20 Control unit 21 Target value storage 22 Mode setting storage 23 Operation Program Storage

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-252211 (JP, A) JP-A-8-279536 (JP, A) JP-A-7-303000 (JP, A) JP-A-2- 121345 (JP, A) JP 6-6072 (JP, A) JP 63-309385 (JP, A) JP 11-54904 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 21/60 H05K 3/34 H05K 13/04

Claims (6)

(57) [Claims] 1. A thermocompression bonding tool for thermocompression bonding an electronic component, an elevating means for elevating the thermocompression bonding tool, a heater for heating an electronic component via the thermocompression bonding tool, and an elevating operation of the thermocompression bonding tool. A lifting control means for controlling, a temperature control section for controlling the temperature of the heater, and a plurality of thermocompression bonding processes.
Divided into steps, operations program and a target value storage section for storing a plurality of control target values for each step to perform the thermocompression bonding operation based on the target motion pattern of the thermocompression bonding operation that combines the plurality of the control target value Different execution modes
The operation program storage unit that stores the
Set and memorize the execution mode when performing thermocompression bonding operation
And a mode setting storage unit
According to the operation program corresponding to the set execution mode
A thermocompression bonding apparatus for electronic parts, which controls the lifting control means and the temperature control section . 2. The control target value is a target time of each step.
Between, the target temperature which is the heating target temperature of the thermocompression bonding tool,
And the feed amount of the lifting means or the thermocompression tool
Z-axis control target value, which is the target load when pressing parts
If the execution mode is one that gives priority to productivity,
If the target time of the step has elapsed, the next step is controlled.
The control is performed based on a target value.
A thermocompression bonding device for the electronic component described. 3. The control target value is a target time of each step.
Between, the target temperature which is the heating target temperature of the thermocompression bonding tool,
And the feed amount of the lifting means or the thermocompression tool
Z-axis control target value, which is the target load when pressing parts
The execution mode is one in which the thermocompression bonding quality is prioritized.
In the case of, the temperature of the thermocompression bonding tool in the step is the target temperature.
After waiting until the
Characterized in that the elevating means is controlled based on a standard value.
The thermocompression bonding apparatus for electronic parts according to claim 1. 4. A thermocompression bonding tool for thermocompression bonding of electronic parts, and
Elevating means for elevating and lowering the thermocompression bonding tool, and the thermocompression bonding tool.
Heater for heating electronic components via
Lifting control means for controlling the lifting operation of the tool, and the heater
Temperature control unit that controls the temperature of the
Divide into steps and set multiple control target values for each step
A target value storage unit for storing and combining the plurality of control target values
Based on the target operation pattern of the thermocompression bonding operation
Multiple execution modes with different operating programs
With an operation program storage unit that stores the
A thermocompression bonding method of the electronic component in the thermocompression bonding device of the child component, set the execution mode when the real carry out the thermocompression bonding operation previously may be stored in the mode setting storage section, wherein the mode setting stored at the time of thermocompression bonding Corresponding to the execution mode stored in the section
A thermocompression bonding method for electronic parts, characterized in that the thermocompression bonding operation is controlled by an operation program . 5. The control target value is a target time of each step.
Between, the target temperature which is the heating target temperature of the thermocompression bonding tool,
And the feed amount of the lifting means or the thermocompression tool
Z-axis control target value, which is the target load when pressing parts
If the execution mode is one that gives priority to productivity,
If the target time of the step has elapsed, the next step is controlled.
5. The control according to the target value.
A thermocompression bonding method for the electronic component described. 6. The control target value is a target time of each step.
Between, the target temperature which is the heating target temperature of the thermocompression bonding tool,
And the feed amount of the lifting means or the thermocompression tool
Z-axis control target value, which is the target load when pressing parts
The execution mode is one in which the thermocompression bonding quality is prioritized.
In case of, the temperature of the thermocompression bonding tool in the step is the target temperature.
After waiting until the
Characterized in that the elevating means is controlled based on a standard value.
The thermocompression bonding method for an electronic component according to claim 4.