JPH0528764Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an improvement in capillary positioning means in a wire bonding device.

(Prior Art) When performing wire bonding, it is necessary to position the capillary so that the wire is accurately bonded to each bonding position on the set chip. DESCRIPTION OF THE PREFERRED EMBODIMENTS Capillary positioning means of a conventional wire bonding apparatus will be described below with reference to the drawings.

Fig. 3 is a diagram showing the positional relationship between the bonding position and the capillary, and a in the figure is a longitudinal cross-sectional view of the capillary, 7 is the capillary, 21 is the center axis of the capillary, 22 is the tip of the capillary, and 8 is the wire. shows. At the first bonding position, the wire 8 is welded to the pad at the center of the capillary 7, but at the second and subsequent (n+1)th (n≧1) bonding positions, the wire 8 is welded to the outside of the capillary 7. Since the wire 8 is welded to the pad at a certain n-th bonding position, the wire 8 is press-welded to the pad at the capillary tip 22 which is spaced from the capillary center axis 21 by the capillary tip radius r.

3b shows the positional relationship between the bonding position and the capillary in the bonding plane,
10 is the nth (n≧1) bonding position;
31 is the n+1-th bonding position, 35 is the capillary center position corresponding to the n+1-th bonding position 31, and the capillary center position 35 corresponding to the n+1-th bonding position 31 is the n-th bonding position 10. n+
The n+1st bonding position 3 is located on the extension of the straight line connecting the first bonding position 31.
1 by the capillary tip radius r. Therefore, there is a distance x between the capillary center and the capillary tip between the coordinates of the capillary center position 35 corresponding to the n+1th bonding position 31 and the coordinates of the n+1th bonding position 31.
A deviation dx in the direction and a deviation dy in the y direction between the center of the capillary and the tip of the capillary occur.

The capillary position calculation circuit is inputted in advance with the coordinates of the capillary center position 35 having the above-mentioned deviation from the coordinates of the n+1th bonding position 31, and upon alignment, calculates the coordinates of the n+1th bonding position 31. When it is known that the coordinates of the bonding position of the set chip are different from the coordinates of the bonding position of the set chip, the coordinates of the bonding position of the set chip are The coordinates of the capillary center position 35 corresponding to the (n+1)th bonding position 31 are corrected and output as a capillary position signal. The above modification will be explained as follows using the drawings.

FIG. 2 is a diagram illustrating the process of correcting the capillary center position according to the embodiment of the present invention, in which the conventional process of correcting the capillary center position is also shown using broken lines. In the figure, 10 indicates the n-th bonding position, 11 indicates the n+1-th bonding position at the time of input, and 15 indicates the capillary center position corresponding to the n+1-th bonding position 11 at the time of input. The capillary position calculation circuit receives an input calculated from the coordinates of the (n+1)th bonding position 11, the coordinates of the nth bonding position 10, and the tip radius r of the capillary at the time of input, which are determined based on the type of chip to be bonded. The coordinates of the capillary center position 15 corresponding to the (n+1)th bonding position 11 at the time are input in advance at the start of bonding. When the chip to be bonded is set by starting bonding, alignment is performed, and the coordinates of the (n+1)th bonding position 12 after alignment are determined. The n+1st bonding position 12 after this alignment
is rarely on a straight line passing through the n-th bonding position 10 and the n+1-th bonding position 11 at the time of input, and the n+1-th bonding position 12 after alignment other than on this straight line
On the other hand, the capillary calculation circuit calculates the capillary center position 15 corresponding to the n+1-th bonding position 11 at the time of input and the n+1-th bonding position after alignment.
With respect to the midpoint of the line segment connecting the bonding position 12 with the bonding position 12, the coordinates of a position that is almost point symmetrical with the n+1 bonding position 11 at the time of input are calculated and set as the coordinates of the corrected capillary center position 17. Output as a signal.

The capillary position control circuit that has received the capillary position signal corrects the center of the capillary based on the capillary position signal and sets the capillary center position 1.
Position at 7.

(Problems to be Solved by the Invention) However, the capillary positioning means of the conventional wire bonding apparatus described above directs the wire from the n-th bonding position 10 to the corrected capillary center position 17, as shown in FIG. Since the n+1th modified bonding position 18 is a circle whose center is the modified capillary center position 17 and whose radius is the tip radius r of the capillary, and from the nth bonding position 10 to the modified capillary center. This is the intersection with the straight line drawn toward position 17.

Furthermore, as described above, the capillary center position 15 corresponding to the n+1-th bonding position 11 at the time of input is on the extension of the straight line connecting the n-th bonding position 10 and the n+1-th bonding position 11 at the time of input. , a straight line connecting the n+1-th bonding position 11 at the time of input and the n+1-th bonding position 12 after alignment, and the capillary center position 15 and corrected capillary center position 17 corresponding to the n+1-th bonding position at the time of input. Since the straight line connecting them is almost parallel and can be considered to be of equal length, the straight line connecting the corrected capillary center position 17 and the n-th bonding position 10 is the line connecting the n+1-th bonding position 12 and the It never coincides with the straight line connecting the n-th bonding position 10. Therefore, the above-mentioned n+
It is impossible for the first modified bonding position 18 to coincide with the (n+1)th bonding position 12 after alignment. That is, the capillary positioning means of the conventional wire bonding apparatus inputs the coordinates of the capillary center position instead of the coordinates of the bonding position, and positions the capillary based on the capillary position signal corrected based on the alignment. There is a problem in that the capillary is not positioned so that subsequent bonding can be performed accurately at the bonding position of the set chip.

The purpose of this invention is to input the coordinates of the bonding position itself instead of the coordinates of the capillary center position, replace these with the coordinates of the bonding position obtained by alignment, and correspond to the coordinates of the bonding position after the replacement. By having a capillary position calculation circuit that calculates the capillary center position and outputs it as a capillary position signal, and a capillary position control circuit that receives the capillary position signal and positions the capillary based on the capillary position signal,
It is an object of the present invention to provide a wire bonding device that can accurately perform bonding from the second point onwards at the bonding position of the set chip.

(Means for solving the problems) The present invention has the following means configuration to achieve the above object. That is, the wire bonding apparatus of the present invention replaces the bonding position input in advance with the bonding position obtained by alignment, and determines the capillary center position corresponding to the replaced bonding position. A wire bonding device comprising: a capillary position calculation circuit that calculates and outputs the calculated result as a capillary position signal; and a capillary position control circuit that receives the capillary position signal and positions the capillary based on the capillary position signal. It is.

(Operation) The operation of the wire bonding apparatus of the present invention having the above-described means will be explained below.

The wire bonding device of the present invention has a capillary position calculation circuit and a capillary position control circuit, and the capillary position calculation circuit is inputted in advance with the coordinates of the bonding position based on the type of chip to be bonded. Therefore, if it is known that there is a discrepancy between the coordinates of the bonding position and the bonding position of the set chip, the bonding position obtained by aligning the coordinates of the bonding position entered in advance can be used. The coordinates of the capillary center position corresponding to the coordinates of the replaced bonding position are calculated based on the coordinates of the replaced bonding position and the tip radius of the capillary, and these are output as a capillary position signal.

Upon receiving the capillary position signal, the capillary position control circuit moves the capillary according to the capillary position signal, so that the tip of the capillary is placed at a position where the wire can be pressed against the pad and welded at the bonding position after alignment. Position.

As explained above, the capillary position calculation circuit included in the wire bonding apparatus of the present invention is inputted in advance with the coordinates of the bonding position itself, not the coordinates of the capillary center position, and these are used to calculate the bonding position obtained by alignment. The capillary center position corresponding to the replaced coordinates of the bonding position is calculated and output as a capillary position signal. The capillary position control circuit installed alongside the capillary calculation circuit receives the capillary position signal and positions the capillary based on the signal, so the wire bonding apparatus of the present invention can also be used for bonding positions after the second point. Bonding can be performed at precise positions that could not be performed with conventional wire bonding equipment.

(Embodiment) A wire bonding apparatus according to an embodiment of the present invention will be described below based on the drawings. FIG. 1 is a block diagram of a capillary positioning means of a wire bonding apparatus according to an embodiment of the present invention, and FIG. 2 is a diagram illustrating a capillary center position correction process according to an embodiment of the present invention.

In Fig. 1, 1 is an alignment circuit, 2 is an actual bonding position signal, 3 is a capillary position calculation circuit, 4 is a capillary position signal, 5 is a capillary position control circuit, 6 is a capillary drive signal, 7 is a capillary, and 7a is a capillary 7 is a drive unit, and 8 is a wire.

The capillary position calculation circuit 3 determines the n-th position shown in FIG. 2 based on the type of chip to be bonded.
Bonding position 10 (n≧1), n+
Each coordinate of the first bonding position 11 is input in advance. When alignment is performed at the start of bonding, alignment circuit 1 detects the (n+1)th bonding position 12 after alignment and sends its coordinates as actual bonding position signal 2 to capillary position calculation circuit 3. The capillary position arithmetic circuit 3 that has received the actual bonding position signal 2 replaces the coordinates of the n+1st bonding position 11 at the time of input with the coordinates of the n+1th bonding position 12 after alignment, and calculates the coordinates and the nth The coordinates of the capillary center position 16 corresponding to the (n+1)th bonding position 12 after alignment are calculated from the coordinates of the th bonding position 10 and the tip radius r of the capillary, and are output as the capillary position signal 4. The capillary position control circuit 5 receives the capillary position signal 4, and
A capillary drive signal 6 corresponding to the capillary position signal 4 is sent to the drive section 7a of the capillary 7.

The capillary 7 moves in accordance with the capillary drive signal 6 to align its center position with the capillary center position 16 corresponding to the (n+1)th bonding position 12 after alignment, and aligns from the nth bonding position 10. later n+1
Pulling the wire 8 toward the capillary center position 16 corresponding to the second bonding position 12,
This is pressed against the pad at the tip of the capillary located at the (n+1)th bonding position 12 after alignment and welded.

(Effects of the invention) As explained above, the capillary position calculation circuit included in the wire bonding apparatus of the present invention is inputted in advance with the coordinates of the bonding position itself, not the coordinates of the capillary center position, and can be obtained by matching the coordinates of the bonding position itself. The capillary center position corresponding to the replaced bonding position coordinates is calculated and output as a capillary position signal. The capillary position control circuit installed alongside the capillary calculation circuit receives the capillary position signal and positions the capillary based on the signal, so the wire bonding apparatus of the present invention can also be used for bonding positions after the second point. It has the advantage of being able to perform bonding at a precise position, which was not possible with conventional wire bonding equipment.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the capillary positioning means of the wire bonding apparatus according to the embodiment of the present invention, Fig. 2 is a diagram illustrating the capillary center position correction process according to the embodiment of the present invention, and Fig. 3 is the position of the bonding position and the capillary. It is a figure showing a relationship. 1... Alignment circuit, 2... Actual bonding position signal, 3... Capillary position calculation circuit, 4...
Capillary position signal, 5... Capillary position control circuit, 6... Capillary drive signal, 7... Capillary, 7a... Drive section, 8... Wire, 10...
nth bonding position, 11... n+1st bonding position at the time of input, 12... n+1th bonding position after alignment, 15
... n+1st bonding position 1 at the time of input
16...Capillary center position corresponding to the n+1st bonding position 12 after alignment, 17...Corrected capillary center position, 18...N+1th corrected bonding position, 21... ...center axis of the capillary,
22... Capillary tip, 31... n+1st bonding position, 35... Capillary center position corresponding to n+1th bonding position 31, dx... Displacement in the x direction between the capillary center and the capillary tip, dy... ...Displacement in the y direction between the capillary center and the capillary tip, r...Capillary tip radius.

Claims (1)

[Scope of utility model registration request] In the wire bonding device, the bonding position input in advance is replaced with the bonding position obtained by alignment, the capillary center position corresponding to the replaced bonding position is calculated, and this is output as a capillary position signal. a capillary position calculation circuit that receives the capillary position signal and positions the capillary based on the capillary position signal;
A wire bonding device comprising: