JPH038351A - Wire bonding method - Google Patents

Abstract

PURPOSE:To improve work efficiency of bonding and to enable high quality of bonding by performing the recognition and memory works of the positions of all leads to be bonded next during wire bonding work. CONSTITUTION:Individual position coordinates of leads are sought based on the coordinate standard of a lead position at the position of a prestage 15 one pitch on this side of a bonding stage 14. That is, a lead position recognition camera 17, which is fixed to an X-Y table 16 being placed on an X-Y table 11 and performing horizontal shift different from the X-Y table 11, catches detection marks 6-1 and 6-2, being the coordinates of the leads 4, by the X-Y table 16 being operated according to the distance of the standard position of the lead 4 stored in a recognition storage device 18, and it recognizes the position coordinate of the lead 4 and stores it in the recognition storage device 18. Next, by shifting a table 10 pitch by pitch and shifting a table 11 according to the coordinate of the standard position of a pad 3 being stored, wire bonding is done by a bonding tool 12.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention aims to shorten the overall bonding time by overlapping bonding work and bonding position detection in wire bonding work in an IC & The present invention relates to a wire bonding method that can improve performance.

[Conventional technology]

The detailed structure of the bonding sample before wire bonding in IC assembly is, for example, as shown in FIG.
Leads 4 for bonding connection by wires 5 (see FIG. 5) are formed on the lead frame 1 corresponding to the pads 3 of the C element 2. Reference numerals 6-1 and 6-2 are detection marks that serve as coordinate reference points for the lead position, and usually one or two locations are required, and the tip of the lead 4 can also serve as a detection mark. FIG. 4 shows a part of a frame, ie, a lead frame 1, in which the icm vertical structure as shown in the first figure is arranged continuously at a certain pitch.

In addition, FIGS. 5 and 6 show wires 5 in IC assembly.
The detailed configuration after bonding is shown.

By the way, in this type of wire bonding work, a recognition camera fixed to an XY child table which is provided with a bonding head and moves horizontally is connected to the IC element 2. The positional coordinates of the pad 3 and lead 4 are recognized and memorized by being moved directly above the lead 4, and then wire bonding is performed while the bonding head is moved based on the memorized positional coordinates.

[Problem to be solved by the invention]

However, in such conventional wire bonding work, it is not possible to perform lead position recognition work and bonding work at the same time. Especially when bonding multiple pins such as lead frames, ceramic packages, carrier boards, etc., the lead position cannot be recognized at the same time. In many cases, there are individual deviations, and the lead position! The lead position recognition work significantly impedes bonding workability and makes it difficult to improve productivity.

The present invention eliminates the above-mentioned conventional drawbacks, improves bonding workability by overlapping lead position recognition work and wire bonding work, and improves productivity.
Furthermore, it is an object of the present invention to provide a wire bonding method that enables high-quality bonding.

[Means to solve the problem]

The present invention provides a method for performing wire bonding by sequentially transporting bonding samples equipped with pads and leads to be bonded to a bonding position at a constant pitch, in which an XY child table at a bonding position is separated from the bonding position one pitch before the bonding position. After the lead position recognition camera fixed to the XY child table recognizes and stores the individual lead position coordinates of the bonding sample, the bonding sample is transported to the bonding position and the XY child table at that position is fixed to recognize the pad position. This wire bonding method is characterized in that the position coordinates of the pads are recognized and stored using a camera, and this and the stored lead position coordinates are read back to perform bonding.

[For production]

In the present invention, when the bonding sample is sequentially conveyed to the bonding position at a constant pitch, when the bonding sample is positioned one pitch before the bonding position, the bonding position is determined according to the coordinates of the standard position 1 of the lead stored in advance. The XY child table of is another
A lead position recognition camera fixed to the Y child table determines one or two coordinate reference points of the lead, and then based on these, the individual lead position coordinates are recognized and stored.

Next, this bonding sample is transported one pitch and placed at the bonding position, and the bonding position is
The pad position recognition camera fixed to the Y child table prompts one or two of the pad coordinate reference points, and based on that, the pad position coordinates are recognized and memorized. Read back the position coordinates of all leads and perform wire bonding.

During this bonding operation, the individual lead position coordinates of the next bonding sample being conveyed one pitch before are recognized and memorized as described above, and the aforementioned operation is repeated.

In this way, the bonding work and the lead position recognition work are performed in an overlapping manner.

(Embodiment) The embodiment of the present invention will be described with reference to the drawings.
In the figure, for example, when a lead frame as shown in FIG. 4 is used as a bonding sample 10 and is transported at a fixed pitch to a bonding stage 14 provided on an XY child table 1 and equipped with a bonding head 13 having a bonding tool 12, Bonding stage 14
The individual position coordinates of the lead 4 are determined based on the coordinate reference point of the lead position at the position of the prestage 15 one pitch before the position of the prestage 15. That is, the lead position recognition camera 17 , which is placed on the XY child table 1 and is fixed to the XY child table 6 which moves horizontally in a manner different from that of the XY child table 1 , detects the lead 4 stored in the recognition storage device 18 . By operating the XY child table 6 according to the coordinates of the standard position of
- Select one or two points of the detection marks 6-1 and 6-2 which are the coordinate reference points of the lead 4 (the tip of the lead 4 is also possible), then recognize the position coordinates of each lead 4, and use the recognition memory. 18
to be memorized.

Next, this bonding sample lO is transported one pitch and positioned on the bonding stage 14, and the XY child table 1 is operated according to the coordinates of the standard position of the pad 3 stored in the recognition storage device 18. The pad position recognition camera 19 fixed on the table 1 recognizes the position coordinates of the pad 3 by pointing to one or two coordinate reference points (or the pad 3) of the pad 3, and the recognition storage device 18
Then, the position coordinates of the pad 3 and the position coordinates of all the leads recognized and stored by the prestage 15 are read back, and wire bonding is performed by the bonding tool 12.

That is, on the bonding stage 14, all the corresponding bonding positions of the pads 3 and leads 4 of the bonding sample IO are determined, and wire bonding is performed.

During this bonding process, Prestige 1
The position coordinates of all the leads of the next bonding sample 10 being conveyed to the bonding sample 5 are recognized and stored as described above, and the bonding work and the lead position recognition work are performed in an overlapping manner.

Note that the reference positional relationship between the lead position recognition camera 17 and the bad position recognition camera 19 is based on the bonding sample 10.
Set or correct it to 1 pitch.

In FIG. 1, 20 is a base frame on which the XY child table is placed, and 21 is a TV for visual viewing.

FIG. 2 shows another embodiment of the present invention, in which the XY child table 6 of the lead position recognition camera 17 is provided directly on the base frame 20 separately and independently from the XY child table 1;
The XY child table 6 can be horizontally moved completely independently of the XY child table 1, and although the stroke of the XY child table 6 is large, the lead position recognition camera 17 can be moved easily and wasted time can be reduced. I can do it.

〔Effect of the invention〕

As described above, according to the present invention, during the wire bonding operation, the positions of the bonding points of all the leads to be bonded next are recognized and memorized, and the bonding operation and the lead position f recognition operation are performed. The wire bonding is performed in an over-ramp manner, which significantly improves the workability of wire bonding with a large number of pins, enables high-quality wire bonding, and facilitates high-speed automation.

[Brief explanation of drawings]

1 and 2 are explanatory diagrams showing embodiments of the present invention, respectively, FIG. 3 is a plan view showing an example of a bonding sample before IC assembly, Jl is a plan view showing a part of the lead frame, and FIG. 5 is a plan view after wire bonding in FIG. 3, and FIG. 6 is a sectional view taken along the line 1-1 in FIG. 5. l...Lead frame, 2...IC element, 3...
Pad, 4... Lead, 5... Wire, 6-1.6
-2... Detection mark, 10... Bonding sample, 11.16... XY child table 12... Bonding tool, 13... Bonding head, 14...
...Bonding Stage, 15...Prestige,
17... Lead position recognition camera, 19... Pad position recognition camera, 18... Recognition storage device, 20... Base frame, 21... ITV.

Claims (1)

[Claims] (1) In a wire bonding method in which a bonding sample with pads and leads to be bonded is sequentially conveyed to a bonding position at a constant pitch, a After the lead position recognition camera fixed to the XY table recognizes and stores the individual lead position coordinates of the bonding sample, the bonding sample is transported to the bonding position and the pad position recognition camera is fixed to the XY table at the position. 1. A wire bonding method characterized in that the position coordinates of a pad are recognized and stored, and this and the stored lead position coordinates are read back to perform bonding.