JPH11214428A - Bonding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bonding device where bonding work time can be shortened. SOLUTION: A strabismus lens 1c faces an object 11 and the lens 1c is supported so that an optical route passes through. The optical route passing through the lens 1c forms an image on the image pickup element of a camera head 1a. Adjusting is executed so that the focus Z of the optical route facing the object 11 matches the center Q of a bonding head 1. Even if the camera head 1a and the boding head 9 are separately arranged, a place where the camera 1 is recognized matches a place where the bonding head 9 is bonded and bonding is executed in the same position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bonding apparatus for bonding semiconductor components of a semiconductor integrated circuit (IC) or a large-scale integrated circuit (LSI), and more particularly to a pad on a chip as a semiconductor component to be bonded. The present invention relates to a bonding apparatus that performs recognition and bonding by using a camera as an imaging unit when bonding (electrode) and an external lead formed on a lead frame to which the chip is attached using a conductive wire.

[0002]

2. Description of the Related Art As shown in FIG. 5, a bonding apparatus for manufacturing a semiconductor integrated circuit (IC) or a large-scale integrated circuit (LSI) includes a camera 1 as an image pickup means including a camera head 1a, a lens 1b, and the like. A bonding head 9 having a tool (capillary) attached thereto and swingably supporting the tool, and XY capable of moving the camera 1 and the bonding head 9 mounted on an XY table in two-dimensional directions of X and Y directions. Object to be bonded consisting of table drive mechanism 2, lead frame 4 and chip 5
A bonding stage 3 for positioning 11 and an image processing device 6 for inputting and processing an image captured by the camera 1
A transport mechanism (not shown) for transporting and positioning the lead frame on the bonding stage 3; a table controller 8 for controlling the XY table drive mechanism 2; an image processing device 6 and a table controller 8 Control circuit that performs arithmetic control of
10 and a monitor 7 and the like.

[0003] The image processing device 6 includes a clock generation circuit, a horizontal and vertical synchronizing signal generation circuit, a clock pulse counting circuit, a multi-level conversion circuit, and the like.
Is composed of a microprocessor or the like.

In the above bonding apparatus, even when the camera 1 is located directly above the bonding head 9, the center of the lens 1b of the camera 1 and the center of the tool of the bonding head 9 are spaced apart by about 10 mm. ing. That is, in order to image a pad on a chip as a part to be bonded with the camera 1 and perform bonding with the tool of the bonding head 9, both the camera 1 and the bonding head 9 are mounted on an XY table. This is because it is necessary to avoid the tool of the bonding head 9 so that one optical axis can image the component to be bonded.

[0005] Therefore, in the bonding apparatus, the camera 1
The distance between the lens 1b and the tool of the bonding head 9 is set in advance when setting conditions such as self-teaching. This is called an offset amount.

As shown in FIG. 6, the offset amount is first detected by using a tool of a bonding head 9 on a pad as a first bonding point, a lead as a second bonding point, or another sample. Bonding.

[0007] The center P1 of the lens 1b of the camera ₁ is
Since the camera 1 is detected as coordinates on the XY table, the camera 1 is moved by the XY table driving mechanism 2 to the position above the sample, and the indentation 12 of the sample is detected.

[0008] The coordinate point of the detected indentation 12, that is, the tree
Distance between the center P ₁ of the lens before 1b to center P ₂ and the camera 1 in Le moves, i.e. is stored in the memory (RAM) as storage means in the control circuit 10 calculates the offset amount P.

As described above, since there is an offset amount P between the tool of the bonding head 1 and the lens 1b of the camera 1, the object 1 to be bonded, which is a part to be bonded, is imaged and recognized by the camera 1. The bonding is performed by moving the bonding head 1 onto the bonding target 11.

[0010] The above operation is performed between the pad as the first bonding point and the lead as the second bonding point, and a wire is connected between the pad and the lead. Then, this series of operations is repeatedly performed.

[0011]

Since the lens 1b of the camera 1 used in the bonding apparatus uses a direct-view lens as shown in FIG. 2, when performing a bonding operation, the bonding object 11 is imaged. After performing the recognition and positioning correction, the bonding is performed by moving the bonding head 1 by the offset amount P.

[0012] Since this operation is performed not only during the self-teaching but also when performing the actual bonding operation, there is a problem that it is difficult to shorten the bonding operation time. In particular, in the case of a semiconductor component having a large number of pins as in recent years, it is expected to achieve higher speed.

The present invention has been made in view of the above-mentioned drawbacks of the related art, and an object of the present invention is to provide a bonding apparatus capable of shortening a bonding operation time.

[0014]

According to the present invention, there is provided a bonding apparatus comprising: an XY table driving mechanism capable of moving an XY table in X and Y directions; and a tool mounted on the XY table and attached to a tip end thereof. Head, which is swingably supported, image pickup means provided above the bonding head, and an image pickup device for forming image information from a perspective lens, and a bonding object provided below the bonding head And a bonding stage for positioning and bonding, and a focus of an optical path between the oblique lens and the object to be bonded is made coincident with a bonding position of the bonding head.

[0015] Further, the oblique lens is constituted by a lens piece formed by using a part of a condensing lens.

[0016] Further, the oblique lens is provided with adjusting means for adjusting the angle of the optical axis.

Further, the oblique lens is formed of an optical element having a deflecting surface such as a diffraction grating.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A bonding apparatus according to the present invention will be described below with reference to the drawings. However, since the bonding apparatus according to the present invention has the same configuration as the conventional bonding apparatus except for the parts described below, the description of the same configuration and operation will be omitted and only the main part will be described. Further, in the following description and drawings, the same reference numerals are used for parts that are the same as or correspond to the above-described conventional configuration.

As shown in FIG. 1, the bonding apparatus includes a camera 1, an XY table driving mechanism 2, a bonding stage 3, an image processing apparatus 6, a monitor 7, a table control unit as in the conventional bonding apparatus. 8, a bonding head 9, a control circuit 10, and the like.

The camera 1 includes a camera head 1a and a perspective lens 1c in place of the conventional direct-view lens 1b. The oblique lens 1c is disposed above the bonding head 9.

As shown in FIG. 2, the conventional direct-view lens 1b is
An image of the object 11 is formed on the image sensor 13 over the entire surface of the lens 1b, that is, over the optical paths (a), (b) and (c). Accordingly, as can be seen from FIG. 2, the same image is formed in the images formed in the optical path of FIG. 2B also in FIGS.

Using this principle, the perspective lens 1c shown in FIG.
Is a lens piece formed by using only a part of the condensing lens L substantially the same as the direct-view lens 1b shown in FIG. 2, and captures an image of the object 11 only in one direction.
Therefore, although the light amount of the oblique lens 1c is smaller than that of the direct-view lens 1b, even if the obstacle 14 is interposed between the image sensor 13 and the object 11 as shown in FIG.
An image of the object 11 can be formed on the image 3.

FIG. 4 shows a second embodiment.

As shown in FIG. 4, the diffraction grating 1d is formed by an optical element having a deflecting surface. The diffraction grating 1 d forms an image of the object 11 on the image sensor 13 by folding the optical axis. This eliminates the need to dispose the direct-view lens 1b and the image sensor 13 on the vertical line of the object 11, and allows the image of the object 11 to be displayed on the image sensor 13 even if an obstacle exists in the space immediately above the object 11. An image can be formed.
The diffraction grating 1d operates in the same manner as the oblique lens 1c, and an optical element having a deflecting surface such as the diffraction grating 1d is also included in the oblique lens in a broad sense.

Next, an embodiment applied to a bonding apparatus using the oblique lens 1c shown in FIG. 3 will be described.
Note that the same can be applied to the case where an optical element such as the diffraction grating 1d shown in FIG. 4 is used.

As shown in FIG. 1, a camera head 1a having a perspective lens 1c is located directly above a bonding head 9 (FIG. 1).
In the figure, the position is shifted from the bonding head 9. ), And the oblique lens 1c is positioned and supported so that the lens barrel and lens of the lens 1c face the stage 3a of the bonding stage 3. That is, as shown in FIG. 3, a lens 1c is attached to an object 11 composed of a lead frame 4 and a chip 5.
And the lens 1c is positioned and supported so that the optical path (a) passes therethrough, so that the optical path (a) passing through the lens 1c forms an image on the image sensor of the camera head 1a. At this time, the optical path (a) directed to the object 11
Is adjusted so that the focal point Z (shown in FIG. 1) and the center Q of the bonding head 1 substantially match. That is, camera 1
The bonding head 9 and the bonding head 9 are both mounted on an XY table.
Because performs a swinging movement in the vertical direction shown in the optical axis of oblique lens 1c (central axis) P ₃ passes through the bonding object 11 on the stage 3a, and at this time, tool of the bonding head 9 - The object Q is also the bonding object 1
Set to pass 1

In FIG. 1, the setting is made with the bonding object 11, but the setting may be made at any other suitable place. In addition, since the field of view of the camera 1 can capture, for example, a plurality of pads and leads in the same field of view, the center of the tool may be set in the field of view. Since the focus Z is adjusted by the camera 1, if the optical path (a) and the tool center of the bonding head 9 are made to substantially coincide with each other, the focus Z can be adjusted automatically or manually. Can be.

The adjustment of the optical axis is performed by moving the fiber if the lens barrel of the lens 1c is an optical fiber or the like. The angle of the shaft may be adjusted.

By doing so, the camera head 1a
Even when the bonding head 9 and the bonding head 9 are spaced apart, bonding can be performed at the same position because the recognition of the camera 1 and the bonding position of the bonding head 9 with the tool are substantially the same.

Next, the bonding operation performed by the bonding apparatus will be described.

First, the detection of the offset amount between the bonding head 9 and the camera 1, which is one of the conditions for the self-teaching before the bonding step, is described with reference to the perspective lens 1c.
Optical axis P ₃ and the center Q of the tool of the bonding head 9
It is unnecessary if the adjustment is made. Therefore, the position of the tool of the bonding head 9 during the bonding operation (stage 3)
a) on a straight line perpendicular to the XY plane) is directly imaged by the camera 1, and after positioning the leads or pads, bonding is performed by the tool of the bonding head 9 without moving the camera 1. Just do it.

In the bonding operation according to the present invention, the camera 1 can recognize the position of the bonding head 9 between the pad as the first bonding point and the lead as the second bonding point at the same time as the movement of the bonding head 9 can be performed.
This eliminates the need for a moving step corresponding to the offset amount, and can reduce the bonding work.

In the bonding apparatus according to the present invention,
It is not necessary to detect the offset amount between the bonding head 9 and the camera 1 and to move and position the offset amount at the time of bonding. However, the adjustment of the offset amount can be performed with high accuracy by performing the adjustment together with the conventional method. .

Further, the oblique lens according to the present invention is not limited to the above-described configuration, and various optical devices,
An optical element configured by combining optical elements and other means can also be applied.

The bonding apparatus according to the present invention can be applied not only to a wire bonding apparatus but also to a tape bonding apparatus and other bonding apparatuses.

[0036]

As described above, in the bonding apparatus according to the present invention, the position at which bonding is performed by the tool of the bonding head is simultaneously imaged by the oblique lens provided in the camera. Therefore, there is no need to perform the step of detecting the offset amount between the bonding head and the camera and the movement and positioning of the camera by the offset amount, so that the work process can be shortened, and the overall bonding work time can be shortened. it can.

[Brief description of the drawings]

FIG. 1 is a configuration diagram schematically showing a bonding apparatus of the present invention.

FIG. 2 is a diagram illustrating the principle of a direct-view lens.

FIG. 3 is a diagram illustrating the principle of a perspective lens according to the present invention.

FIG. 4 is a diagram illustrating a perspective lens according to a second embodiment of the present invention.

FIG. 5 is a configuration diagram schematically showing a conventional bonding apparatus.

FIG. 6 is a diagram illustrating detection of a conventional offset amount.

[Explanation of symbols]

 Reference Signs List 1 camera 1a camera head 1c perspective lens 2 XY table drive mechanism 3 bonding stage 3a stage 7 monitor 9 bonding head 11 bonding target

Claims (4)

[Claims] An XY table driving mechanism capable of moving an XY table in X and Y directions, a bonding head mounted on the XY table and swingably supporting a tool attached to a tip end thereof; Imaging means having an imaging element disposed above the bonding head and imaging image information from a perspective lens; and a bonding stage disposed below the bonding head for positioning a bonding object and performing bonding. A bonding apparatus, wherein a focus of an optical path between the oblique lens and the object to be bonded is substantially coincident with a bonding position of the bonding head. 2. The bonding apparatus according to claim 1, wherein the oblique lens is configured by a lens piece formed by using a part of a condenser lens. 3. The bonding apparatus according to claim 1, wherein the oblique lens includes an adjustment unit that can adjust an angle of an optical axis. 4. The bonding apparatus according to claim 1, wherein the oblique lens is formed of an optical element having a deflection surface such as a diffraction grating.