JPH0793328B2 - Die bonding method - Google Patents

Description

The present invention relates to a die bonding method, and more particularly to a bond position detecting method.

[Prior Art] Conventionally, as a die bonding method, for example, JP-A-57-
26448, JP 57-169250, JP 59-689
The one shown in Japanese Patent Publication No. 36 is known. This method detects a deviation amount of a work such as a lead frame or a substrate from a predetermined regular bond position, calculates an actual bond position of the regular bond position based on the deviation amount, and calculates a collet. Bonding is performed by moving to the actual bond position.

[Problems to be Solved by the Invention] By the way, in a lot, the amount of bond position deviation is generally constant, and the amount of deviation changes when the lot changes. However, in any of the above-described conventional techniques, the actual bond position of the work is detected every time the die is bonded, and the actual bond position of the work is calculated each time. That is, there is a problem that the bond position must be calculated every time the die is bonded.

An object of the present invention is to provide a die bonding method capable of reducing the calculation of the position coordinates of the actual work corners and the bond position coordinates.

[Means for Solving the Problems]

The above-mentioned problem is to use a die-bonding device in which a camera arranged offset from the collet by a certain distance moves on the plane together with the collet, and the position coordinates of two corners symmetrical with respect to the bond position of the regular work and the center thereof are used. The bond position coordinates of the above are stored in the arithmetic device in advance, the positions of the two corner portions which are symmetrical with respect to the actual bond position of the work are detected by the camera, and the position coordinates of these two points and the center position coordinates thereof are calculated by the arithmetic device. The die is bonded to the work by guiding the collet to the calculated center position coordinates, and the calculated position coordinates and center position coordinates of the corner portion of the actual work are normalized to the next actual work. The position coordinates and bond position coordinates of the parts are stored in the arithmetic unit, and in the next actual work, the corrected regular corner parts are stored. Moving the camera to position coordinates is solved by detecting.

[Action]

The camera detects the position coordinates of the two corners of the actual work, and if there is a displacement, the arithmetic unit calculates the position coordinates of these two points and their center position coordinates, and the actual position coordinates and center position The coordinates are stored in the arithmetic unit as the position coordinates and the bond position coordinates of the regular corner portion with respect to the next actual work. That is, the position coordinates and the bond position coordinates of the regular corner portion stored in advance in the arithmetic device are updated.

The amount of bond position deviation within a lot of work is almost constant, so for the next work in the same lot, move the camera to the position coordinates of the corner and bond position coordinates that have been updated once, and In most cases, there is almost no shift amount. In such a case, the bonding operation can be started without calculating the position coordinates of the corner portion and the bond position coordinates.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a bonding head 2 is fixed on an XY table 1 which is moved in the XY directions by a motor (not shown). The bonding head 2 is provided with a bonding arm 3 which can be moved up and down by a motor (not shown), and one end of the bonding arm 3 has a collet 4 at its lower end.
Is attached to the collet holder 5. A camera holder 7 holding a camera 6 is fixed to one end of the bonding head 2. Where camera 6
Is offset by a distance L with respect to the centerline of the collet 4. The work 8 is positioned and held on a work holding table 9.

Therefore, when the XY table 1 is driven, the collet 4
Both the camera 6 and the camera 6 can be moved in the XY directions.

FIG. 2 shows the work 8 positioned and held on the work holding table 9.
The two-dot chain line shows the case where the work 8 is properly positioned, and the solid line shows the actual position of the work 8.
Now, assuming that the coordinates of the two corners of the regular work 8 shown by the two-dot chain line are P ₁ (x ₁ , y ₁ ) and P ₂ (x ₂ , y ₂ ), the coordinates of the center, that is, the bond position P ( x, y) is x = (x ₁ + x ₂ ) / 2,
y = (y ₁ + y ₂ ) / 2. Therefore, each coordinate P ₁ (x ₁ , y
₁ ), P ₂ (x ₂ , y ₂ ) and P (x, y) are stored in advance in an arithmetic unit (not shown), the XY table 1 is driven during measurement by the instruction of the arithmetic unit and the camera 6 Is the coordinate P ₁ (x ₁ , y
₁ ) and P ₂ (x ₂ , y ₂ ), and the XY table 1 is driven at the time of bonding so that the collet 4 has a coordinate P.
It can be moved above (x, y).

Next, the operation will be described. XY table 1 is driven,
Collet 4 from the die pick-up position (not shown)
In the adsorption to pick up, first, the camera 6 is moved upward in one corner coordinates _{P 1 (x 1, y 1} ), the error Δx of the actual corner coordinate _{P 1 '(x 1',} y 1 ') , Δy ₁ is detected. Next, the camera 6 is moved above the other corner coordinate P ₂ (x ₂ , y ₂ ), and the actual corner coordinate P ₂ ′ (x ₂ ′,
The errors Δx ₂ and Δy _{2 of} y ₂ ′) are detected. After that, P ₁ ′
(X ₁ ′, y ₁ ′) and P ₂ ′ (x ₂ ′, y ₂ ′) are stored in the arithmetic unit as regular corner coordinates. Then, the error (Δ
The coordinates P ′ (x ′, y ′) of the actual bond position are calculated by x ₁ , Δy ₁ ) and (Δx ₂ , Δy ₂ ). That is, x ′ = x +
(Δx ₁ + Δx ₂ ) / 2, y ′ = y + (Δy ₁ + Δy ₂ ) / 2.
After that, the coordinates P '(x', y ') are stored in the arithmetic unit as a regular bond position. After the actual bond position is calculated as described above, the XY table 1 is then driven to move the collet 4 above the bond position coordinates P ′ (x ′, y ′). Then, the collet 4 is lowered and raised, and the work 8 is bonded with the die.

After the bonding is completed, the work 8 is sent by a moving means (not shown), and the next bond portion is sent to the bonding position. After that, the above operation is repeated. In this case, the corrected corner coordinates P ₁ ′ (x ₁ ′, y ₁ ′), P ₂ ′ (x ₂ ′,
y ₂ ′) and bond position coordinates P ′ (x ′, y ′) are processed as regular coordinates.

Although the camera 6 is attached to the bonding head 2 via the camera holder 7 in the above embodiment, it may be attached to the bonding arm 3.

[Advantages of the Invention] Using a die bonding device in which a camera arranged offset from the collet by a predetermined distance moves on a plane together with the collet, the position coordinates of two corners symmetrical with respect to the bond position of the regular work and the position coordinates thereof are used. The central bond position coordinate and the arithmetic unit are stored in advance, and the camera detects the positions of the two corner portions that are symmetrical with respect to the actual bond position of the work.
The position coordinates of these two points and the center position coordinates thereof are calculated by an arithmetic unit, and the die is bonded to the work by guiding the collet to the calculated center position coordinates, and the calculated position of the corner portion of the actual work. The coordinates and center position coordinates are stored in the arithmetic unit as the position coordinates and bond position coordinates of the regular corner portion for the next actual work, and in the next actual work, the corrected position coordinates of the regular corner portion are stored. Since the camera is moved and detected, the calculation of the actual position coordinates of the corners of the workpiece and the bond position coordinates can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of a die bonding apparatus used in the method of the present invention, and FIG. 2 is an explanatory view showing an example of a correction method of the present invention. 4: Collet, 6: Camera, 8: Work.

Claims (1)

[Claims] 1. A die-bonding device in which a camera arranged offset by a certain distance from a collet moves on a plane together with the collet, and position coordinates of two corner portions symmetrical to a normal work bond position and the coordinates thereof are used. The central bond position coordinates are stored in advance in the arithmetic device, the positions of two corner portions that are symmetrical with respect to the actual bond position of the work are detected by the camera, and the positional coordinates of these two points and their central position coordinates are calculated. And the die is bonded to the work by guiding the collet to the calculated center position coordinates, and the calculated position coordinates and center position coordinates of the corner portion of the actual work are normalized to the next actual work. The corrected position of the corner portion is stored in the arithmetic unit as the position coordinate of the corner portion and the bond position coordinate, and in the next actual work. Die bonding method characterized by detecting by moving the camera to position coordinates.