JPH01183127A - Die bonding method - Google Patents

Abstract

PURPOSE:To enhance productivity and perform highly accurate bonding even if bonding positions scatter by a method wherein two corners are detected by a camera and a positional error is automatically corrected so as to bond at the center. CONSTITUTION:A device whereby a camera 6 offset from a collet 4 with a certain distance moves together with the collet 4 on a plane is used. Two corners symmetrical with respect to a work bonding position where a die is to be bonded are detected by the camera 6, and the center of these two points is calculated by an arithmetic device. After the bonding position is calculated, an XY table 1 is driven, and the collet 4 is moved to an upper portion of the coordinate of the bonding position and then lowered or raised, to have the die bonded on a work 8. This realizes a die bonding method by which the bonding position can be rapidly and accurately detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a die bonding method, and more particularly to a bond position detection method.

[Prior Art] In a conventional die bonding method, a collet is visually moved to a bond position on a lead frame or a package (hereinafter referred to as a work), and data of an arithmetic device is corrected based on the actual detected position.

[Problems to be Solved by the Invention] The above conventional technology requires a large amount of detection time because it is a visual inspection, and also has the problem that if the bond position of the workpiece varies, the variation directly affects the bonding accuracy. was there.

An object of the present invention is to provide a die bonding method that can detect bond positions quickly and with high precision.

[Means for Solving the Problems] The above problem is solved by using a die bonding device in which a camera arranged offset from a collet by a certain distance moves on a plane together with the collet, and from the bonding position of the workpiece to which the die is bonded. The problem is solved by detecting the positions of the two symmetrical corners using the camera, calculating the center of these two detected positions using a calculation device, guiding the collet to the calculated center position, and bonding the die to the workpiece. be done.

[Operation] When two corners symmetrical to the bond position are detected by the camera, the center, that is, the bond position, is automatically calculated, and the die is bonded to the center position by the collet.

[Example] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, a bonding head 2 is fixed on an XY child table that is moved in the XY force directions by a motor (not shown). The bonding head 2 is provided with a bonding arm 3 that is moved up and down by a motor (not shown), and a collet holder 5 holding a collet 4 at its lower end is attached to one end of the bonding arm 3.

Further, a camera holder 7 holding a camera 6 is fixed to one end of the bonding head 2.

Here, the center line of the camera 6 is offset from the center line of the collet 4 by a distance. Further, the workpiece 8 is positioned and held on a workpiece holding table 9.

Therefore, when the XY child table is driven, the collet 4 and camera 6 are both moved in the XY force direction.

Figure 2 shows a workpiece 8 positioned and held on a workpiece holding table 9.
The two-dot chain line shows the case where the workpiece 8 is properly positioned, and the solid line shows the actual position of the workpiece 8. Now, if the coordinates of the two corners of the regular work 8 shown by the two-dot chain line are P+ (X+, y+) and P2 (X2 +'V2), then the coordinates of the center, that is, the bond position P (x,
y) is y, = (xl + X 2 ) / 2,
y=(y I +72)/2. Therefore, each of the coordinates P+ (X+, VI), P2 (X2, Y
2), P(x, y) is stored in advance in an arithmetic device (not shown), and the XY child table is driven at the time of measurement according to a command from the arithmetic device, and the camera 6 obtains the coordinate P1 (xl, y).
, ) and P2 (x21Y2), and at the time of bonding, the XY child table is driven so that the collet 4 is moved above the coordinates P (x, y).

Next, the effect will be explained. When the XY child table is driven and the collet 4 adsorbs and picks up a die from a die pickup position (not shown), the camera 6 is first moved above one corner coordinate P, (x++Y,), and the actual corner coordinate P+ '(X+', VI
') error ΔX I +Δy1 is detected. Next, the camera 6 is moved above the other corner coordinate P2 (X2, Y2), and the actual corner coordinate P2' (X2
'+72') error ΔX2t Δy2 is detected. From now on, Pl''(X1'・y+'), P2'(x2'
+y2') is stored in the arithmetic unit as a regular corner coordinate. Then, the error (ΔX1.Δy+), (ΔX
2+Δy2), the actual bond position coordinate P'(x
', y') are calculated. That is, x'=X+(ΔX1+
ΔX2)/2', y' = y+ (Δy1+Δy 2
' ) / 2. Hereafter, the coordinates P'(x', y')
is stored in the arithmetic unit as a regular bond position. After calculating the actual bond position as described above, the XY child table is then driven and the collet 4 calculates the bond position coordinate P'(x
', y''). Thereafter, the collet 4 is lowered and raised, and the die is bonded to the workpiece 8.

After the bonding is completed, the workpiece 8 is sent by a moving means (not shown), and the next bonding part is sent to the bonding position. Thereafter, the above operation is repeated. In this case, the corrected corner coordinates P+'(X1'・yl"), P2' (
x2', y2'), bond position coordinates P'(x' +
y') are treated as normal coordinates.

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

[Effects of the Invention] According to the present invention, two corners are detected with a camera, positional errors are automatically corrected, and bonding is performed at the center.
It is highly productive and can perform bonding with high precision even if the bond position varies.

[Brief explanation of the drawing]

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

Claims (1)

[Claims] (1) Using a die bonding device in which a camera arranged at a certain distance offset from the collet moves on a plane together with the collet, the positions of two corners symmetrical from the bonding position of the workpiece to which the die is bonded are determined as follows. A die bonding method characterized by detecting with a camera, calculating the center of these two detected positions with an arithmetic device, and guiding a collet to the calculated center position to bond the die to the workpiece.