JP2568125B2 - Bonding device tool / camera offset amount detection mechanism and method - Google Patents

Description

The present invention relates to a semiconductor integrated circuit (IC) and a large-scale integrated circuit (LS).
More specifically, the present invention relates to a bonding apparatus for bonding semiconductor components, and more particularly to a mechanism for detecting an offset amount between a tool of a tape bonding apparatus and a camera and a method therefor when performing tape bonding.

[Background Art] A tape bonding apparatus for manufacturing a semiconductor integrated circuit (IC) or a large-scale integrated circuit (LSI) is bonded to a camera 1 including a camera head 1a, a lens 1b, etc. as shown in FIG. The head 9 and the camera 1 and the bonding head 9 can be moved in the X and Y directions.
An XY table drive mechanism 2, an XYθ table drive mechanism 3 that is rotatable in X, Y and θ directions for positioning the tape 4 and the chip 5 imaged by the camera 1, and an image to which the output of the camera 1 is input. A processor 6, a table controller 8 for controlling the XY table drive mechanism 2 and the XYθ table drive mechanism 3, a control circuit 14 for storing and controlling information from the image processor 6 and the table controller 8, a monitor 7, etc. It is composed of.

The image processing device 6 includes a clock generation circuit, a horizontal and vertical synchronization signal generation circuit, a clock pulse counting circuit and 2
Particularly, in the binarization circuit, for example, in the binarization circuit, for example, the portion of the lead post is lightened and the portion to be read is set to "1", and the other portion is darkened to "0".
As described above, the control circuit is configured to be digitized and readable, and stores and controls such information.
Reference numeral 14 is composed of a microprocessor and the like.

By the way, the camera 1 and the bonding head 9 are
Since it is mounted on the XY table drive mechanism 2, each position can be detected as a coordinate position on the XY table drive mechanism 2.

In the tape bonding, it is generally necessary to relatively match the leads on the tape 4 side formed in a film shape with the bumps on the chip 5 positioned on the positioning base, and the leads formed on the tape 4 side. The chip 5 as the component to be bonded is rotated in the θ direction and displaced in the X and Y directions so that the bumps on the chip 5 to be bonded are relatively aligned with each other.
In order to perform such tape bonding accurately, it is necessary to detect the distance between the center of the lens 1b of the camera 1 and the center of the tool of the bonding head 9, that is, the offset amount and store it in the memory circuit in the control circuit 14. There is.

As a method of detecting this offset amount, temporary bonding is performed on the sample using a tool of the bonding head 9 as shown in FIG. The indentation formed on this sample is detected by the camera 1. Since the center position of the lens 1b of the camera 1 in FIG. 6 is detected as a coordinate on the XY table drive mechanism 2, the camera 1 is moved by the XY table drive mechanism 2 to the position above the sample. This camera 1
The indentations at the four corners of the sample formed by the tool of the bonding head 9 are detected, and the coordinate position of the center of the sample is obtained from the coordinate points of the detected indentations to be the center coordinates of the tool. The distance between the obtained coordinate position and the center position of the lens 1b of the camera 1 is calculated as an offset amount (CTD).

[Problems to be Solved by the Invention] However, in the conventional method of detecting the offset amount in the tape bonding apparatus, firstly, the binary mark circuit in which the indentation of the temporarily bonded sample is built in the image processing apparatus 6 is firstly provided. However, there is a drawback in that the image picked up by this binarization circuit is very difficult to see and difficult to detect. Therefore, it takes a long time to measure the offset amount, and the same work is required when the bonding tool is replaced, so that there is a drawback that work efficiency is reduced. Secondly, the bonding tool must be replaced according to the shape of the component to be bonded, but in the case of a tool having a size substantially equal to the size of the bump as shown in FIG. 7, indentations are likely to remain on the sample. However, when a tool larger than the size of the bump is used, there is a drawback that the indentation is hard to remain due to the influence of the elastic force of the lead. Therefore, there is a drawback that the offset amount cannot be accurately calculated by such a method.

Therefore, the present invention has been made in view of the above-mentioned drawbacks of the prior art. Even when the tool of the bonding head is exchanged, it is possible to accurately calculate and measure the offset amount without performing provisional bonding on the sample. An object of the present invention is to provide an offset amount detecting mechanism for a tool of a bonding apparatus and a camera, and a method thereof.

[Means for Solving the Problems] The present invention is directed to a camera, a bonding head for bonding, an XY table drive mechanism capable of moving the camera and the bonding head in the X and Y directions, and facing the camera and the bonding head. The edge of the tool of the bonding head is detected on the side of the edge of the bonding head, and the image processing control means capable of inputting the outputs of the camera and the edge detecting means and performing a storage operation based on the input information. The tool center is calculated from the edge coordinates of the tool of the bonding head obtained by the edge detection means, and the image processing control means detects the offset amount between the tool and the camera.

Further, the present invention obtains the coordinate position of the edge detecting means capable of detecting the edge of the tool of the bonding head provided on the side facing the camera by the camera mounted on the XY table driving mechanism, and detecting the edge. The tool of the bonding head is moved in the vicinity of the edge detection position of the means, the tool of the bonding head is moved from the position in the X direction and the Y direction to detect the edge coordinates of the tool, and the image processing control means based on the coordinates. The center position coordinates of the tool are calculated, and the offset amount between the tool and the camera is detected based on the obtained coordinates.

Further, according to the present invention, the coordinate position of the edge detecting means capable of detecting the edge of the tool of the bonding head provided on the side opposite to the camera mounted on the XY table drive mechanism is obtained in advance in the storage means. Based on the obtained coordinate position information, the camera moves above the edge detecting means to obtain the coordinate position of the edge detecting means again, and the position information obtained in advance is corrected and stored. It was done like this.

[Embodiment] Next, an embodiment of the present invention will be described in detail with reference to the drawings. It should be noted that components having the same configurations and functions as those of the device shown in FIG.

A tape bonding apparatus according to the present invention is a camera 1 including a camera head 1a, a lens 1b, etc. as shown in FIG.
A bonding head 9 for bonding, an XY table drive mechanism 2 capable of moving the camera 1 and the bonding head 9 in the X and Y directions, and X for positioning the tape 4 and the chip 5 imaged by the camera 1. Y
XYθ table drive mechanism 3 that can rotate in both directions and θ directions
And the image processing device 6 to which the output of the camera 1 is input.
And XY table drive mechanism 2 and XYθ table drive mechanism 3
And a table control unit 8 for controlling the image processing apparatus and a control circuit for storing and controlling information from the image processing apparatus 6 and the table control unit 8.
14 and a monitor 7 and the like.

In the tape bonding device having the above configuration,
As shown in FIG. 2, the tool edge detector 10 of the bonding head 9 is provided on the device housing 12. The tool edge detector 10 is a reflection type optical fiber detector, and is composed of a portion that projects light from the tip of the fiber and a portion that receives light reflected by an object to be detected. The light projected from this fiber impinges on the tool edge portion of the bonding head 9 and receives the reflected light, which is photoelectrically converted within the tool edge detector 10 and input into the control circuit 14. .

A method of detecting the offset amount using this tool edge detector 10 will be described below.

First, the condition setting necessary for detecting the offset amount (hereinafter referred to as self-teaching) is performed.

As shown in FIG. 1, the center coordinate position of the lens 1b of the camera 1 is the origin (0,0). Since this origin coordinate is input as a coordinate position on the XY table drive mechanism 2, the camera 1
X _{D in} the X direction and Y _{D in} the Y direction by the XY table drive mechanism 2.
The tool edge detector 10 is moved and imaged, and the position of the tool edge detector 10 is binarized by the image processing device 6 and stored in the memory circuit of the control circuit 14. This coordinate is (x _D , y _D )
And Next, the tool of the bonding head 9 is moved above the tool edge detector 10 by the XY table drive mechanism 2 by a manipulator (not shown). Next, the tip of the tool of the bonding head 9 is lowered in the Z direction so as to be positioned so that the tool edge detector 10 is in the light irradiation range. This moving and descending amount Z _T (shown in FIG. 2) is also input and stored. The input of this moving and descending amount Z _T is the tool edge detector 10
Is mounted on the device housing 12, it is necessary to consider the capability of the detector when detecting the return light of the light emitted from the fiber. At this stage, move the tool outside the tool edge, that is, in the direction A → B in FIG.
In the B → A direction, the C → D direction, and the D → C direction (it should be noted that the coordinate points A, B, C, and D are not obtained at this point, so they are located near the tool edge detector 10). After scanning, the tool edge detector 10 detects an edge, and a temporary coordinate position is input and stored. Based on the data of the coordinate position, the control circuit 14 calculates the center (x _T ′, y _T ′) of the tool of the bonding head 9 and stores it. next,
Coordinate point of the center of the tool _{(x T ', y T'} ) are obtained,
Moreover, since the size of the tool is input in advance by an external operation key, a search area for automatic detection of the offset amount on the coordinate axes in the X and Y directions passing through the center of the tool.
The coordinates A, B, C, D of 11 are input by an external key operation (not shown). Even if the tool size changes, the search area 11 is again input according to the tool size by an external operation key. This input is the tool center coordinate point (x _T ′, y
_{Since T} ') is known, it can be easily input. When the above conditions are set, the self-teaching is completed.

Next, an automatic offset amount detecting method according to the present invention will be described below with reference to the flowchart of FIG.

As shown in FIG. 3, when the automatic detection of the offset amount between the center of the tool and the center of the lens 1b of the camera 1 in the tape bonding apparatus is started, the coordinate point (0,
The camera 1 located at (0) moves to a coordinate (x _D , y _D ) where the tool edge detector 10 is located, recognizes the position of the tool edge detector 10 and inputs the coordinate (x _D , y _D ) again ( Step
S ₁ ). This is because the re-input of the coordinates in step S ₁ may cause an error due to thermal deformation of the device, etc., although the tool edge detector 10 is fixed. Then step S ₂
In the self-teaching, since the coordinate points A, B, C, D of the search area 11 are stored, the coordinate point A moves directly above the tool edge detector 10 and drops to the detection height.
In step S _3, it is moved in the X direction (A → B direction). This movement amount is set larger than the distance between the point A and the edge because the coordinate position of the point A and the size of the tool are input. This is a tool edge detector 10 as shown in FIG.
It is set in consideration of the fact that hysteresis occurs when the level is detected. In the present embodiment, the hysteresis appearing on the output side is scanned in both directions A and B (C and D), so that the tool center can be accurately measured. Next, in step S ₄ , it is determined whether or not the tool edge detector 10 is in the operating state. If the tool edge detector 10 is off (OFF), step S ₃ is repeated, and if it is on (ON), the coordinate A ′ is obtained. (X ₁ , y _T ) is detected and stored, and then the process moves to step S ₅ , where the coordinate point B of the search area 11 is moved right above the tool edge detector 10 and lowered to the detection height. These movements are controlled by the control circuit 14. Next, in step S ₆ moves in the -X direction (B →
A direction). This movement amount is set in the same manner as in step S ₃ . The edge of the tool is detected by this movement, but the tool edge detector 10 is off (OFF).
In the case of, the step S ₆ is performed again, and in the case of ON, the coordinate B ′ (x ₂ , y _T ) is detected and stored, and the process proceeds to the next step S ₈ . In step S ₈ the control circuit 14 which is the center coordinates of the tool performs an operation to calculate the (x _T). This calculation is performed as follows.

That is, coordinates A 'is _{(-x 1 + x D, -y} T' is obtained as + y _D) coordinates B 'are _{(-x 2 + x D, -y} T' + y D).

Here, y _T ′ is a temporary coordinate point obtained during self-teaching.

From the above coordinates, Is.

As a result, the center coordinate point x _T of the tool on the X axis and the distance X _{T from} the center of the lens 1b of the camera 1 are obtained.

Next, in step S ₉ , the coordinate point C moves to a position right above the tool edge detector 10 and drops to the detection height. Step S
Move in the Y direction at ₁₀ (C → D direction). Step S ₁₁
Whether tool edge detector 10 is in the operating state is determined in off step S ₁₀ in the case of (OFF)
Is repeated, and when it is on (ON), the coordinates C '(x _T ,
y ₁ ) is detected and stored, and the process proceeds to step S ₁₂ , where the coordinate point D of the search area 11 moves directly above the tool edge detector 10 and is lowered to the detection height. Moving in step S ₁₃ in the -Y direction is (D → C direction), when the tool edge detector 10 is off (OFF) Repeat Step S ₁₃ in step S _14,
Coordinates _{D '(x T, y 2} ) If on (ON) is detected and stored, it calculates the y _T is the center coordinates of the tool performs an operation in step S _15. This calculation is performed as follows.

That is, the coordinates C 'is (-x _T' is obtained as _{+ x D, -y 1 + y} D) coordinates D 'is _{(-x T' + x D,} -y 2 + y D).

Here, x _T ′ is a temporary coordinate point obtained at the time of self-teaching.

From the above coordinates, Is.

As a result, the coordinate point y _T of the tool center on the Y axis and the distance Y _{T from} the center of the lens 1b of the camera 1 are obtained.

From the above, the coordinate point (x _T , y _T ) of the tool center and the camera 1
The distances X _T and Y _{T from the} center coordinate point (0,0) of the lens 1b are obtained.

As described above, the offset amount can be automatically calculated, but according to the present embodiment, the control circuit uses the position coordinates of the tool, the tool edge detector 10 and the camera 1 as data.
Since it is stored in the storage circuit of 14, it is possible to reliably detect the offset amount even if there is an error in the positional accuracy of the tool edge detector 10.

Although the offset amounts X _T and Y _T are obtained in separate steps in the present embodiment, since they are stored as data in the control circuit 14, X _T and Y _T may be obtained at the same time. Also, the image processing device 6 and the table control unit 8
Also, the control circuit 14 may be integrally configured. Further, although the optical fiber detector is used as the means for detecting the tool edge in this embodiment, it may be detected by contacting the tool edge surface with a dial gauge or the like. Further, although the present invention detects the tool edge from the outside of the tool toward the inside, the tool edge may be detected by scanning in the opposite direction.

Further, the present invention is not limited to the tape bonding device and can be applied to other devices.

As described above, according to the present invention, since the tool edge detector automatically calculates and calculates the center of the tool of the bonding head, the offset amount can be accurately obtained. Moreover, since the time required for measurement can be reduced, there is an effect that work efficiency is improved. Also,
According to the present invention, the time required for the offset amount can be shortened even when the bonding tool is replaced. Further, according to the present invention, since the position of the tool edge detector is recognized again by the camera,
Even if an error occurs in the position of the tool edge detector due to thermal deformation or the like, an accurate value can be input and stored, so that a highly accurate result can be obtained.

[Brief description of drawings]

FIG. 1 is an embodiment of the present invention and is an explanatory view for explaining a method of detecting an offset amount between a tool and a camera of a bonding apparatus according to the present invention, and FIG. 2 is a tool, a camera and a tool edge of FIG. Diagram illustrating the positional relationship of detectors,
FIG. 3 is a flow chart showing a method of detecting the offset amount of the present invention, FIG. 4 is an explanatory view explaining an output error when a tool edge detector is used, and FIG. 5 is a schematic configuration of a conventional tape bonding apparatus. FIG. 6 is an explanatory diagram for detecting the conventional offset amount, and FIG. 7 is a diagram for explaining a method for detecting an indentation of a tool by using the method according to FIG. 1 ... Camera, 1a ... Camera head, 1b ... Lens, 2
...... XY table drive mechanism, 3 ... XYθ table drive mechanism, 4 ... tape, 5 ... chip, 6 ... image processing device, 7 ... monitor, 8 ... table control unit, 9 ... bonding head, 10 …… Tool edge detector, 11 …… Search area, 12 …… Device housing.

Claims (4)

(57) [Claims] 1. A camera, a bonding head for bonding, an XY table drive mechanism capable of moving the camera and the bonding head in the X and Y directions, and a bonding head tool on the side facing the camera and the bonding head. It is provided with an edge detecting means capable of detecting an edge and an image processing control means to which outputs of the camera and the edge detecting means are inputted and which can perform a storage operation based on the inputted information. The offset amount between the tool and the camera of the bonding apparatus characterized in that the center of the tool is calculated from the edge coordinates of the tool of the bonding head and the offset amount between the tool and the camera is detected by the image processing control means. Detection mechanism. 2. An offset amount detecting mechanism between a tool of a bonding apparatus and a camera according to claim 1, wherein the edge detection by said edge detecting means is an optical detection. 3. A coordinate position of edge detecting means capable of detecting an edge of a tool of a bonding head provided on a side facing the camera by a camera mounted on an XY table driving mechanism, and the edge detecting means is obtained. Of the bonding head is moved to the vicinity of the edge detection position, the tool of the bonding head is moved in the X direction and the Y direction from the position to detect the edge coordinate of the tool, and the image processing control means uses the tool to detect the edge coordinate. Calculate the center position coordinates of
A method for detecting the offset amount between the tool and the camera of the bonding apparatus, wherein the offset amount between the tool and the camera is detected based on the obtained coordinates. 4. A coordinate position of an edge detection means capable of detecting an edge of a tool of a bonding head provided on a side facing the camera by a camera mounted on an XY table drive mechanism is previously obtained and stored in a storage means. Based on the obtained coordinate position information, the camera moves above the edge detecting means to obtain the coordinate position of the edge detecting means again, and the position information obtained in advance is corrected and stored. A method of detecting an offset amount between a tool of a bonding apparatus and a camera, which is characterized by the above.