JPH02248054A - Calculation of angle of bonding component - Google Patents

Abstract

PURPOSE:To determine the angle of inclination of a bonding component by a method wherein the lengths between a plurality of points along the sides of the bonding component and the reference coordinate point are calculated and the found length to each coordinate point is added. CONSTITUTION:In reference coordinates (R1 to R4) selected from among arbitrary coordinates on each side of a pellet 2 positioned on an X-Y table, coordinate axes x1, x2, y1 and y2 are formed of each line parallel to coordinate axes to pass the origin of the X-Y table in directions X and Y. A plurality of arbitrary points on each side, which is extended from the reference coordinates R1 to R4 to the directions X and Y, are selected and the coordinate points of these points are found. A plurality of similar coordinate points are found on each side. Data on these found coordinate points is stored. The lengths between the reference coordinate points and each selected coordinate point in the directions X and Y are found as data on axes X and Y on the basis of the stored data and the found length to each coordinate point is added in the directions X and Y and the accurate angle of inclination of the pellet can be calculated from each line to pass between the coordinate points.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to semiconductor integrated circuits (IC) and large-scale integrated circuits (L
SI)'s bonding equipment for semiconductor components, especially when mounting a pellet with a die bonder or tape bonder, the bonding system is capable of calculating accurate angles using the angle data of the pellet detected by the recognition device in the image processing device. The present invention relates to a method for calculating angles of parts.

[Background technology] Semiconductor integrated circuits (IC) and large-scale integrated circuits (LSI)
), it is necessary to transport pellets arranged on a wafer ring or tray and place them on a positioning table or lead frame.

At this time, the center position and rotation angle of the pellet are calculated by the image processing device.

FIG. 3 shows a conventional example of detecting the inclination angle of a belet. In FIG. 3, an arbitrary side of the pellet l is selected, and the inclination of the pellet l is calculated from the coordinates of two arbitrary points on this side, AI and A2. This tilt angle θ is determined by the coordinates of AI and A2 being XY.
Since it can be read from the coordinates on the table (regular coordinates have been input into the storage circuit of the image processing device in advance), let the length in the X direction between AI and A2 be X.

Let Y be the length in the Y direction.

θ = Tan − Otori (Y/x) ・ ・ ・
The angle θ can be determined by (1).

[Object to be Solved by the Invention] However, in the conventional method for detecting the inclination angle of a belet, the data processed by the recognition circuit in the image processing device is a digital signal, as shown in FIG. The waveform becomes step-like. Therefore, if two arbitrary fixed point selection points 1, for example A4 or A5, are selected as data for detecting the inclination angle θ, the data will be θ1 or θ2, resulting in an angular error. This angular error has the disadvantage that the resolution of the detected angle is reduced in an apparatus in which the value of one pixel has a large meaning due to the chipping of the sides during bullet formation and the processing capacity of the recognition circuit. Such an angular error becomes a non-negligible range when the number of lead bins and the pitch of bats or bumps becomes smaller, and there is a possibility that bonding cannot be performed in fully automatic bonding.

Therefore, the present invention was made in view of the above-mentioned drawbacks of the prior art, and it selects an arbitrary side of the pellet, selects a plurality of arbitrary coordinate points of this side in the X direction and Y direction, and selects a plurality of arbitrary coordinate points from the reference coordinate points. Find the length to each coordinate point on the XY axes, add the lengths of each coordinate point, and calculate the
It is an object of the present invention to provide a method for calculating the angle of a bonding component, which can detect the inclination angle by determining each coordinate point in the direction.

[Means for Solving the Problems] The present invention selects an arbitrary side of a bonding component placed on a positioning table, sets an arbitrary point on the xy seat of the selected side as a reference coordinate point, and Select a plurality of arbitrary points along the side from a fixed point on the reference coordinates, find the xY coordinates of the selected points, store the obtained coordinate data, and use the data to select a plurality of points from the fixed point. The inclination angle of the bonding part is detected by calculating the length on the XY axes of each selected coordinate point and adding the lengths of the calculated coordinate points on the XY axes. It is.

[Example] Next, the present invention will be explained in detail using the drawings.

FIG. 1 is a diagram illustrating the present invention in detail.

3 in FIG. 1, 2 is a pellet positioned on a positioning stand on an XY table. R1.

R2, R3, and R4 are reference coordinates that select arbitrary coordinates on each side of the pellet 2 and serve as measurement standards.

These reference coordinates (R1, R2, R3, R4) are.

Coordinate axes xi, x2, yl in the X and Y directions with lines parallel to the coordinate axes passing through the origin of the xY table.

form y2. A plurality of arbitrary points on each side extending in the X direction and Y direction from the reference coordinates R1 to R4 are selected, and these coordinate points are determined. Bundle multiple similar coordinate points on each side. The data of this determined coordinate point is stored in a storage circuit within the image processing device. Based on this stored data, as shown in Figure 2, the length from the reference coordinate point to each selected coordinate point in the X and Y directions is determined as data on the XY axes, and each of the determined coordinates is The length of the point in the X direction and Y direction
The inclination angle is detected from the line passing between each coordinate point by adding in the direction.

This calculation method will be specifically explained below.

A plurality of coordinate points are detected from a plurality of sides of the pellet 2 shown in FIG. 1, and ai and bi are determined from the detected coordinate points.

For example, coordinate point Pl = (at, bl), P2 = (
a1+a2. bl+b2)... is obtained.

The data obtained by equation (2) are averaged by the least squares method as shown in FIG. 2 to obtain the slope.

Obtained slope = Σb/Σa ...(3) Therefore, coordinate points (aα, bα) that do not exist within the data corresponding to the Iα pixel based on the slope straight line of equation (3) are treated as abnormal data. Make sure to exclude it.

If the slope obtained from equation (3) is B/A, then θ = Ta n (B/A) ・　・　・(4) Thus, the tilt angle θ can be calculated.

This tilt angle is calculated within the image processing device.

[Effects of the Invention] As explained above, according to the present invention, an arbitrary side of the bellet is selected, a plurality of arbitrary coordinate points of this side in the X direction and Y direction are selected, and Find the length to each coordinate point, add the lengths of each coordinate point to find each coordinate point in the X direction and Y direction, and detect the tilt angle by averaging the obtained data. This makes it possible to obtain data with higher reliability than the pixel resolution of the image processing device. Further, according to the present invention, by excluding abnormal data from the obtained data, there is an effect of preventing the probability of calculating the slope from incorrect data due to chipping of the edges of the pellet, etc. This allows highly accurate positioning of bonding parts.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are one embodiment of the present invention, and FIGS. 3 and 4 are detailed explanatory diagrams of the present invention, and FIGS. 3 and 4 are explanatory diagrams illustrating a conventional method for calculating the angle of bonding parts. Figure 1 1...Bellet, 2...Bellet.

Claims (3)

[Claims] (1) Select any side of the bonding part placed on the positioning table, set any point on the XY coordinates of this selected side as the reference coordinate point, and move along the side from the fixed point on this reference coordinate. Select a plurality of arbitrary points, find the XY coordinates of the selected points, store the obtained coordinate data, and use the data to calculate the distance on the XY axis from the fixed point to each of the plurality of selected coordinates. Calculate the length of X
A method for calculating an angle of a bonding component, characterized in that the inclination angle of the bonding component is detected by adding the lengths of respective coordinate points on the Y-axis. (2) The method for calculating the angle of a bonding component according to claim 1, characterized in that an average value of the determined coordinate data is calculated and stored. (3) The angle of the bonding component according to claims 1 and 2, wherein data outside a predetermined setting range is determined as abnormal data based on the average value between each coordinate of the obtained coordinate data. Calculation method.