JPS6239020A - Wire bonding device - Google Patents

Abstract

PURPOSE:To fix the relative positions of a substrate and bonding head stably with high precision by a method wherein a lighting equipment is arranged on a heater block side to irradiate an identification mark forming position with transmitted light from backside of the substrate. CONSTITUTION:A vertical through hole 16 is formed into a heater block 4 immediately below a monitor scope 3 while an optical fiber head 18 of a lighting equipment 17 is inserted upward into the vertical hole 16. In order to perform the wire bonding process, a substrate 11 is loaded upon the heater block 4 so that an identification mark A formed on the surface of substrate 11 may be positioned almost on the hole 16 to receive the transmitted light irradiating the backside of substrate 11 from the optical fiber head 18 into the monitor scope 3 for position control based on the pattern identification.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a wire bonding device, and more specifically, a monitor scope provided on the bonding head side monitors a positioning recognition mark formed on the surface of a substrate. In particular, the present invention relates to a wire bonding device characterized by a means for irradiating a recognition mark.

<Prior Art> FIG. 5 shows the basic configuration of a wire bonding apparatus to which the present invention is directed.

This device is equipped with a bonding head 2 and a monitor scope 3 on an XY table 1 that can be moved and adjusted in a horizontal plane by a pair of motors Mx and My, and is formed on the surface of a substrate loaded on a heater block 4 that is fixed in position. The image signal from the monitor scope 3 is transmitted to the pattern recognition unit 6 via the camera control unit 5, and pattern recognition processing is performed according to the procedure stored in the microcomputer 7. While displaying the results on monitor TV 8,
Motor MX via control circuit 9 and motor drive circuit 10
, My is configured to position the bonding head 2 in the horizontal direction with respect to the substrate on the heater block 4.

Conventionally, as shown in FIG. 6, a minute recognition mark A (generally a cross shape is used) formed on the surface of the substrate 11 on the heater block 4 by etching or the like is monitored with a monitor scope 3. To do this, a configuration has been adopted in which light from an illumination lamp 12.degree. 12 provided above the substrate 11 is irradiated onto the mark forming location, and the reflected light from the surface of the substrate 11 is taken into the monitor scope 3.

<Problems to be Solved by the Invention> L7 However, 1. The conventional example having such a configuration has the following problems.

In the means for monitoring the reflected light from the substrate 11 as described above, the clarity of the image captured by the monitor scope 3 changes greatly due to changes in illuminance due to voltage fluctuations of the illumination lamps 12, 12, changes in the direction of illumination, etc. Easy, based on this 2
In some cases, the converted image signal changes significantly, making it difficult to perform pattern recognition stably.

The present invention aims to solve the above-mentioned problems found in conventional means by improving the illumination means.

Means for Solving the Problems> In order to achieve the above object, the present invention has a configuration in which an illumination device that can irradiate light from below the substrate to the location where the recognition mark is formed is provided on the heater block side. .

Since the substrate is made of thin ceramic, it has some degree of light transmission, and if light of an appropriate intensity is irradiated from below, the recognition mark can be clearly seen by the light transmitted to the substrate surface. It can be captured as an image with great contrast.

Moreover, even if the luminous intensity of the irradiated light changes somewhat, the image produced by this transmitted light does not show any change in contrast, and a clear image is always obtained.

<Example> Below, the present invention will be described in detail based on an example shown in the drawings.

FIGS. 1 and 2 show an example of a characteristic component of the present invention.

In this example, the substrate 11 includes a heating resistor 13 and an I
A thermal printing head is shown that includes a C-chip 14 (only one is shown in the figure). The heater block 4 is made of a metal material such as stainless steel, and has an electric heater 15 inserted therein.

A hole 16 that vertically penetrates between the heater block 4 is formed directly below the monitor scope 3, and an optical fiber head 18, which is an example of a lighting device 17, is inserted into this hole 16 from below. There is.

Note that the light source is placed in a thermally safe location.

During the wire bonding process, the substrate 11 is loaded onto the heater block 4 so that the recognition mark A formed on the surface of the substrate 11 is positioned above the hole 16, and the substrate 11 is exposed from the optical fiber head 18. The light passing through the light irradiated onto the lower surface is taken into the monitor scope 3, and positioning control based on pattern recognition is performed as described above.

<Another Example 1> Fig. 3 shows a case where a heat-resistant and transparent material such as quartz glass is used for the heater block 4. In this case, a hole 19 extending almost to the top surface of the heater block 4 is formed from the bottom surface. , an optical fiber head 18 is inserted into this hole 19.

If the surface portion of the heater block 4 is continuous even above the hole 19 in this way, the heat distribution on the surface portion can be maintained uniformly.

Embodiment 2 This example shows a case where a general optical system is used for the illumination device 17. Light from a light source located below (not shown) is focused by a lens 20, and The light is irradiated onto the lower surface of the substrate 11 through the.

<Effects of the Invention> As described above, according to the present invention, the illumination device irradiates light onto the recognition mark formation location from below the substrate and monitors the transmitted light to the surface of the substrate. The recognition mark can always be captured as a clear image even when the light intensity or angle changes slightly, and as a result, pattern recognition can be performed well and the relative positioning of the board and bonding head can be stably and It can now be done with high precision.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of a main part of a wire bonding apparatus according to the present invention, FIG. 2 is a longitudinal sectional front view thereof, FIG. 3 is a longitudinal sectional front view showing another embodiment of the main part, and FIG. FIG. 5 is a side view schematically showing the basic structure of the wire bonding device, and FIG. 6 is a front view showing the main portion of a conventional example. A...Recognition mark, 3...Monitor scope, 4...Heater block, 11...
・Substrate, 1 day...Optical fiber head, 20...
・Lens applicant population - Company representative Patent attorney Oka 1) Kazuhide Figure 1

Claims (2)

[Claims] (1) The recognition mark formed on the surface of the substrate loaded on the heater block is monitored with a monitor scope provided on the bonding head side, and the relative position of the substrate and bonding head is corrected based on the pattern recognition results. A wire bonding apparatus configured to control the wire bonding apparatus, wherein an illumination device is provided on the heater block side and can irradiate a recognition mark formation location from below the substrate. (2) The wire bonding device according to claim (1), wherein the lighting device uses an optical fiber.