JPH0347550B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a highly accurate pattern position recognition method.

(Prior Art) A conventional pattern recognition method will be explained with reference to FIG. In FIG. 1, 1 is a movable stage, 2 is a substrate, 3 is a pattern, 4 is a television camera for pattern recognition, 5 is a column, and 6 is an epi-illumination device. The pattern 3 formed on the surface of the substrate 2 is illuminated from the surface side of the substrate 2 by an epi-illumination device 6, photographed by a television camera for pattern recognition, converted into an electrical signal, and sent to a recognition device (not shown). Sent.

However, a conductor pattern such as a thick gold film formed on an alumina substrate reflects light and shines, making it difficult to distinguish between the alumina substrate and the conductor pattern when recognizing the pattern position using a recognition television camera. was difficult.

Another method is to form marks for pattern position recognition on the surface of the substrate using ink or the like that can be easily distinguished from the substrate, but in this method, pattern formation and recognition mark formation are performed in separate steps. Therefore, there was a drawback that the positional relationship between the recognition mark and the pattern could not be accurately obtained.

(Objective and Structure of the Invention) An object of the present invention is to provide a method for recognizing the position of a conductor pattern with good discrimination. A recognition mark is formed at a position that maintains the correct position with the pattern, and in subsequent processes that require pattern recognition, the position of the conductor pattern is recognized using the recognition mark as a position reference. Yes, this will be explained in detail below.

(Embodiment) FIG. 2 shows an embodiment of the present invention, in which 11 is a movable stage, 14 is a television camera for pattern recognition, 15 is a column, 16a is an epi-illumination device, 16b
17 is a transparent stage plate, 21 is an alumina substrate, and 22 is a conductor pattern. To operate this, the substrate 21 must be placed on the transparent stage plate 17.
The substrate 21 is placed on top of the substrate 21, and a transmission illumination device is used to shine light from the back side of the substrate, and a pattern recognition television camera supported by a support 15 on the front side of the substrate 21 is used to photograph the substrate. Alumina substrates used for thick film printing transmit light, but
Since the conductor pattern does not transmit light, it appears black and can be easily identified. Note that the substrate is not limited to an alumina substrate, and other materials may be used as long as they have light transmittance.

Further, as shown in FIG. 3, a mark 23a larger than the intended recognition mark is formed on the surface of the substrate 21 using a paste or the like having a low reflectance and easily distinguishable from the conductive pattern 22. Then the fourth
As shown in the figure, light is applied from the back side of the substrate, and the position of the conductor pattern 22 is recognized by using the pattern 22 as a black shadow. Using this recognition result, the mark 23a shown in FIG. 3 itself is shaped with a laser to form the intended recognition mark 23b. A display element or an IC is placed on the substrate 21 on which the conductor pattern 22 and the recognition mark 23b are formed in this way.
Conductor pattern position recognition when mounting a chip or the like or when performing wire bonding between the above element or chip and a conductor pattern is performed using a pattern position recognition device that uses only epi-illumination light as shown in Figure 1. It can be carried out. FIG. 5 shows how pattern recognition is actually performed using only epi-illumination. Even if the pattern 22 reflects light and is difficult to distinguish from the substrate 21, the pattern position can be easily and accurately determined using a pattern recognition mark that is shaped with a laser and maintains the correct positional relationship with the pattern. This makes it possible to accurately align the elements, chips, etc. when mounting them or performing wire bonding. Note that when shaping the mark 23a itself with a laser to form a pattern recognition mark, it is necessary to recognize the pattern using light from the back side of the board. By performing pattern recognition using light, deviations in the vertical, horizontal, and rotational directions can be reduced.

(Effects of the Invention) The present invention performs pattern recognition using a recognition mark that accurately shows the positional relationship with the pattern, so it can be used for thick film multilayer printing or mounting a display element that requires accurate positional relationship with the pattern. Can be applied to alignment of wire bonding, laser trimming, etc.

[Brief explanation of drawings]

FIG. 1 shows a conventional pattern recognition method, FIG. 2 shows a first embodiment of the present invention, and FIGS. 3, 4, and 5 show a second embodiment of the present invention. 11...Movable stage, 21...Substrate, 22...
...Pattern, 14...Television camera for pattern recognition, 15...Strut, 16a...Epi-illumination device, 1
6b...transmission illumination device, 17...transparent stage plate, 23a...recognition mark formed with easily recognizable ink (before shaping), 23b...recognition mark shaped by laser or the like on 23a.

Claims (1)

[Claims] 1. For a light-transmissive substrate on which a conductive pattern made of a material with high reflectance such as a thick gold film and a mark made of a material with low reflectance are formed, light is irradiated from the back side of the substrate, and The conductor pattern is read from the front side, and the mark itself is shaped according to the recognition result of the conductor pattern position, thereby forming a recognition mark that maintains an accurate positional relationship with the conductor pattern. In the process requiring pattern position recognition, the position of the conductive pattern is recognized by irradiating light from the front surface of the substrate and reading the pattern from the front surface of the substrate, using the recognition mark as a position reference. A pattern position recognition method.