JPH0248638A - Display device - Google Patents

Abstract

PURPOSE:To decrease a line defect failure by a simple constitution by providing an inspection terminal and a dummy connection terminal in parallel to input/ output terminal on one of input/output terminal providing parts and the other, respectively and narrowing the width of one of the inspection and the dummy connection terminals. CONSTITUTION:On an output terminal providing part 2a of a wiring board 2 of a flexible substrate, an output terminal 6 of a metallic wiring, and also, dummy connection terminals 9a, 9c, etc., being inspection connection terminals which are in parallel to the output terminal and connected by a terminal 9b are provided, and on an input terminal wiring part 3a of a glass substrate 3, an input terminal 4 and inspection terminals 12, 13 are provided in the same way, and the terminals 12, 13 are formed so that its width is narrower than that of the terminals 9a, 9b. In this state, when the terminals 4, 6 are shifted exceeding a standard and connected through a vertical thick film of Ni particles, etc., the terminal 13 is shifted from the terminal 9c and does not conduct at the time of energizing through pads 14, 16, and a line connection failure is inspected surely and satisfactorily. Accordingly, a line connection failure defect of a display device can be decreased by a simple constitution.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a display device in which a display panel and a wiring board are connected by a conductive film that conducts current only in the film thickness direction. The present invention relates to a display device having a function of detecting a connection state with a substrate.

[Prior Art] As shown in FIG. 5, a thin film transistor is used as an address display element and a matrix type liquid crystal display panel is used as a display panel in order to transmit an image signal to a flexible substrate 22 which is a wiring board. A drive device 28 is provided, as shown in FIG.
The structure is such that a part of the flexible substrate 22 and a part of the glass substrate 23 of the Marx-IJ type liquid crystal display panel are overlapped.

As shown in FIG. 7, the flexible substrate 22 includes:
The metal wiring vA (Sn plating + Cu) 26 which is an output terminal is arranged in the output terminal arrangement part 22a which is the upper side of the overlapping surface with the glass substrate 23, while the input terminal arrangement part which is the lower surface of the glass substrate 23 is arranged. A metal wiring (Ta+ITO) 24, which is an input terminal, is disposed at 23a.

The output terminal arranging part 22a and the input terminal arranging part 23a are composed of Ni particles 25 for conducting current only in the film thickness direction.
are connected by an anisotropic conductive film 27 containing
The metal wiring 26 and the metal wiring 24 are made of Ni particles 25...
It is energized by.

Then, the image signal from the driving device 28 is passed from the metal wiring 26 to the metal wiring 24 through the Ni particles 25, . . . , and the thin film transistor is activated to drive the liquid crystal.

[Problem to be solved by the invention]

However, in the conventional display device described above, the output terminal arrangement section 2
2a and the input terminal arrangement section 23a, the connection between the metal wiring 26 and the Ni particles 25... and the Ni particles 25
. . . and the metal wiring 24, the effective connection width necessary for good current conduction is determined, and the connection between the output terminal placement portion 22a and the input terminal placement portion 23a may be misaligned. In this case, the metal wiring 26 and the Ni particles 25...
. . and the connection between the Ni particles 25 . . . and the metal wiring 24 are narrower than the effective connection width.

Further, when manufacturing the flexible substrate 22 and the glass substrate 23, even if variations occur in the alignment precision of the output terminal placement portion 22a or the input terminal placement portion 23a, the alignment between the metal wiring 26 and the Ni particles 25... The connection and the connection between the Ni particles 25 . . . and the metal wiring 24 become narrower than the effective connection width.

In this way, if a connection is made with a connection width narrower than the effective connection width, the effective connection width may be out of specification. In this case, not only is the current supply from the metal wiring 26 to the metal wiring 24 through the Ni particles 25 . Since defects occur, the yield of the product decreases, resulting in a significant increase in manufacturing costs.

[Means to solve the problem]

In order to solve the above-mentioned problems, a display device according to the present invention has an input terminal arrangement part of a display panel provided with an input terminal for energizing a display element, and an output terminal provided at a position opposite to the input terminal. In a display device in which an output terminal arranging part of a wiring board provided is connected by a conductive film for conducting current only in the film thickness direction, either one of the input terminal arranging part and the output terminal arranging part. While multiple test terminals are provided on the
The other side is provided with a connection terminal for energizing the plurality of test terminals to each other through the conductive film, and these test terminals and connection terminals are arranged parallel to the input terminal and output terminal, and the input terminal Either the test terminal or the connection terminal is connected so that at least one test terminal and the connection terminal are disconnected when the terminal arrangement part and the output terminal arrangement part are connected in a state where the effective connection width is outside the standard. It is characterized by one side being narrower than the other.

[For production]

With the above configuration, by energizing the inspection terminals with each other using a tester, etc., and checking the energization state, it is possible to check whether the input terminal placement part and the output terminal placement part are connected misaligned, or to check the alignment accuracy during manufacturing. It is possible to inspect at the stage of the connection process whether or not the conduction of current from the input terminal to the output terminal through the conductive film is unstable or interrupted due to variations in the conductive film. Therefore, if you use the above-mentioned tester etc. to screen out those with poor current conductivity when connecting the input terminal placement part and the output terminal placement part, the connection between the conductive film and the input terminal or output terminal will be effective. Since it is possible to remove and leak connections that are narrower than the connection width as non-standard effective connection widths, it is possible to reduce line defects in each inspection process in the subsequent process, improve product yield, and ultimately It becomes possible to aim at cost reduction.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

The display device of this example uses a thin film transistor as an address display element and a matrix type liquid crystal display panel as a display panel.
As shown in the figure, a driving device 10 for transmitting an image signal is provided on a flexible substrate 2, which is a wiring board, and a part of this flexible substrate 2 and a glass substrate 3 of a matrix type liquid crystal display panel are provided. It has a structure in which some parts are overlapped.

As shown in FIG. 2(a), the flexible substrate 2 has metal wiring (Sn plating + Cu) which is an output terminal in the output terminal arrangement part 2a which is the overlapping surface with the glass substrate 3.
6 is arranged, and on the side of the metal wiring 6,
Dummy wirings 9a, 9b, and 9c, which are connection terminals, are connected and arranged in a substantially inverted U shape.

Further, as shown in FIG. 2(b), the glass substrate 3 has an input terminal disposed opposite to the metal wiring 6 in the input terminal arrangement portion 3a, which is the overlapping surface with the flexible substrate 2. A metal wiring (Ta+ITO) 4 which is a terminal is provided, and on the side thereof is a test terminal whose width is narrowed with the outer ends of the dummy wirings 9a and 9c forming a substantially inverted U shape as opposed arrangement standards. Dummy wirings 12 and 13 are provided. One dummy wiring 12 is the dummy wiring 9 described above.
The other dummy wiring 13 is placed opposite to the dummy wiring 9C.

Furthermore, the ends 12a-1 of these dummy wirings 12 and 13
3a is located outside the overlapping range with the flexible substrate 2, and pads 14 and 15 for detecting positional deviation are connected to these ends 12a and 13a.

Then, the output terminal arranging section 2a and the input terminal arranging section 3a
As shown in FIG. 3(a), the metal wiring 6 and the metal The wiring 4 is energized via the Ni particles 5..., and the dummy wiring 9a
-9C and the dummy wirings 12 and 13 are also energized via the Ni particles 5...

In the above configuration, in order to perform display, an image signal is first transmitted from the driving device 10, and this image signal is energized from the metal wiring 6 to the metal wiring A4 through the Ni particles 5, and operates the thin film transistor. This will drive the liquid crystal.

According to the above configuration, after the input terminal placement portion 3a and the output terminal placement portion 2a are bonded together by the anisotropic conductive film 7 containing Ni particles 5, the positional deviation detection pad 14
・Continuity can be checked during the connection process by applying a tester or the like to 15.

In the above continuity check, as shown in FIG. 3(b), if the input terminal placement portion 3a and the output terminal placement portion 2a are not misaligned, the image signal is Dummy wiring 12-.

Dummy wiring 9a″: Dummy wiring 9b Dummy wiring 9c!
: Dummy wiring 13'': Conductive through the path of positional deviation detection pad 15''.

On the other hand, as shown in FIG. 4(a), the flexible substrate 2
is connected with a shift in the direction of arrow A, the image signal is "positional deviation detection pad (4 dummy cotton distribution 122 (unstable)": dummy wiring 9a = dummy wiring 9b dummy wiring 9c Z (Disconnection) At least the dummy wiring 9C and the dummy wiring 13 are disconnected where conduction should be in the path between the dummy wiring 13 and the positional deviation detection pad 15. As a result, the connection between the dummy wiring 9C and the dummy wiring 13 becomes disconnected. It is possible to detect that the conduction state is unstable or disconnected, and to confirm that the effective connection width is out of specification.

Moreover, as shown in FIG. 4(b), the flexible substrate 2
is connected with a shift in the direction of arrow B, the image signal is "position shift detection pad 14!: dummy wiring 12
``: (disconnection)'':, dummy wiring 9a dummy wiring 9b dummy wiring 9c: (unstable) dummy wiring 13 2 positional deviation detection pad 15'' where conduction should be established between the dummy wiring 12 and the dummy wiring 9a At the very least, there will be no communication between them. As a result, it is possible to detect that the conduction state between the metal wirings 4 and 6 is unstable or disconnected, and to confirm that the effective connection width is out of specification.

In this way, by energizing the positional deviation detection pads 14 and 15 and checking the energization state, it is possible to detect whether the input terminal arrangement section 3a and the output terminal arrangement section 2a are connected misaligned, or when manufacturing. Metal alignment accuracy may vary.

It becomes possible to inspect at the stage of the connection process whether the current supply from the wiring 4 to the metal wiring 6 through the Ni particles 5 . . . is unstable or interrupted.

In this embodiment, the dummy wirings 12 and 13 and the positional deviation detection pads 14 and 15 are provided in the input terminal arrangement section 3a, but these may also be provided in the output terminal arrangement section 2a. , the extended dummy wirings 12 and 13 themselves may be used as positional deviation detection pads.

〔Effect of the invention〕

As described above, the display device according to the present invention includes an input terminal arrangement portion of a display panel provided with an input terminal for energizing a display element, and a wiring board provided with an output terminal at a position opposite to the input terminal. In a display device in which an output terminal arranging part is connected by a conductive film for conducting current only in the film thickness direction, a plurality of inspections are performed on either the input terminal arranging part or the output terminal arranging part. On one side, a terminal is provided, and on the other side, a connection terminal is provided for energizing the plurality of test terminals to each other through the above-mentioned conductive film, and these test terminals and connection terminals are arranged in parallel with the above-mentioned input terminal and output terminal. In addition, the inspection terminal and One of the connection terminals is formed narrower than the other.

This makes it possible to easily inspect for non-standard effective connection widths during the connection process, greatly improving connection reliability, and allowing defective products that occur during the connection process to be sent directly to subsequent processes. That will no longer be the case. Therefore, since the yield of products is improved, it is possible to reduce manufacturing costs.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention, in which FIG. 1 is a plan view showing the main parts of a display device, and FIG.
Figure a) is an explanatory diagram showing the arrangement positions of metal wiring and dummy wiring in the output terminal arrangement part, and figure (b) is an explanatory diagram showing the arrangement position of the metal wiring and dummy wiring in the input terminal arrangement part. , FIG. 3(a) is a longitudinal sectional front view showing the connecting part between the output terminal arranging part and the input terminal arranging part, and FIG. 3(b) shows the overlapping of the output terminal arranging part and the input terminal arranging part. FIGS. 4(a) and 4(b) are plan views showing a state in which the output terminal arranging part and the input terminal arranging part are overlaid with deviations from the standard of the effective connection width, respectively. It is. 5 to 7 show conventional examples.
The figure is a plan view showing the main parts of the display device, Figure 6 is a side view of the output terminal arrangement part and input terminal arrangement part superimposed, and Figure 7 is the output terminal arrangement part and the input terminal arrangement part. FIG. 2 is a flexible board (wiring board), 3 is a glass board,
2a is the output terminal arrangement part, 4 is the metal wiring (input terminal), 5
is Ni particle, 6 is metal wiring (output terminal), 7 is anisotropic conductive film, 9a, 9b, 9c are dummy wiring (connection terminal), 1
0 indicates driving devices 12 and 13 are dummy wirings (inspection terminals), 12a and 13a are end portions, and 14 and 15 are positional deviation detection pads. Figure (a)

Claims (1)

[Claims] 1. The input terminal arrangement part of the display panel, which is provided with an input terminal for energizing the display element, and the output terminal arrangement part of the wiring board, in which the output terminal is provided at a position opposite to the input terminal, have a film thickness. In a display device connected by a conductive film for supplying current only in one direction, a plurality of test terminals are provided in one of the input terminal arrangement part and the output terminal arrangement part, while the other is provided with a plurality of test terminals. A connection terminal is provided for energizing a plurality of test terminals to each other through a conductive film, and these test terminals and connection terminals are arranged parallel to the input terminal and output terminal, and are connected to the input terminal arrangement part. Either one of the test terminals and the connection terminal is wider than the other so that at least one test terminal and the connection terminal will be disconnected when the output terminal arrangement part is connected with the effective connection width outside the standard. A display device characterized by being formed narrowly.