JPH04241325A - Electrode wiring substrate - Google Patents

Abstract

PURPOSE:To lower connection resistance and to allow dealing with a trend toward larger substrates by adopting the structure which allows the larger taking of the junctures between external upper electrode films and upper electrode wirings. CONSTITUTION:The structure to interpose tantalum electrode wirings 2 and conductive film pieces 4 having etching selectivity under the tantalum electrode wirings 2 patterned on a glass substrate 1 is adopted. Etching is ended by the conductive pieces 4. The exposed parts 40 of the conductive film pieces 4 exposed at this time and the etching surfaces 20 of the tantalum electrode wirings 2 are effectively utilized as the junctures C.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an electrode substrate having metal electrode wiring such as tantalum electrode wiring, and more specifically, the present invention is characterized by a connecting portion electrically connected to another upper layer electrode film or upper layer electrode wiring. This invention relates to an electrode wiring board.

0002

2. Description of the Related Art Dry etching can be considered as one of the methods for producing a connection portion electrically connected to another upper layer electrode film or upper layer electrode wire on a tantalum electrode wire covered with tantalum oxide. However, according to this method, it is difficult to obtain etching selectivity between tantalum oxide and tantalum, so it is necessary to perform etching through the tantalum oxide layer 3 to the bottom of the tantalum electrode wiring 2, as shown in FIG. The etching was terminated when the bottom edge was reached, and the etched surface 20 formed at this time, indicated by diagonal lines in the figure, was obtained as the connecting portion C.

0003

[Problems to be Solved by the Invention] According to the connection part C having the above structure, since the surface area of the connection part C is small, the connection area with the external upper layer electrode film or upper layer electrode wiring becomes small, and the connection resistance increases. The disadvantage is that it gets bigger.

In order to eliminate this drawback, as shown in FIG. 6, the etching is completed in the middle of the tantalum electrode wiring 2, and the remaining bottom portion 21 is then removed from the etched surface 2.
It may be used as a connection part C in combination with 0.

However, as mentioned above, it is difficult to obtain etching selectivity between tantalum oxide and tantalum, so in order to successfully finish etching in the middle of the tantalum electrode wiring 2, it is necessary to precisely control the etching conditions. be. In particular, when targeting a substrate with a large area, it is difficult to put it into practical use because the entire substrate must be etched uniformly and etching conditions must be controlled more precisely.

[0006] The present invention eliminates the drawbacks of the prior art, and aims to provide an electrode wiring board that can expand the connection area of the connection part and can also be used for large-sized boards.

[0007]

[Means for Solving the Problems] The electrode wiring board of the present invention is an electrode board having metal electrode wiring, the upper layer of the metal electrode wiring is covered with an insulating film, and the metal electrode wiring and the electrode substrate or the lower layer are covered with an insulating film. A conductive film piece having etching selectivity with the metal electrode wiring is provided between the film and a part of the conductive film piece and the metal that are exposed by etching the insulating film layer and the metal electrode wiring layer. The etched surface of the electrode wiring serves as a connection part that is electrically connected to another upper layer electrode film or upper layer electrode wiring, thereby achieving the above object.

Further, the electrode wiring board of the present invention is an electrode board having metal electrode wiring, the upper layer of the metal electrode wiring is covered with an insulating film, and between the insulating film and the metal electrode wiring, A conductive film piece having etching selectivity with respect to the insulating film is provided, and a part of the conductive film piece exposed by etching the insulating film layer is electrically connected to another upper layer electrode film or upper layer electrode wiring. The above object is thereby achieved.

[0009]

[Function] As described above, when a conductive film piece having etching selectivity is interposed between the metal electrode wiring or the insulating film, the progress of etching is stopped by the conductive film piece, thereby increasing the margin against over-etching. That is, etching can be easily made uniform. Furthermore, since the conductive film piece can be used as a connection part, the connection area can be increased.

0010

[Examples] Examples of the present invention will be described below.

FIG. 1 shows an electrode wiring board according to an embodiment of the present invention, and the electrode wiring board is manufactured according to the following manufacturing procedure.

First, an Al layer is laminated as a conductive film layer at a predetermined location on the glass substrate 1 by a sputtering method, and then this Al layer is patterned to form a conductive film piece 4.

[0013] The conductive film layer is not limited to Al, but may also include Cr, ITO (Indum TinOxi), etc.
A metal layer such as de) may also be used. However, in this example, the following tantalum electrode wiring 2 is used as the metal electrode wiring.
Since this method uses the tantalum electrode wiring 2, it is limited to a metal layer that has etching selectivity with respect to the tantalum electrode wiring 2.

Next, a tantalum layer is deposited on the glass substrate 1 by sputtering so as to cover the conductive film piece 4, and the tantalum layer is patterned to form the tantalum electrode wiring 2. Next, the tantalum electrode wiring 2 is anodized to form a tantalum oxide layer 3 as an insulating film on the upper layer of the tantalum electrode wiring 2. Note that the tantalum oxide layer 3 may be created using a sputtering method.

Next, from this state, C is added as a reaction gas.
The tantalum oxide layer 3 and the tantalum electrode wiring 2 are etched by a dry etching method using F4 and O2, and a connection portion C is formed at the etched location. When such a conductive film piece 4 is provided, the progress of etching is stopped at this position. Therefore, a part of the conductive film piece 4 is exposed by etching, and in this embodiment, the exposed part 40 and the etched surface 20 of the tantalum electrode wiring 2 constitute a connecting part C.

[0016] Such a connecting portion C has the following advantages.

(2) Since the exposed portion 40 is secured, the connection area can be increased compared to the conventional example shown in FIG. 5, and therefore the connection resistance can be reduced.

(2) Since the conductive film piece 4 has etching selectivity with respect to the tantalum electrode wiring 2, the end point of etching can be easily obtained. Therefore, uniform etching can be achieved and large substrates can be easily handled.

FIG. 2 shows another embodiment of the invention,
In this embodiment, a conductive film piece 4 is formed on the tantalum electrode wiring 2, and a tantalum oxide layer 3 is formed on the tantalum electrode wiring 2 by sputtering so as to cover the conductive film piece 4.

The conductive film piece 4 has etching selectivity with respect to the tantalum oxide layer 3, and the connection portion C is obtained by etching the tantalum oxide layer 3. That is, in this embodiment, the exposed portion 40 of the conductive film piece 4 constitutes the connection portion C. Note that the insulating layer is not limited to the tantalum oxide layer 3, but may be any material that has etching selectivity with respect to the conductive film piece 4, and various combinations are possible.

FIG. 3 shows another embodiment of the present invention. In this embodiment, the broken line portion shown in the figure is removed by etching, whereby the etched surface 20 of the tantalum electrode wiring 2 and the conductive film piece are removed. Exposed portion 4 corresponding to one side of 4
The configuration is such that the connection part C is a combination of 0's. According to this embodiment, since the etching area is relatively large and the etching shape is simple, etching becomes easier and the connection area can be further increased.

In addition, the thickness of the conductive film piece 4 can be freely set due to the ease of etching and its laminated structure.
When forming an upper electrode film or an electrode wiring film to be connected via the layer, no step breakage occurs due to a step difference. Therefore, production stability and efficiency can be achieved.

FIG. 4 also shows another embodiment of the present invention, in which a conductive wire is placed at one end of the tantalum electrode wiring 2 so that the other end is located on the glass substrate 1. The membrane piece 4 is formed, and the exposed portion 40 exposed by etching is used as the connection portion C.

[0024]

According to the present invention, a conductive film piece having etching selectivity with respect to the metal electrode wiring film or insulating film is formed above or below the metal electrode wiring. The progress of etching is stopped at the position. Therefore, since the margin against over-etching can be increased, even in the case of a large substrate, etching can be performed uniformly. Therefore, it is possible to realize a large electrode wiring board, which has been difficult in the past.

In addition, since the connection area of the connection portion with the external upper layer electrode film or upper layer electrode wiring can be increased, there is an advantage that connection resistance can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a drawing showing one embodiment of the present invention.

FIG. 2 is a drawing showing another embodiment of the present invention.

FIG. 3 is a drawing showing another embodiment of the present invention.

FIG. 4 is a drawing showing another embodiment of the present invention.

FIG. 5 is a drawing showing a conventional example.

FIG. 6 is a drawing showing another conventional example.

[Explanation of symbols]

1 Glass substrate 2 Tantalum electrode wiring 20 Etched surface 21 Bottom part 3 Tantalum oxide layer 4 Conductive film piece 40 Exposed part C Connection part

Claims (2)

[Claims] Claim 1: An electrode substrate having metal electrode wiring, comprising:
The upper layer of the metal electrode wiring is covered with an insulating film, and a conductive film piece having etching selectivity with the metal electrode wiring is provided between the metal electrode wiring and the electrode substrate or the lower layer film, and the insulating film layer and a part of the conductive film piece exposed by etching the metal electrode wiring layer and the etched surface of the metal electrode wiring as a connection part that is electrically connected to another upper layer electrode film or upper layer electrode wiring. Electrode wiring board. 2. An electrode substrate having metal electrode wiring,
The upper layer of the metal electrode wiring is covered with an insulating film, and a conductive film piece having etching selectivity with respect to the insulating film is provided between the insulating film and the metal electrode wiring, and the insulating film layer is etched. An electrode wiring board in which a part of the exposed conductive film piece is a connection part electrically connected to another upper layer electrode film or upper layer electrode wiring.