JPH0213948B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a method for forming a conductor layer, and in particular, the adhesion strength of a thick film conductor layer such as a drive circuit portion of a contact type image sensor is The present invention relates to a method for preventing deterioration during deposition of an asilicon layer.

[Prior art]

Amorphous semiconductors, which have been rapidly put into practical use in recent years, have maximized their advantages, such as being easy to grow into large areas, having a large degree of freedom in composition, and being able to control electrical and optical properties over a wide range. Attempts are being made to utilize this technology and apply it to various fields.

One such approach is to construct a contact type image sensor in which the drive circuit section is made up of a thick film circuit, and the sensor section is made up of an amorphous semiconductor such as amorphous hydrogenated silicon.

Thick film circuits have the advantages of being inexpensive with fewer manufacturing steps, resistant to ambient conditions, and able to withstand large amounts of power, and are desired to coexist with amorphous semiconductors. As a result, the following inconveniences may occur.

Since the thick film forming process includes a firing process in a high temperature range, the amorphous semiconductor layer is usually formed after the thick film circuit pattern is formed.

For example, after forming a drive circuit part using a thick gold film pattern (gold pattern), an amorphous hydrogenated silicon layer as a sensor part is formed using plasma plasma.
When depositing by CVD method etc., gas plasma such as silane or hydrogen may damage the film quality of the gold pattern, or the gas plasma may intervene between the gold pattern and the ceramic substrate. The adhesion strength of the gold pattern to the ceramic substrate decreases. Therefore, in the wire bonding process for mounting a semiconductor chip on this thick film circuit (gold pattern), peeling of the film frequently occurs, which causes a decrease in yield.

[Purpose of the invention]

The present invention was made in view of the above circumstances, and
The purpose is to form a good thick film pattern that will not peel off due to surrounding environmental conditions, and to improve the yield of wiring boards.

[Structure of the invention]

In order to achieve the above object, the present invention is characterized in that a normal thick film pattern and a metal organic made of a noble metal are superimposed to form a double-structured conductor pattern.

That is, in this invention, a conductor pattern that is resistant to changes in the surrounding environment can be created by adopting a structure in which a metallo-organic pattern made of noble metal is superimposed on a thick film pattern, or a structure in which a thick film pattern is superimposed on a metallo-organic pattern. This is what we are trying to provide.

〔Example〕

Hereinafter, the present invention will be described in detail based on examples of the present invention.

First, gold paste is printed on a 96% alumina substrate 1 using a specified screen of 250 meshes, dried, and then fired in a firing furnace at 870 to 930°C for a specified period of time as shown in Figure 1. Like, film thickness 4~
A thick gold film pattern 2 of 6 μm is formed. In addition,
A glazed portion 4 is previously formed on the sensor forming portion on the alumina substrate 1 in order to make the surface smooth.

Next, using a screen having the same pattern as the above-mentioned screen, metal organic gold manufactured by Engelhard, which is commercially available under the trade name A3725, was printed, dried, and then fired in a firing furnace at 930 ° C for a predetermined time. As shown in Figure 2, the film thickness is 1000.
A metallo-organic gold pattern 3 of .ANG. is formed.

In this way, a two-layer conductor layer in which the metallo-organic gold pattern 3 is superimposed on the gold thick film pattern 2 is formed, and further predetermined processing is performed to form a drive circuit section A made of a thick film circuit. form.

After this, the sensor section is formed. First, a chromium thin film with a thickness of 4000 Å is deposited on the glazed portion 4 on the alumina substrate by vapor deposition, and then a chromium electrode 5 having a predetermined shape as a lower electrode is patterned by photolithography.

Furthermore, as shown in Figure 3, plasma CVD
An amorphous hydrogenated silicon layer 6 is deposited as a photoconductor layer by a method. In this step, the amorphous hydrogenated silicon layer 5 is not deposited on unnecessary portions by placing a plate-shaped body 7 of a predetermined shape on the substrate as a mask. Note that the thickness of this amorphous hydrogenated silicon layer is 1 μm.

Next, after removing the plate-like body 7, a metal mask (not shown) having a predetermined shape is formed as shown in FIG.
An indium tin oxide electrode 8 serving as an upper electrode is deposited to a thickness of about 0.1 μm via the indium tin oxide electrode 8 .

Finally, the contact image sensor is completed by completing the connection between the drive circuit section formed by the thick film circuit and the sensor section by wire bonding or the like.

In this way, by adopting a structure in which the thick gold film pattern 2 is protected by the metallo-organic gold pattern 3, the film thickness can be prevented from increasing significantly.
This thick film circuit uses silane,
Even in a gas plasma atmosphere such as hydrogen, a good thick film can be maintained without being damaged. Therefore, no peeling of the film occurs during the wire bonding process, and the manufacturing yield as a contact type image sensor is greatly improved.

In addition, in the examples, a metallo-organic gold pattern was formed on a thick gold film pattern.
Conversely, a structure in which a thick gold film pattern is formed on a metallo-organic gold pattern is also effective. In other words, the metallo-organic layer improves its adhesion to the substrate not only when it is formed on a thick film pattern, but also when it is formed under the thick film pattern, making it a good conductor that does not easily peel off. You can get the pattern.

Further, the thick film pattern is not necessarily limited to gold, and similar effects can be obtained when other metals such as silver and palladium are used. In this case, if an etching step is involved in forming the pattern, it is desirable to use a metal organic of the same type of metal from the viewpoint of etching workability, but it is not necessarily necessary to use the same type of metal. That is,
A structure in which a thick silver film pattern is protected with metal organic palladium is also effective.

Furthermore, the metallo-organic layer may be formed not only by screen printing, but also by brushing, spraying, or the like.

In addition, this method is not limited to the formation of contact image sensors, but is effective for a wide range of semiconductor device manufacturing, and is particularly effective when thick film wiring boards are exposed to a gas plasma atmosphere in subsequent processes. It is.

〔Effect of the invention〕

As explained above, according to the present invention,
Since the conductor pattern is formed with a two-layer structure of a normal thick film pattern and a metallo-organic pattern, it has good adhesion that will not be damaged even in the surrounding environmental conditions during the subsequent manufacturing process. Not only can a conductor layer be obtained, but also the yield of the entire device can be improved.

[Brief explanation of drawings]

1 to 4 are schematic diagrams showing the manufacturing process of a contact type image sensor based on the method of forming a conductor layer according to an embodiment of the present invention. 1... Alumina substrate, 2... Gold thick film pattern, 3... Metalloorganic gold pattern, 4...
...glazed part, 5...chromium electrode,
6... Amorphous hydrogenated silicon layer, 7... Plate body, 8... Indium tin oxide electrode, A... Drive circuit section.

Claims (1)

[Claims] 1. A method for forming a conductor layer on a substrate, comprising: a thick film conductor layer forming step for forming a thick film conductor layer; and a metallo-organic layer forming step for forming a metallo-organic layer made of a noble metal. A method for forming a conductor layer, comprising: forming a conductor layer having a two-layer structure in which the thick film conductor layer and the metallo-organic layer are laminated. 2. The method of forming a conductor layer according to claim 1, wherein the metalloorganic layer is formed after the thick film conductor layer is formed. 3. The method of forming a conductor layer according to claim 1, wherein the metalloorganic layer is formed prior to the formation of the thick film conductor layer.