JP3255374B2 - Transfer substrate and transfer pattern forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer substrate and a method for forming a transfer pattern. And a method for forming a transfer pattern using the same.

[0002]

2. Description of the Related Art Conventionally, wiring and circuit patterns on a printed circuit board are formed by resist-patterning a copper thin film formed on a polyimide film or a glass epoxy substrate by using a photolithography method, and then performing etching or through-hole plating. It is formed by this.

In addition, resist patterning is performed by using an offset printing method instead of a photolithography method, and a wiring pattern is formed by printing a conductive paste by a screen printing method.

Further, a single-layer metal wiring pattern can be formed according to a full additive method, a pattern plating transfer method (FPC, etc.), etc., in addition to the above-mentioned method using etching.

However, except for the pattern plating transfer method, a complicated photolithography step is usually required. For example, in the formation of a substrate having a structure in which patterns are laminated only in the upper surface direction of the substrate, such as a surface laminar circuit (SLC), the lowermost metal film is patterned → an insulating layer is applied → a through hole is formed → electroless plating → electrolytic plating → plating Photolithography is used for patterning a metal film and forming a through hole by repeating film patterning → coating of an insulating layer.

[0006] Therefore, high throughput of the printed circuit board,
In order to reduce the cost, the photolithography method described above is replaced with a printing method. However, the conventional method of forming a coating film of an insulator such as polyimide by printing is limited to the formation of a large-area pattern, as in an example in which a flexographic printing method is used for coating an alignment film of an LCD panel. It is not used to form On the other hand, as for pattern transfer of a metal part, a plating transfer method of a wiring pattern is used for manufacturing a flexible printed circuit board or the like.

Here, it is possible to produce a printed circuit board by a combination of the above methods, but the insulating portion and the conductive portion are in close contact with each other in the metal pattern layer and the through-hole layer of the printed circuit board, and within the same plane in each layer. It is required that the insulating portion and the conductive wiring pattern portion coexist, and it is difficult to form a multilayer printed board by the above printing method alone.

[0008]

In order to solve the above problems, an electrodeposition transfer method has recently been developed as a method for forming a high-precision fine pattern on a workpiece. In the conventional electrodeposition transfer method, an insulative portion formed in a predetermined pattern on a conductive substrate is provided, and the electrodeposited material such as a metal or an organic substance is deposited only on the exposed conductive portion. Substrate is used. Then, a pattern made of the electrodeposited substance deposited and formed on the transfer substrate is transferred onto a workpiece through an adhesive layer to form a fine pattern.

However, it is easy to deposit a single electrodeposited material on the transfer substrate used in the conventional electrodeposition transfer method as described above, but depending on the pattern shape, different types of electrodeposited materials can be used together. It is impossible to deposit in a plane.
For example, when an electrodeposited substance A is to be pattern-formed on the peripheral solid part and an electrodeposited substance B is to be patterned on the island part located at the center of the peripheral solid part via the separation area, a lead electrode connected to the island part is formed. There is a problem that can not be.

The present invention has been made in view of such circumstances, and enables various kinds of electrodeposited substances to be electrodeposited on the same plane with high precision without being restricted by the pattern shape and arrangement. An object of the present invention is to provide a transfer substrate having high durability and a transfer pattern forming method using such a transfer substrate.

[0011]

In order to achieve the above object, the transfer substrate of the present invention is insulated and separated from the substrate by an insulating portion on the substrate, and is substantially flush with the substrate. It has two or more conductive parts formed and two or more lead electrodes, and each of the conductive parts has a predetermined pattern and is electrically connected to any of the lead electrodes, and at least one of the conductive parts One is configured to be electrically connected to the lead electrode via a conductive layer provided in the insulating portion, and the conductive portion is electrically independent for each lead electrode unit.

Further, the transfer pattern forming method of the present invention uses the above-described transfer substrate, deposits a desired electrodeposited substance on a conductive portion for each lead electrode of the transfer substrate, and thereafter,
The electrodeposition material was transferred to a transfer target.

[0013]

In the transfer substrate according to the present invention, two or more conductive portions formed so as to form substantially the same plane are insulated and separated via an insulating portion and are electrically connected to one of the two or more lead electrodes. Is electrically connected to the lead electrode via the conductive layer provided in the insulating portion, so that the conductive portion is electrically connected to each lead electrode without being restricted by the connection between the conductive portion and the lead electrode. It is possible to deposit a desired electrodeposited substance on the conductive portion for each lead electrode. Then, after a desired electrodeposition substance is deposited on the conductive portion by using such a transfer substrate, the electrodeposition substance can be collectively transferred to the transfer target.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view showing an example of the transfer substrate of the present invention, and FIG. 2 is a plan view of the transfer substrate II shown in FIG.
FIG. 2 is a sectional view taken along line II. 1 and 2, a transfer substrate 1 includes a substrate 2, a conductive portion 4 insulated and separated from the substrate 2 via an insulating portion 3, and a lead electrode 5.

The conductive portion 4 includes a conductive portion 4a having an island pattern shape and a conductive portion 4b existing around the conductive portion 4a via an isolation area 8.
And the conductive portion 4b form substantially the same plane. Conductive part 4a
Is connected to a conductive layer 6a formed inside the insulating portion 3 via a connecting portion 7a, and the conductive portion 4b is connected to a conductive layer 6b also formed inside the insulating portion 3 via a connecting portion 7b. One end of the conductive layer 6a is a lead electrode 5a, and one end of the conductive layer 6b is a lead electrode 5b. Therefore, the conductive portions 4a and 4b are connected to the lead electrodes 5a and 5b, respectively, and the conductive portions 4a and 4b are electrically independent for each lead electrode 5a and 5b. Therefore, for each lead electrode 5a, 5b,
That is, electrodeposition can be selectively and independently performed for each of the conductive portions 4a and 4b. Therefore, it is possible to electrodeposit different types of electrodeposition materials on the conductive portions 4a and 4b.

Substrate 2 used for transfer substrate 1 as described above
Examples thereof include a conductive metal substrate such as stainless steel and copper, and a substrate provided with a thin film made of a conductive material such as metal, tin oxide, indium tin oxide, and carbon on the surface of various nonconductive substrates. .

Examples of the material constituting the insulating portion 3 include butadiene rubber-based, polyisoprene rubber-based and polyimide-based insulating organic materials, silicon oxide, silicon nitride, and metal anodic oxide.

Conductive parts 4a, 4b, lead electrodes 5a, 5
b, the conductive layers 6a, 6b and the connecting portions 7a, 7b can be formed by means such as electroless plating, electroplating, vacuum deposition, sputtering, plating pattern transfer, or a combination of these means. If necessary, the conductive portions 4a and 4b may be subjected to a surface treatment so that the electrodeposited material electrodeposited on the conductive portions 4a and 4b is easily transferred to a transfer target at the time of transfer described later. Good. This surface treatment can be performed, for example, when the electrodeposition material is a metal such as copper plating, by selectively applying a metal plating of nickel, chromium, or the like having a high surface oxidizing property only to the conductive portion on which the metal is to be electrodeposited. it can. The same applies when the electrodeposition material is an organic substance.

Next, an example of manufacturing the transfer substrate of the present invention shown in FIGS. 1 and 2 will be described with reference to FIGS. First, an insulating film 3 is formed on a substrate 2 having a conductive layer 6a on the surface, and a through hole 11 is formed at a predetermined location (a location where a connecting portion 7a will be formed later) (FIG. 3A). Next, the conductive film 6a is used as an electrode, and metal plating is applied to the entire surface except for one end of the conductive film 6a to be the lead electrode 5a, thereby filling the through hole 11 with a conductive metal to form the connection portion 7a. (FIG. 3 (B)).

Next, a coating solution containing a hydrophilic resin and a metal compound serving as a catalyst for electroless plating is applied to the entire surface of the insulating film 3 and the connecting portion 7a, and the electroless plating solution is brought into contact with this coating layer. By doing so, a metal is deposited to form a conductive layer 6b (FIG. 3C). The conductive layer 6b
The layer thickness can be adjusted by further performing electrolytic plating on the entire surface as necessary.

Next, a photoresist is applied on the conductive layer 6b, and then exposed and developed through a mask having a predetermined shape to form a photoresist layer 12 (FIG. 3).
(D)). Then, the conductive layer 6b is etched using the photoresist layer 12 as a mask (FIG. 3E).

After that, the insulating film 3 is formed on the conductive layer 6b, and the insulating film 3 is formed at a predetermined position (a position where the connecting portions 7a and 7b are formed later).
Then, a through hole 13 is formed (FIG. 4A). next,
Conductive film 6b serving as electrode and conductive film 6 serving as lead electrode 5b
Metal plating is applied to the entire surface except for one end of b, thereby filling the through holes 13 with a conductive metal to form the connection portions 7a and 7b (FIG. 4B).

Next, a coating solution containing a hydrophilic resin and a metal compound serving as a catalyst for electroless plating is applied to the entire surface of the insulating film 3 and the connecting portions 7a and 7b. Are brought into contact with each other to deposit metal, and if necessary, the entire surface is subjected to electrolytic plating to adjust the film thickness, thereby forming the conductive portion 4 (FIG. 4C).

Next, a photoresist is applied on the conductive portion 4 and then exposed and developed through a mask having a predetermined shape to form a photoresist layer 14 (FIG. 4D).
Then, using the photoresist layer 14 as a mask, the conductive portion 4 is etched to form a conductive portion 4a having an island pattern shape and an isolation area 8 around the conductive portion 4a.
The conductive part 4b existing through the step is formed. (FIG. 4
(E)).

Here, the width of the separation area 8 is determined by the conductive portion 4a.
It is necessary to set according to the electrodeposition material to be electrodeposited on the conductive portion 4b. FIG. 5 is a cross-sectional view showing an electrodeposition pattern grown on the conductive portions 4a and 4b. Since the electrodeposition pattern grows substantially isotropically in the horizontal direction as well as in the vertical direction, the width of the separation area 8 is reduced. It is necessary to consider the growth amount of the electrodeposited material in the lateral direction. For example, when the electrodeposited materials to be electrodeposited on the conductive portion 4a and the conductive portion 4b are metal plating of the same or different kind, it is necessary to avoid contact between the electrodeposition patterns, and The width of the separation area 8 is set wider in advance so that a gap remains between the electrodeposition patterns even when the substance grows. Further, when one or both of the electrodeposited materials electrodeposited on the conductive portion 4a and the conductive portion 4b are insulating materials, there is no problem even if the electrodeposited patterns contact each other.
The electrodeposition material can be densely filled in the same plane as in the illustrated example. Such a close-packing method can be applied particularly effectively when, for example, a wiring layer of a multilayer wiring board is manufactured only by a repetitive transfer operation.

The transfer substrate 1 includes lead electrodes 5a,
Reference numeral 5b denotes a separated electrode-separated multilayer substrate, but the transfer substrate of the present invention is not limited to this. For example, the substrate obtained in the stage of FIG. 3E is also included in the transfer substrate of the present invention. That is, in FIG. 3E, the conductive layer 6a and the conductive layer 6b connected to the lead electrode 5a via the connection portion 7a (the central conductive layer 6 in the illustrated example).
b) corresponds to the conductive portion 4a having the island pattern shape in FIG. 1, and another conductive layer 6b (the conductive layers 6b at both ends in the illustrated example) is provided around the conductive portion 4a via the separation area in FIG. It corresponds to the existing conductive part 4b. In this case, the lead electrode 5a is connected to the conductive portion 4a (the central conductive layer 6b).
However, the other lead electrode 5b and the conductive portion 4b (the rightmost conductive layer 6b) are not separated from each other,
Uses a common plane.

FIG. 6 is a plan view showing another example of the transfer substrate of the present invention, and FIG. 7 is a sectional view taken along line VII-VII of the transfer substrate shown in FIG. 6 and 7, the transfer substrate 21 includes a substrate 22, a conductive portion 24 insulated and separated from the substrate 22 via an insulating portion 23, and a lead electrode 25. The conductive portion 24 is composed of a conductive portion 24a having an island pattern shape and a conductive portion 24b present in an island pattern shape around the conductive portion 24a via a separation area 28.
4a and the conductive portion 24b form substantially the same plane. The conductive portion 24a is connected to a conductive layer 26a formed inside the insulating portion 23 via a connecting portion 27a, and the conductive portion 24b is connected to a conductive layer 26b also formed inside the insulating portion 23.
b. One end of the conductive layer 26a is a lead electrode 25a, and one end of the conductive layer 26b is a lead electrode 25b. Therefore, the conductive portions 24a and 24b are connected to the lead electrodes 25a and 25b, respectively, and the conductive portions 24a and 24b
Are electrically independent for each lead electrode 25a, 25b.

FIG. 8 is a plan view showing another example of the transfer substrate of the present invention. In FIG. 8, the transfer substrate 31 is
A substrate 32, a conductive portion 34 insulated and separated from the substrate 32 via an insulating portion 33, and a lead electrode 35 are provided.

The conductive portion 34 includes a conductive portion 34a scattered in three places in the island pattern shape, and a conductive portion 34b existing in the island pattern shape around the conductive portion 34a via the separation area 38. The conductive portion 34a and the conductive portion 34b form substantially the same plane. The conductive portions 34a and 34b are respectively connected to the lead electrodes 35a.
And the lead electrodes 35b, and the conductive portions 34a, 34
b is electrically independent for each lead electrode 35a, 35b.

In each of the above examples, the number of lead electrodes is two.
However, in the transfer substrate of the present invention, the lead electrodes
Any number above can be used. Here, the number of lead electrodes is n (an integer of 2 or more), and the present invention will be described with reference to FIG. 9 as an example of a transfer substrate in which n or more conductive portions are electrically independent for each lead electrode unit. Will be described.

[0031] First, by energizing the predetermined lead electrodes of the transfer substrate 51, electrodepositing desired electrodeposited material E ₁ to a conductive portion connected to the lead electrode (primary electrodeposition 9
(A)). Next, electricity is supplied to another lead electrode, and the desired electrodeposited substance E ₂ is also applied to the conductive portion connected to this lead electrode.
(Secondary electrodeposition, FIG. 9 (B)). Thereafter, the electrodeposition up to the nth order is performed in the same manner, and on the conductive portion of the transfer substrate,
Each electrodeposition of desired electrodeposited material (E ₁ ~E _{n) (n}
Next electrodeposition (FIG. 9 (C)). Thereafter, the transfer substrate 51 and the transfer-receiving body 61 are pressure-bonded via the adhesive 62 (FIG. 9).
(D)), peeling the transfer substrate 51 from the transfer member 61 and the conductive portion Ueno electrodeposited material (collectively E ₁ to E _n) is transferred onto the transferred body 61 (FIG. 9 (E) ).

When the number of electrodeposited substances is less than n,
It is a matter of course that the same electrodeposition substance may be electrodeposited on two or more electrically conductive portions which are simultaneously energized to two or more lead electrodes and are electrically independent from each other.

As described above, according to the transfer pattern forming method of the present invention, different kinds of electrodeposited substances can be transferred onto the same plane by complete self-alignment without the need for processing such as alignment, exposure, and development. Becomes

Next, the present invention will be described in more detail with reference to experimental examples. (Experimental example) Invar material whose surface was sufficiently polished was
After immersion in 30% sulfuric acid to remove the oxide film on the surface of the Invar material, copper plating (2 μm thickness) was applied to one entire surface of the Invar material to form a conductive layer. Next, an insulating rubber-based photoresist (OOH manufactured by Tokyo Ohka Co., Ltd.) is formed on the conductive layer.
MR-85) by a spin coater (coating thickness = 2)
μm), and the photoresist film is contact-exposed and developed using a photomask for forming a through-hole, and then subjected to a bake treatment (150 ° C., 30 minutes) to have a diameter of 100 μm.
An insulating layer having a through hole was formed.

Next, the above conductive layer is used as an electrode, and copper plating (2 μm in thickness) is applied to the entire surface except for one end which will be a lead electrode.
And through-holes were filled with copper plating. Furthermore, after removing the copper surface oxide from the entire surface using 20% hydrochloric acid, the entire surface is immersed in an Enplate Activator 444 and an Enplate PA-492 manufactured by Meltex Co., Ltd. to obtain a catalyst for electroless plating. Granted. And 2
It was immersed in a copper plating solution (Meltex CU-390, manufactured by Meltex Co., Ltd.) at 3 ° C. for 20 minutes to grow electroless copper plating to a thickness of 0.5 μm on the entire surface. Thereafter, the entire surface of the electroless copper plating film was subjected to electrolytic copper plating to form a conductive layer having a thickness of 3 μm.

Next, a photoresist (OFPR-800 manufactured by Tokyo Ohka Co., Ltd.) is applied on the conductive layer, exposed and developed through a photomask for a conductive part, and then is applied to a ferric chloride solution. The exposed conductive layer was etched, and the resist was stripped to form a conductive layer having a predetermined shape (FIG. 3).
(E)).

Thereafter, the insulating layer forming step and the conductive layer forming step as described above are further repeated (see FIG. 4) to form a conductive portion having an island pattern shape as shown in FIG. An electrode-separated transfer substrate having a conductive portion present through a separation area and having two lead electrodes separated from each other was manufactured. The width of the separation area of the transfer substrate was set to 10 μm.

Next, of the lead electrodes of the transfer substrate thus prepared, a lead electrode connected to the conductive portion having the island pattern is energized, and the conductive pattern is formed in the island pattern using a pyrophosphate-based copper plating bath. Only the part was plated with copper. Thereafter, a current was applied to a lead electrode connected to the peripheral conductive portion, and an acrylic resin was electrodeposited. Thus, a conductive metal pattern and an insulating pattern surrounding the conductive metal pattern were formed on the same plane of the transfer substrate.

On the other hand, an acrylic pressure-sensitive adhesive was applied to a thickness of about 2 μm on a glass substrate as a transfer object by spin coating to form a pressure-sensitive adhesive layer. Then, the transfer substrate and the glass substrate are opposed to each other so as to be parallel to each other, and then a pressure of about 5 kgf / cm ² is applied from the transfer substrate side to apply the conductive metal pattern and the insulating pattern to the adhesive layer. Was crimped. Thereafter, when the transfer substrate was peeled off from the glass substrate, the above-described conductive metal pattern and insulating pattern could be collectively transferred onto the glass substrate.

[0040]

As described above in detail, according to the present invention, the conductive portion is electrically divided for each lead electrode without being restricted by the connection between the conductive portion and the lead electrode. A desired electrodeposited substance can be deposited on the conductive portion every time, and these electrodeposited substances are collectively transferred to the transfer target, thereby eliminating the need for processing such as alignment, exposure, and development. It is possible to transfer different kinds of electrodeposited substances on the same plane by alignment. For example, by repeating such a transfer, it becomes possible to produce a multilayer printed wiring board only by the transfer step.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a transfer substrate of the present invention. .

FIG. 2 is a cross-sectional view of the transfer substrate shown in FIG. 1 taken along the line II-II.

FIG. 3 is a view illustrating a method of manufacturing a transfer substrate according to the present invention.

FIG. 4 is a view illustrating a method of manufacturing a transfer substrate according to the present invention.

FIG. 5 is a cross-sectional view showing an electrodeposition pattern that grows on an adjacent conductive part via an isolation area.

FIG. 6 is a plan view showing another example of the transfer substrate of the present invention.

7 is a sectional view of the transfer substrate shown in FIG. 6, taken along line VII-VII.

FIG. 8 is a plan view showing another example of the transfer substrate of the present invention.

FIG. 9 is a view for explaining a transfer pattern forming method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Transfer board 2 ... Substrate 3 ... Insulating part 4 (4a, 4b) ... Conductive part 5 (5a, 5d) ... Lead electrode 6a, 6b ... Conductive layer 7a, 7b ... Connection part

Claims (5)

(57) [Claims] 1. A conductive substrate comprising: a substrate; two or more conductive portions which are insulated and separated on the substrate via an insulating portion and are formed so as to be substantially coplanar; and two or more lead electrodes. Each of the portions has a predetermined pattern and is electrically connected to any of the lead electrodes, and at least one of the conductive portions is electrically connected to the lead electrode via a conductive layer provided in the insulating portion. A transfer substrate, wherein the conductive portion is electrically independent for each lead electrode unit. 2. The semiconductor device according to claim 1, wherein at least one of the conductive portions excluding a conductive portion electrically connected to the lead electrode via the conductive layer also functions as the lead electrode.
The transfer substrate as described in the above. 3. A multi-layer structure in which the same number of the conductive layers as the number of the lead electrodes are provided in the insulating portion while being insulated from each other, and the predetermined conductive layer and the predetermined conductive portion are electrically connected to each other, and the conductive layer 2. The transfer substrate according to claim 1, wherein the end of the transfer substrate is a lead electrode. 4. The method according to claim 1, wherein the insulating portion is formed of any one of a butadiene rubber-based, polyisoprene rubber-based, and polyimide-based insulating organic material, silicon oxide, silicon nitride, and a metal anodic oxide. The transfer substrate according to claim 1, wherein: 5. A transfer substrate according to claim 1, wherein a desired electrodeposition material is deposited on a conductive portion for each lead electrode of the transfer substrate, and thereafter, the electrodeposition is performed. A method for forming a transfer pattern, comprising transferring a substance to an object to be transferred.