JPH06302951A - Wiring board and its manufacture - Google Patents

Abstract

PURPOSE:To easily obtain a wiring board having a composite function by improving the adhesive property between a wiring pattern and substrate so as to eliminate the need of heating operation for improving the adhesion between the pattern and substrate. CONSTITUTION:At the time of forming a wiring pattern on a substrate 10 with an adhesive layer and barrier layer in between, a conductor pattern 12 is formed by etching a conductor layer and tantalum nitride layer 14 after successively forming the layer 14 and the conductor layer on the substrate 10 and, at the same time, resistors 18 are formed in a circuit by utilizing unetched parts of the layer 14 as resistor sections 18b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiring board having a ceramic substrate or an electrically insulating layer such as polyimide as a base material and a method for manufacturing the wiring board.

[0002]

2. Description of the Related Art In a wiring board in which a conductor pattern is provided on a ceramic substrate, an adhesion layer is provided on the ceramic substrate to improve the adhesion between the underlying ceramic substrate and the wiring layer, and the adhesion layer and the wiring layer are also provided. And a barrier layer is provided between and. FIG. 3 shows a configuration example of an adhesion layer, a barrier layer, and a wiring layer provided on the ceramic wiring board. In this example, a titanium layer as the adhesion layer 3 is provided on the ceramic substrate 2, a molybdenum layer as the barrier layer 4 is further provided, and a nickel layer as the wiring layer 5 is provided thereon.

Instead of the above titanium, chromium, tantalum, tungsten, titanium-tungsten alloy, etc. can be used for the adhesion layer 3, and platinum is used for the barrier layer 4.
Cobalt, niobium, etc. can be used. Further, copper or the like can be used as the wiring layer 5. The wiring layer 5 is often plated with gold as a protective layer.

FIG. 4 shows an example of a wiring board in which a wiring pattern is provided in multiple layers using the polyimide layer 7 as an electrically insulating layer. In this case, since the adhesion between the copper layer 8 of the wiring layer and the polyimide layer 7 is low, the chrome layers 9 are provided on both sides of the copper layer 8, and the chrome layer 9 is used as the adhesion layer and the barrier layer, and the copper layer 8 is directly attached. It is formed so as not to contact the polyimide layer 7.

[0005]

However, in the wiring board using the above-mentioned ceramic substrate, in order to improve the adhesion between the wiring layer 5 and the underlying ceramic substrate 2, the adhesion layer 3 and the barrier layer are provided on the ceramic substrate 2. 4. After providing the wiring layer 5,
The entire substrate must be heated to about 900 ° C. for thermal diffusion, which causes a problem of complicated manufacturing process. In addition, when the wiring pattern is formed in multiple layers by using the polyimide layer 7, a heating operation for improving the adhesion between the wiring layer and the adhesion layer is unnecessary, but for example, a resistor is formed in the circuit. However, there is a problem that the operation becomes complicated when the wiring board is to be provided with a composite function.

The present invention has been made in view of these problems, and an object thereof is to reliably and easily form a wiring layer on a ceramic wiring board or the above-mentioned multilayer wiring board. The present invention aims to provide a wiring board that can be manufactured and has excellent functionality, and a manufacturing method thereof.

[0007]

The present invention has the following constitution in order to achieve the above object. That is, in a wiring board in which a wiring pattern is provided on a ceramic substrate or a base material of a polyimide layer via an adhesion layer and a barrier layer, a single tantalum nitride layer is provided as the adhesion layer and the barrier layer. . In the wiring board,
A tantalum oxide layer is provided instead of the tantalum nitride layer. In the wiring board, a nickel-chromium alloy layer is provided instead of the tantalum nitride layer. In addition, in a method for manufacturing a wiring board in which a wiring pattern is provided on a substrate of a ceramic substrate or a polyimide layer via an adhesion layer and a barrier layer, tantalum nitride or a nickel-chromium alloy is used as the adhesion layer and the barrier layer on the substrate. To provide a single-layer adhesion barrier layer, and to form a wiring pattern on the adhesion barrier layer, using the adhesion barrier layer as a resistor portion,
The feature is that a resistor is built in the circuit.

[0008]

[Function] By providing the tantalum nitride layer, the tantalum oxide layer, and the nickel-chromium alloy layer as the adhesion layer and the barrier layer of the wiring pattern, the adhesion between the wiring pattern and the base material is improved, and the base material is heated to a high temperature. The required adhesion can be obtained without doing so, and the manufacturing process can be simplified.
Further, by using a resistor such as tantalum nitride as an adhesion layer or a barrier layer which is an underlayer of the wiring pattern,
The resistor can be easily formed when forming the wiring pattern, and the wiring board having a composite function can be easily manufactured.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows an example in which a wiring pattern 12 made of nickel is formed on a ceramic substrate 10 as an example of the wiring substrate according to the present invention. In the ceramic wiring board of this embodiment, when the wiring pattern 12 is formed on the ceramic substrate 10, the tantalum nitride layer 14 is provided between the wiring pattern 12 and the ceramic substrate 10 as an adhesion layer of the wiring pattern 12 and a barrier layer. It is characterized by

The tantalum nitride layer 14 is a single layer which can improve the adhesion between the ceramic substrate 10 and the wiring pattern 12 and also functions as a barrier layer. In contrast, it is not necessary to heat the entire substrate to improve the adhesiveness, and it is possible to obtain the same adhesiveness as in the case of the conventional adhesive layer by a simple film forming method.

That is, when the ceramic wiring board of the embodiment is formed, a tantalum nitride layer is provided on the ceramic substrate 10 by a sputtering method, the tantalum nitride layer is etched to form a predetermined pattern, and then nickel is sputtered. A nickel layer is provided by etching, and the nickel layer is etched to form a predetermined conductor pattern 12.
In FIG. 1, reference numeral 16 is a via connecting the wiring patterns between the layers. The via 16 is formed by, for example, tungsten metallization.

Since tantalum nitride is a resistor,
When the wiring pattern 12 is formed as described above, a resistor can be built in the wiring layer at the same time. In FIG. 1, reference numeral 18 denotes a resistor formed by using the tantalum nitride layer 14. Reference numerals 18a and 18a are electrodes of resistors, which can be formed simultaneously when the wiring pattern 12 is formed from the nickel layer. Reference numeral 18b is a resistor portion formed by the tantalum nitride layer 14. It is possible to set an appropriate resistance value depending on the film thickness of the tantalum nitride layer 14 and the length of the resistor portion 18b.

By using the tantalum nitride layer 14 in this manner, the wiring pattern 12 can be formed in close contact with the ceramic substrate 10 and a resistor as a circuit component can be easily formed. Although tantalum nitride was used as the adhesion layer and the barrier layer in the examples, tantalum oxide or a nickel-chromium alloy may be used instead. Also in these cases, the required adhesion between the ceramic substrate and the wiring pattern can be obtained without heating to a high temperature as in the embodiment. When a nickel-chromium alloy is used, it can be used as a resistor like tantalum nitride.

FIG. 2 shows an embodiment of a multilayer wiring board in which a wiring pattern is formed between layers using the polyimide layer 20 as an electrically insulating layer. Although a copper layer is used as the wiring pattern 12 in this embodiment, the polyimide layer 20 and the wiring pattern 1 are used.
The tantalum nitride layer 14 is used as a barrier layer between the wiring pattern 12 and the polyimide layer 20 in the same manner as in the above-described embodiment while improving the adhesiveness with the wiring pattern 12. The tantalum nitride layer 14 effectively acts as an adhesion layer and a barrier layer between the polyimide layer 20 and the wiring pattern 12, like the chromium layer 9 in the conventional example shown in FIG.

FIG. 2 shows an example in which a resistor 18 made of a tantalum nitride layer 14 is provided as an intermediate layer when the wiring patterns 12 are formed in multiple layers. The method of forming the resistor 18 is the same as in the above-described embodiment, 18a is an electrode of the resistor 18 made of a copper layer,
18b is a resistor portion made of tantalum nitride. Electrode 18
The tantalum nitride layer 14 is provided on the upper layer of a so that the polyimide layer 20 and the wiring pattern 12 do not come into direct contact with each other.
With the wiring pattern 12, the polyimide layer 20 and the wiring pattern 12 are prevented from directly contacting each other.

Even when a multilayer wiring pattern is provided by using the polyimide layer 20 of this embodiment as an electrical insulating layer, the tantalum nitride layer 14 effectively functions as an adhesion layer and a barrier layer of the wiring pattern 12 as in the above embodiment. Can be provided as a suitable multilayer wiring board. Further, it is possible to easily form a resistor in a circuit by utilizing the tantalum nitride layer 14, and it can be effectively used as a method for manufacturing a multilayer wiring board having a composite function. Also in this embodiment, nickel-chromium alloy may be used instead of tantalum nitride.

[0017]

As described above, according to the wiring board and the method for manufacturing the same of the present invention, the adhesion between the wiring pattern and the base material becomes good, and the operation of heating at a high temperature to improve the adhesion is performed. Is unnecessary, and the manufacturing of the wiring board can be facilitated. In addition, a wiring pattern can be formed on the wiring board, and a resistor can be built in the circuit, so that a wiring board having a composite function can be easily obtained.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of an embodiment of a wiring board.

FIG. 2 is an explanatory diagram showing a configuration of an example of a multilayer wiring board.

FIG. 3 is an explanatory diagram showing a configuration of a conventional example in which a wiring layer is provided on a ceramic substrate.

FIG. 4 is an explanatory diagram of a wiring board in which a polyimide layer is formed in multiple layers as an electrically insulating layer.

[Explanation of symbols]

 2, 10 Ceramic substrate 3 Adhesion layer 4 Barrier layer 5 Wiring layer 7, 20 Polyimide layer 8 Copper layer 9 Chrome layer 12 Wiring pattern layer 14 Tantalum nitride layer 16 Via 18 Resistor 18a Electrode 18b Resistor part

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location H05K 3/46 Q 6921-4E 8719-4M H01L 23/12 B

Claims (4)

[Claims] 1. A wiring board in which a wiring pattern is provided on a ceramic substrate or a base material of a polyimide layer via an adhesion layer and a barrier layer, wherein a single tantalum nitride layer is provided as the adhesion layer and the barrier layer. Characteristic wiring board. 2. The wiring board according to claim 1, wherein a tantalum oxide layer is provided instead of the tantalum nitride layer. 3. The wiring board according to claim 1, wherein a nickel-chromium alloy layer is provided instead of the tantalum nitride layer. 4. A method for manufacturing a wiring substrate, wherein a wiring pattern is provided on a ceramic substrate or a base material of a polyimide layer via an adhesion layer and a barrier layer, wherein tantalum nitride or nickel-containing nickel is used as the adhesion layer and the barrier layer on the base material. A single adhesion barrier layer is provided by depositing a chromium-based alloy, a wiring pattern is formed on the adhesion barrier layer, and the adhesion barrier layer is used as a resistor section to form a resistor in a circuit. A method for manufacturing a wiring board, comprising: