JPH104262A - Multilayer wiring board - Google Patents

Abstract

(57) Abstract: Separation occurs between an organic resin insulating layer and a thin film wiring conductor. An inner wall of a through hole in which organic resin insulating layers and thin film wiring conductors are alternately laminated on an insulating substrate, and thin film wiring conductors positioned above and below are provided in each organic resin insulating layer. A multi-layer wiring board connected through a through-hole conductor 6 attached to the substrate, wherein at least the surface of the organic resin insulating layer 2 contacting the thin film wiring conductor 3 has a center line average roughness (Ra) of 0. 0.05 μm ≦ Ra ≦ 5 μm, and the count value of the height of irregularities (Pc) at a length of 2.5 mm on the surface is 5 μm when 1 μm ≦ Pc ≦ 10 μm.
00 or more, 2500 μm for 0.1 μm ≦ Pc ≦ 1 μm, and 12,500 or more for 0.01 μm ≦ Pc ≦ 0.1 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer wiring board, and more particularly to a multilayer wiring board used for a hybrid integrated circuit device, a semiconductor element housing package for housing a semiconductor element, and the like.

[0002]

2. Description of the Related Art Conventionally, a multilayer wiring board used for a hybrid integrated circuit device, a package for accommodating a semiconductor element, or the like, has its wiring conductor formed by a thick film forming technique such as the Mo-Mn method.

[0003] This Mo-Mn method is generally used for tungsten,
Organic solvents for high melting point metal powders such as molybdenum and manganese,
A solvent is added and mixed, and a paste-like metal paste is applied by printing on the outer surface of the green ceramic body in a predetermined pattern by a screen printing method. Then, a plurality of these layers are laminated and fired in a reducing atmosphere to obtain a high melting point. This is a method of sintering and integrating a metal powder and a green ceramic body.

Incidentally, the ceramic body on which the wiring conductor is formed is usually an oxide ceramic such as an aluminum oxide sintered body or a mullite sintered body, or an aluminum nitride having an oxide film adhered on the surface. Non-oxide ceramics such as a porous sintered body and a silicon carbide sintered body are used.

However, when the wiring conductor is formed by using the Mo-Mn method, the wiring conductor is formed by screen-printing a metal paste. Had the drawback that it could not be done.

In order to solve the above-mentioned drawbacks, a multi-layer wiring board formed using a thin film forming technique capable of miniaturization instead of forming the wiring conductor by the conventional thick film forming technique is used. It has become.

Such a multilayer wiring board is formed by spin coating an insulating substrate made of a glass epoxy resin or the like formed by impregnating a glass cloth woven with ceramics or glass fibers made of an aluminum oxide sintered body or the like with an epoxy resin. An organic resin insulating layer composed of an epoxy resin formed by a method and a thermosetting treatment, and a metal such as copper and aluminum are formed by employing a thin film forming technique such as an electroless plating method or a vapor deposition method and a photolithography technique. And alternately laminated thin film wiring conductors, and electrically connect the upper and lower thin film wiring conductors through through hole conductors attached to the inner walls of the through holes provided in the organic resin insulating layer. doing.

In this multilayer wiring board, the through holes formed in each organic resin insulating layer employ photolithography technology. Specifically, first, a resist material is applied onto the organic resin insulating layer. Exposure and development are performed on this to form a window of a predetermined shape at a predetermined position, and then an etchant is disposed on the window of the resist material to remove the organic resin insulating layer located on the window of the resist material. Then, a hole (through hole) is formed in the organic resin insulating layer, and finally, the resist material is peeled off from the organic resin insulating layer and removed.

[0009]

However, this multilayer wiring board has poor adhesion between the epoxy resin forming the organic resin insulating layer and the metal such as copper or aluminum forming the thin film wiring conductor, and the organic resin insulating layer Also, when an external force is applied to the thin film wiring conductor, the external force causes a disadvantage that peeling easily occurs between the organic resin insulating layer and the thin film wiring conductor.

[0010]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above-mentioned drawbacks, and has as its object to provide a multilayer wiring board in which an organic resin insulating layer and a thin-film wiring conductor are firmly joined. is there.

According to the present invention, an organic resin insulating layer and a thin film wiring conductor are alternately laminated on an insulating substrate, and thin film wiring conductors positioned above and below are adhered to the inner wall of a through hole provided in each organic resin insulating layer. A multilayer wiring board connected via the through-hole conductors, wherein at least a surface of the organic resin insulating layer in contact with the thin-film wiring conductor has a center line average roughness (Ra) of 0.05 μm ≦ Ra ≦ 5 μm. And the count value of the unevenness height (Pc) at a length of 2.5 mm on the surface is 500 or more for 1 μm ≦ Pc ≦ 10 μm; 2500 or more for 0.1 μm ≦ Pc ≦ 1 μm;
It is characterized in that 12,500 μm ≦ 01 μm ≦ Pc ≦ 0.1 μm.

According to the multilayer wiring board of the present invention, at least the surface of the organic resin insulating layer in contact with the thin film wiring conductor has a center line average roughness (Ra) of 0.05 μm ≦ Ra ≦ 5 μm and a surface of 2.5 mm. The count value of the height (Pc) of the unevenness in the length is 500 when 1 μm ≦ Pc ≦ 10 μm,
0.1 μm ≦ Pc ≦ 1 μm: 2500 or more, 0.01
Since μm ≦ Pc ≦ 0.1 μm is 12,500 or more, the bonding area between the organic resin insulating layer and the thin film wiring conductor is greatly increased, and the adhesion between the two is remarkably improved. Even if an external force is applied, the external force does not cause separation between the organic resin insulating layer and the thin-film wiring conductor, and the bonding between the two can be made extremely strong.

Further, according to the multilayer wiring board of the present invention, since the wiring is formed on the insulating substrate by the thin film forming technique, the wiring can be miniaturized, and the wiring can be formed at an extremely high density.

[0014]

Next, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows an embodiment of a multilayer wiring board according to the present invention, wherein 1 is an insulating substrate, 2 is an organic resin insulating layer, and 3 is a thin film wiring conductor.

On the upper surface of the insulating substrate 1, a multi-layer wiring 4 composed of an organic resin insulating layer 2 and a thin-film wiring conductor 3 is disposed, and functions as a support member for supporting the multi-layer wiring 4.

The insulating substrate 1 is made of an oxide ceramic such as an aluminum oxide sintered body or a mullite sintered body, or an aluminum nitride sintered body having an oxide film on its surface.
It is made of an electrically insulating material such as a non-oxide ceramic such as a silicon carbide sintered body, and a glass epoxy resin in which a cloth woven with glass fibers is impregnated with an epoxy resin. In the case of a compact, a suitable organic solvent and a solvent are added to raw material powders such as alumina, silica, calcia, and magnesia to form a slurry by mixing and adding the same to a conventionally known doctor blade method or calender roll. By forming the ceramic green sheet (ceramic raw sheet) by adopting the method,
Thereafter, the ceramic green sheet is subjected to an appropriate punching process so as to have a predetermined shape and a high temperature (about 16 ° C.).
(00 ° C.) or by mixing a raw material powder such as alumina with an appropriate organic solvent and a solvent to adjust the raw material powder and form the raw material powder into a predetermined shape by a press molding machine. About 1600 ° C
If it is made by firing at a temperature of, and made of glass epoxy resin, for example, impregnating the epoxy resin precursor into a cloth woven of glass fibers and heat curing the epoxy resin precursor at a predetermined temperature Produced by

On the upper surface of the insulating substrate 1, an organic resin insulating layer 2 and thin film wiring conductors 3 are alternately arranged in multiple layers and a multilayer wiring 4 is attached. The resin insulating layer 2 functions to electrically insulate the thin film wiring conductors 3 positioned above and below, and the thin film wiring conductor 3 functions as a transmission path for transmitting an electric signal.

The organic resin insulating layer 2 of the multilayer wiring 4 is made of an epoxy resin. For example, when it is made of an epoxy resin, bisphenol A type epoxy resin, novolak type epoxy resin, glycidyl ester type epoxy resin, etc. A curing agent such as an imidazole-based curing agent or an acid anhydride-based curing agent is added and mixed to obtain a paste-like epoxy resin precursor, and the epoxy resin precursor is applied to the upper portion of the insulating substrate 1 by spin coating. After a while
This is formed by heat-treating with heat of about 80 ° C. to 200 ° C. for 0.5 to 3 hours and heat curing.

A through hole 5 having a minimum diameter of about 1.5 times the thickness of the organic resin insulating layer 2 is formed at a predetermined position in each of the organic resin insulating layers 2 of the multilayer wiring 4. The through-hole 5 functions as a forming hole for forming a through-hole conductor 6 that electrically connects each of the thin film wiring conductors 3 located above and below via an organic resin insulating layer 2 described later.

The through-holes 5 provided in the organic resin insulating layer 2 are formed at predetermined positions by, for example, photolithography, specifically, applying a resist material onto the organic resin insulating layer 2 and exposing and developing the resist material. A window having a predetermined shape is formed, and then an etchant is disposed on the window of the resist material, the organic resin insulating layer 2 located on the window of the resist material is removed, and a hole ( A through hole is formed, and finally, the resist material is peeled off from the organic resin insulating layer 2 and removed.

The organic resin insulating layer 2 has a center line average roughness (Ra) of at least 0.05 μm ≦ Ra ≦ 5 μm, and a surface in contact with at least the thin film wiring conductor 3 described later.
The count value of the height of unevenness (Pc) in the length of mm is 1 μm ≦ Pc ≦ 10 μm.
2500 or more m ≦ Pc ≦ 1 μm, 0.01 μm ≦ P
When c ≦ 0.1 μm is roughened so as to be 12,500 or more, thereby forming the thin film wiring conductor 3 on the organic resin insulating layer 2, the organic resin insulating layer 2 and the thin film wiring conductor 3 The bonding area becomes extremely large. As a result, the adhesion between the organic resin insulating layer 2 and the thin film wiring conductor 3 is remarkably improved, and even when an external force is applied to the organic resin insulating layer 2 and the thin film wiring conductor 3, As a result, no separation occurs between the organic resin insulating layer 2 and the thin film wiring conductor 3, and the bonding between them can be made extremely strong.

When the center line average roughness (Ra) of the surface of the organic resin insulating layer 2 satisfies 0.05 μm> Ra, the adhesion between the organic resin insulating layer 2 and the thin film wiring conductor 3 is reduced,
If Ra> 5 μm, fine processing of the thin film wiring conductor 3 formed on the upper surface becomes impossible. Therefore, the organic resin insulating layer 2 has a center line average roughness (Ra) of 0.05 on its surface.
It is specified in the range of μm ≦ Ra ≦ 5 μm.

The count value of the height (Pc) of the unevenness at a length of 2.5 mm on the surface of the organic resin insulating layer 2 is less than 500 when 1 μm ≦ Pc ≦ 10 μm.
1 μm ≦ Pc ≦ 1 μm less than 2500, 0.01 μm
If ≦ Pc ≦ 0.1 μm is less than 12,500, the adhesion between the organic resin insulating layer 2 and the thin-film wiring conductor 3 is reduced. Therefore, the organic resin insulating layer 2 has a thickness of 2.5
The count value of the height of unevenness (Pc) in the length of mm is 1 μm ≦ Pc ≦ 10 μm.
2500 or more m ≦ Pc ≦ 1 μm, 0.01 μm ≦ P
c ≦ 0.1 μm is specified in a range of 12,500 or more.

The count value of the center line average roughness (Ra) of the surface of the organic resin insulating layer 2 and the height of the unevenness (Pc) at a length of 2.5 mm of the surface are calculated as follows.
Is scanned at a diagonal of 50 μm square (70 μm) with an atomic force microscope (Dimension 3000-Nano Scope III manufactured by Digital Instruments Inc.) to inspect and measure the surface state.
Each numerical value was obtained from the measurement result.

The center line average roughness (Ra) of the surface is 0.05 μm ≦ Ra ≦ 5 μm, and the count value of the unevenness height (Pc) at a length of 2.5 mm of the surface is 1 μm ≦
500 or more Pc ≦ 10 μm, 0.1 μm ≦ Pc ≦ 1
2500 μm or more, 0.01 μm ≦ Pc ≦ 0.1 μ
The surface of the organic resin insulating layer 2 having a m of 12,500 or more is subjected to a reactive ion etching treatment by blowing a gas such as CHF ₃ , CF ₄ , Ar, etc. onto the upper surface of the organic resin insulating layer 2 so that the surface has a predetermined roughness Roughened.

A thin film wiring conductor 3 having a predetermined pattern is provided on the upper surface of each organic resin insulating layer 2, and a through hole conductor 6 is provided on an inner wall of a through hole 5 provided in each organic resin insulating layer 2. Each of the thin-film wiring conductors 3 located above and below the organic resin insulating layer 2 with the through-hole conductor 6 interposed therebetween is electrically connected.

The thin-film wiring conductor 3 and the through-hole conductor 6 provided on the upper surface of each of the organic resin insulating layers 2 and in the through-holes 5 are made of a metal material such as copper, nickel, gold, or aluminum by electroless plating or vapor deposition. For example, in the case of being formed of copper, copper sulfate is formed on the upper surface of the organic resin insulating layer 2 and the inner surface of the through-hole 5 when the film is formed of copper. 0.06 mol / liter, formalin 0.3 mol /
Liter, sodium hydroxide 0.35 mol / l,
A copper layer having a thickness of 1 μm to 40 μm is applied using an electroless copper plating bath composed of 0.35 mol / liter of ethylenediaminetetraacetic acid, and thereafter, the copper layer is processed into a predetermined pattern by an etching method. Through holes 5 between each organic resin insulating layer 2 and each organic resin insulating layer 2
It is arranged on the inner wall. In this case, since the thin-film wiring conductor 3 is formed by a thin-film forming technique, the wiring can be miniaturized, whereby the thin-film wiring conductor 3 can be formed at an extremely high density.

Incidentally, the multilayer wiring 4 formed by alternately arranging the organic resin insulating layers 2 and the thin film wiring conductors 3 in a multi-layer structure has a thickness of 100 μm or more. When the through-hole 5 is formed by adopting the photolithography technique in 2, the etching processing time becomes long, making it difficult to form the through-hole 5 into a desired clear shape. When roughening is performed on the upper surface of the insulating layer 2 to increase the bonding strength of the upper and lower organic resin insulating layers 2, unnecessary holes are formed in the organic resin insulating layer 2 and the upper and lower thin film wiring conductors 3 are formed. There is a risk of causing an unnecessary electrical short. Therefore, it is preferable that the thickness of each of the organic resin insulating layers 2 is in the range of 5 μm to 100 μm. When the thickness of each thin-film wiring conductor 2 of the multilayer wiring 4 is less than 1 μm, the electrical resistance of each thin-film wiring conductor 3 becomes large, and it is difficult to transmit a predetermined electric signal to each thin-film wiring conductor 3. When the thickness exceeds 40 μm, when the thin film wiring conductor 3 is adhered to the organic resin insulating layer 2, a large stress is present inside the thin film wiring conductor 3, and the thin film wiring conductor 3 is formed by the organic resin insulating layer 2 due to the intrinsic stress. It is easier to peel off. Therefore, it is preferable that the thickness of each thin-film wiring conductor 2 of the multilayer wiring 4 be in the range of 1 μm to 40 μm.

Thus, according to the multilayer wiring board of the present invention,
When an electrode such as a semiconductor element and an external electric circuit are connected to the thin film wiring conductor 3 of the multilayer wiring 4, the electrode of the semiconductor element and the like is electrically connected to the external electric circuit via the thin film wiring conductor 3. When an electric signal is transmitted and supplied from an external electric circuit to the semiconductor element via the wiring conductor 3, the semiconductor element performs predetermined driving.

The present invention is not limited to the above-described embodiment, and various changes can be made without departing from the gist of the present invention.

[0031]

According to the multilayer wiring board of the present invention, at least the surface of the organic resin insulating layer in contact with the thin film wiring conductor has a center line average roughness (Ra) of 0.05 μm ≦ Ra ≦ 5 μm,
The count value of the height of unevenness (Pc) at a length of 2.5 mm on the surface is 500 or more for 1 μm ≦ Pc ≦ 10 μm, 2500 or more for 0.1 μm ≦ Pc ≦ 1 μm, and 0.
Since the area of 01 μm ≦ Pc ≦ 0.1 μm is 12,500 or more, the bonding area between the organic resin insulating layer and the thin film wiring conductor is greatly increased, and the adhesion between the two is significantly improved. Even if an external force is applied, the external force does not cause separation between the organic resin insulating layer and the thin-film wiring conductor, and the bonding between the two can be made extremely strong.

Further, according to the multilayer wiring board of the present invention, since the wiring is formed on the insulating substrate by the thin film forming technique, the wiring can be miniaturized, and the wiring can be formed at an extremely high density.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a multilayer wiring board of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Insulating board 2 ... Organic resin insulating layer 3 ... Thin film wiring conductor 4 ... Multilayer wiring 5 ... Through-hole 6 ... Through-hole conductor

Claims (1)

[Claims] An organic resin insulating layer and a thin film wiring conductor are alternately laminated on an insulating substrate, and thin film wiring conductors positioned above and below are adhered to the inner wall of a through hole provided in each organic resin insulating layer. A multilayer wiring board connected through a through-hole conductor, wherein at least a surface of the organic resin insulating layer in contact with the thin-film wiring conductor has a center line average roughness (Ra)
Is 0.05 μm ≦ Ra ≦ 5 μm, and 2.
The count value of the height of unevenness (Pc) in a length of 5 mm is 1 μm ≦ Pc ≦ 10 μm, 500 or more, 0.1 μm
2500 or more m ≦ Pc ≦ 1 μm, 0.01 μm ≦ P
A multilayer wiring board, wherein c ≦ 0.1 μm is 12,500 or more.