JPH03291879A - Method for manufacturing electrical connection members - Google Patents

Abstract

PURPOSE:To stabilize the purity of the surface of a conductive member and to obtain a high connecting strength by removing eutectic layers of a metal to compose a base and a metal to compose the conductive member. CONSTITUTION:A polyimide resin 2 is provided on a copper plate 1, holes 3 are provided, and the copper plate 1 is cut to form recesses 4. In this case, the diameter of each recess 4 is made larger than the bore of the hole 3 and smaller than half the distance to the outer surface of the neighboring hole 3. A gold plating is applied by using the copper plate 1 as the common electrode, to fill the gold 5 in the holes 3 and the recesses 4, and the golds 5 are projected from the surface of the resin 2. In this case, eutectic layers 6 of the gold 5 and the copper are formed at the bottom of the recesses 4. The copper plate 1 is cut and removed selectively, and then the golds 5 are cut and removed partially to remove the eutectic layers 6, so as to form an electric connecting member 31. The projections at the side of no eutectic layer are packed and only the eutectic layer is cut and removed. By connecting plural circuit parts each other by using such a connecting member, the connecting strength in each conductive member 5 is made high, an uneven strength is eliminated, and a highly accurate connection can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing an electrical connection member used for electrically connecting electrical circuit components.

[Conventional technology]

Examples of methods for electrically connecting electrical circuit components include wire bonding and TAB (Tape Out).

The mated boncling method and the like are conventionally known. However, these methods have drawbacks such as being unable to cope with an increase in the number of connection points between both electrical port components and being costly. In order to solve these difficulties, it is possible to electrically connect electrical circuit components to each other using an electrical connection member that has a structure in which a plurality of conductive members are insulated from each other in an insulating holder. It is publicly known (Japanese Patent Application Laid-open No. 1983-
222437 Publication 1, Japanese Unexamined Patent Application Publication No. 63-224235, etc.).

FIG. 2 is a schematic diagram showing electrical connections between electrical circuit components using such electrical connection members. In the figure, 31 is an electrical connection member, and 32 and 33 are electrical circuit components to be connected. show. The electrical connection member 31 includes a plurality of conductive members 34 made of metal or alloy, each of which is electrically insulated from each other, and provided in a holder 35 made of an electrically insulating material. , one end 38 of the conductive member 34 is exposed to one electric circuit component 32 side, and the other end 39 of the conductive member 34 is exposed to the other electric circuit component 33 side (FIG. 2(a)). Then, the connection portion 36 of one electric circuit component 32 and one end 38 of the conductive member 34 exposed on the side of the electric circuit component 32 are joined by alloying, and the connection portion 37 of the other electric circuit component 33 and By alloying the other end 39 of the conductive member 34 exposed on the side of the electric circuit component 33, they are joined, and the electric circuit components 32 and 33 are electrically connected to each other (FIG. 2(b)).

Such an electrical connection member has the following advantages.

(2) By reducing the size of the conductive member, it is possible to miniaturize the connecting parts of electrical circuit components and increase the number of connection points, thereby enabling higher-density connections between electrical circuit components.

■ Even if electrical circuit components have different thicknesses, by changing the thickness of the electrical connection member, it is possible to always keep the height of the electrical circuit components constant, making multilayer connections easier and creating higher-density connections. Implementation is possible.

■ By increasing the protruding height of the conductive member connected to the connection part of the electric circuit component, it is possible to make a stable connection even if the connection part of the electric circuit component is dropped from the surface, and it is possible to avoid complicated connections. Even electrical circuit components having different shapes can be easily connected to each other.

■ Heat generated from electrical circuit components is radiated through the holder of the electrical connection member, so changes in electrical characteristics due to heat are extremely small. Furthermore, since it has excellent heat dissipation characteristics, the effect of thermal fatigue is small and reliability is high. At this time, the holder may be made of an insulating material mixed with a highly thermally conductive metal or ceramic, and the effect will be even greater if a ceramic with a high thermal conductivity is used as the holder.

- Since the length of connection between electrical circuit components is shortened, impedance can be reduced and it is possible to increase the speed of electrical circuit components. By mixing a metal with a low dielectric constant into the holder, it is possible to reduce the parasitic capacitance and further reduce the impedance.

A method of manufacturing the above-mentioned electrical connection member for making electrical multi-point connections between electrical circuit components is disclosed in Japanese Patent Application No. 63-
There is one proposed in No. 133401. Hereinafter, this manufacturing method will be briefly explained based on FIG. 3, which schematically shows the steps.

First, a substrate 51 made of a metal sheet such as a copper plate is prepared (FIG. 3(a)), a photosensitive resin 52 is applied onto the substrate 51 using a spin coater, and prebaking is performed at a temperature of around 100°C (Fig. 3(a)). Figure 3 (g))). After exposing the photosensitive resin 52 to light through a photomask (not shown) having a predetermined pattern, development is performed. The photosensitive resin 52 remains in the exposed portions, and the photosensitive resin 52 is removed in the unexposed portions by development processing to form a plurality of holes 53 (FIG. 3(C)). 200-400
After curing the photosensitive resin 52 by raising the temperature to ℃,
Etching is performed by immersing the base 51 in an etching solution to form a recess 54 in the base 51 that communicates with the hole 53 (
Figure 3(d)).

Next, gold plating is applied using the base 51 as a common electrode,
Hole 53. The recess 54 is filled with gold 55, and gold plating is continued until a bump is formed (FIG. 3(e)). Finally, the base 51 is removed by etching, and the electrical connection member 31 is removed.
(Fig. 3(f)).

In the electrical connection member 31 manufactured in this way, the gold 55 constitutes the conductive member 34 and the photosensitive resin 52 constitutes the holder 35. The dimensions of each part of the electrical connection member 31 are such that the thickness of the photosensitive resin 52 (holding body 35) is approximately 10 μm, and the diameter of the hole 53 (conductive member 34) is approximately 2 μm.
0 μm, the pitch is approximately 40 μm, and the amount of protrusion of the conductive member 34 is approximately several μm on both the front and back sides.

[Problem to be solved by the invention]

However, as mentioned above, the patent application No. 13340/1983
The manufacturing method proposed in No. 1 still has the following problems, and there is room for further improvement.

When forming the conductive member 34 by gold plating, gold nuclei are first generated on the base 51, and the exposed base 51 is covered with gold 55.
The metal (copper) in the base 51 penetrates until it is covered, and pure gold is not deposited in this part, but the gold 55 and the metal (copper) in the base 51 are eutectoid.

FIG. 4 is an enlarged schematic cross-sectional view of the process after gold plating in the conventional manufacturing method, and shows the base 5 exposed in the recess 54.
The metal (fi) in the base 51 is coated with gold 55.
The gold 55 is also precipitated, and a eutectoid layer 56 of the gold 55 and the metal (copper) in the base 51 is formed. The occurrence of such eutectoid 11i56 can be improved to some extent by performing gold strike plating before gold plating, but the eutectoid layer 56 can be completely prevented from occurring due to pinholes or eutectoid formation on the gold strike plating. It is difficult to do so. The base 51 to a certain depth
If the metal (copper) inside enters, the formed eutectoid layer 56 will not be removed even if the base 51 is removed by metal etching in the next step.

As described above, in the conventional manufacturing method, the electrical connection member is manufactured with the eutectoid layer remaining on the protruding portion of the conductive member on the base side. When the electrical connection member manufactured in this manner is bonded to a connection portion of an electric circuit component, there is a problem that variations in bonding strength or bonding defects occur.

The present invention has been made in view of the above circumstances, and provides an electrical connection member that can solve the above-mentioned problems and manufacture electrical connection members with stable characteristics by including a step of removing the eutectoid layer. An object of the present invention is to provide a method for manufacturing a connecting member.

[Means to solve the problem]

A method for manufacturing an electrical connection member according to the present invention includes a holder made of an electrically insulating material, and a plurality of conductive members provided in the holder in an insulated state, each of the conductive members One end is flush with one surface of the holding body or exposed in a shape protruding from this surface, and the other end of each of the conductive members is flush with or protruding from the other surface of the holding body. In the method of manufacturing an electrical connection member exposed at protrude from one or this side,
The method is characterized by comprising the steps of filling the hole with a conductive material that will become the conductive member, removing the base, and etching a part of the filled conductive material on the base side.

(Function) In the method for manufacturing an electrical connection member of the present invention, after filling the conductive material, a part of the conductive material on the base side is etched away. The eutectoid layer with the conductive material is removed, and the purity of the conductive material in the formed conductive member increases.In the electrical connection member manufactured by the present invention, the purity of the conductive member is high, so it can be used as an electric circuit component. When bonded, there is no variation in bonding strength, and highly reliable bonding is achieved.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on drawings showing embodiments thereof.

FIG. 1 is a schematic cross-sectional view showing the manufacturing process of the present invention.

First, an insulator such as a polyimide resin 2 is provided on a copper plate 1 which is a base, and a plurality of holes 3 are formed in the polyimide resin 2 in a predetermined pattern to expose the copper plate 1 below the large holes 3 (first Figure (a)) In this step, a plurality of holes 3 may be formed by photolithography on a photosensitive polyimide resin as in the conventional example, or a plurality of holes 3 may be formed by photolithography and etching on a thermosetting polyimide resin. The holes 3 may be formed, or a plurality of holes 3 may be formed by irradiating the polyimide resin with laser light. In addition, unlike such a process, a plurality of holes 3 are formed in the polyimide resin 2, which is an insulator, by photolithography technology or laser etching, and then the polyimide resin 2 with the holes 3 formed therein is bonded to a copper plate, which is the substrate. It may also be provided on top of 1.

Next, the copper plate 1 that has been treated in this way is immersed in an etching solution to perform etching, and the copper plate 1 near the hole 3 is etched.
A recess 4 communicating with the hole 3 is formed in the copper plate 1 by etching away a portion of the hole 3, and the copper is completely exposed at the bottom of the hole 3 (
Figure 1 (bl). At this time, the diameter of the recess 4 to be formed is
It is assumed that the diameter is larger than the diameter of the hole 3 and smaller than half the distance to the outer periphery of the adjacent hole 3. By controlling the size of the recess 4 in this manner, it is possible to manufacture an electrical connection member in which adjacent conductive members are not electrically connected to each other and in which the conductive members are not removed.

Next, the three-layer hole recess 4 is filled with gold 5 by gold plating using the copper plate 1 as a common electrode, and gold plating is continued until the gold 5 protrudes from the surface of the polyimide resin 2 (see Fig. 1 (C). )). At this time, as in the conventional example, the copper in the copper plate 1 is precipitated until the gold 5 covers the copper plate 1 exposed in the recess 4, and the eutectoid layer 6 of gold 5 and copper forms at the bottom of the recess 4. is formed.

The copper plate 1 is removed by metal etching using an etching solution that etches copper but not gold and polyimide resin (FIG. 1(d)).

At this time, if the eutectoid layer 6 is thicker than a certain level, the eutectoid layer 6 is not removed. Finally, the gold 5 protruding from the polyimide resin 2 is partially etched (less than 1 μm in thickness) by being immersed in an etching solution to remove the eutectoid layer 6 and manufacture the electrical connection member 31. Figure 1(e)). Here, if the protruding part on the side where the eutectoid layer 6 does not exist is backed to prevent the etching solution from entering, it is possible to remove only the eutectoid layer 6 without unnecessarily scraping this part. It is possible.

In the electrical connection member 31 manufactured in this manner, the gold 5 constitutes the conductive member 34 and the polyimide resin 2 constitutes the holder 35. Note that the dimensions of each part of the manufactured electrical connection member 31 are the same as those of the conventional example.

In the embodiment described above, the conductive member 34 was formed by filling gold 5 by plating, but other methods, such as carbon
VD (chemical vapor deposit)
It is also possible to perform selective growth using ion).

Some of the electrical connection members manufactured according to the present invention have a wiring pattern. At that time, the wiring pattern may be present inside the holder, or may be present on one or both surfaces of the holder.

The individual conductive members provided and the wiring pattern may or may not be electrically connected. Further, the electrical connection may be made inside the holder, or may be made on one or both sides of the holder. The material of the wiring pattern is not limited to metal materials, but may be other conductive materials. Note that it is preferable that the end of the connecting portion of the conductive member has a convex shape. Furthermore, the electrical connection member may be composed of one layer or multiple layers of two or more layers.

Further, in this embodiment, gold 5 was used as the material of the conductive member 34, but in addition to gold (^U), Cu, 8g+Be, C
a.

Mg+ Mo, Ni, w, Fe, Tt, In
, Ta, Zn+ AI+ 5nPb-Sn, or other metals or alloys can be used. The conductive member 34 may be made of one kind of metal or alloy, or may be made of a mixture of several kinds of metals and alloys. Alternatively, a metal material containing one or both of an organic material and an inorganic material may be used. Note that the cross-sectional shape of the conductive member 34 can be circular, square, or other shapes, but a shape without corners is desirable in order to avoid excessive concentration of stress. Further, the conductive member 34 does not need to be disposed vertically in the holder 35, and may be obliquely arranged from one surface of the holder 35 to the other surface of the holder 35.

Further, the thickness of the conductive member 34 is not particularly limited. In addition,
The exposed portion of the conductive member 34 may be on the same surface as the holder 35, or may protrude from the surface of the holder 35. just,
In order to stably connect to the connection part of the electric circuit component and ensure the reliability of the connection part, the conductive member 34 connected to the connection part of the electric circuit component should stably protrude from the holder 35. This is desirable.

Further, in this embodiment, polyimide resin 2 is used as the insulating layer serving as the holder 35, but epoxy resin, silicone resin, etc. may be used in addition to this. In addition, powders, fibers, and plate-like materials can be found in such resins.

One or more types of inorganic materials, metal materials, and alloy materials may be dispersed and contained in a desired shape such as a rod-shaped body 1 or a spherical body. Specifically, the metal material 1 alloy material contained is ^u, Ag, Cu+AI.

Be, Ca+ Mg, Mo+ Fe, Ni+ C
o, Mn, W, Cr, Nb.

Zr, Ti, Ta, Zr+, Sn, Pb-5
n, etc., and the contained inorganic materials include 510z
+8203+412031 NazO.

KzO, Cab, ZnO+ Bad, pbo, 5
bz03+ AszOz+ LazO:++Zr0z+
PzOs+ 'real, MgO, SiC,
IN to Bed, BP, BN+.

BaC, TaC, TiBz+ CrB, TiN, 5
iJ4. Ceramic, diamond, glass, carbon such as Tag's.

Examples include boron.

Further, in this example, the copper plate 1 was used as the substrate, but the substrate is not limited to this, and may include Au, Ag, Be, Ca, Mg, M
o, Ni+W.

Fe, Ti, In, Ta+Zn, 8I, Sn
, Pb-5n, or other metal or alloy thin plates can be used. However, since only the base is selectively etched away in the final step, the material of the conductive member 34 and the material used for the base must be different.

〔Effect of the invention〕

Since the manufacturing method of the present invention includes the step of removing the eutectoid layer between the metal constituting the base and the metal constituting the conductive member, it is possible to manufacture an electrical connection member with stable purity on the surface of the conductive member. can.

When electrical circuit components are connected to each other using the electrical connection members manufactured according to the present invention, each conductive member has high bonding strength and there is no variation in bonding strength, achieving high-precision connections. The present invention has excellent effects such as:

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing the steps of the manufacturing method according to the present invention, FIG. 2 is a schematic view showing an example of the use of an electrical connection member, and FIG. 3 is a schematic cross-sectional view showing the steps of the conventional manufacturing method. Figure, 4th
The figure is a schematic cross-sectional view for explaining the problems of the conventional manufacturing method.

Claims (1)

[Claims] 1. It has a holder made of an electrically insulating material, and a plurality of conductive members provided in the holder insulated from each other, and one end of each of the conductive members is flush with or flush with one surface of the holder. A method for manufacturing an electrical connection member that is exposed in a shape that projects from this surface, and the other end of each of the conductive members is flush with the other surface of the holder or exposed in a shape that projects from this surface. the step of producing a base body having on its surface an insulator serving as the holder provided with a plurality of through holes; An electrical connection member comprising: filling a conductive material to become a conductive member; removing the base; and etching a part of the filled conductive material on the base side. Production method.