JPH06308158A - Continuity tester - Google Patents

Abstract

PURPOSE:To remove an oxide generated on an aluminum electrode of an IC and an insulation layer caused by adhesion or transcription, and secure the continuity between the aluminum electrode and a bump so as to improve the reliability of a continuity test. CONSTITUTION:A conductive circuit 1 for testing the continuity of an object to be tested is buried in an insulator layer 2 having a flexibility in a manner that it will not be exposed on the surfaces 21 and 22 of the layer 2, and continuity routes 41 and 42, which respectively extend from the surfaces 11 and 12 of the circuit 1 to the surfaces 21 and 22 of the layer 2, are formed as being paired while they are displaced each other in a surfacial direction of the circuit. The routes 41 and 42 are respectively connected with the bumps 51 and 52 which are projected outwardly on the surfaces 21 and 22 of the layer 2, and the circuit l is electrically connected with respective bumps 51 and 52 through respective routes 41 and 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuity inspection device,
More specifically, the present invention relates to a continuity inspection device such as a probe provided at the tip of a tester for conducting continuity inspection of a wiring pattern of a semiconductor substrate.

[0002]

2. Description of the Related Art In recent years, the development of semiconductor substrate manufacturing technology has been remarkable, and the fine patterning of IC wiring has been advanced accordingly, and the number of semiconductor products mounting such fine pattern ICs is increasing year by year. Usually, a tester having a probe as a semiconductor continuity inspection device is used for the continuity inspection of such semiconductor products. A mechanical probe 80 shown in FIG. 9 is exemplified as a conventional probe. The mechanical probe 80 has a main body 83.
Is fixed to the front end wall 84 of the tester, and a needle-shaped contact needle 85 that comes into contact with an electrode of a semiconductor product or the like is attached to the main body 83 so as to be expandable and contractible. However, with this mechanical probe 80, there is a limit to the continuity inspection of semiconductor products that are highly integrated and highly integrated.

On the other hand, this needle type mechanical probe 80
There is a membrane type probe 90 as an improvement of the above, which is configured as shown in FIG. 10, for example. In FIG. 10, a through hole 92 is bored in the insulating layer 91 in the thickness direction, and a conductive path 93 is formed by filling the through hole 92 with a metal substance. Further, on one surface 91a of the insulating layer 91, a conductive layer 1 connected to a conductive circuit for conducting a continuity test of a semiconductor product is formed and electrically connected to the conductive path 93. Further, rivet-shaped bumps 95 that are electrically connected to the conductive paths 93 are formed on the other surface 91b of the insulating layer 91, and the membrane type probe 90 is configured. This membrane type probe 90
Bumps 95 of the aluminum electrodes 97 of the IC 96, for example.
Alternatively, the continuity test is performed by contacting the wiring pattern.

[0004]

However, as shown in FIG.
As shown in FIG. 4, the surface of the bump 95 at the tip of the conventional membrane type probe 90 is formed into a curved surface. Therefore, the presence of the oxide substance layer 98 covering the aluminum electrode 97 of the IC 96 causes the aluminum electrode There is a problem in that conduction cannot be achieved only by making contact with 97. In addition, in the wiring pattern of IC96, adhesion,
If an insulating layer formed by transfer or the like is interposed, even if the bumps 95 are brought into contact with each other, there is a problem in that conduction is poor.
Therefore, the reliability of the continuity test was low in the conventional membrane type probe 90.

The present invention has been made in view of the above conventional problems, and an object thereof is to provide a continuity inspection apparatus having a high reliability of continuity inspection.

[0006]

In a continuity inspection apparatus according to the present invention, a conductive circuit for conducting a continuity inspection of an object to be inspected is embedded in a flexible insulating layer, and is displaced in the plane direction of the conductive circuit. The pair of conductive paths extend in opposite directions from the surface of the conductive circuit, and the contact portions that come into contact with the circuit of the device under test are connected to the conductive paths, respectively.

In particular, the contact portions are formed so as to project outward from the surface of the insulating layer. Further, the contact portion is a protrusion made of a bump-shaped hard metal.

In the present invention, "inspection object" means a semiconductor element, a semiconductor element assembly (a silicon wafer before dicing, a silicon chip after dicing, etc.), a semiconductor device, a circuit board for mounting a semiconductor device, a circuit board for LCD. The “circuit” is a broad concept including not only a wiring pattern but also electrodes, leads and the like. "Connecting" means that they are in electrical contact with each other. "Contact point" refers to a conductor that conducts when it is connected to the circuit of the device under test, and its shape is not particularly limited, and it may be a triangle, a square, a rectangle, a trapezoid, a parallelogram, another polygon, or a circle. Etc., or a solid such as a prism, a cylinder, a sphere, a cone (a cone or a pyramid), and does not necessarily have to be formed so as to project outward from the surface of the insulator layer. It can be arbitrarily set according to the layout of the device under test, the shape of the circuit, and the like.

[0009]

According to the continuity inspection apparatus of the present invention, a pair of inspected objects are displaced in a direction in which they approach each other with the continuity inspected apparatus interposed therebetween, so that, for example, an IC which is a circuit of the inspected object. Of the aluminum electrodes contact the contact portions, and the load acts on the conductive circuit through the conductive paths connected to the contact portions. Since the loads act in the directions opposite to each other by shifting in the plane direction of the conductive circuit, the conductive circuit is distorted in the load direction together with the insulator layer, and the loads act on the contact portions in opposite directions. . The contact portion slides in opposite directions in contact with the aluminum electrode, and the frictional force scrapes off the oxide formed on the aluminum electrode and the insulating layer formed by adhesion, transfer, or the like. Conduction between the electrode and the contact portion is ensured.

In particular, when the contact portions are formed so as to project outward from the surface of the insulating layer,
Even if the circuit of the device under test is flat, the contact with the contact portion is ensured. Further, when the contact portion is a protrusion made of a bump-like hard metal, the oxide and insulating layer formed on the aluminum electrode can be easily removed.

[0011]

EXAMPLES Examples will be given below to explain the present invention in detail, but the present invention is not limited to these examples.

FIG. 1 is a sectional view showing an embodiment of the continuity inspection apparatus of the present invention. Continuity test device T1 shown in FIG.
In the conductive circuit 1 for conducting the continuity inspection of the object to be inspected, the surface 21 of the insulating layer 2 is provided in the flexible insulating layer 2.
It is embedded so as not to be exposed from the surface 22, and the surfaces 11, 12 of the conductive circuit 1 to the surfaces 21, 22 of the insulator layer 2 are buried.
Conductive paths 41 and 42 respectively extending up to are formed in pairs so as to be displaced in the surface direction of the conductive circuit 1. The conductive paths 41, 42 are bump-shaped metal protrusions (hereinafter simply referred to as “bumps”) 5 which are contact portions formed so as to protrude outward from the surfaces 21, 22 of the insulator layer 1.
1 and 52, and the conductive circuit 1 and the bumps 51 and 52 are electrically connected to each other via the conductive paths 41 and 42. In the present invention, the contact portion does not bulge like a bump in this way, and the conductive paths 41 and 42 are formed on the same plane as the surfaces 21 and 22 of the insulator layer 1, and the ends thereof become the contact portion. It goes without saying that the embodiments are also included.

The material for forming the conductive circuit 1 is not particularly limited as long as it is a conductive material such as metal. The thickness of the conductive circuit 1 is not particularly limited, but is preferably set to 1 to 200 μm, preferably 5 to 80 μm.

The material for forming the insulating layer 2 is not particularly limited as long as it stably supports the conductive circuit 1 and the bumps 51 and 52 and has an electric insulating property. Specifically, polyester resin, epoxy resin, urethane resin, polystyrene resin, polyethylene resin, polyamide resin, polyimide resin, acrylonitrile-
A thermosetting resin or a thermoplastic resin such as a butadiene-styrene (ABS) copolymer resin, a polycarbonate resin, a silicone resin, or a fluorine resin can be mentioned. Among them, a polyimide resin excellent in heat resistance and mechanical strength. Resins are particularly preferably used.

The thickness of the insulator layer 2 is not particularly limited, but in order to have sufficient mechanical strength and flexibility, it is preferable to set it to 2 to 500 μm, preferably 10 to 150 μm.

The conductive paths 41, 42 and the bumps 51,
The forming material forming 52 is not particularly limited as long as it has conductivity, and known metal materials can be used. For example, gold, silver, copper, platinum, lead, tin, nickel, cobalt, indium, Rhodium, chrome, tungsten,
Examples include single metals such as ruthenium, and various alloys containing these, such as solder, nickel-tin, and gold-cobalt. Usually, a metal that is hard and resistant to oxidation and has a low electric resistance, such as rhodium, so that the oxide layer on the aluminum electrode that is the circuit of the device under test or the insulating layer on the wiring pattern can be destroyed. Noble metals such as aluminum, ruthenium and platinum are preferably used.

The material forming the conductive paths 41, 42 may be the same substance as or different from the material forming the bumps 51, 52, but usually the same substance is used. In this case, it is preferable that the conductive paths 41 and 42 and the bumps 51 and 52 are integrally formed. Further, as shown in FIG. 2, a structure using three kinds of forming materials may be used. That is, an inexpensive metal substance such as copper is used for the conductive path portion 41a contacting the conductive circuit 1, and gold or the like having high connection reliability is used for the surface layer 41c of the bump 51 contacting the aluminum electrode. Then, the intermediate layer 4 interposed between the central portion 41a and the surface layer 41c.
For 1b, nickel or the like is used as a barrier metal substance for preventing mutual reaction of metal substances. Further, the structure is not limited to the above-mentioned three kinds of forming materials, and may be formed into a structure using four or more kinds of forming materials.

The height of the bumps 51, 52 is not particularly limited, but is preferably several microns to several tens of microns. The bumps 51 and 52 are formed in a hemispherical shape in addition to the mushroom shape (umbrella shape) as shown in FIG. The bumps 51 and 52 may have a triangular shape, a quadrangular shape, or a circular shape. When the bottom shape is circular, the entire shape formed may be a hemisphere or a cylinder.

The bumps 51, 52 may have a shape as shown in FIGS. 3 and 4. In such a shape, the metal protrusions 53, 54 are formed of separate single metals. Alternatively, an alloy may be used. Usually, as a material for forming the metal protrusion 54, inexpensive nickel or copper having excellent conductivity is preferably used. Moreover, as a material for forming the metal protrusions 13,
For example, a metal that is hard and difficult to oxidize and has a low electric resistance, such as rhodium, so that an oxide layer on an aluminum electrode or an insulating layer on a wiring pattern can be destroyed.
Noble metals such as ruthenium and platinum are preferably used.

Further, if a mutual reaction occurs between the two metal projections 53 and 54, each changes the physical properties of the metal, which is not preferable. Therefore, it is preferable to apply a barrier metal between the metal protrusions 53 and 54 in order to maintain the noble physical properties of both metal protrusions 53 and 54. For example, when diffusion occurs like a combination of gold and copper, it is preferable to apply nickel as a barrier metal between gold and copper. When both metal protrusions 53 and 54 are formed by plating using a single metal, the plating condition that the metal becomes brittle due to hydrogen embrittlement and sulfur embrittlement is not preferable. For example, nickel metal formed by using a nickel sulfamate plating solution or using a sulfur-containing additive such as saccharin or naphthalene sodium sulfonate as a brightener for the nickel plating solution is a pure metal nickel. It is a eutectic of an intermetallic compound of Ni ₃ S ₂ and Ni, but when heated by post-treatment,
This intermetallic compound of Ni ₃ S ₂ gathers and becomes brittle.

By forming the minute metal protrusions 53 on the surface of the metal protrusions 54 in this way, it becomes easy to destroy, for example, the oxide layer on the aluminum electrode or the insulating layer on the wiring pattern. Since there are a plurality of contact points between the electrodes and the bumps 51, a reliable conduction test can be performed.

FIG. 5 is a sectional view showing another embodiment of the continuity inspection apparatus of the present invention. In the present embodiment, the reference numerals in FIG. 1 indicate the same or corresponding portions. What should be noted in the continuity test apparatus T2 shown in FIG. 5 is that the conductive circuit has a multilayer structure. That is, in the insulator layer 2, the conductive circuits 12 and 13 connected via the conductive path 43 are embedded, and each conductive circuit 1
Surface 1 on the side where the conducting paths 43 of 2 and 13 are not connected
Conductive paths 41 and 42 are formed to extend from 5 and 16 to the surfaces 21 and 22 of the insulator layer 2, respectively. By thus forming the conductive circuit in a multi-layer structure, the degree of freedom in the wiring design of the device under test is increased more than that in the case where the conductive circuit has a single layer.

The continuity inspection apparatus of the present invention, in addition to the above-mentioned continuity inspection of semiconductor elements, etc., conducts inspection of anisotropic conductors for mounting semiconductor elements, liquid crystal display elements, etc., printed wiring boards, flexible boards. , Or hybrid I
It can also be used for connection or inspection between fine pitch circuits such as C.

FIG. 6 is a sectional view showing a manufacturing process of the continuity inspection apparatus according to the present invention, which can be manufactured, for example, as follows.

First, as shown in FIG. 6A, a conductive circuit 1 such as a copper circuit is formed on one surface of the insulating layer 2a by a known method. Examples of the method of forming the conductive circuit 1 on the surface of the insulator layer 2a include a plating method, a sputtering method, a CVD method and the like. After that, as shown in FIG. 6B, the insulating layer 2 in the region where the conductive path is to be formed is formed.
A hole 32 reaching the surface 12 of the conductive circuit 1 at a is formed only in the insulator layer 2 a so that the conductive circuit 1 is exposed at the bottom of the hole 32. The holes 32 are formed by a mechanical punching method such as punching, plasma processing, laser processing, photolithography processing, or the insulating layer 2.
And chemical etching using resists with different chemical resistance, and laser processing that enables fine processing to cope with fine pitches can be performed by methods such as excimer with controlled pulse number or energy amount. Drilling by laser irradiation is preferable. For example, KrF excimer laser light having an oscillation wavelength of 248 nm is irradiated through a mask to perform dry etching. Hole 32
Has a size of 5 to 200 μm, preferably 8 to 10 μm
The degree.

Next, as shown in FIG. 6C, an insulating layer 2b is laminated by thermocompression bonding, extrusion molding, casting coating, etc. so as to cover the exposed surface 13 of the conductive circuit 1. Then, the conduction circuit 1 is embedded. After that, FIG.
As shown in (D), in the insulator layer 2b, the hole portion 3 reaching the surface 13 of the conductive circuit 1 in the same manner as described above.
1 is formed.

Finally, the holes 31 and 32 are filled with a conductive material to form the conductive paths 41 and 42 and the bumps 51 and 52 to obtain the continuity inspection apparatus according to the present invention.

Conducting paths 41, 42 and bumps 51, 52
Is formed by physically embedding a conductive material in the holes 31 and 32, a CVD method, a plating method such as electrolytic plating or electroless plating, and a structure obtained by the above-mentioned steps, and a molten bath of the conductive material. It can be performed by a chemical method such as immersing in a substrate and pulling it up to deposit a conductive substance.
The method by electrolytic plating using the electrode as an electrode is preferable because it is a simple method. Therefore, in the present invention, the filling of the conductive substance is a broad concept including not only the physical filling of the conductive substance but also the above-mentioned chemical deposition.

The holes 31 and 32 are formed by the insulating layers 2a and 2a.
The holes 31 may be formed after laminating b, or the holes 31 may be formed after the conductive material is filled with the conductive material after forming the holes 32.

The bumps 51 as shown in FIGS. 3 and 4,
In order to form 52, for example, the following method can be adopted.

First, after forming the metal protrusion 54, before forming the metal protrusion 53, the metal powder is dispersed in the plating bath to perform electrolytic plating. By doing so, the metal powder adheres to the surface of the metal protrusion 54 and becomes a seed (nucleus) during plating growth, and the metal protrusion 53 is formed. The metal powder to be dispersed is preferably in the form of fine powder in order to form fine metal protrusions 53, and has a particle size of 0.01 to 200 μm, preferably 0.1 to 50 μm.
Further, those having a thickness of about 1 to 3 μm are used.

Also, as shown in FIG.
Is preferably formed near the apex of the metal protrusion 54 from the viewpoint of increasing the number of contacts during the continuity test. In order to form in this way, it is preferable to apply a magnetic field in the apex direction of the metal protrusion 54, that is, in the hole forming direction to perform the electrolytic plating. The strength of the magnetic field at this time is about 1 kilogauss to 15 kilogauss, preferably about 2 kilogauss to 5 kilogauss. In addition, when performing electrolytic plating by applying a magnetic field,
As the metal powder dispersed in the plating solution, a magnetic metal such as nickel or cobalt is used.

As another method, by spraying a plating solution in which a metal powder is dispersed onto the surface of the formed metal protrusion 54 with a circulation pump or the like, the metal protrusion 54 is coated on the surface thereof. There is a method of forming seeds for forming 53.

Further, as another method, there is a method of performing electrolytic plating while applying ultrasonic waves to the plating bath. In this case, it is preferable from the viewpoint of the formability of the metal protrusion 53 that the surface of the metal protrusion 54 be activated by etching treatment or the like.

FIG. 7 is a sectional view showing a continuity test of an object to be inspected using the continuity test apparatus according to the present invention. In FIG. 7, the continuity inspection apparatus T1 is interposed between two ICs 71 and 72 which are the inspected objects, and the surfaces of the respective ICs 71 and 72 on which the aluminum electrodes 61 and 62 are formed are the continuity inspection apparatus T1. It is arranged so as to face. Each IC7
The aluminum electrodes 61 and 62 are moved so that the aluminum electrodes 61 and 62 are located close to the continuity inspection device T1.
After contacting each bump 51, 52 of
When 1 and 72 are displaced, a load is applied to each bump 51 and 52. The load is the conductive circuit 1 of the continuity inspection device T1.
Acts on the arrow A1, A2 direction. As a result, the conductive circuit 1 is distorted in the arrow A1 and A2 directions together with the insulator layer 2,
A load acts on each of the bumps 51 and 52 in the directions of arrows B1 and B2. Each bump 51, 52 and each aluminum electrode 61,
62 is an aluminum oxide layer 81, 82 which is an insulating layer.
As shown in FIG. 8, the bump 51 scrapes a part of the aluminum oxide layer 81 on the aluminum electrode 61 by a frictional force so that the bump 51 and the aluminum electrode 61 come into direct contact with each other. . in this way,
Conduction between the aluminum electrodes 61, 62 and the bumps 51, 52 is ensured, and the reliability of the conduction inspection of the ICs 71, 72 is improved.

[0036]

As described above, according to the continuity inspection apparatus of the present invention, for example, I, which is a circuit of the object to be inspected.
It is possible to remove the oxide formed on the aluminum electrode of C and the insulating layer due to adhesion, transfer, etc., and the conduction between the aluminum electrode and the bump, which is the contact portion, is ensured, and the reliability of the continuity test is improved. The property is improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a continuity inspection device of the present invention.

FIG. 2 is a partial cross-sectional view showing a modified example of a bump.

FIG. 3 is a partial cross-sectional view showing another modified example of the bump.

FIG. 4 is a partial sectional view showing still another modified example of the bump.

FIG. 5 is a sectional view showing another embodiment of the continuity inspection device of the present invention.

FIG. 6 is a cross-sectional view showing a manufacturing process of the continuity inspection device according to the present invention.

FIG. 7 is a cross-sectional view showing a continuity inspection of a device under test using the continuity inspection device according to the present invention.

FIG. 8 is a partial cross-sectional view showing a state where the aluminum oxide layer 81 on the aluminum electrode 61 is scraped off.

FIG. 9 is a view showing a conventional mechanical probe 80.

FIG. 10 is a partial cross-sectional view showing a conventional membrane probe 90.

[Explanation of symbols]

 1 Conductive Circuit 11, 12 Surface of Conductive Circuit 2 Insulator Layer 21, 22 Surface of Insulator Layer 41, 42 Conductive Path 51, 52 Bump (Contact Point) 61, 62 Aluminum Electrode (Circuit) 71, 72 IC (Inspected) Body) T1, T2 Continuity inspection device

Claims (3)

[Claims] 1. A conductive circuit for conducting a continuity test of an object to be inspected is embedded in a flexible insulating layer, and a pair of conductive paths that are offset in the plane direction of the conductive circuit are formed from the surface of the conductive circuit. A continuity inspection device, wherein contact portions extending in opposite directions and contacting a circuit of the device under test are connected to the conduction path, respectively. 2. The continuity inspection device according to claim 1, wherein the contact portions are formed so as to protrude outward from the surface of the insulator layer. 3. The continuity inspection device according to claim 1, wherein the contact portion is a protrusion made of a bump-shaped hard metal.