JPH06308196A - Test head structure - Google Patents

Abstract

PURPOSE:To provide a test head structure in which the alignment of a probe and a circuit electrode to be inspected is facilitated, no positional deviation occurs during inspecting and which has excellent contact reliability. CONSTITUTION:An insulation film 1 has a recess 11 on a surface and a contact 2 with an element to be detected and formed in a bottom of the recess 11 in such a manner that the recess 11 is desirably formed in multiple stages of two or more stages. A partition wall is formed at the periphery of the contact 2 with the element to be detected, and the recess 11 becomes an aligning unit and/or a container of a circuit to be inspected. Accordingly, continuity test of a semiconductor element, a semiconductor device, circuit wiring board, etc., can be easily and effectively conducted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a test head structure, and more particularly to a test head structure useful for inspecting semiconductor elements, semiconductor devices, circuit wiring boards and the like.

[0002]

2. Description of the Related Art In recent years, the number of electrodes of semiconductor devices and circuit wiring boards has increased and the pitch thereof has been increasing year by year with the development of electronic equipment, and in particular with the densification of semiconductor integration and packaging technology. Conventionally, such semiconductor elements, semiconductor devices,
There was a needle type mechanical probe as a device for conducting a continuity test of circuit wiring boards, etc., but when using this, the needle diameter should be changed in response to the higher density of the semiconductor device and circuit wiring board structures as described above. There is a problem that the needle has to be made small, and as a result, the needle bends when it is repeatedly used and comes into contact with a conductor portion not to be inspected to cause a short circuit. In order to solve such a problem, as described in JP-A-3-237369, a conductive path is provided independently in the thickness direction of an insulating film, and one end of the conductive path is covered with a conductive material. A test head structure has been proposed which uses a circuit wiring board in which a circuit made of a conductor is formed at the tip of the other end in contact with the sample. In this structure, the bump-shaped contact portion serves as an inspection probe to contact the circuit to be inspected to inspect the conduction.

[0003]

However, in the above-described test head, it is difficult to align the probe with the electrode of the circuit to be inspected, and a positional deviation occurs during the inspection so that the electrodes do not come into contact with each other. Therefore, there is a problem that contact reliability is insufficient. The present invention has been made in view of such circumstances, and it is possible to easily align the probe and the electrode of the circuit to be inspected, and to obtain a reliable conductive contact without displacement during inspection. It is an object of the present invention to provide a test head structure having excellent contact reliability.

[0004]

DISCLOSURE OF THE INVENTION The inventors of the present invention have formed a concave portion on the surface of an insulating film in a test head structure and formed a contact portion with a subject at the bottom of the concave portion. It was found that the above-mentioned object can be achieved by adjusting the position of the inspection target circuit electrode to the inspection target circuit electrode, accommodating the inspection target circuit board, or preventing the displacement of the contact portion under inspection from the inspection target circuit electrode, and complete the present invention. Came to do. That is, the test head structure of the present invention has a structure in which a circuit made of a conductor provided on one surface of the insulating film and a contact portion between the subject and the object provided on the other surface of the film are electrically connected. The insulating film has a concave portion on the surface, and the contact portion with the subject is formed on the bottom portion of the concave portion, and preferably the concave portion has two or more steps. Is formed in a multi-stage shape, and partition walls are formed around each of the contact portions with the subject, and the recesses serve as alignment portions and / or accommodating portions of the circuit to be inspected.

[0005]

Next, the present invention will be described in detail. The test head structure of the present invention basically includes an insulating film in which a concave portion is formed, a circuit made of a conductor, and a contact portion with a subject.

In the present invention, the insulating film is not particularly limited as long as it is a film having electric insulating properties, and examples thereof include polyester resin, epoxy resin, urethane resin, polystyrene resin,
Polyethylene resin, polyamide resin, polyimide resin, acrylonitrile-butadiene-styrene (AB
S) Thermosetting resins and thermoplastic resins such as copolymer resins, polycarbonate resins, silicone resins and the like can be mentioned. Among these resins, it is particularly preferable to use a polyimide resin from the viewpoint of heat resistance and mechanical strength.
The thickness of the insulating film is not particularly limited, but in order to have sufficient mechanical strength and flexibility as a film, a concave portion is formed and a circuit board to be inspected or a concave portion is formed in the concave portion. In order to obtain a sufficient positioning effect by fitting the circuit electrodes to be inspected, the range of 2-500 μm, preferably 10-150 μm
It is preferable to set in the range of m.

The conductive substance which is the material for forming the contact portion with the subject is not particularly limited as long as it has conductivity, and gold, silver, copper, nickel, cobalt, lead and tin are used. A conventionally known metallic conductive material such as chromium, chromium, or tungsten is used.

Examples of the circuit forming material formed on the insulating film include conductive materials such as various metals such as gold, silver, copper, nickel and cobalt, and various alloys containing these as the main components. This circuit is provided by means known per se.

The method of conducting the contact portion and the circuit is not particularly limited, but normally a through hole is provided in the thickness direction of the insulating film, and the through hole is filled with a conductive substance to form a conductive path. Is formed so that the contact portion and the circuit are electrically connected by this conduction path.

The conductive path may be formed of the same conductive material as the material for forming the contact portion or another conductive material, but is usually formed of the same material. For forming this conductive path, a means known per se may be used.

[0011]

EXAMPLES Next, the present invention will be described in more detail based on examples. FIG. 1 is a sectional view showing an embodiment of the test head structure of the present invention. In the figure, F is a circuit wiring board for a test head, and at least one through hole 12 is provided in the circuit contact area of the insulating film 1 having the circuit 3 made of a conductor on one surface and in the vicinity thereof. The through hole 12 is filled with a conductive substance and the conductive path 4
Is formed, and the contact portion 2 made of a conductive substance with the subject is formed so as to protrude from the surface of the insulating film 1.
As a feature of the present invention, the insulating film 1 has a concave portion 1 on the surface.
1 and a contact portion 2 for contacting the subject with the bottom of the recess 11
Are formed.

The test head circuit wiring board F can be manufactured, for example, as follows. (1) First, as shown in FIG. 2A, the insulating film 1 and the conductor layer 30 are laminated to produce a two-layer base material. As a method of laminating the insulating film 1 and the conductor layer 30, a method of forming a conductor layer on the insulating film by a plating method, a sputtering method, a CVD method, or the like, or a conductor foil as a conductor layer is used. Alternatively, an insulating material may be coated on the conductive foil and solidified to form an insulating material layer.

(2) Next, the circuit 3 is formed as shown in FIG. The circuit 3 is obtained by forming a circuit pattern on the conductor layer 30 using a photosensitive resin and performing etching.

(3) Further, as shown in FIG.
A recess 11 is formed on the surface of the insulating film 1. The size and shape of the recess 11 are determined according to the size and shape of the circuit board to be inspected, but when the circuit board to be inspected is accommodated, the side surface of the circuit board to be inspected and the side wall of the recess 11 are formed. A gap of 1 to 100 μm, preferably 3 to 20 μm is provided therebetween. If this gap is less than 1 μm, it becomes difficult to fit the circuit board to be inspected into the recess 11, whereas if it exceeds 100 μm, the effect of positioning the recess 11 and the effect of preventing displacement are not preferable. The depth of the recess 11 varies depending on the thickness of the circuit board to be inspected and the insulating film 1 to be mounted, but is set to at least 3 μm, preferably 10 μm or more so that the circuit board to be inspected can be reliably accommodated. In addition, the thickness of the insulating film 1 is set to 90% or less, preferably 70% or less so that the mechanical strength of the insulating film 1 is not insufficient.

As the method for forming the concave portion 11, mechanical processing, plasma processing, laser processing, lithography using the photoreactive insulating film 1 or a resist having a different chemical resistance from the insulating film 1 is used. The method such as chemical etching used may be mentioned. Among them, it is preferable to perform half etching or perforation by irradiation with an excimer laser whose pulse number and energy amount are controlled.

(4) Thereafter, as shown in FIG.
Through holes 12 are formed in a predetermined region of the bottom surface of the recess 11 in the thickness direction of the film. The through hole 12 is formed so as to penetrate only the insulating film 1.
It is formed so that the conductor circuit 3 therebelow is exposed from the opening 2. The diameter of the through hole 12 is 2 to 20.
The thickness is set to 0 μm, preferably 5 to 50 μm. Through hole 1
If the pore diameter of 2 is less than 2 μm, the conductivity of the conduction path 4 formed inside becomes insufficient, while if it exceeds 100 μm, the contact portion 2 with the subject formed at the tip of the conduction path 4 becomes large. This is not preferable because it cannot be applied to a high-density circuit to be inspected. The through hole 12 can be formed by a method similar to the method of forming the recess 11.

(5) Next, as shown in FIG. 2E, a protective insulating layer 5 is formed on the outer surface of the conductor circuit 3, and the through hole 1 is formed.
2 is filled with a conductive substance to form a conductive path 4, and a contact portion 2 with the subject is formed. The filling of the conductive material into the through holes 12 can be performed not only by physically embedding the conductive material, but also by chemical deposition or the like. Specifically, a CVD method, a plating method, a method of immersing in a molten bath of a conductive substance and pulling it up to deposit the conductive substance, and the like can be mentioned. In addition, the protective insulating layer 5
A conventionally known method may be used as the forming method.

The contact portion 2 with the subject is formed in a bump shape as shown in FIG. 2 (e) if the shape of the subject is a flat shape, and if the shape of the subject is a bump shape. It is preferably formed in a flat shape. Further, the height of the contact portion 2 is not particularly limited, but the concave portion 11 of the insulating film 1
It is preferable to set the depth lower than the depth of the recess 11 and within the range of several μm to several tens of μm so as not to impair the alignment effect of the above.

(6) After that, the protective insulating layer 5 is removed by a conventional method to obtain a test head circuit wiring board F as shown in FIG.

When the contact portion 2 for contacting the subject is formed in a bump shape as described above, the protruding shape is such that the protruding end edge portion exceeds the opening edge of the through hole 12, as shown in FIG. You may make it the head shape of what is called a rivet tack which extends laterally. In this case, the head portion has an effect of preventing the conductive path 4 from falling off.

When the conductive path 4 and the contact portion 2 with the subject are formed by using another conductive material, for example, as shown in FIG. 4, a structure using three kinds of conductive materials is used. Good. That is, an inexpensive metal substance such as copper is used for the portion of the through hole 12 that contacts the circuit 3 to form the first layer 41, and the contact portion 2
Is a third layer 43 made of gold or the like having high connection reliability, and the second layer 42 is located between the first layer 41 and the third layer 43.
For this, nickel or the like is used as a barrier metal substance. Further, it is not limited to the structure using the above-mentioned three kinds of conductive substances, and may be formed into a structure using two kinds or four or more kinds of conductive materials.

Further, the conducting path 4 may be formed in an oblique direction of the film thickness direction as shown in FIGS. 5 and 6, and in this case, the pressure applied to the contact portion 2 serving as the probe can be relieved. Therefore, the life of the contact portion 2 can be extended.

Further, as shown in FIG. 7, a protrusion 21 having a smaller diameter (or needle shape) can be formed on the contact portion 2 with the subject. According to this, it is possible to add the action of breaking through the metal oxide film of the circuit electrode to be inspected to the contact portion 2.

FIG. 8 shows a state in which a small circuit to be inspected P such as a semiconductor element is fitted in the recess 11 and the circuit electrode to be inspected D is brought into contact with the contact portion 2 to be a probe to conduct a continuity test. It is a schematic diagram which shows an example. From the figure, it can be seen that by fitting the circuit under test P into the concave portion 11, the alignment can be easily performed and the positional deviation in the horizontal direction can be prevented.

When the circuit board to be inspected is large, as shown in FIG. 9, the small recess 1 is formed only at the position corresponding to the circuit electrode to be inspected.
1'is formed, and the contact portion 2 with the subject is formed at the bottom of the small recess 11 ', and partition walls are formed around each contact portion by the small recess 11'. Good. The size and shape of the small-sized recess 11 ′ is similar to that of the recess 11 between the side surface of the circuit electrode under test and the side wall of the small recess 11 ′ when the circuit electrode under test is housed. The gap should be ˜100 μm, preferably 3-20 μm. The depth of the small recess 11 'varies depending on the thickness of the circuit electrode to be inspected or the insulating film 1 to be mounted, but at least 3 μm, preferably 10 μm or more so as to reliably accommodate the circuit electrode to be inspected. Is set to 90% or less of the thickness of the insulating film 1 so that the mechanical strength of the insulating film 1 is not insufficient.
It is preferably set to 70% or less. The small recess 11 ′ is formed by a method similar to the method of forming the recess 11.

The small-sized recess 11 'enables a continuity test to be performed as shown in FIG. In this case, by fitting the circuit electrode D'to be inspected into the small recess 11 ', the alignment can be easily performed, and the displacement in the horizontal direction can be prevented.

Further, FIG. 11 shows a test head structure in which a recess 11 into which a small circuit board P is fitted and a small recess 11 'into which a circuit electrode D to be tested are fitted are combined to form a two-step recess. FIG. 9 is a schematic diagram showing the position adjustment, and more reliable position alignment and position shift prevention effects can be obtained.

FIG. 12 shows an example in which a plurality of contact portions 2 are formed in alignment on a circuit wiring board. According to this, the chance of contact between the circuit electrode to be inspected and the contact portion 2 increases, so that the test head Contact reliability can be further improved.

FIG. 13 shows a recess 11 and a small recess 1
1'is for visual confirmation for aligning the circuit electrodes to be inspected, and in addition to this, through holes 13 are formed on the insulating film 1, and the circuit board to be inspected is brought into contact with the circuit electrodes to be inspected along the groove. This is an example in which it functions as a guide groove for contacting the portion 2.

FIG. 14 shows an example in which the grounding conductor layer 6 is formed on the surface of the insulating film 1 having the recess 11.
With such a laminated structure, impedance matching can be more accurately ensured, and a circuit under test having high frequency characteristics can be dealt with. The ground conductor layer 6 has a protective layer formed in advance on the surface of the insulating film 1 on which the conductor circuit 3 is formed and inside the recess 11.
A method of removing the protective layer after the conductor layer 6 is formed by metal vapor deposition, or a metal foil having a through hole formed at a position corresponding to the recess 11 or a laminate of a metal foil and an insulating film is attached with an adhesive. It can be formed by a method or the like.

In FIG. 15, the circuit wiring board having the concave portion 11 and the circuit wiring board having no concave portion 11 are bonded by an adhesive 7
Is an example of a multi-layer structure in which each contact portion 2 and the conductor circuit 3 are connected to each other to establish conduction in the thickness direction. By increasing the number of layers, the degree of freedom in circuit wiring is increased, and it is possible to deal with higher density circuits to be inspected.

[0032]

According to the test head structure of the present invention, the insulating film has a concave portion on the surface, and the contact portion with the subject is formed at the bottom of the concave portion. Positioning can be easily performed by functioning as a groove for confirmation or by fitting a circuit board to be inspected or its electrode into the recess. Further, since the circuit board to be inspected is mounted by fitting in the recess as described above, it is possible to prevent the displacement of the contact portion and the circuit electrode to be inspected, and to obtain a reliable conductive contact to ensure contact reliability of the test head. It is possible to improve the sex. Therefore, according to the present invention, the continuity test of the semiconductor element, the semiconductor device, the circuit wiring board and the like can be easily and surely performed.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a test head structure of the present invention.

FIG. 2 is a schematic cross-sectional view showing a manufacturing process of the test head circuit wiring board of FIG.

FIG. 3 is a schematic cross-sectional view showing an example of a circuit, a conduction path, and a contact portion with a subject in the test head structure of the present invention.

FIG. 4 is a schematic cross-sectional view showing another example of a circuit, a conduction path, and a contact portion with a subject in the test head structure of the present invention.

FIG. 5 is a schematic cross-sectional view showing another example of a circuit, a conduction path, and a contact portion with a subject in the test head structure of the present invention.

FIG. 6 is a schematic cross-sectional view showing another example of the circuit, the conductive path, and the contact portion with the subject in the test head structure of the present invention.

FIG. 7 is a schematic cross-sectional view showing another example of a circuit, a conductive path, and a contact portion with a subject in the test head structure of the present invention.

8 is a schematic cross-sectional view showing a state in which a circuit board to be inspected is mounted on the circuit wiring board for a test head of FIG.

FIG. 9 is a schematic cross-sectional view showing another embodiment of the test head structure of the present invention.

10 is a schematic cross-sectional view showing a state in which an inspected circuit board is mounted on the test head circuit wiring board in FIG. 9;

FIG. 11 is a schematic cross-sectional view showing another embodiment of the test head structure of the present invention and a state in which an inspected circuit board is mounted on the test head circuit wiring board.

FIG. 12 is a schematic view showing an aspect in which a large number of conducting paths and contact portions with a subject are formed on an insulating film.

FIG. 13 is a schematic cross-sectional view showing another embodiment of the test head structure of the present invention.

FIG. 14 is a schematic cross-sectional view showing another embodiment of the test head structure of the present invention.

FIG. 15 is a schematic cross-sectional view showing another embodiment of the test head structure of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating film 11 Recessed part 12 Through hole 2 Contact part with a test object 3 Circuit 4 Conducting path F Test head circuit wiring board

Claims (4)

[Claims] 1. A structure in which a circuit made of a conductor provided on one surface of an insulating film and a contact portion with a subject provided on the other surface of the film are electrically connected to each other. A test head structure, wherein the insulating film has a concave portion on its surface, and a contact portion with the subject is formed at the bottom of the concave portion. 2. The test head structure according to claim 1, wherein the recessed portion is formed in a multi-stepped shape having two or more steps. 3. The test head structure according to claim 1, wherein partition walls are formed around each of the contact portions with the subject. 4. The test head structure according to claim 1, 2 or 3, wherein the concave portion serves as an alignment portion and / or a housing portion of the circuit under test.