JP2002148279A - Coaxial probe for electrical inspection - Google Patents

Abstract

(57) [Problem] To provide a coaxial probe for electrical inspection with higher definition than before. A coaxial probe for electrical inspection according to the present invention comprises a conductive wire, an insulating coating layer covering an outer periphery of the conductive wire, a conductive coating layer covering an outer periphery of the insulating coating layer, and a conductive coating layer.
The outer end of one probe has only the tip of the center conductive wire 1 protruding from each outer coating layer so that it can easily come into contact with the object to be inspected. At the end of the other probe, the center conductive wire 1 is the longest, and each coating layer is shortened toward the outside, so that the center conductive wire 1 and the conductive coating layer 3 are easily connected to separate electrodes.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coaxial probe for electrical inspection used for an electrical inspection jig for performing electrical inspection of various circuit boards and semiconductor circuit elements.

[0002]

2. Description of the Related Art Printed circuit boards and substrates for various semiconductor packages (TAB (tape automated bonding), BGA (ball grid array), CS
Probes for electrical inspection jigs for P (chip size package) and semiconductor circuit elements include a spring probe and a rigid probe.

The spring probe has a coaxial structure of a conductive core material, an insulating coating layer, a conductive coating layer, and an insulating coating layer from the center side so that it can cope with high-frequency electrical inspection. There is. However, even if the diameter of the probe itself is small, it is about 1 mm, and if the distance between the electrodes of the object to be inspected is higher than that, it is difficult to perform inspection by batch contact. If electrical inspection at high frequency is required for such high-definition inspection objects,
At present, a flying probe method in which several probes are moved to sequentially contact electrodes of an object to be inspected for inspection is used, and there is a problem that the inspection takes time.

[0004]

SUMMARY OF THE INVENTION The present invention has been devised in view of the above problems, and has as its object to provide a coaxial probe for electrical inspection with higher definition than before.

[0005]

According to the present invention, in order to achieve the above object, among probes used in an electrical inspection jig for performing electrical inspection of various circuit boards and semiconductor circuit elements, a central one of the probes is used. A coaxial cable-like electrical inspection coaxial probe comprising an insulating coating layer covering the outer periphery of the conductive wire, a conductive coating layer covering the outer periphery, and an outer insulating coating layer covering the outer periphery. At the end, only the center conductive wire tip protrudes beyond the outer coating layers to make it easier to contact the object to be inspected. At the other probe end, the center conductive wire is the longest, and each coating layer is A coaxial probe for electrical inspection, characterized in that the length of the coaxial probe is made shorter so that the center conductive wire and the conductive coating layer can be easily connected to different electrodes.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing the configuration of an embodiment of the coaxial probe for electrical inspection according to the present invention. The coaxial probe for electrical inspection 10 of the present invention includes a conductive wire 1, an insulating coating layer 2 covering the outer circumference of the conductive wire 1, a conductive coating layer 3 covering the outer circumference of the insulating coating layer 2, and an outer circumference covering the outer circumference of the conductive coating layer 3. It is composed of the insulating coating layer 4 and has a smaller diameter than the conventional one. At the end of one probe, only the tip of the center conductive wire 1 protrudes from the outer coating layers to make it easier to contact the object to be inspected, and the other end of the probe has the center conductive wire 1 most. Longer, each coating layer is shorter on the outside, so that the center conductive wire 1 and conductive coating layer 3 can be easily connected to separate electrodes.

The conductive wire 1 is made of a metal such as copper, gold or beryllium copper, or a conductive material such as carbon fiber. If necessary, a plating layer for increasing conductivity or contact stability or preventing rust, or a thin film layer having another function may be provided on the surface.

The insulating coating layer 2 has a role of protecting the conductive wire 1 and insulating between the conductive wire 1 and the conductive coating layer 3. As the material of the insulating coating layer 2, various polymer materials such as Teflon (registered trademark) and enamel can be used. The material of the insulating coating layer 2 is initially liquid, so that the conductive wire 1 is dipped and then pulled up or sprayed to form a coating film on the conductive wire 1 and then dried to form the insulating coating layer 2. To form

The conductive coating layer 3 can be formed using a conductive material such as copper, gold, nickel, chromium or the like by a process such as electroless plating, electrolytic plating, sputtering, vapor deposition or a combination of these processes.

The outer insulating coating layer 4 is formed by the same material and the same forming method as the insulating coating layer 2.

The tip 1A of the conductive wire 1 which is in contact with the test object at one end of the coaxial probe 10 for electrical inspection is connected to the conductive wire 1
Project from the other coating layers, and only the tip 1A thereof comes into contact with the test object. Further, the tip shape of the conductive wire 1 on the inspection object side is shaped into a plane, a hemisphere, a cone, a triangular pyramid or the like as necessary depending on the properties of the inspection object.

At the leading end 1B on the other end of the coaxial probe 10 for electric inspection to the wiring at the other end, the conductive wire 1 is connected to an electrode for connection to an electric signal input / output circuit, and to the conductive coating layer 3.
Is the longest conductive wire 1 at the center in order to facilitate separate connection to electrodes for connection to GND (earth). Hereinafter, an insulating coating layer 2, a conductive coating layer 3, an outer peripheral insulating coating layer Shorten in order of 4.

The diameter of the coaxial probe 10 for electrical inspection is determined by the diameter of the conductive wire 1 and the thickness of the insulating coating layer 2, the conductive coating layer 3, and the outer insulating coating layer 4. For example, a metal wire having a diameter of about 40 μm can be used as the conductive wire 1. The thickness of the insulating coating layer 2 and the outer insulating coating layer 4 is 10 to 15 μm.
m, the conductive coating layer 3 can be formed with a submicron thickness for sputtering or vapor deposition, and about 10 μm for plating. Therefore, at present, 80 to 120 μm
It is possible to manufacture a coaxial probe 10 for electrical inspection of about m.

The electric test coaxial probe 10 can be directly incorporated into an electric test jig having the same configuration as that used for a conventional rigid probe.

[0015]

Since the diameter of the coaxial probe for electrical inspection of the present invention is smaller than that of the conventional one, if an electrical inspection jig is manufactured using this coaxial probe, a test object with higher definition than the conventional one can be obtained. As a result, high-frequency electrical inspection can be performed by batch contact, and the inspection time can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of an embodiment of a coaxial probe for electrical inspection according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Conductive wire 1A ... Tip of one conductive wire of electric test coaxial probe 1B ... Tip of the other conductive wire of electric test coaxial probe 2 ... Insulating coating layer 3 ... Conducting coating layer 4 ... Outer insulating coating layer 10 Coaxial probe for electrical inspection

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G003 AA07 AE03 AG03 AG05 AH05 2G011 AA22 AB06 AB09 AC32 AE03 4M106 AA01 AA02 AA04 BA01 DD03 DD15

Claims (1)

[Claims] 1. A probe used for an electrical inspection jig for electrical inspection of various circuit boards and semiconductor circuit elements, an insulating coating layer covering an outer periphery of a center conductive wire and a conductive coating covering an outer periphery further. A coaxial probe for electrical inspection in the form of a coaxial cable, comprising a layer and an outer insulating coating layer that further covers the outer circumference, and the end of one probe is such that only the center conductive wire tip is higher than the outer coating layers. The end of the other probe has the longest conductive wire at the center, and each coating layer is shortened toward the outside, so that the center conductive wire and the conductive coating layer are separate electrodes. A coaxial probe for electrical inspection, characterized by being easily connected to a probe.