PROBE FOR ELECTRICAL TEST AND PROBE ASSEMBLY

Abstract

A probe for electrical test comprises a probe body having a base end attached to a support base plate through a solder and a front end continuous with said base end and a surface layer showing a conductivity higher than that of the probe body and a solder wettability higher than that of the probe body and extending on the surface of the probe body from the base end to the front end. In the vicinity of the base end of the surface layer, a shield region having a smaller solder wettability than that of the surface layer is formed across the surface layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation showing an embodiment of a probe of the present invention.

FIG. 2 is a section obtained along the line II-II in FIG. 1.

FIG. 3 is a partial perspective view schematically showing a connecting process of the probe of the present invention to an electric wiring path.

FIG. 4 is a view similar to FIG. 2 showing another embodiment of the probe of the present invention.

FIG. 5 is a view similar to FIG. 2 showing still another embodiment of the probe of the present invention.

FIG. 6 is a bottom view of the probe assembly with the probes of the present invention incorporated therein.

FIG. 7 is a front elevation of the probe assembly with the probes of the present invention incorporated therein.

FIG. 8 is a view similar to FIG. 2 showing a conventional probe.

Claims

1. A probe for electrical test comprising: a probe body having a base end attached to a support base plate through a solder and having a front end continuous with the base end; anda surface layer showing a conductivity higher than that of said probe body and a solder wettability higher than that of said probe body, said surface layer extending from said base end to said front end on the surface of said probe body, wherein in the vicinity of said base end of said surface layer a shield region with the solder wettability smaller than that of said surface layer is formed across said surface layer.

2. A probe claimed in claim 1, wherein said probe body has a mounting portion including said base end, and a rising portion extending from said mounting portion to the side opposing the side where said base end is located, wherein said shield region is formed in the vicinity of said rising portion in said mounting portion so as to prevent said solder from spreading to wet from said mounting portion to said rising portion.

3. A probe claimed in claim 1, wherein said probe body is formed in a flat plate-like state so that said mounting portion and said rising portion are formed flush with each other, and wherein said surface layer is continuously formed along at least one face of said probe body from said mounting portion to said rising portion.

4. A probe claimed in claim 1, wherein said solder is formed as a solder layer on said surface layer closer to the side of said base plate rather than to said shield region in said mounting portion prior to mounting of said probe body on said support base plate.

5. A probe claimed in claim 1, wherein said probe body further has an arm portion extending laterally from said rising portion, its terminal end defining said front end, and wherein said front end is provided with a tip projecting longitudinally to the side opposing the side where said base end is located.

6. A probe claimed in claim 1, wherein said probe body is made of a metal material superior to said tip in high tenacity, and wherein said tip is made of a metal material superior to said probe body in hardness.

7. A probe claimed in claim 5, wherein said probe body is made of nickel, its alloy or phosphor bronze, said surface layer is made of gold, said shield region is made of nickel or its alloy, and wherein said solder is made of tin or its alloy.

8. A probe claimed in claim 6, wherein the surface of said shield region is oxidized so as to further lower the solder wettability.

9. A probe assembly comprising a support base plate having a plurality of mounting lands, and the plural probes claimed in claim 1 with their base ends attached like a cantilever to the corresponding attachment lands through a solder.