PROBE PIN AND METHOD OF MANUFACTURING THE SAME
A probe pin having a bent portion at its tip end portion is used for a probe card, the probe pin is configured such that an angle constituted by a direction of work groove generated at a time of machine-working of a tip end portion of the probe pin and a longitudinal direction of a metal wire is set to 45 degree or less, or both directions are set to be almost parallel to each other. Due to above configuration, even if the tip end portion of the probe pin is subjected to a bending work and a worked surface is formed with recessed portion, a breakage of the probe pin caused by the recessed portion existing on the worked surface and functioning as a starting point of the breakage can be effectively prevented whereby a lowering of a production yield of the probe pin can be greatly suppressed.
1 . A probe pin formed with a tapered portion which is formed by machine-working a tip end portion of a metal wire, wherein an angle constituted by a direction of groove formed by the machine-working of the tip end portion and a longitudinal direction of the metal wire is 45 degree or less.
2 . The probe pin according to claim 1 , wherein said tip end portion of the probe pin has a surface roughness Ra of 5 μm or less.
3 . A method of manufacturing the probe pin according to claim 1 , wherein the method comprising:
a preparing step for preparing a probe pin raw material by cutting a metal wire; and
a working step for forming a tapered portion by machine-working the tip end portion of the probe pin raw material;
wherein said machine-working is a grinding work in which the tip end portion of the probe pin raw material abuts against a grinding surface of a rotary-type grinding wheel whereby the tip end portion is ground, and an angle constituted by a traveling direction of the grinding surface of the grinding wheel and a longitudinal direction of the metal wire is set to 45 degree or less.
4 . The method of manufacturing the probe pin according to claim 3 , wherein said traveling direction of the grinding surface of the rotary grinding wheel is almost parallel with the longitudinal direction of the metal wire.
5 . The method of manufacturing the probe pin according to claim 3 , wherein a rotation number of the grinding wheel is set to 100 rpm to 20000 rpm.
6 . The method of manufacturing the probe pin according to claim 3 , wherein a cutting rate of the grinding stone with respect to the metal wire is 0.01 mm/sec or more and 5 mm/sec or less.
7 . The method of manufacturing the probe pin according to claim 3 , wherein a mesh size of abrasive grains contained in the grinding wheel is controlled to be 120 or more and 2000 or less.
8 . The method of manufacturing the probe pin according to claim 3 , wherein said grinding work as grinding step is performed in a state where a grinding fluid is coated onto the grinding surface of the metal wire.