2001 年 67 巻 8 号 p. 1239-1243
The fritting of thin oxide on metal surface is indispensable to realize micromachined probe cards, because each microprobe cannot endure the force required to break the oxide on the surface of IC pads mechanically. In order to clarify the force required for fritting-contact make, the relationship between contact forces and the fritting has been investigated using an atomic force microscope (AFM) system and micromachined cantilever probes with a pyramidal tip. The following results are obtained on the fritting between electroplated Au tip and Al or Cu films: (1) A stable low-resistance contact to Al and Cu films can be obtained without applying contact forces larger than 30μN, when the applied voltage is larger than 15V. (2) Then the adhesion forces between the probe and films are less than 30μN. (3) The fritting contact of Cu film is easily obtained with low contact force and low applied voltage compared to that of Al film. (4) Contact resistance decreases with increasing the fritting current. In addition, it is concluded that probe cards consisting of micromachined cantilevers can be applied to the test of peripheral pad configuration IC with the pad pitch of 20μm, in consequence of simple calculations.