Micro Four-Point Probe with Metal Tip

Abstract

A fabrication method for a metal micro four-point probe with metal tip and measurements made using this probe are presented. A novel conical metal tip etching method using silicon dioxide chamber is also introduced. Four-point-probe resolution is decided by the electrode spacing because the effective probing depth is proportional to the electrode spacing [1]. AFM (Atomic Force Microscope) cantilever type micro four-point probe can be installed in the commercial AFM to measure the sample resistivity with low contact force and high resolution [2]. The integration of a vertical tip extends the useful application of micro four-point-probe. A conductive tip can be fabricated by coating a dielectric cantilever with conductive material. However, solid electric contact between sample and cantilever tip cannot be ensured because of the possibility of tip coating material wear. The effect of conductivity loss due to wear can be reduced with a solid metal tip.