A Novel 24-GHz Bandwidth Coaxial Probe

An electrical probe based on specially designed coaxial tips is shown to have 24-GHz bandwidth. It can be used to test high-speed signal propagation on planar or nonplanar chip or package interconnection structures with signal/ground pads as small as 50 µm. The detailed fabrication procedure, characterization, and use of the probe are presented. A variation of the design has 500-Ω input impedance and a bandwidth of 19 GHz. © 1990 IEEE