3D EM Characterization of Wafer Probes

The following paper describes a method to characterize wafer probes using a 3D EM simulator. Rather than following the traditional method of building a custom test fixture for different probe setups and measuring the S-parameters, this 3D EM characterization method yields multi-port S-parameters of a specific probe structure by utilizing simulations. For a standard characterization, the S-parameters can be a four-port S-parameter matrix for two selected probe pins. This matrix can be used directly by many RF design tools for design and analysis, and can be used to extract the equivalent circuit models of probes (if needed). An agreement has been obtained between data from the 3D EM characterization and the traditional method. In contrast to traditional methods, the 3D EM characterization method provides a fast and flexible technique to obtain an RF model of probes.