On-Wafer Measurements and Calibration at Sub-mm-Wave Frequencies Using Micromachined Probes

The first on-wafer measurements performed above 500GHz were accomplished using probes based on integrated micromachined silicon chips. The mechanics, geometry, contact tip material and calibration processes used for these probes each have significant influence on their performance as well as their use in obtaining accurate measurements. This presentation discusses the practical use and application of micromachined probes for sub-mm-wave on-wafer measurements up to 1THz, including considerations of probe skating and overdrive, contact force and resistance, measurement repeatability, and calibration. In addition, the prospects and progress towards integrating sensors and instrumentation onto the micromachined probe platform are described.