Automated Performance of On-wafer Calibration and Characterization Using Non-contact Probes

We present the repeatability performance of automated non-contact on-wafer probing for millimeter-wave and terahertz band applications. Based on the antenna-coupled non-contact probing approach, we incorporated computer control into the existing hardware to automate the test wafer manipulation. A digital microscope with pattern recognition is used to precisely control the alignment of on-wafer antennas at the test ports to minimize positioning repeatability errors. Commercial-off-the-shelf micro-positioners used in our system allow for sub-micron repeatability in device alignment, significantly improving repeatability. Furthermore, the non-contact system does not need vertical translation (conventionally used for probe landing), thus can achieve highly repeatable measurements. The repeatability performance of the automated system presented here is thus limited by the drift of the frequency extenders used.