Accuracy Improvement of On-wafer Measurement at Millimeter-wave Frequency by a Full-automatic RF probe-tip Alignment Technique

The paper presents an innovative measurement technique to improve measurement reproducibility in on-wafer measurement at millimeter-wave frequency. The measurement system, established by a full-automatic probe station and its control program, achieves high-repeatable measurement by RF signal detection technique to determine probe-tip position in X, Y, and Z-axes. Reproducibility of setting distance between two probes in multi-line TRL calibration was improved less than 3 μm. It achieved almost quarter than distance reproducibility of probe-tip in conventional manual alignment. In the case of a 75 Ω transmission line measurement, the paper demonstrated reproducible distance determination between probe-tip produced to precision and repeatable measurement compared to conventional manual probing technique.