This article reports the investigation results of long-term stability tests on on-wafer measurement systems in frequency ranges up to 325 GHz conducted by the NMIJ-AIST. The radio frequency (RF) probe coordinates in the $X$ -, $Y$ -, and $Z$ -directions, and the tilt angle is automatically adjusted by performing RF signal detection. Calibrations and verification processes were repeated for over a year. The novelty of the study is that it optimizes measurement procedures for the test, demonstrates a long-term stability test, and compares the evaluated long-term stability to the effects of probe model, absorber, and calibration method. The standard deviation of the measured reflection coefficient ranged between −32 to −70 dB in magnitude, and 0°–10° in phase. The standard deviation of the measured transmission coefficient ranged from −43 to −80 dB and from 0.2°–2.7° in phase. The refined procedures contributed to improve the measurement reproducibility compared to the previous report. Furthermore, the effects of the chuck material and the calibration method were larger than long-term stability.

中文翻译：

---

在高达 325 GHz 的频率范围内对晶圆上测量系统进行长期稳定性测试

本文报告了 NMIJ-AIST 在高达 325 GHz 的频率范围内对晶圆上测量系统进行的长期稳定性测试的调查结果。射频 (RF) 探头坐标在 $X$ -, $Y$ -， 和 $Z$ -方向，并通过执行射频信号检测自动调整倾斜角度。校准和验证过程重复了一年多。该研究的新颖之处在于它优化了测试的测量程序，演示了长期稳定性测试，并将评估的长期稳定性与探头模型、吸收器和校准方法的影响进行了比较。测量反射系数的标准偏差在幅度上介于 -32 至 -70 dB 之间，相位介于 0° 至 10° 之间。测得的传输系数的标准偏差范围为 -43 到 -80 dB，相位范围为 0.2°–2.7°。与之前的报告相比，改进的程序有助于提高测量的重现性。此外，