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This paper presents the first calibration and measurement results of a novel wafer-level single-sweep system operating continuously up to 250 GHz. The setup combines Keysight’s NA5307A frequency extenders with MPI’s TITAN™ single-ended and differential probes, directly mounted to the extender ports, and employs MPI probe systems together with QAlibria® calibration software. Probe characterization confirmed low insertion loss and high return loss, enabling high dynamic range and stable output power at the device under test. Calibration accuracy, evaluated using the multiline TRL (mTRL) algorithm, showed reproducibility better than -40 dB across multiple operators. Measurement repeatability, verified for both single-ended and differential configurations, exhibited narrow confidence intervals. The results demonstrate accurate, repeatable, and reliable wafer-level measurements across the full 250 GHz band and provide a baseline for cross-operator and cross-laboratory data comparison.

This paper presents an interlaboratory comparison of on-wafer $S$-parameter measurements of coplanar waveguide (CPW) devices on a commercially available calibration substrate from 2.5 GHz to 220 GHz. Four laboratories participated in the study, using either conventional banded systems or novel broadband single-sweep systems. All laboratories performed “onwafer” multiline Thru-Reflect-Line (mTRL) calibrations. The resulting datasets are compared to evaluate agreement in magnitude and phase across laboratories and system types. Standard deviations across the laboratory results are calculated to quantify the reproducibility of mm-wave and sub-THz on-wafer $S$-parameter measurements under differing operators, equipment, and laboratory conditions.

This work proposes a model centric diagnostic approach in which the frequency dependent behavior of extracted device parameters is used to identify calibration related error mechanisms. Controlled virtual experiments are performed using a compact BSIM4 nMOS device model to evaluate the impact of two common calibration perturbations: errors in the calibration reference plane definition and errors in the calibration reference impedance. The resulting distortions in extracted parameters such as gate resistance $R_{g}$ and intrinsic capacitance $C_{gg}$ form characteristic diagnostic fingerprints. The predicted behaviors are validated experimentally using on wafer measurements of an nMOS device with multiple calibration implementations. The results demonstrate that different calibration assumptions produce distinct frequency dependent parameter signatures, providing a practical framework for diagnosing calibration issues in RF and mm-wave device characterization workflows.

The paper presents a method for estimating the reproducibility budget for RF probe-tip calibration on commercial calibration substrates, a critical factor for achieving reliable wafer-level measurements. This approach isolates calibration errors associated with standard location and probe contact repeatability, enabling more consistent cross-system data comparisons even with varying VNAs and probe models. The proposed method simplifies t he application of calibration uncertainty propagation tools for wafer-level experiments and highlights the value of location-dependent error estimation. Furthermore, we illustrate how the estimated calibration reproducibility error budgets can be used for reporting the measurement results of a passive verification device.

This paper presents a comparison of on-wafer $S$-parameter measurements of coplanar waveguide (CPW) devices using broadband single-sweep and conventional banded systems, up to 220 GHz. Three attenuators and a pair of loads on a commercial calibration substrate were measured using these two different types of systems in the same laboratory, and the results are reported and discussed. Overall, good agreement was observed between the two different approaches. This study benchmarks the performance of the single-sweep system against conventional banded systems using on-wafer measurements and provides insights into the equivalence of these methods for other users.

This paper presents two innovative four-port probe stations developed by FormFactor Incorporated (FFI) and MPI Corporation (MPI), and a four-port calibration standard design up to 125 GHz for the probe stations. True four-port probing at mmWave and beyond does not yet exist, but is anticipated for future multi-band wireless devices using several antennas and RF chains. The four-port probe stations are housed in the THz measurement facility at NYU and allow simultaneous probing from East, West, North, and South orientations, which presents challenges for calibration. An on-chip Short-Open-Load-Reciprocal (SOLR) calibration (cal) standard is designed leveraging UMC's 28 nm CMOS process. S/O/L standard S-parameters are extracted using a virtual multiline Thru-Reflect-Line (mTRL) cal and used to validate SOLR cal performance via simulations up to 125 GHz. The novel probing solutions from MPI and FFI, along with the SOLR cal, open up considerable opportunities for precise RF characterization across wide frequency ranges.

Precision in millimeter-wave (mmWave) device characterization is significantly i nfluenced by sy stem dr ift, particularly in setups where temperature variations are substantial. Key components of the wafer-level test system, such as mmWave frequency extenders, waveguide RF probes, and waveguide sections, are susceptible to thermal-induced drift, which directly impacts measurement accuracy and necessitates frequent recalibration. This work presents an integrated advanced ThermalShield ${ }^{\text{TM}}$ and Probe ThermalProtector ${ }^{\text{TM }}$ solution designed to stabilize the temperature of critical system components by employing active air purge shielding and active cooling of waveguide sections and RF probes. Our approach effectively reduces drift, significantly improves measurement accuracy, and enables long-term device characterization across a wide temperature range of $-40^{\circ} \mathrm{C}$ to $+175^{\circ} \mathrm{C}$ and chuck positions. We demonstrate that the proposed method reduced drift errors from as high as $80 \% E V M$ to an average of $10 \%-13 \%$, depending on test conditions, facilitating precise on-wafer measurements with minimal required recalibration.

Provides society information that may include news, reviews or technical notes that should be of interest to practitioners and researchers.

Broadband network analysis measurement are increasingly needed in 4-port and differential contexts. A GSGSG probe design and system capable of 70 kHz-220 GHz single-sweep measurements are presented that show similar raw losses (VNA port to probe tip) and measurement repeatability characteristics to two port measurements. Intra-probe coupling may be playing an uncertainty role at higher frequencies and conversion to mixed-mode parameters show changes in the repeatability statistics that may be related to correlations of the repeatability variances.

In this paper we report for the first time on progress towards establishing traceability for on-wafer measurements of planar devices using fixed-distance 1 umped-element calibrations on a commercially available coplanar calibration substrate. The uncertainty budget includes instrumentation errors, connector repeatability and calibration standard uncertainties. Preliminary results are shown for verification devices embedded in the commercial calibration substrate.

Provides society information that may include news, reviews or technical notes that should be of interest to practitioners and researchers.

This paper outlines the theoretical background and the results of advanced RF calibration procedures specially suited to support wafer level RF device characterization with mono- and/or mixed-mode interfaces. The analysis of on-wafer measurement systems bring up the benefits of using load standards, refiectometers, as well as the GSOLT-model to perform high quality device characterizations. Based on the large number of possible methods to combine two-port calibration algorithms with multiport techniques, two methods were derived and investigated focusing on on-wafer devices. The results of our experiments demonstrate the effectiveness of novel RRMT on-wafer calibration method for multiport devices.

The increasing demand for more content, services, and security drives the development of high-speed wireless technologies, optical communication, automotive radar, imaging and sensing systems and many other mm-wave and THz applications. S-parameter measurement at mm-wave and sub-mm wave frequencies plays a crucial role in the modern IC design debug. Most importantly, however, is the step of device characterization for development and optimization of device model parameters for new technologies. Accurate characterization of the intrinsic device in its entire operation frequency range becomes extremely important and this task is very challenging. This book presents solutions for accurate mm-wave characterization of advanced semiconductor devices. It guides through the process of development, implementation and verification of the in-situ calibration methods optimized for high-performance silicon technologies. Technical topics discussed in the book include: • Specifics of S-parameter measurements of planar structures • Complete mathematical solution for lumped-standard based calibration methods, including the transfer Thru-Match-Reflect (TMR) algorithms • Design guideline and examples for the on-wafer calibration standards realized in both advanced SiGe BiCMOS and RF CMOS processes • Methods for verification of electrical characteristics of calibration standards and accuracy of the in-situ calibration results • Comparison of the new technique vs. conventional approaches: the probe-tip calibration and the pad parasitic de-embedding for various device types, geometries and model parameters • New aspects of the on-wafer RF measurements at mmWave frequency range and calibration assurance.

The increasing demand for more content, services, and security drives the development of high-speed wireless technologies, optical communication, automotive radar, imaging and sensing systems and many other mm-wave and THz applications. S-parameter measurement at mm-wave and sub-mm wave frequencies plays a crucial role in the modern IC design debug. Most importantly, however, is the step of device characterization for development and optimization of device model parameters for new technologies. Accurate characterization of the intrinsic device in its entire operation frequency range becomes extremely important and this task is very challenging.This book presents solutions for accurate mm-wave characterization of advanced semiconductor devices. It guides through the process of development, implementation and verification of the in-situ calibration methods optimized for high-performance silicon technologies.Technical topics discussed in the book include: Specifics of S-parameter measurements of planar structures Complete mathematical solution for lumped-standard based calibration methods, including the transfer Thru-Match-Reflect (TMR) algorithms Design guideline and examples for the on-wafer calibration standards realized in both advanced SiGe BiCMOS and RF CMOS processes Methods for verification of electrical characteristics of calibration standards and accuracy of the in-situ calibration results Comparison of the new technique vs. conventional approaches: the probe-tip calibration and the pad parasitic de-embedding for various device types, geometries and model parameters New aspects of the on-wafer RF measurements at mmWave frequency range and calibration assurance.

The increasing demand for more content, services, and security drives the development of high-speed wireless technologies, optical communication, automotive radar, imaging and sensing systems and many other mm-wave and THz applications. S-parameter measurement at mm-wave and sub-mm wave frequencies plays a crucial role in the modern IC design debug. Most importantly, however, is the step of device characterization for development and optimization of device model parameters for new technologies. Accurate characterization of the intrinsic device in its entire operation frequency range becomes extremely important and this task is very challenging. This book presents solutions for accurate mm-wave characterization of advanced semiconductor devices. It guides through the process of development, implementation and verification of the in-situ calibration methods optimized for high-performance silicon technologies. Technical topics discussed in the book include: • Specifics of S-parameter measurements of planar structures • Complete mathematical solution for lumped-standard based calibration methods, including the transfer Thru-Match-Reflect (TMR) algorithms • Design guideline and examples for the on-wafer calibration standards realized in both advanced SiGe BiCMOS and RF CMOS processes • Methods for verification of electrical characteristics of calibration standards and accuracy of the in-situ calibration results • Comparison of the new technique vs. conventional approaches: the probe-tip calibration and the pad parasitic de-embedding for various device types, geometries and model parameters • New aspects of the on-wafer RF measurements at mmWave frequency range and calibration assurance.