This project supports the microwave, telecommunications, computing, and emerging nanoelectronics industries through research and development of high-frequency microwave metrology for micrometer-scale and nanoscale electrical devices. This requires the development of microwave metrology in rectangular waveguide and printed transmission lines to 750 gigahertz and pulsed metrology in coaxial, rectangular waveguide, and on-wafer transmission lines to 400 gigahertz for microwave signal and signal source characterization, wireless systems, high-speed microprocessors, and high-speed nanocircuits and interconnects, and the telecommunications industry. The work is interdisciplinary and relies on strong collaborative efforts with the Optoelectronics Division.
The rapid advance in the speed of modern telecommunications and computing systems drives this project. Characterizing signal integrity in microprocessors requires at least 10 gigahertz of calibrated measurement bandwidth on structures fabricated on a nanoscale. Limited available bandwidth is pushing wireless systems into the millimeterwave region of 30 to 100 gigahertz, where accurate microwave signal and signal source characterization is difficult. Optical links operating at 40 gigabits per second require electrical metrology to 110 gigahertz. Emerging high-speed digital circuits with clock rates of over 100 gigahertz require electrical metrology to 400 gigahertz. These extraordinary advances in technology require new highspeed coaxial and on-wafer microwave signal and waveform measurements. Because the speed of the devices is often linked to size, it is important to develop this high-speed metrology at both conventional IC and nanoscale dimensions and at both conventional and high impedances.
Coaxial connectors pose insurmountable economic hurdles for high-speed telecommunications and computing. For example, a single coaxial adapter that supports frequencies to 110 gigahertz costs upwards of $1000. This project focuses on the only feasible alternative: high-speed on-wafer metrology. The project's initial focus on developing metrology for on-wafer network analysis for MMICs has been expanded to include metrology for silicon ICs and differential interconnects. More recently the project has further expanded the focus to noninvasive probing on a nanoscale and to ultra-high-speed modulated microwave signal, signal-source, and waveform characterization.