Keysight Technologies E4991A RF Impedance Material Analyzer

Keysight Technologies E4991A RF Impedance/Material Analyzer is an RF impedance and material characterization instrument that measures the complex impedance of solid materials and components from 1 MHz to 3 GHz, enabling extraction of dielectric properties such as dielectric constant and loss tangent when used with appropriate test fixtures. It is designed for comprehensive material and component analysis across RF/microwave frequencies, including on‑wafer measurements with a probe‑station setup via the E4991A‑010 Probe Station Connection Kit and compatible coaxial/test fixtures. The instrument provides broadband impedance measurements (Z) across the sweep, conveying resistance, reactance, and phase information to quantify material response, with optional DC bias to study bias‑dependent behavior. Typical applications include characterizing dielectric substrates, ceramics, polymers, and composites for RF circuit performance, laminates, and other materials where impedance and dielectric properties influence device behavior.