Matched test structures for accurate characterization in millimeter wave range

This paper, presents a novel methodology for small signal equivalent circuit extraction suitable for high frequency characterization up to mm-wave range. This methodology allows the de-embedding and the extraction of RF characteristics by the use of a smart matching at 50Ω of the transistor connected in GSG probe pads. The method has been validated first on a test module based on RFMOS transistor fabricated in BiCMOS 0.25μm technology from NXP Semiconductors. The results of matched RFMOS transistors at 30.5GHz are presented here and show good agreement between measurements/extractions and calculations (e.g. for C_gs). Second, a bipolar transistor matched test structure is investigated. An improvement of transmission gain of matched test structured from -12dB to -0.2dB has been found using measurements and simulated data.