A Thru-Halfthru-Short De-Embedding Method for Millimeter-Wave On-Wafer HBT Characterization

In this letter, a cascade-based de-embedding method with thru-halfthru-short structures is presented for millimeter-wave on-wafer device characterization. Distributed effects of interconnect, discontinuity between pad and interconnect, and transistor-access-via-holes are all well considered using only three dummy structures, and forward coupling is also investigated. By providing both extracted junction capacitors and S-parameter results of 0.5-μm InP DHBT transistor using proposed and existing de-embedding methods up to 220 GHz, better high frequency performance and particularly 21° improvement in phase accuracy for S
₁₁
as well as 12° for S
₂₁
at 220 GHz are obtained compared with the state-of-the-art cascade-based method.