InP DHBT Characterization up to 500 GHz and Compact Model Validation Towards THz Circuit Design

Abstract

We report on-wafer characterization results up to 500 GHz on a 0.4×5 µm² InP/InGaAs DHBT. The measurements were performed using an on-wafer Thru-Reflect-Line (TRL) calibration kit especially developed in this technology. The resulting measurements allowed to validate both the RF performance of the 0.4-µm InP/InGaAs DHBT fabricated by III-V Lab, featuring 390/600 GHz fT/fmax, and the HiCuM compact model towards future circuit design at submillimeter-wave frequencies thanks to 90% typical yield reached in this technology.

InP DHBT test structure optimization towards 110 GHz characterization

“…2) High quality pads (design 2) As presented in [5], this design (see Fig. 3) combines two optimization strategies to improve the on-wafer measurement accuracy up to 500 GHz.…”

“…It has been shown that measurements beyond 110 GHz are particularly difficult [4]. To perform InP DHBT characterization at higher frequencies, on-wafer thru-reflectline (TRL) calibration has been introduced along with optimized test structures [5]- [7]. This method has demonstrated excellent results.…”

InP DHBT On-Wafer RF Characterization and Small-Signal Modelling up to 220 GHz

“…However, the fact remains unchanged that accurate characterization at higher frequencies are needed to confirm the cut-off frequencies as well as to extract and validate the associated device compact model, and thus enabling the design of sub-millimeter-wave integrated circuits. Some previous works have already demonstrated InP DHBT characterization beyond 300 GHz [4], [5] using less conventional methods such as on-wafer calibration. With the emergence of 220 GHz broadband vector network analyzer (VNA) [6], it is now being considered feasible to fully characterize a wafer up to 220 GHz.…”