A Single- Element VNA Electronic Calibration in CMOS

Abstract

This paper presents a direct on-wafer VNA calibration algorithm for millimeter-wave frequency device characterization using a single calibration standard fabricated in 65-nm CMOS technology. The standard consists of three NMOS transistors configured in a $\pi$ -network whose impedance can be modulated independently and electronically through the corresponding gate bias. To solve for the seven error terms in the 2-port error model, the algorithm exploits both the reciprocity of the network and a quasi-short-open-Ioad (QSOL) 1-port calibration technique. The algorithm is validated against on-wafer TRL with experimental results from 1 to 67 GHz.