On-wafer 16-term calibration approach for dual-setup, bias-dependent RF characterization of scaled InP HBTs

Abstract

Abstract In this article, indium phosphide heterojunction bipolar transistors measured at two different measurement setups are characterized by systematic comparison of the 16-term corrected and conventional 8-term multiline Thru-Reflect-Line (mTRL) corrected scattering parameters. The on-wafer calibration standards and down-scaled transistors with emitter widths of left bracket 850 right bracket nm $[850]{nm}$ [ 850 ] n m and left bracket 500 right bracket nm $[500]{nm}$ [ 500 ] n m are measured up to left bracket 67 right bracket GHz $[67]{GHz}$ [ 67 ] G H z and up to left bracket 110 right bracket GHz $[110]{GHz}$ [ 110 ] G H z . A detailed methodology for defining the actual scattering parameters of the calibration standards, which are essential for the successful implementation of on-wafer 16-term calibration, is presented. A direct comparison of Mason’s unilateral power gain determined using a 16-term calibration and a conventional 8-term mTRL calibration demonstrates that the 16-term calibration approach yields a reasonably stable estimate of transistor figures of merit such as maximum oscillation frequency fmax $f_{\mathrm{max}}$ f m a x in a wide range of measurement frequencies, bias conditions, and technology nodes. A statistical analysis of the extracted fmax $f_{\mathrm{max}}$ f m a x