Abstract

Numerous research groups are currently developing high-performance InP HBTs with fT and fMAX greater than 400GHz. However, the heavily degenerate doping concentrations used in these devices present new challenges to numerical device simulation. This work focuses on three physical phenomena in InP and In0.53Ga0.47As and their implementation in physics based device simulators. First, the use of the parabolic band approximation yields a constant DOS effective mass, but this results in an erroneously deep Fermi-level under heavily degenerate donor concentrations. An empirical model is presented and shown to have good agreement with previously published simulations and experimental data. Second, bandgap narrowing parameters and a table based model are used as a more generic model for compound semiconductors. Third, calculated parameters to address the Mott transition are used to obtain the proper free-carrier concentrations throughout the HBT. The improper calibration or neglect of these three physical phenomena is shown to alter HBT band profiles at thermal equilibrium by as much as 400meV; the turn-on voltage by approximately 50mV; and the fT dependence on JC by approximately 18%.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.