Browsing by Author "Mohammed, Mazharuddin"
Now showing 1 - 1 of 1
- Results Per Page
- Sort Options
Item Phonon-Assisted Tunneling in Direct-Bandgap Semiconductors(Amer Inst Physics, 2019-01-02) Mohammed, Mazharuddin; Verhulst, Anne S.; Verreck, Devin; Van de Put, Maarten L.; Magnus, Wim; Soree, Bart; Groeseneken, Guido; 0000-0001-9179-6443 (Van de Put, ML); Van de Put, Maarten L.In tunnel field-effect transistors, trap-assisted tunneling (TAT) is one of the probable causes for degraded subthreshold swing. The accurate quantum-mechanical (QM) assessment of TAT currents also requires a QM treatment of phonon-assisted tunneling (PAT) currents. Therefore, we present a multi-band PAT current formalism within the framework of the quantum transmitting boundary method. An envelope function approximation is used to construct the electron-phonon coupling terms corresponding to local Frohlich-based phonon-assisted inter-band tunneling in direct-bandgap III-V semiconductors. The PAT current density is studied in up to 100 nm long and 20 nm wide p-n diodes with the 2- and 15-band material description of our formalism. We observe an inefficient electron-phonon coupling across the tunneling junction. We further demonstrate the dependence of PAT currents on the device length, for our non-self-consistent formalism which neglects changes in the electron distribution function caused by the electron-phonon coupling. Finally, we discuss the differences in doping dependence between direct band-to-band tunneling and PAT current. Published under license by AIP Publishing.