  Through advanced quantum mechanical simulations combining electron and phonon
transport from first-principles self-heating effects are investigated in n-type
transistors with a single-layer MoS2, WS2, and black phosphorus as channel
materials. The selected 2-D crystals all exhibit different phonon-limited
mobility values, as well as electron and phonon properties, which has a direct
influence on the increase of their lattice temperature and on the power
dissipated inside their channel as a function of the applied gate voltage and
electrical current magnitude. This computational study reveals (i) that
self-heating plays a much more important role in 2-D materials than in Si
nanowires, (ii) that it could severely limit the performance of 2-D devices at
high current densities, and (iii) that black phosphorus appears less sensitive
to this phenomenon than transition metal dichalcogenides.
