Substanciating GTS' leadership in TCAD for nano-scaled devices, CTO Zlatan Stanojević explains the concept behind GTS' comprehensive framework for predictive TCAD at the nano-scale.
The combined approach, involving the sub-band Boltzmann transport equation, a drift-diffusion-based simulator as well as a Poisson solver, is computationally robust and adaptive. The SISPAD talk elaborates on underlying numerics and the validity of the approach.
After three iterations the potential and Fermi energy are already close to the converged result.
By setting the number of subbands equal to the number of subbands needed to resolve the distribution function at the top of the barrier (ToB), the ballistic velocity profile is reproduced well. The unprimed valley in a ⟨110⟩-oriented channel is highly non-parabolic; while particle momentum increases during acceleration, the group velocity does not increase monotonically, hence no velocity overshoot can be observed for the unprimed valley.
Calculating transport with a fixed number of subbands will either yield too low average velocity due to either having to little populated states, or a too large velocity overshoot because of reduced scattering due to a lack of final states. Setting the number of subbands equal to the number at ToB still overestimates velocity overshoot; the ToB-limited velocity profile begins to diverge from the unlimited one after ToB.
|Tue, Sept. 6: Paper Session 04.1: Boltzmann Transport I (Albrecht-Durer-Saal)|
Phase-Space Solution of the Subband Boltzmann
The International Conference on Simulation of Semiconductor Processes and Devices (SISPAD) 2016 takes place in Nürnberg (Nuremberg), Germany during September 6-8, 2016.
For details, program, and registration, please visit the SISPAD 2016 web site.
Dedicated to scientific research, GTS is happy to support SISPAD 2016 as a silver sponsor.