recombination{}¶
This section specifies the coefficients related to recombination processes. These are used when the current equation is solved. In nextnano++, the following recombination processes are included:
Example¶
binary_zb {
name = Si # material name, e.g. Si, GaAs, InP, ...
...
recombination{
# ShockleyReadHall recombination
SRH{ tau_n = 1.0e9 # [s] zero doping scattering time for electrons
nref_n = 1.0e19 # [cm^3] reference doping concentration for electrons
tau_p = 1.0e9 # [s] zero doping scattering time for holes
nref_p = 1.0e18 # [cm^3] reference doping concentration for holes
}
# Auger recombination
Auger{ c_n = 2.8e31 # [cm^6/s]
c_p = 9.9e31 # [cm^6/s]
}
# direct recombination
radiative{ c = = 2.0e10 } # [cm^3/s]
# 2.0e10 for GaAs, 0 for Si (indirect semiconductor)
}
}
ShockleyReadHall (SRH) recombination¶
# ShockleyReadHall recombination
SRH{ tau_n = 1.0e9 # [s] zero doping scattering time for electrons
nref_n = 1.0e19 # [cm^3] reference doping concentration for electrons
tau_p = 1.0e9 # [s] zero doping scattering time for holes
nref_p = 1.0e18 # [cm^3] reference doping concentration for holes
}
SRH model models the generation/recombination process that is assisted by impurities. The recombination/generation rates depend on the deviation of the carrier concentration from the equilibrium value and the scattering rates depend on the doping concentration.
\(\tau_{n0}\) 

\(N_{n,ref}\) 

\(\tau_{p0}\) 

\(N_{p,ref}\) 

Auger recombination¶
# Auger recombination
Auger{ c_n = 2.8e31 # [cm^6/s]
c_p = 9.9e31 # [cm^6/s]
}
More imformation on physics: Auger recombination processes in semiconductor heterostructures.
For devices with an extremely high carrier concentration the Auger process is the dominant recombination channel. The process involves three particles and therefore scales with the third power of the carrier densities.
The phononassisted Auger recombination rate, which plays an important role especially at high carrier injection, respectively high doping levels, will be modeled in the program by the following equation:
\(C_n\) 

\(C_p\) 

Radiative recombination¶
# direct recombination
radiative{ c = = 2.0e10 } # [cm^3/s]
# 2.0e10 for GaAs, 0 for Si (indirect semiconductor)
The simplest process for the generation and recombination of electronhole pairs is the direct process via the emission or absorption of a photon (radiative recombination). This is important for light emitting devices.
\(C\) 
