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  output-current-data

 

 

 
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Output-current-data

The output of current, Fermi levels, mobilities and I-V characteristics is controlled by this keyword.

!-------------------------------------------------------------------!
$output-current-data                                       optional !
 destination-directory                character            required !
 current                              character            optional !
 recombination                        character            optional !
 fermi-levels                         character            optional !
 mobility-out                         character            optional !
 IV-curve-out                         character            optional !
$end_output-current-data                                   optional !
!-------------------------------------------------------------------!

Syntax:

destination-directory = my-directory/
                 e.g. = current/

Name of directory to which the files should be written. Must exist and directory name has to include the slash (\ for DOS and / for UNIX)

 

current = yes / no

Flag whether to put out current.

 

recombination  = yes / no

Flag whether to put out the generation and recombination rates (net recombination, SRH = Shockley-Read-Hall, Auger, direct = radiative, total).
The units are [1018 cm-3s-1].

 

fermi-levels = yes / no 

Flag whether to put out the Fermi levels

 

mobility-out = yes / no 

Flag whether to put out the mobility, diffusion constant, drift velocity, and also the conductivity.

 

IV-curve-out = yes[A/m^2]  ! 1D simulation: Output current density in units of [A/m^2].
           
 = yes[A/cm^2] !
1D simulation: Output current density in units of [A/cm^2].
           
 = yes[A/m]    !
2D simulation: Output current density in units of [A/m].
           
 = yes[A/cm]   !
2D simulation: Output current density in units of [A/cm].
           
 = yes[A]      !
3D simulation: Output current density in units of [A].
           
 = yes         !
Output current density in units of [A/m^2] (1D), [A/m] (2D), [A] (3D) (default units)
           
 = no          !
do not output I-V curve

Flag whether to put out the I-V characteristics (i.e. current density as a function of applied voltage).
For ballistic calculations using the CBR method, for each Schrödinger equation the ballistic current is written out. The last column is the sum of ballistic currents of all Schrödinger equations.

 

Output

Filenames and structure


 

Current:

1D output

filename:

currentD_ind000.dat
  _ind000 number of voltage step corresponding to this output file (only if voltage sweep is turned on)

structure:                          

distance: el: hl: total:
0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00
Position in space [nm] Electron current [A/m2] Hole current [A/m2] Total current Itot=Iel+Ihl [A/m2]

 

 

2D output

current_el2D_x_ind001.fld   / *.coord   / *.dat
...

- el/hl  is for electron/hole current output
- x/y    is for x- or y-component of two-dimensional current vector in units of [A/cm2]
- ind001 is for 1st voltage sweep index

 

3D output

current_hl3D_y_ind004.fld   / *.coord   / *.dat
...


- el/hl  is for electron/hole current output
- x/y/is for x-, y- or z-component of three-dimensional current vector in units of [A/cm2]
- ind004 is for 4th voltage sweep index

 


 

Fermi levels:

quasi-Fermi levels of electrons and holes [eV]

filename:

fermi1D_el_ind000.dat
    _el
  _hl
  indicates if Fermi level for electrons (_el) or holes (_hl) is contained
    _ind000 number of voltage step corresponding to this output file (only if voltage sweep is turned on)

structure:                          

distance: fermi_el:
0.000000E+00 0.000000E+00
Position in space [nm] Fermi level [eV]

 


 

Drift velocity:

drift velocity of electrons and holes [cm/s]

filename:

drift_velocity_ind004.dat
  _ind004 number of voltage step corresponding to this output file (only if voltage sweep is turned on)

structure:                          

position[nm] vd_n[cm/s] vd_p[cm/s]
0.000000E+00 0.000000E+00 0.000000E+00
Position in space [nm] Electron drift velocity [cm/s] Hole drift velocity [cm/s]

 


 

Mobility:

mobility of electrons and holes in units of [cm2/Vs] and diffusion constants in units of [m^2/s]

1D output

filename:

mobility1D_ind001.dat
  _ind000 number of voltage step corresponding to this output file (only if voltage sweep is turned on)

structure: 

position[nm] mu_n[cm^2/Vs] mu_p[cm^2/Vs] D_n[m^2/s] D_p[m^2/s]
0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00 0.000000E+00
Position in space [nm] Electron mobility [cm²/Vs] Hole mobility [cm²/Vs] Electron diffusion constant [m²/s] Hole diffusion constant [m²/s]

 

2D output

mobility_el2D_x_ind001.fld   / *.coord   / *.dat
...

- el/hl  is for electron/hole mobility output
- x/y    is for x- or y-component of two-dimensional mobility in units of [cm2/Vs]
- ind001 is for 1st voltage sweep index

 

3D output

mobility_hl3D_y_ind004.fld   / *.coord   / *.dat
...


- el/hl  is for electron/hole mobility output
- x/y/is for x-, y- or z-component of three-dimensional mobility in units of [cm2/Vs]
- ind004 is for 4th voltage sweep index

 


 

Conductivity

Total conductivity sigma, and conductivity of electrons sigmael and holes sigmahl in units of [Ohm-1m-1]

sigma = sigmael + sigmahl = (µel n + µh p) e

conductivity1D_ind001.dat

  position[nm]   sigma[Ohm^-1m^-1]   sigma_n[Ohm^-1m^-1]   sigma_p[Ohm^-1m^-1]

 


 

Recombination

The recombination rate R is contained in this file: recombination1D.dat

The recombination rate is divided in two parts, one for electrons (rec_el) and one for holes (rec_hl) because of the following reason:
If one regards generation/recombination processes together with quantum mechanical wave functions it is possible that the electron is located elsewhere than the hole and therefore the spatial distribution of the recombination/generation rates for electrons and holes is different (still under examination!).

Depending on which recombination models are used, the recombination output is the sum of direct (radiative), Auger and Shockley-Read-Hall recombination, and generation, so it is a net recombination.
(If it is negative, generation dominates.)

The recombination file contains the following columns:
 position[nm]   rec_el[10^18/(cm^3s)]   rec_hl[10^18/(cm^3s)]    SRH[10^18/(cm^3s)]  Auger[10^18/(cm^3s)]  direct[10^18/(cm^3s)]  total[10^18/(cm^3s)]  R-G[10^18/(cm^3s)]

total = SRH + Auger + direct
R-G   =
total recombination rate - generation rate (a negative value means net generation)

A separate file will be printed out that contains the generation rate G only: generation1D.dat
 position[nm]   G[10^18/(cm^3s)]

 


 

I-V characteristics:

The current-voltage characteristics (I-V characteristics) are contained in this file.

Filename:

IV_characteristics1D.dat (1D simulation)
IV_characteristics2D.dat
(2D simulation)
IV_characteristics3D.dat
(3D simulation)

Structure: 

VOLT_CL001 VOLT_CL002  CUR_EL001 CUR_EL002 CUR_HL001 CUR_HL002 CUR_TOT001 CUR_TOT002
Voltage
cluster 1
[V]
Voltage
cluster 2
[V]
electron current
cluster  1
[A/m2]
electron current
cluster 2
[A/m2]
hole current
cluster 1
[A/m2]
hole current
cluster 2
[A/m2]
Total current
cluster 1
[A/m2]
Total current
cluster 2
[A/m2]

Units:
- 1D: [A/m²]
- 2D: [A/m]
- 3D: [A]