% Constants and parameters
q = 1.602e-19; % elementary charge
k = 1.38e-23; % Boltzmann constant
eps0 = 8.85e-12; % vacuum permittivity
epsr = 11.7; % relative permittivity of silicon
Na = 1e17; % doping concentration (p-type)
L = 1e-6; % length of the semiconductor
mu_e = 1000*1e-4; % electron mobility
mu_h = 1000*1e-4; % hole mobility
D_e = k*300*mu_e/q; % electron diffusion coefficient
D_h = k*300*mu_h/q; % hole diffusion coefficient
T = 300; % temperature
V = 0.1; % applied voltage
% Spatial and time parameters
nx = 100; % number of spatial grid points
dx = L/nx; % spatial step
dt = 1e-9; % time step
nt = 100; % number of time steps
% Initialize carrier densities and electric potential
n = zeros(nx, 1); % electron density
p = zeros(nx, 1); % hole density
phi = zeros(nx, 1); % electric potential
phi(1) = V; % boundary condition at x=0
% Simulation loop
for t = 1:nt
% Calculate electric field
E = -(phi(2:end) – phi(1:end-1))/dx;

% Calculate electron and hole densities
Jn = q*D_e*(n(3:end) – n(2:end-1))/dx – q*mu_e*E.*n(2:end-1);
Jp = q*D_h*(p(3:end) – p(2:end-1))/dx + q*mu_h*E.*p(2:end-1);

% Update carrier densities
n(2:end-1) = n(2:end-1) + dt*Na./(1+exp((phi(2:end-1)-V/2)/(k*T))) – dt*Jn;
p(2:end-1) = p(2:end-1) + dt*Na./(1+exp((V/2-phi(2:end-1))/(k*T))) – dt*Jp;

% Update electric potential
rho = q*(Na – n – p); % charge density
phi(2:end-1) = phi(2:end-1) + dt*1/(epsr*eps0)*rho(2:end-1);
end% Constants and parameters
q = 1.602e-19; % elementary charge
k = 1.38e-23; % Boltzmann constant
eps0 = 8.85e-12; % vacuum permittivity
epsr = 11.7; % relative permittivity of silicon
Na = 1e17; % doping concentration (p-type)
L = 1e-6; % length of the semiconductor
mu_e = 1000*1e-4; % electron mobility
mu_h = 1000*1e-4; % hole mobility
D_e = k*300*mu_e/q; % electron diffusion coefficient
D_h = k*300*mu_h/q; % hole diffusion coefficient
T = 300; % temperature
V = 0.1; % applied voltage
% Spatial and time parameters
nx = 100; % number of spatial grid points
dx = L/nx; % spatial step
dt = 1e-9; % time step
nt = 100; % number of time steps
% Initialize carrier densities and electric potential
n = zeros(nx, 1); % electron density
p = zeros(nx, 1); % hole density
phi = zeros(nx, 1); % electric potential
phi(1) = V; % boundary condition at x=0
% Simulation loop
for t = 1:nt
% Calculate electric field
E = -(phi(2:end) – phi(1:end-1))/dx;

% Calculate electron and hole densities
Jn = q*D_e*(n(3:end) – n(2:end-1))/dx – q*mu_e*E.*n(2:end-1);
Jp = q*D_h*(p(3:end) – p(2:end-1))/dx + q*mu_h*E.*p(2:end-1);

% Update carrier densities
n(2:end-1) = n(2:end-1) + dt*Na./(1+exp((phi(2:end-1)-V/2)/(k*T))) – dt*Jn;
p(2:end-1) = p(2:end-1) + dt*Na./(1+exp((V/2-phi(2:end-1))/(k*T))) – dt*Jp;

% Update electric potential
rho = q*(Na – n – p); % charge density
phi(2:end-1) = phi(2:end-1) + dt*1/(epsr*eps0)*rho(2:end-1);
end % Constants and parameters
q = 1.602e-19; % elementary charge
k = 1.38e-23; % Boltzmann constant
eps0 = 8.85e-12; % vacuum permittivity
epsr = 11.7; % relative permittivity of silicon
Na = 1e17; % doping concentration (p-type)
L = 1e-6; % length of the semiconductor
mu_e = 1000*1e-4; % electron mobility
mu_h = 1000*1e-4; % hole mobility
D_e = k*300*mu_e/q; % electron diffusion coefficient
D_h = k*300*mu_h/q; % hole diffusion coefficient
T = 300; % temperature
V = 0.1; % applied voltage
% Spatial and time parameters
nx = 100; % number of spatial grid points
dx = L/nx; % spatial step
dt = 1e-9; % time step
nt = 100; % number of time steps
% Initialize carrier densities and electric potential
n = zeros(nx, 1); % electron density
p = zeros(nx, 1); % hole density
phi = zeros(nx, 1); % electric potential
phi(1) = V; % boundary condition at x=0
% Simulation loop
for t = 1:nt
% Calculate electric field
E = -(phi(2:end) – phi(1:end-1))/dx;

% Calculate electron and hole densities
Jn = q*D_e*(n(3:end) – n(2:end-1))/dx – q*mu_e*E.*n(2:end-1);
Jp = q*D_h*(p(3:end) – p(2:end-1))/dx + q*mu_h*E.*p(2:end-1);

% Update carrier densities
n(2:end-1) = n(2:end-1) + dt*Na./(1+exp((phi(2:end-1)-V/2)/(k*T))) – dt*Jn;
p(2:end-1) = p(2:end-1) + dt*Na./(1+exp((V/2-phi(2:end-1))/(k*T))) – dt*Jp;

% Update electric potential
rho = q*(Na – n – p); % charge density
phi(2:end-1) = phi(2:end-1) + dt*1/(epsr*eps0)*rho(2:end-1);
end fdtd, drift diffusion model MATLAB Answers — New Questions

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