def change_doping(self, Na):
self.Na=Na
self.diode = Device(mesh=self.mesh,
temperature=300, # K
material=self.zno_cu2o,
dopants=(Donor(concentration=self.Nd * self.ntype, # m**-3"
ionizationEnergy=-1.), # eV
Acceptor(concentration=Na * self.ptype, # m**-3
ionizationEnergy=-1.)), # eV
traps=(ShockleyReadHallTrap(recombinationLevel=0, # eV
electronMinimumLifetime=3e-11, # s
holeMinimumLifetime=3e-11),), # s
contacts=(self.pContact, self.nContact))
self.diode.contacts[1].bias.value = 0. # V
self.diode.contacts[0].bias.value = 0. # V
def __init__(self, Na, Nd):
n_thickness = 2e-6 # m
p_thickness = 4e-6 # m
grid_resolution = 2.0e-8 # m
self.n_thickness = n_thickness
self.p_thickness = p_thickness
self.grid_resolution = grid_resolution
# Creates series of spacings (dx) that decrease rapidly according to a power law.
compression_factor = 0.8
compression_count = 60
compressed_dx = grid_resolution * compression_factor**numerix.arange(compression_count)
compressed_length = compressed_dx.sum()
compressed_dx = list(compressed_dx)
# Creates the spacings for the n-side of the pn junction. Starts dense (short dx) near the contact, gets longer in the middle of the n region, then gets shorter again at the junction. The compressed_dx spacing is used to describe the spacings (dx) as you get closer to the interesting regions, which are the contacts and the junction.
n_uncompressed_thickness = n_thickness - 2 * compressed_length
n_dx = n_uncompressed_thickness / round(n_uncompressed_thickness / grid_resolution)
n_dx = compressed_dx[::-1] + [n_dx] * int(n_uncompressed_thickness / n_dx) + compressed_dx
# Same thing is done for the p side.
p_uncompressed_thickness = p_thickness - 2 * compressed_length
p_dx = p_uncompressed_thickness / round(p_uncompressed_thickness / grid_resolution)
p_dx = compressed_dx[::-1] + [p_dx] * int(p_uncompressed_thickness / p_dx + 0.5) + compressed_dx
mesh = Grid1D(dx=n_dx + p_dx)
x = mesh.cellCenters[0]
# To view the node density:
#from pylab import plot
#plot (x, ones(len(x)), 'o')
ntype = x < n_thickness # print ntype to see True and False values
ptype = x >= n_thickness
vacuum = ~(ntype | ptype)
# Assigning material properties to each Cell
zno_cu2o = (ZnO() * ntype + Cu2O() * ptype + Vacuum() * vacuum)
nFaces = mesh.facesLeft
pFaces = mesh.facesRight
illuminatedFaces =mesh.facesLeft
self.illuminatedFaces = illuminatedFaces
nContact = OhmicContact(faces=nFaces)
pContact = OhmicContact(faces=pFaces)
# Nd = 1e24 #m**-3
# Na = 1e21 #m**-3
self.Na=Na
self.Nd=Nd
self.diode = Device(mesh=mesh,
temperature=300, # K
material=zno_cu2o,
dopants=(Donor(concentration=Nd * ntype, # m**-3"
ionizationEnergy=-1.), # eV
Acceptor(concentration=Na * ptype, # m**-3
ionizationEnergy=-1.)), # eV
traps=(ShockleyReadHallTrap(recombinationLevel=0, # eV
electronMinimumLifetime=3e-11, # s
holeMinimumLifetime=3e-11),), # s
contacts=(pContact, nContact))
self.diode.contacts[1].bias.value = 0. # V
self.diode.contacts[0].bias.value = 0. # V
class EqeDoping(object):
def __init__(self, Na, Nd):
n_thickness = 2e-6 # m
p_thickness = 4e-6 # m
grid_resolution = 2.0e-8 # m
self.n_thickness = n_thickness
self.p_thickness = p_thickness
self.grid_resolution = grid_resolution
# Creates series of spacings (dx) that decrease rapidly according to a power law.
compression_factor = 0.8
compression_count = 60
compressed_dx = grid_resolution * compression_factor**numerix.arange(compression_count)
compressed_length = compressed_dx.sum()
compressed_dx = list(compressed_dx)
# Creates the spacings for the n-side of the pn junction. Starts dense (short dx) near the contact, gets longer in the middle of the n region, then gets shorter again at the junction. The compressed_dx spacing is used to describe the spacings (dx) as you get closer to the interesting regions, which are the contacts and the junction.
n_uncompressed_thickness = n_thickness - 2 * compressed_length
n_dx = n_uncompressed_thickness / round(n_uncompressed_thickness / grid_resolution)
n_dx = compressed_dx[::-1] + [n_dx] * int(n_uncompressed_thickness / n_dx) + compressed_dx
# Same thing is done for the p side.
p_uncompressed_thickness = p_thickness - 2 * compressed_length
p_dx = p_uncompressed_thickness / round(p_uncompressed_thickness / grid_resolution)
p_dx = compressed_dx[::-1] + [p_dx] * int(p_uncompressed_thickness / p_dx + 0.5) + compressed_dx
mesh = Grid1D(dx=n_dx + p_dx)
x = mesh.cellCenters[0]
# To view the node density:
#from pylab import plot
#plot (x, ones(len(x)), 'o')
ntype = x < n_thickness # print ntype to see True and False values
ptype = x >= n_thickness
vacuum = ~(ntype | ptype)
# Assigning material properties to each Cell
zno_cu2o = (ZnO() * ntype + Cu2O() * ptype + Vacuum() * vacuum)
nFaces = mesh.facesLeft
pFaces = mesh.facesRight
illuminatedFaces =mesh.facesLeft
self.illuminatedFaces = illuminatedFaces
nContact = OhmicContact(faces=nFaces)
pContact = OhmicContact(faces=pFaces)
# Nd = 1e24 #m**-3
# Na = 1e21 #m**-3
self.Na=Na
self.Nd=Nd
self.diode = Device(mesh=mesh,
temperature=300, # K
material=zno_cu2o,
dopants=(Donor(concentration=Nd * ntype, # m**-3"
ionizationEnergy=-1.), # eV
Acceptor(concentration=Na * ptype, # m**-3
ionizationEnergy=-1.)), # eV
traps=(ShockleyReadHallTrap(recombinationLevel=0, # eV
electronMinimumLifetime=3e-11, # s
holeMinimumLifetime=3e-11),), # s
contacts=(pContact, nContact))
self.diode.contacts[1].bias.value = 0. # V
self.diode.contacts[0].bias.value = 0. # V
def solve_dark(self, view=False, save = False):
# solve in dark and then illuminate
self.diode.solve(solver=None, sweeps=10, outer_tol=1e4)
if view == True:
self.viewer = Viewer(vars=(self.diode.Ec, self.diode.Efn, self.diode.Efp, self.diode.Ev))
self.npViewer = Viewer(vars=(self.diode.n, self.diode.p), log=True)
if save == True:
self.diode.save('dark{Na}.band'.format(Na=self.Na))
def solve_light(self, view=False, save = False):
self.light = AM1_5(orientation=[[1]],
faces=self.illuminatedFaces)
# sample the light source from 300 nm to 1 um at 10 nm intervals
self.diode.illuminate(self.light(wavelength=numerix.arange(300e-9, 1000e-9, 1e-9))) # m
self.diode.solve(solver=None, sweeps=10, outer_tol=1e4)
if save == True:
self.diode.save('light{Na}.band'.format(Na=self.Na))
if view == True:
self.viewer = Viewer(vars=(self.diode.Ec, self.diode.Efn, self.diode.Efp, self.diode.Ev))
self.npViewer = Viewer(vars=(self.diode.n, self.diode.p), log=True)
def solve_eqe(self, view=False, save = False):
self.eqe_spectrum = self.diode.EQE(self.light, numerix.arange(320e-9,700e-9, 1e-9), path=None, adapt=True)
if view ==True:
import pylab
pylab.figure()
wavelength, eqe = zip(*self.eqe_spectrum)
pylab.plot(wavelength,eqe)
if save == True:
self.save_eqe('eqe{Na}.eqe'.format(Na = self.Na))
def save_eqe(self,fname):
header = """
ZnO _doping:{Nd}
Cu2O doping: {Na}
ZnO thickness: {n_thick}
Cu2O thickness: {p_thick}
grid resolution: {grid_res}
""".format(Na=self.Na, Nd=self.Nd, n_thick = self.n_thickness, p_thick = self.p_thickness, grid_res = self.grid_resolution)
with open(fname, 'wb') as f:
f.write(header)
for i in self.eqe_spectrum:
wavelength_point, eqe_point = i
f.write('{wavelength}\t{eqe}\n'.format(wavelength=wavelength_point, eqe=eqe_point))
nContact = OhmicContact(faces=nFaces)
pContact = OhmicContact(faces=pFaces)
##graded doping
x_dummy = x.value*(x.value>=n_thickness)
y_dummy = (1e22*(x_dummy-n_thickness)/(p_thickness-n_thickness) + 1e17 )*(x.value>=n_thickness) #linear
y_dummy =1e21*abs(numerix.sin((x_dummy-n_thickness)*2e6))# abs(sin(x))
diode = Device(mesh=mesh,
temperature=300, # K
material=cdse_cdte,
dopants=(Donor(concentration=1e23 * ntype, # m**-3"
ionizationEnergy=-1.), # eV
Acceptor(concentration=y_dummy * ptype, # m**-3
ionizationEnergy=-1.)), # eV
traps=(ShockleyReadHallTrap(recombinationLevel=0, # eV
electronMinimumLifetime=3e-11, # s
holeMinimumLifetime=3e-11),), # s
contacts=(pContact, nContact))
diode.contacts[1].bias.value = 0. # V
diode.contacts[0].bias.value = 0. # V
# solve in dark and then illuminate
diode.solve(solver=None, sweeps=10, outer_tol=1e4)
light = AM1_5(orientation=[[1]],
faces=illuminatedFaces)
