front_materials = []
back_materials = []
# whether pyramids are upright or inverted is relative to front incidence.
# so if the same etch is applied to both sides of a slab of silicon, one surface
# will have 'upright' pyramids and the other side will have 'not upright' (inverted)
# pyramids in the model
surf = regular_pyramids(elevation_angle=55, size=5, upright=True)
front_surf = Interface('RT_TMM',
texture=surf,
layers=[Layer(si('0.1nm'), Air)],
name='pyramids' + str(options['n_rays']))
back_surf = Interface('Lambertian', layers=[], name='lambertian')
bulk_Si = BulkLayer(201.8e-6, Si, name='Si_bulk') # bulk thickness in m
SC = Structure([front_surf, bulk_Si, back_surf],
incidence=Air,
transmission=Air)
process_structure(SC, options)
results = calculate_RAT(SC, options)
RAT = results[0]
results_per_pass = results[1]
# load OPTOS/measured data
sim = np.loadtxt('data/optos_fig7_sim.csv', delimiter=',')
# so if the same etch is applied to both sides of a slab of silicon, one surface
# will have 'upright' pyramids and the other side will have 'not upright' (inverted)
# pyramids in the model
## TMM, matrix framework
front_surf = Interface('TMM',
layers=front_materials,
name='GaInP_GaAs_SiGeSn_TMM',
coherent=True)
back_surf = Interface('TMM',
layers=back_materials,
name='SiN_Air_TMM',
coherent=True)
bulk_Si = BulkLayer(bulkthick, Ge, name='Ge_bulk') # bulk thickness in m
SC = Structure([front_surf, bulk_Si, back_surf],
incidence=Air,
transmission=Air)
process_structure(SC, options)
results_TMM_Matrix = calculate_RAT(SC, options)
results_per_pass = results_TMM_Matrix[1]
R_per_pass = np.sum(results_per_pass['r'][0], 2)
R_0 = R_per_pass[0]
R_escape = np.sum(R_per_pass[1:, :], 0)
# only select absorbing layers, sum over passes