MODELLING AND SIMULATION STUDY OF VISIBLE EMISSION TRANSMISSIVITY OF SILICON RELATED TO SINGLE AND MULTILAYER ANTIREFLECTION COATINGS

In this study, the effect of single and multilayer thin film coatings at the central wavelength 720 nm on the transmissivity of silicon as active medium has been investigated. A model, based on the Transfer Matrix Method (TMM) of multilayer is used to evaluate the transmittance of Si as active medium (emitter) at 720–750 nm when Ge, SiO2 and Si are used as single and multilayer thin film coatings. The results of this simulation study lead to the following conclusions: the transmissivity of ~ 720–750 nm emission of silicon is affected significantly by the single and multilayer thin film coatings of Ge, SiO2 and Si/SiO2/air and Si/Ge/Si/SiO2/air show high transmissivity of 92% and 100% at 720 nm respectively. Uncoated Si (active medium) surface shows low transmissivity of 66%. The width of the high-transmittance region of Si/Ge/Si/SiO2/air is less than Si/SiO2/air at 720 nm.