Vol. 5, Issue 2, Part A (2023)

The present work analyzes the important function of the emitter layer in heterojunction with intrinsic thin layer solar cells, highlighting its involvement in electric field generation and the separation and transport of charge carriers. The AFORS-HET modeling tool is employed to analyze various materials, including amorphous silicon (a-Si:H), nanocrystalline silicon (nc-Si:H), microcrystalline silicon (μc-Si:H), and amorphous silicon carbide (a-SiC:H), with the aim of optimizing their thickness, doping concentration, bandgap, and electrical properties to improve solar cell performance. The simulations indicate that the open circuit voltage (V_oc) and short circuit current density (J_sc) are enhanced by various emitter layers, with nc-Si:H exhibiting the most substantial improvements owing to its wide bandgap, diminished contact resistivity at the nc-Si:H-Transparent Conducting Oxide (TCO) interface, lower defect density, improved passivation, and superior carrier collection. The research indicates that the fill factor (FF) and efficiency of solar cells improve when the emitter layer shifts from a-Si:H to a-SiC:H, μc-Si:H, and nc-Si:H, with efficiencies increasing from 19.46% to 22.2%. The results emphasize the necessity of choosing suitable emitter materials to attain maximum solar cell efficiency, showcasing the benefits of a-SiC:H, μc-Si:H, and nc-Si:H for conductivity, light transmission, and charge carrier mobility. The study indicates that to achieve optimal efficiency in heterojunction solar cells, emitter layers must have a broad bandgap, high conductivity, and minimal defect density.