Structure and electrical properties of screen printed contacts on silicon solar cells

Purpose: The aim of the paper was to apply a conventional method “screen printing” using micrometric pastes to improve the quality of forming front side metallization of monocrystalline solar cells. Design/methodology/approach: The topography of co-fired in the infrared belt furnace front contacts were investigated using confocal laser scanning microscope and scanning electron microscope with an energy dispersive X-ray (EDS) spectrometer for microchemical analysis. There were researched both surface topography and cross section of front contacts using SEM microscope. Phase composition analyses of chosen front contacts were done using the XRD method. Front contacts were formed on the surface with different morphology of the solar cells: textured with coated antireflection layer, textured without coated antireflection layer, non-textured with coated antireflection layer, non-textured without coated antireflection layer. The medium size of the pyramids was measured using the atomic force microscope (AFM). Resistance of front electrodes was investigated using Transmission Line Model (TLM). Findings: The high of deposited front metallization has an influence on value obtained from the contact resistance. This high of silver contact depends on: a paste composition, obtained structure after fired into a infrared belt furnace, the quantity and type of creating connections material molecules between themselves and with a silicon substrate. Research limitations/implications: The contact resistance of the screen-printed front metallization depends not only on the paste composition and firing conditions, but is also strongly influenced by the surface morphology of the silicon substrate. Originality/value: This paper investigates the front contact formation using silver pastes about different composition on silicon solar cells in order to decrease contact resistance and increase efficiency in this way.