ADVANCED METALLISATION METHODS FOR MONOCRYSTALLINE SILICON WAFER SOLAR CELLS

Abstract

This thesis focuses on the application and characterisation of screen printing and electrochemical (plating) technologies for silicon wafer solar cell metallisation. The metallisation technologies are applied to silicon homojunction and amorphous silicon/crystalline silicon heterojunction cells fabricated on monocrystalline silicon wafers. Since metallisation significantly influences the cells? fill factor, a fill factor loss analysis method is developed. Then, the influence of an alkaline surface texture on silicon homojunction cell metallisation is evaluated using an advanced statistical approach. Thickening of printed silver electrodes by silver light-induced plating is shown to significantly lower the contact resistance to phosphorus-doped silicon regions. Next, the unique metallisation requirements of heterojunction cells are identified and metallisation methods are tailored for such cells. Screen printing followed by moderate-temperature annealing is studied for heterojunction cell metallisation. A detailed investigation is also conducted on transparent conductive oxide layer masking followed by electroplating (nickel-copper) for heterojunction cells.