Screen Printing Technology Improvement Of Crystalline Silicon Solar Cells

Ther conversion efficiency of the solar cell has stagnated at15%~17%，in order toimprove the efficiency, from2010, people started to study the double screen printing methodto increase the aspect ratio, reduce the shadow area, to improve the conversion efficiency ofsolar cells, but the research is still at the exploratory stage.Firstly, this paper established the theoretical models of fill factor, including factors ofscreen printing expand as well as overprint expand, by introduction of screen printing expandfactor. And it analysed the change basing on the line widen. Secondly, according to thepropose of Denis Erath and his partner, we implemented comparison experiments betweendouble screen printing with big wire open meshes, and single screen printing with small wireopen meshes.The testing results of the electrical performance shows, the series resistance of theeletrodes diminished according to the influence of line widen, especially the double screenprinting, it also allowed in a fall of40%and20%in the Aspect Ratio, and a fall of19%and22%~23%in fill factor, seperately in single and double printing. Resulting from theforegoing analysis, the line widen can diminish the fill factor, the bigger the widen, thesmaller the fill factor, the experimental results validate the theoretical simulation very well.Meanwhile, the efficiency of double printing finally achieved a0.4%growth comparing tosingle printing.The theoretical models of this paper can be helpful in cell metallization and theprediction the fill factor change caused by line widen, after the procession of paremeters ofselected raw materials and technology of companies, then calculating the growth rate of theconversion efficiency of the silicon solar cell.