부산대학교 도서관

The formation and phase evolution of Cu-S based compounds in kesteriteCu2ZnSnS4 (CZTS) absorbing thin films is a critical factor affecting theperformance of these materials in thin film solar cells (TFSCs). However,to the best of our knowledge, few studies have investigated the segregationof Cu-S based compounds in kesterite thin films during the sulfurizationprocess. In this study, stacked Cu/SnS2/ZnS precursor thin films wereannealed to systematically study the segregation and phase evolution ofCu-S based compounds in kesterite thin films subjected to functionalsulfurization times at 550°C. The stacked precursor thin films appeared tobe fully transformed to the pure kesterite phase when the sulfurizationtimes are over 30 min. when analyzed using X-ray diffraction and Ramanspectroscopy. However, transmission electron microscopy (TEM)characterization revealed that Cu-S based compounds segregated in thekesterite CZTS thin films annealed for 120 min. at 550°C. Based on theexperimental results obtained for functional sulfurization times, amechanism for Cu-S based compounds segregation and the phaseevolution process is proposed.