“…There have been several previous studies of the electrodeposition of selenium films on different substrate surfaces [2,[4][5][6][7][8][9][10][11][12][13]. Those studies mainly focused on either the reduction pathway for Se(IV) [5,6,8,9,11], surface structures of Se atom layers [7,13], characterization of Se films [1,12] or the analysis of a trace amount of Se [9]. The investigation on initial stage of Se electrodeposition, including the nucleus formation and its growth mechanism, has not been reported.…”