A comparison of chemical bath deposition and spray pyrolysed Cd-free buffer layers in CuInS2 solar cells by TEM cross-section analysis

With the aim of developing a Cd-free chalcopyrite solar cell, In(OH)xSy and ZnO buffer layers have been deposited by chemical bath deposition and the more novel approach of ultrasonic spray pyrolysis. Crosssections of the completed solar cell devices were cut using a focused ion beam system and inspected using transmission electron microscopy. The TEM images of the buffer layers, prepared using the two deposition techniques are compared and correlated to the illuminated current-voltage curves of the solar cells.