Molecular level pathway to CIS deposition without post treatments

CuInSe₂ (CIS) based thin-film devices could potentially provide high specific power for terrestrial or space power if they were fabricated at low temperatures on low-density polymer substrates. This paper presents a molecular level electrochemical approach that may permit direct deposition of morphologically homogenous, stoichiometric CIS-alloy absorber layers without high temperature post treatments. The paper investigates the effects of deposition parameters by monitoring voltammetric characteristics, pulsed flow/deposition waveforms and film composition with different deposition system configurations. It distinguishes the CIS formation reaction mechanisms in bulk and thin layer electrolytes and identifies two new deposition parameters to increase the content of difficult-to-electrodeposit metals like In and Ga. The results provide directions for low-temperature synthesis of device quality absorber layers for efficient, inexpensive PV modules.