Pulsed and continuous wave solid phase laser annealing of electrodeposited CuInSe2 thin films

Cu(In, Ga)Se-2 (CIGS) thin film photovoltaic absorber layers are primarily synthesized by vacuum based techniques at industrial scale. In this work, we investigate non-vacuum film synthesis by electrochemical deposition coupled with pulsed laser annealing (PLA) and or continuous wave laser annealing (CWLA) using 1064 nm laser. PLA results indicate that at high fluence (>= 100 mJ/cm(2)) CuInSe2 films melt and dewet on both Mo and Cu substrates. In the submelt PLA regime (<= 70 mJ/cm(2)) no change in XRD results is recorded. However CWLA at 50 W/cm(2) for up to 45 s does not result in melting or dewetting of the film. XRD and Raman data indicate more than 80% reduction in full width at half maximum (FWHM) in their respective main peaks for annealing time of 15 s or more. No other secondary phases are observed in XRD or Raman spectrum. These results might help us in setting up the foundation for processing CIGS through an entirely non-vacuum process.