MoSe2 Formation from Selenization of Mo and Nanoparticle Derived Cu(In,Ga)Se2/Mo Films

The formation characteristics of MoSe₂ by selenization of Mo and nanoparticle derived Cu(ln,Ga)Se₂(CIGS)/Mo layers were investigated with a two-zone RTP (rapid thermal process) furnace to elucidate why the CIGS/Mo layer peels off the glass substrate when selenized under the high Se vapor pressure condition. It was found that the thickness of MoSe₂ linearly increased with Se evaporation temperature and substrate temperature. At a substrate temperature of 550degC and Se evaporation temperature of 450degC, 1.6mum thick MoSe₂ layer formed in 5 minutes with an expense of 0.4mum thick Mo. The formation of very thick MoSe₂ layer revealed that c-axis of hexagonal MoSe₂ is parallel to the Mo substrate. When the nanoparticle derived CIGS/Mo layers are selenized at a substrate temperature of 500degC and Se evaporation temperature of 450degC for 5 minutes, about 1.3mum thick MoSe₂ formed at CIGS and Mo interface without significant growth of CIGS particles, demonstrating that reaction rate of Se with Mo is much faster than that with CIGS nanoparticles