Morphology control in chemical solution deposited lead selenide thin films on fluorine-doped tin oxide

Morphology control is demonstrated in chemical solution deposited lead selenide thin films on fluorine-doped tin oxide substrates. Trisodium citrate co-complexing agent was utilized as an additional degree of control over deposition parameters, in addition to the commonly used hydroxide complexing agent. Films were polycrystalline in all cases, and control over grain size and thickness was obtained upon varying trisodium citrate-to-hydroxide ratio. The morphology evolves from initially 7 nm grains with random orientation, continuing to columnar growth, and finally to grains of about 50 nm in diameter. For each trisodium citrate concentration a specific pH was determined in which deposition rate was maximal, resulting in columnar films up to 1,100 nm in thickness obtained after only 30 min of deposition.