Effect of the Helium Background Gas Pressure on the Structural and Optoelectronic Properties of Pulsed-Laser-Deposited PbS Thin Films.

This work focuses on the dependence of the features of PbS films deposited by pulsed laser deposition (PLD) subsequent to the variation of the background pressure of helium (P). The morphology of the PLD-PbS films changes from a densely packed and almost featureless structure to a columnar and porous one as the He pressure increases. The average crystallite size related to the (111) preferred orientation increases up to 20 nm for P ≥ 300 mTorr.