Preparation of lead sulfide thin films by the atomic layer epitaxy process

Preparation of lead sulfide thin films on different substrates by the Atomic Layer Epitaxy process has been studied. Sulfur source was in all experiments H2S, but as lead source the following compounds were tested: bromide, iodide and acetate as well as thd (2,2,6,6-tetramethyl-3,5-heptanedione) and diethyldithiocarbamate chelates. The last complex gave the highest growth rate. The growth experiments were carried out at 300–350°C and the film thickness varied between 0.1 and 1 μm. The films were characterized by XRD, XRF, SEM, and by photoconductivity and Hall measurements. The results showed that the films were polycrystalline and randomly oriented. The conductivity was p-type and the carrier concentration and mobility were comparable with those found in films deposited by traditional chemical methods.