The Influence of the Pretreatment of Si Substrate on the Growth of PbS Thin Films in the SILAR Technique

摘要

The successive ionic layer adsorption and reaction (SILAR) technique used to deposit PbS, involved the growth of thin films from dilute solutions (0.2M Pb(CH_3OO)_2 as lead and 0.4 M CH_3CSNH_2 (Thioacetamide) as sulphur precursor) ionic layer by ionic layer at room temperature and normal pressure. The growth of the PbS thin film on Si was characterized by XRD and AFM. The effect of the Si substrate pretreatment (by concentrated H_2SO_4 +H_2O_2 "piranha" or by HF) on the film growth has been studied. After HF pretreatment the PbS film growth had a more clear 3D mode as compared with growth after H_2SO_4 +H_2O_2 treatment.