Atomic layer deposition of copper sulfide thin films

摘要: Abstract Atomic Layer Deposition (ALD) of copper sulfide (Cu x S) thin films from Cu(acac) 2 (acac = acetylacetonate = 2,4-pentanedionate) and H S as Cu precursors is reported. Typical self-saturated reactions (“ALD window”) are obtained in the temperature range T dep  = 130–200 °C for an average growth per cycle (GR) = 0.25 A/cycle. The morphology, crystallographic structure, chemical composition, electrical properties optical band gap were investigated using scanning electronic microscopy (SEM), X-ray diffraction under Grazing Incidence conditions (GI-XRD), reflectivity (XRR), energy dispersive spectrometry (EDS), Hall effect measurements, UV–vis spectroscopy. heavily p-doped (charge carrier concentration ~ 10 21  –10 22  cm − 3 ) with gaps 2.2–2.5 eV direct 1.6–1.8 eV indirect gaps. Depending on number ALD cycles, multiphase compounds (made digenite 1.8 S, chalcocite djurleite 31 16 covellite CuS) or single-phase via a mechanism that involves in-situ reduction loss sulfur by evaporation.