First stages of growth of CdS films on different substrates

Cadmium sulfide films were grown on glass, silicon, and ITO substrates by c hemical-bath deposition (CBD) at 358 K, and studied by atomic force microsc opy, Auger electron microscopy and X-ray diffraction. CdS film growth initi ates immediately and thickness increases with deposition time. The rms roug hness of CdS films grown for 1 to 10 min (thicknesses of 10 to 70 nm) was m easured by atomic force microscopy. The roughness of films grown on ITO rem ains similar to that of the substrate regardless of deposition time. On the other hand, the roughness of CdS films grown on glass and silicon increase s with deposition time, finally reaching a roughness similar to that of fil ms grown on ITO. Auger profiles show that the CdS/substrate interface is no t abrupt and depends on the substrate. Substrate roughness plays an importa nt role during the initial CdS growth process. X-ray studies show that sili con substrates are not appropriate for CdS film growth by CBD. The most app ropriate substrate is ITO. (C) 1999 Elsevier Science B.V. All rights reserv ed.