Using two different experimental techniques, namely, chemical vapordeposition (CVD) and physical vapor deposition (PVD), we deposited a Leadsulphide (PbS) thin films with a very small lifetime. We investigated themorphology of the obtained PbS films using various techniques i.e.AFM, SEM,EDAX, AES and HRTEM . In the case of CVD, we found that the surface consists ofgrains with dimensions in the plane (diameter to 300 nm and height up to 200nm), while the same order of the grain size has been observed for PVD. On theother hand, SEM investigation reveals that the PbS particles with variousmorphologies of both films have uniform and the particle size distribution.Small amount of Sodium was obtained from EDXS studies, which is may originatefrom the substrate where the deposition process has been produced attemperature 550-600 deg. and for CVD at minimum accelerating voltage 5kVsilicon are presented in the spectrum, which means that the region for X-raygeneration voltage data exceeds the thickness of the films (where the thicknessof films about 0.4 micron). AES confirm that the surface layer of these films(PVD) containing carbon and oxygen and it has a thickness of 0.1micron. At adepth of 1.3 microns in films these elements is again increased, whichcorresponds to the film thickness of 1.5 micron. Layers of PVD films are seenby HRTEM and the studies confirm that oxygen-layer located on top of thestructure, while the layers of CVD films have not only the oxygen along thecrystallite boundaries, but also accumulate in the depth of the boundary withthe substrate. Our results of morphology indicate that changing in spectralcharacteristics of films deposited by (CVD and PVD) is related to the structureand crystalline size.
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