STABILITY OF LANGMUIR-BLODGETT FILM/ALUMINA, AND LANGMUIR-BLODGETT-FILM GOLD MULTILAYER STRUCTURES

A new type of hybrid Langmuir-Blodgett (LB) film/metal synthetic multilayer structure of CdSt2/Au (St = stearate) was reported for the first time. Three to six monolayers of CdSt2 or AlSt3 LB film and one layer of gold or Al2O3 film alternately formed a periodic multilayer of CdSt2/Au or AlSt3/Al2O3 with a periodicity of 10-20 nm. The stability of these samples kept at room temperature in a desiccator was studied by low angle X-ray diffraction. It is found that the structure of AlSt3/Al2O3 multilayer does not change after 14 months of storage. The CdSt2/Au multilayer structure with a CdSt2 LB film of three or or five monolayers is also stable. However, the CdSt2/Au samples prepared by an identical procedure with a CdSt2 LB film of four or six monolayers degraded completely within several months. This suggests that the role of the hydrophilic Cd(COO)2 end in a stable CdSt2/Au multilayer structure needs further investigation.