Sputtering solid electrolytes

Fabrication techniques, especially the preparation of thin films of functional materials, have made major progress in recent years. Thin-film solid electrolytes in the range of several nanometers up to several micrometers have been prepared successfully. The most important reason for the development of thin-film electrolytes is the reduction in the ionic resistance, but there is also the advantage of the formation of amorphous materials with stoichiometries which cannot be achieved by conventional techniques of forming crystalline compounds. It has often been observed that thin-film electrolytes produced by vacuum evaporation or sputtering provide a struc-... 

Direct-current sputtering is not generally applicable for the preparation of thin-film solid electrolytes since these compounds are electronic insulators. The target surface would be charged with the same polarity as that of the ions in the plasma, and the sputtering plasma would rapidly break down. 

Figure 9. The variation of the EMF for Na2S0,-Y2(S0 )2 Si02 (48.1 11.8 40.1) solid electrolyte with the S0 gas concentration (Pt sputtering on working electrode surface only)...

Keywords structure of films, films of zirconia-based solid electrolytes, ion plasma sputtering, scanning electron microscope, transmission electron microscopy. 

The structure and the formation of films of a zirconia-based solid electrolyte, which were prepared by ion plasma sputtering, were studied using scanning and transmission electron microscopy methods. 

Considering the obtained experimental data, it is possible to propose a model of the formation of a porous structure of the films of zirconia-based solid electrolytes. The model assumes the formation of pores and submicropores when vacancies, which are trapped during sputtering of the solid-electrolyte films (the sputtering temperature was Tf < 0.3Tmeit), pass to sinks and then condense [2,3,4,5], The sinks are boundaries between the crystallites forming the film structure. 

The transmission electron microscopy was used to study the initial stage of the formation of the films of zirconia-based solid electrolytes, which were prepared by ion plasma sputtering on a glass-ceramic substrate having a thin ( 10 nm) layer of amorphous carbon. 

The simultaneous analysis of the results of the study into the structure and the formation of the solid-electrolyte films led to the following conclusion the nanocrystalline structure of the solid-electrolyte films at the initial stage of their formation caused the appearance of a columnar structure of the films of the zirconia-based solid electrolyte during their sputtering. 

West WC, Whitacre JF, Lim JR. Chemical stability enhancement of lithium conducting solid electrolyte plates using sputtered LiPON thin films. J Power Sources. 2004 126(1-2) 134-8. 

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