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119 Sn

CEMS study of Sb doped SnO2 film

K. Nomura1 · E. Kuzmann2,3 · V. K. Garg3 · A. C. de Oliveira3 · S. Stichleutner2,4 · Z. Homonnay2

© Springer International Publishing Switzerland 2016

Abstract Sb doped SnO2 films prepared by DC sputtering and heating were characterized by 119 Sn conversion electron M¨ossbauer spectrometry (CEMS). An asymmetric doublet was observed in the M¨ossbauer spectra of 1 %, 3 %, and 10 % Sb doped SnO2 films. The peak ratios of doublets are considered to be due to the columnar crystal growth on the substrate. With the doping level of Sb, both the isomer shift (δ) and the quadrupole splitting () increased. After annealing, δ increased and  decreased for each sample. These results suggest the followings. The electron doping of the SnO2 lattice by pentavalent Sb induces the increase of the electron density at the SnIV nucleus. The annealing process leads to more

This article is part of the Topical Collection on Proceedings of the International Conference on the Applications of the M¨ossbauer Effect (ICAME 2015), Hamburg, Germany, 13-18 September 2015  E. Kuzmann

[email protected] K. Nomura [email protected] 1

PIRC, Tokyo University of Science, 2641 Yamazaki, Noda, 278-8501 Japan

2

Institute of Chemistry, E¨otv¨os Lor´and University, P´azm´any P´eter s´et´any 1/A, Budapest, H-1117, Hungary

3

Institute of Physics, University of Bras´ılia, 70919-970 Bras´ılia DF, Brazil

4

Centre for Energy Research, Hungarian Academy of Sciences, Konkoly Thege u´ t 29-33, Budapest, H-1121, Hungary

5

Hyperfine Interact (2016) 237:5

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complete accommodation of the Sb dopant that results in more effective electron doping and therefore increasing isomer shift for tin. Simultaneously, the distortion of the lattice caused by Sb is relaxed and the quadrupole splitting decreases. Keywords

119 Sn

M¨ossbauer spectroscopy · Sb doped SnO2 · Structural information

1 Introduction Transparent and conductive films are useful for solar cell and light devices applications, catalysis, gas sensors, etc.. We have studied earlier the magnetic properties of SnO2 films doped with iron [1], as well as the magnetic properties and defect structure of SnO2 doped with Fe and Sb using conversion electron M¨ossbauer spectrometry (CEMS) [2] and even depth selective 57 Fe CEMS [3]. We have also performed theoretical ab initio calculations on these systems [4]. Sb doped SnO2 films are frequently used as a base film for various applications. In this study, these oxide films were analysed by 119 Sn CEMS. We focused on the effect of Sb doping on DC sputtered and annealed SnO2 films.

2 Experimental 1 %, 3 % and 10 % Sb doped SnO2 films (the percentage value refers to the molar ratio of Sb to Sn) on quartz glass substrate were prepared by DC sputtering, and annealed at 500o C for 2 hours in air. 119 Sn conversion electron M¨ossbauer (CEM) spectra were recorded by a conventional M¨ossbauer spectrometer (WISSEL Co.) with a flowing gas (96 % He + 4 % CH4 ) proportional counter (RANGER Co.) at room temperature