Abstracts Book - IMRC 2018

• SA5-P025
STRESS, HARDNESS AND ELASTIC MODULES OF BISMUTH
TRIIODIDE (BiI3)
Natalia Coutinho 1 , Rafael Merlo 1 , Silvia Cucatti 1 , Fernando Alvarez 1 , Francisco Marques 1
1 Universidade Estadual de Campinas, Physics Institute, Brazil.
Bismuth triiodide (BiI3) has been studied aiming the development of lead-free
photovoltaic materials. BiI3 has been studied in X-ray detectors due to the high
density of the Bismuth element and can also be used in solar cells. In this work
we present stress, hardness, and elastic properties of BiI thin films deposited by
thermal evaporation. The stress was determined by the bending beam method
and the hardness by nanoindentation technique using a Berkovich diamond tip.
The stress of films is tensile and the hardness is approximately 0.7 GPa, been
softer than silicon (11GPa) or germanium (6GPa). The biaxial Young´s modulus
determined by the thermally induced bending method was 38 GPa and the
reduced Young´s modulus determined by nanoindentation was 29 GPa. The
evaporated BiI3 film is very homogenous and is a potential candidate for use in
solar cells.
Acknowledgment:
The authors would like to thank the Brazilian funding agencies CNPq
(grant INES/INCT 465423/2014-0), CAPES and FAPESP (grant 2012/10127-5) for
financial support
Keywords: Bismuth triiodide, stress, nanohardness
Presenting authors email: marques@ifi.unicamp.br