Physics and Technology of Nanostructured Materials V

ISBN: 9783035717938 出版年：2020 页码：392 Nikolay Gennadievich Galkin Trans Tech Publications Ltd

Resistivity, r (T), and Hall coefficient in weak (B < 1 T) magnetic fields, R (T), are investigated in Ca2Si and CaSi2 films at temperatures T between ~ 20 - 300 K. In CaSi2, r (T) is typical of metals increasing with T within the whole temperature range. On the other hand, the resistivity of Ca2Si is pertinent of semiconductors. Namely, it is activated below T ~ 200 K, exhibiting different slopes of ln r vs. T -1 plots at lower and higher T, and a weak increase between T ~ 200 - 300 K. Both materials demonstrate a complex dependence of R (T), including a change of the sign. Transport properties above have been analyzed assuming two groups of charge carriers, electrons and holes, contributing them.