Semiconductor Physics, Quantum Electronics & Optoelectronics. 2011. V. 14, N 1. P. 071-076.

Non-ohmic conduction in tin dioxide based ceramics with copper addition
A.V. Gaponov1, A.B. Glot2

1Dnipropetrovsk National University, 72, Gagarin Ave., 49010 Dnipropetrovsk, Ukraine E-mail:
2Universidad Tecnológica de la Mixteca, Carretera a Acatlima km. 2.5, Huajuapan de León, Oaxaca, 69000, México E-mail:

Abstract. The current-voltage characteristics and temperature dependences of electrical conductivity in SnO 2 -Co 3 O 4 -Nb 2 O 5 -Cr 2 O 3 -CuO semiconductor ceramics are studied, and possible mechanism of non-ohmic conduction in these materials is discussed. Due to addition of CuO up to 0.5 mol.%, the nonlinearity coefficient is increased up to 75, and the electric field is decreased down to (at ). It makes CuO addition useful for the preparation of SnO 1 cm V 3900 − ⋅ 2 cm mA 1 − ⋅ 2 -based varistors. It is concluded that the electrical conduction is controlled by grain-boundary barriers. The activation energy of electrical conduction (the barrier height φ) is decreased with an increase in the electric field E. The higher slope of the E dependence at high fields can be related to a participation of minority carriers (holes). The addition of more than 0.5 mol.% CuO leads to degradation of the varistor effect due to percolation via quite conductive CuO- based intergranular phase.

Keywords: non-ohmic conduction, grain boundary, varistor, barrier height, tin dioxide ceramics.

Full Text (PDF)

Back to N1 Volume 14