Ohmic contacts and n-type doping on TixCr2-xO3 films and the temperature dependence of their transport properties

A procedure to dope n-type Cr-2 (-) xTixO3 thin films is proposed. Besides doping the material, at the same time the method forms ohmic contacts on TixCr2 O--x(3) films. It consists on the deposition of 10 nm Ti and 50 nm Au, followed by thermal annealing at 1000 degrees C for 20 min in N-2 atmosphere. Ohmic contacts were formed on three samples with different composition: x = 0.17, 0.41 and 1.07 in a van der Pauw geometry for Hall effect measurements. These measurements are done between 35 K and 373 K. All samples showed n-type nature, with a charge carrier density (n) on the order of 10(20) cm(-3), decreasing as x increased. As a function of temperature, n shows a minimum around 150 K. while the mobilities have an almost constant value of 11,28 and 7 cm(2)V(-1) s(-1) for x = 0.17, 0.41 and 1.07, respectively. (C) 2010 Elsevier B.V. All rights reserved.