Growth and characterization of Sn doped ZnO thin films by pulsed laser deposition

Sn:ZnO thin films with different Sri concentrations were gown by pulsed laser deposition (PLD) onto single-crystal Si(001) substrates at an oxygen pressure of 2 x 10(-2) mbar and substrate temperature of 600 degrees C. The targets used were high density Sn:ZnO pellets with different Sn concentrations produced by mixing ZnO and SnO2 by conventional ceramic routes. A deep structural and electrical characterization was carried out in order to determine the role of an increasing Sri nominal concentration on the ZnO film transport properties: Only films with a nominal 0.1 at% Sn show an improvement of the transport properties, lower resistivity and higher donor concentration, with respect to pure ZnO thin films. For films with larger Sn nominal concentrations segregated SnZnO phases appear that lead to larger film resistivities and no increase in donor concentration. The 0.1 at% Sri film is accordingly a good candidate to study the possible room temperature ferromagnetism when co doping with Mn. Q 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.