Doping Effects on the Characteristics of Fe:ZnO Films: Valence Transition and Hopping Transport

作者：Wang L M^*; Liao Jyh Wei; Peng Zi An; Lai Jian Hong

来源：Journal of the Electrochemical Society, 2009, 156(2): H138-H142.

DOI：10.1149/1.3035825

• carrier density
• carrier mobility
• doping
• electrical resistivity
• ferromagnetic materials
• glass
• hopping conduction
• II-VI semiconductors
• iron
• magnetic hysteresis
• magnetic thin films
• semiconductor thin films
• semimagnetic semiconductors
• sputter deposition
• wide band gap semiconductors
• zinc compounds

Ferromagnetic and conductive Fe-doped ZnO films were deposited on glass substrates by magnetron radio frequency sputtering. The crystalline structure and electrical characteristics were investigated to achieve optimum growth conditions. The films are grown with the orientations < 001 > perpendicular to the film plane and show ferromagnetic magnetization vs field (M-H) hysteresis curves at room temperature. With the optimum growth temperature of 450 degrees C and Fe dopant of Fe/Zn=1.2%, the electrical characteristics of mobility mu=10.31 cm(2)/V s, carrier concentration n=3.80x10(19) cm(-3), and resistivity rho=1.60x10(-2) Omega cm are obtained. Meanwhile, the resistivity as a function of temperature can be described by the variable-range hopping mechanism. Moreover, for films with a higher Fe dopant, it is deduced that the valence of iron changes from Fe(3+) to Fe(2+) with an increase in Fe dopant, leading to a reduction in conductivity and an enhancement in magnetization.

• 出版日期2009