Magnetic and Structural Properties of Mg(Fe2-xAlx)O4 Thin Films

The magnetic and the structural properties of Mg(Fe2-xAlx)O4 thin films prepared by using the sol-gel method were investigated. The Mg(Fe2-xAlx)O4 thin films crystallized into the single spinel phase in air and the crystallization temperature increased from 500℃ (x = 0) to 800℃(x = 2) with increasing Al content x. The lattice constant and the grain size was decreased when the Al content increased in the Mg(Fe2-xAlx)O4 thin films annealed at 800℃. The Mg(Fe2-xAlx)O4 thin films with x ≤ 1.2 had Neel temperatures (TN) higher than room temperature while the thin films with x ≥ 1.6 lost ferrimagnetic ordering. The Mg(Fe2-xAlx)O4 thin films show the largest saturation magnetization (Ms) value of 87 emu/cm3 at x = 0.0 and the magnetization decreased with increasing Al content(x). The magnetic characteristics of the Mg(Fe2-xAlx)O4 thin films are discussed in terms of the cation distributions over the octahedral and the tetrahedral sites in the spinel structure. KCI Citation Count: 13