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In the past decade, there have been numerous studies on the colossal magnetoresistance CMR effect of the mixed-valence perovskites: rare earth manganites RE1-XMXMnO3 (RE = rare-earth, M = Ca, Sr, Ba, Pb) (Millis et al., 1996; Ramirez, 1997; Evetts et al., 1998; Tokura, 2000; and Prellier et al., 2001). These CMR oxides in thin-film form are especially attractive for their potential applications in magnetic random access memory, magnetic field sensor, hard disk read-heads and infrared detectors (Steinbei et al., 2000; and Haghiri-Gosnet and Renard, 2003). In addition, understanding the novel transport and magnetotransport properties of these materials is a substantial challenge. One of the fruitful endeavors in this field has been the growth of good quality films with appreciable magnetoresistance (MR) and high ferromagnetic transition temperature (Tc), preferably above 300 K. The magnetic and electrical properties of the films of these Colossal Magneto Resistance (CMR) oxides are very sensitive to the material processing parameters. The magnetotransport properties in these perovskite systems are governed by the well-known double exchange between Mn+3 and Mn+4 pairs as well as the temperature-dependent polaronic interactions that localize charge carriers via Jahn-Teller distortion around the Mn+3O6 octahedras (Tsuda et al., 2000; and Mannella et al., 2004). Epitaxial thin films of Nd0.7Sr0.3MnO3 (NSMO) or Nd0.7Ca0.3MnO3 (NCMO) have been prepared over the last few years by a number of methods, such as Pulsed Laser Deposition (PLD), sputtering, Metal Oxide Chemical Vapor Deposition (MOCVD) and Chemical Solution Deposition (CSD). CSD techniques provide many advantages such as low cost, easy setup and coating of large areas. Control of stoichiometry and uniformity of these films depends highly on the reactivity of the chemicals used in the preparation of solutions. Moreover, film crystallinity, microstructure, and epitaxial relationships to the substrate need to be controlled in order to obtain the highest quality of epitaxial CMR films (Jin et al., 1999). The CMR properties of these films are crucially dependent on the oxygen stoichiometry, and need to be annealed after deposition. Well-characterized experimental data as a function of strain and oxygen deficiency is necessary for comparing the various results published in the literature, and for the use of these materials as commercial magnetoresistive devices. It is therefore important to fabricate and characterize high quality epitaxial films using a simple, inexpensive and reproducible method in which the stoichiometry can be accurately predetermined and controlled. The magnetic and electrical properties of the films of these CMR oxides are very sensitive to the material processing parameters, such as the method of deposition, the temperature of growth, post-deposition annealing treatment (Paranjape and Raychaudhuri, 2002), quality of epitaxy and mismatch with the substrate (Jin et al., 1995).
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