Praseodymium based dielectrics: Metal-Organic Chemical Vapor Deposition (MOCVD) growth, characterization and applications

Rare earth oxide thin films are of interest for several purposes including optical coatings, catalytic agents and/or supports, protective coatings, etc. Among the rare earth oxides, praseodymium oxides have been studied for many applications, such as component of varistor ceramic materials, photocatalytically active materials, and anode for organic light-emitting diodes and as dielectrics for microelectronic applications. The most interesting and studied praseodymium dielectrics include: h-Pr2O3, praseodymium silicates and praseodymium aluminates. In the following, a description of the different MOCVD approaches to fabricate praseodymium oxides, silicates and aluminates films with dielectric properties is presented. The MOCVD technique is a well-established, versatile and widely used method for producing technologically important thin films, ranging from metals to semiconductors, insulators and superconductors, with tailored properties. MOCVD compared to other deposition techniques offers the advantage of a great process simplicity, cheapness and conformal coverage achievable over complex three-dimensional topologies, and amenability to very large-scale depositions with low-cost apparatus. Thus the MOCVD processes to growth pure Pr-containing materials are discussed ranging from the precursors to the deposition parameters. Moreover, a detailed characterization of the final structure of the deposited films is supplied since it is mandatory in order to achieve a fundamental understanding for the electronic and chemical properties of the obtained materials in the perspective of their applications in microelectronics devices.