An MOCVD Approach to High-k Praseodymium-Based Films

New high‐k dielectric thin films have become of increasing interest over the last few years in the search for an alternative material to SiO2 gate insulators in MOS devices. Lanthanide oxides have been studied as potential candidates for SiO2 replacement. In this review, a description of the different CVD approaches to fabricating praseodymium oxide and silicate films with dielectric properties is presented. In particular, thermally activated and liquid‐injection metal‐organic (MO) CVD as well as atomic layer deposition (ALD), developed in recent years, are discussed. Examples highlighting the importance of different praseodymium precursors on the deposited phases are given. Special emphasis is placed upon deposition parameters crucial to obtain Pr2O3 films and upon interfacial characterization. In addition, dielectric properties have been correlated to structural and compositional characteristics of praseodymium‐containing films. A description of the different CVD approaches to fabricating praseodymium oxide and silicate high‐k films is presented. Special emphasis is placed upon the fabrication of Pr2O3 films through chemical techniques such as thermal CVD, liquid‐injection CVD, and ALD. An overview of both the achievements and challenges has been given from different points of view, from the most suitable precursors to the most intriguing issues of thin‐film fabrication and their stability on silicon substrates.