11 - Rapid Thermal Annealing of (1−x)Ta2O5−xTiO2 Thin Films Formed by Metalorganic Decomposition

Abstract

A high-dielectric material with low leakage current is necessary for future generations of Dynamic Random Access Memory (DRAM) devices. Tantalum oxide (Ta2O5) is such a material that is compatible with gate insulator and DRAM cell capacitors. Tantalum oxide thin films are attractive for scaled down capacitor in Ultra-Large Scale Integrated (ULSI) circuits because of their high dielectric constant, lower leakage current, lower defect density, and high breakdown field strength. Extremely reliable Ta2O5 films with high-temperature stability are strongly required for successful integration into ULSI devices. Ta2O5 based composites have been studied for improving the dielectric and insulating properties. Dielectric and insulating properties of Ta2O5 can be dramatically increased through an 8% substitution of TiO2. The major focus rapid thermal annealing of (l-x)Ta2O5-xTiO2 thin films research has been done to improve the leakage current characteristics of crystalline Ta2O5 thin films deposited on Si substrates. Several fabrication methods, such as reactive sputtering, thermal oxidation, Plasma-Enhanced Chemical Vapor Deposition (PECVD), and Low-Pressure Chemical Vapor Deposition (LPCVD) have been employed to fabricate good quality Ta2O5 thin films. This chapter presents a paper that reports the rapid thermal annealing of (l-x)Ta2O5-xTiO2 thin films formed by Metal Organic Decomposition (MOD) technique.