Evaporated LaAlO3 films for gate dielectrics

摘要

A gate dielectric containing LaAlO₃ and method of fabricating a gate dielectric contained LaAlO₃ produce a reliable gate dielectric having a thinner equivalent oxide thickness than attainable using SiO₂. The LaAlO₃ gate dielectrics formed are thermodynamically stable such that these gate dielectrics will have minimal reactions with a silicon substrate or other structures during processing. A LaAlO₃ gate dielectric is formed by evaporating Al₂O₃ at a given rate, evaporating La₂O₃ at another rate, and controlling the two rates to provide an amorphous film containing LaAlO₃ on a transistor body region. The evaporation deposition of the LaAlO₃ film is performed using two electron guns to evaporate dry pellets of Al₂O₃ and La₂O₃. The two rates for evaporating the materials are selectively chosen to provide a dielectric film composition having a predetermined dielectric constant ranging from the dielectric constant of an Al₂O₃ film to the dielectric constant of a La₂O₃ film. In addition to forming a LaAlO₃ gate dielectric for a transistor, memory devices, and information handling devices such as computers include elements having a LaAlO₃ gate electric with a thin equivalent oxide thickness.