Electrical properties of quaternary HfAlTiO thin films grown by atomic layer deposition

Quaternary alloyed HfAlTiO thin (~ 4–5 nm) films in the wide range of Ti content have been grown on Si substrates by Atomic Layer Deposition technique, and the effect of both the film composition and the interfacial reactions on the electrical properties of HfAlTiO films is investigated. It is shown that depending on the Ti content, the permittivity and the leakage current density Ileak in HfAlTiO films vary in the range k = 18 ÷ 28 and 0.01–2.4 A cm− 2, respectively. The incorporation of ultra thin SiN interlayer in Al/HfAlTiO/SiN/Si stack gives rise to the sharp (× 103) decrease of the Ileak ~ 6 · 10− 5 A/cm2 at the expense of the rather low capacitance equivalent thickness ~ 0.9 nm.