ALD OF AMORPHOUS LANTHANIDE DOPED TiOX FILMS

摘要

The use of atomic layer deposition (ALD) to form an amorphous dielectric layer of titanium oxide (TiO_X) doped with lanthanide elements, such as samarium, europium, gadolinium, holmium, erbium and thulium, produces a reliable structure for use in a variety of electronic devices. The dielectric structure is formed by depositing titanium oxide by atomic layer deposition onto a substrate surface using precursor chemicals, followed by depositing a layer of a lanthanide dopant, and repeating to form a sequentially deposited interleaved structure. Such a dielectric layer may be used as the gate insulator of a MOSFET, as a capacitor dielectric, or as a tunnel gate insulator in flash memories, because the high dielectric constant (high-k) of the layer provides the functionality of a thinner silicon dioxide layer, and because the reduced leakage current of the dielectric layer when the percentage of the lanthanide element doping is optimized.