Structure and electrical properties of pure and yttrium-doped HfO2 films by chemical solution deposition through layer by layer crystallization process

Abstract Pure and yttrium doped HfO 2 thin films were fabricated on Si (100) substrates by chemical solution deposition through a layer by layer crystallization process. We systematically investigated the effects of thickness and Y doped concentration on structure and electrical properties of the HfO 2 films. Results revealed that 4 nm thick undoped HfO 2 was crystallized into a t/c-phase due to the surface energy effect, and this higher symmetry phase could be retained up to a film thickness of 16 nm through the layer by layer crystallization process. This layer by layer crystallization process also required less Y doping to stabilize t/c-HfO 2 in thick films. The films showed a high dielectric constant about 42, low leakage current density of about 10 − 7  A/cm 2 (at 1 MV/cm) and a breakdown field up to 5 MV/cm. Considering the cost-effective deposition technique and good electrical properties, these films would be suitable for insulator applications in microelectronic devices.