Materials - Titanium dioxide layers

Titanium dioxide layers


Titanium dioxide also known as titania (TiO2) thin flims are obtained by atomic layer deposition (ALD) on range of substrates, like Si, GaN, SiC, graphene, SiO2 etc. The material is formed in a double exchange chemical reaction between two reactants (precursors), such as a deionized water (oxygen precursor) and a titanium chloride - TiCl4 or tetrakis(dimetylamido)titanium(IV) - TDMAT (titanium precursor). TiO2 can be grown at the temperature range from 25°C to 450°C. The maximum size of the substrate is 20 cm of a diameter.



  • Thickness: 10 - 3000 nm
  • Growth rate: 0.1 nm/minute
  • Resistivity: > 108 Ωcm
  • Energy gap: 3.9 eV
  • Refractive index: 2.35 (635 nm)
  • Relative permittivity: 40±3
  • Hydrophobic properties
  • Surface roughness: 0.4 nm < RMS < 10 nm
  • Structure: polycrystalline - tetragonal phase or amorphous layers
  • Average transmission in visible spectra:> 80%
  • Uniformity of coatings



TiO2 is characterized by high refractive index, good stability, high chemical resistance, high hardness and high permittivity. This material, due to its physical and chemical properties, can be used as an insulator in electronic devices, as optical coatings in lasers and microscopes, as well as, barrier or protective layers in photovoltaic structures. Moreover, this material can be used in various types of sensors, and can be used in the manufacture of dental prostheses and implants in medicine.

Cross-section image of TiO2 on silicon substrate from scanning electron microscope (SEM).

TiO2 surface image (with RMS: 0.3 nm) on silicon substrate from atomic force microscope (AFM).

X-ray diffraction pattern (XRD) of polycrystalline in the tetragonal phase and amorphous layers of titanium dioxide . The layers were grown on a silicon substrate.