Thermal properties of TiO2 films grown by atomic layer deposition

Tutkimustuotos: Lehtiartikkelivertaisarvioitu

Tutkijat

  • M. R. Saleem
  • P. Silfsten
  • S. Honkanen
  • J. Turunen

Organisaatiot

  • NUST, National University of Sciences & Technology - Pakistan, SCME
  • University of Eastern Finland

Kuvaus

We study the thermal properties of amorphous TiO 2 thin films of various thicknesses t, grown by atomic layer deposition. The thermo-optic coefficient dn/dT and the temperature coefficient dρ/dT of film density ρ are determined from ellipsometric data in wavelength range 380 < λ < 1800 nm with the Cauchy model and the Lorentz-Lorenz relation. It is found that dn/dT exhibits negative values for films with t < 150 nm and positive values for thicker films, while no significant changes in the two coefficients take place if t < 200 nm. A qualitative physical explanation based on porosity of the thin films is suggested. Films with t = 60 nm are illustrated in detail at λ = 640 nm: the room-temperature values of the coefficients are found to be dn/dT = - 3.1 × 10 - 5°C - 1 and dρ/dT = - 4.8 × 10 - 5g cm - 3°C - 1.

Yksityiskohdat

AlkuperäiskieliEnglanti
Sivut5442-5446
Sivumäärä5
JulkaisuThin Solid Films
Vuosikerta520
Numero16
TilaJulkaistu - 1 kesäkuuta 2012
OKM-julkaisutyyppiA1 Julkaistu artikkeli, soviteltu

ID: 16984406