Naslov
On crystalline structure of TiO2 films grown by plasma-enhanced atomic layer deposition

Autori
Saric, Iva ; Peter, Robert ; Jelovica Badovinac, Ivana ; Kavre Piltaver, Ivna ; Ambrozic, Gabriela ; Omerzu, Ales ; Spreitzer, Matjaz ; Petravic, Mladen

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of abstracts: 16th Atomic Layer Deposition Conference / - , 2016

Skup
16th Atomic Layer Deposition Conference

Mjesto i datum
Dublin, Irska, 24.07.2016. - 27.07.2016

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
titanium dioxide ; atomic layer deposition ; plasma-enhanced ALD

Sažetak
Titanium dioxide (TiO2) is a multifunctional metal-oxide semiconductor with potential applications in diverse fields of technology such a s microelectronics, photocatalysis or medical devices. Recently, a possibility of applying the photo-catalytic TiO2 films grown on various organic (cellulose-based) and porous substrates in water purification have attracted much attention [1]. For this purpose, it is of crucial importance to grow thin films of well-defined anatase phase of TiO2 with large polycrystalline grains and controllable thickness. Namely, it has been shown that the photo-catalytic activity of the TiO2 films depends critically on the crystal structure and the grain size within the films [2]. The anatase crystal structure with large grains produces superior photo-catalytic activity compared to the rutile or amorphous phases of TiO2 [3]. Atomic layer deposition (ALD) has been established as a routine technique for the synthesis of thin TiO2 films, due to its simplicity, reproducibility, the high conformality of the obtained films and an excellent control of the layer thickness at the angstrom level. In addition, it allows growth of thin polycrystalline films at temperatures well below 100 °C using plasma-enhanced ALD (PEALD) technique, which is essential for depositing thin films on temperature-sensitive materials, such as organic substrates [4]. In this work, we have employed thermal ALD and PEALD for the growth of thin TiO2 films on Si substrates in a wide temperature range, from room temperature up to 300 0C. Films were grown using two titanium precursors: titanium tetrachloride, TiCl4, and tetrakisdimethylamino titanium, TDMAT, both in combination with H2O and/or oxygen plasma. The thermal ALD produces amorphous TiO2 films at all temperatures below 150 0C, while with PEALD, we were able to obtain the anatase phase of TiO2 at low temperatures. The crystal structure of TiO2 films was determined by x-ray diffraction, while the size of crystal grains, surface topography, conformity, composition and film thickness was studied with scanning electron microscopy. In addition, we have employed x-ray photoelectron spectroscopy for the study of composition and chemical bonding and secondary ion mass spectrometry for in-depth elemental analysis and film thickness measurements.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

POVEZANOST RADA