Quantifying the Extent of Ligand Incorporation and the Effect on Properties of TiO₂ Thin Films Grown by Atomic Layer Deposition Using an Alkoxide or an Alkylamide

Abstract

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Electrochemical Stability of n-Si Photoanodes Protected by TiO2 Thin Layers Grown by Atomic Layer Deposition

“…they do not consist of particles) but, depending on the growth conditions, they include a variable concentration of pores and GBs. As shown in a previous work, 27 open porosity can be observed for as-grown samples but the pores are closed during the annealing. Such thermal treatment has been carried out for all films to avoid any direct deleterious contact between the silicon and the electrolyte.…”

“…This can be easily correlated to morphology of the film that has been fully described in our previous work. 27 At low deposition temperature with TTIP, the TiO 2 film contains some tiny closed pores and, as seen on Fig. 2, the crystallite size is much smaller than with TDMAT.…”

“…In the present work, the samples have always been annealed because as-grown layers are amorphous and they contain a variable amount of precursor ligands that are dissolved when the films are immersed in the electrolyte. 27 A contact is then established between the alkaline solution and Si through the tiny porosity of TiO 2 . Si and KOH can react according to Eq.…”

In situ ellipsometry monitoring of TiO2 atomic layer deposition from Tetrakis(dimethylamido)titanium(IV) and H2O precursors on Si and InSkopin1, Abdukayumov2, Younes3 et al. 2021Thin Solid Films7010View full textAdd to dashboardCite

“…Ti[(CH 3 ) 2 N] 4 or Tetrakis(dimethylamido)titanium(IV) (hereinafter TDMAT) and water. Despite the significant number of publication reporting on TiO 2 ALD from TDMAT and water [12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,31,33], there is no clear idea of all the possible chemical reactions on the surface during the growth process and also there is no unique behavior of growth curves (Growth Per Cycle) as a function of the growth temperature. Additionally, it was shown that the TiO 2 initial growth stages depend on substrate chemistry, as in the case of ZnO ALD [34,35,36,37], TiO 2 exhibit different types of growth depending on the surface [15,29].…”

Atomic Layer Deposition of CeOx Nanoclusters on TiO2

“…This mechanism involves precursor adsorption, proton transfer, and ligand elimination process, which has also been investigated in other metal oxide ALD processes such as TiO2 and SiO2. [36][37][38][39][40][41] In this study, we have studied the adsorption and ligand elimination process for two cerium precursors Tris(methylcyclopentadienyl)cerium(III) (Ce(MeCp)3) and Tetrakis(2,2,6,6tetramethyl-3,5-heptanedionato)cerium(IV) (Ce(TMHD)4) on TiO2 using density functional theory, while ALD experiments are carried out with Tris(i-propylcyclopentadienyl)cerium(III), Ce( i PrCp)3 and Ce(TMHD)4.…”