TY - JOUR
T1 - Atomic Layer Deposition of Al2O3 Using Aluminum Triisopropoxide (ATIP)
T2 - A Combined Experimental and Theoretical Study
AU - Tai, Truong Ba
AU - Cao, Liao
AU - Mattelaer, Felix
AU - Rampelberg, Geert
AU - Hashemi, Fatemeh S.M.
AU - Van Ommen, J. Ruud
AU - Detavernier, Christophe
AU - Reyniers, Marie Françoise
PY - 2019
Y1 - 2019
N2 - The aluminum precursor plays a crucial role in the Al2O3 ALD process. To date, trimethylaluminum (TMA) is one of the most widely used precursors in experimental and theoretical studies. However, its application at industrial scale can pose safety risks since it is pyrophoric and extremely reactive with water. Aluminum alkoxides offer a promising alternative, but have received far less attention. A combined theoretical and experimental investigation is carried out on the Al2O3 ALD process using aluminum triisopropoxide (ATIP) as a prototypical example of Al-alkoxide precursors. The experimental results pointed out that the thermal ALD process using ATIP and water has a maximal growth per cycle (GPC) of 1.8 Å/cycle at temperatures of 150 to 175 °C. On the basis of the in situ mass spectrometry analysis and DFT calculations, the formation of the alumina film mainly occurs during the water pulse by ligand exchange reactions between water and adsorbed precursors, while during the ATIP pulse only adsorption of ATIP and/or its dissociation occur. Design of heteroleptic precursors containing alkoxide group as basic ligand is challenging, but greatly promising for future industrial scale Al2O3 ALD.
AB - The aluminum precursor plays a crucial role in the Al2O3 ALD process. To date, trimethylaluminum (TMA) is one of the most widely used precursors in experimental and theoretical studies. However, its application at industrial scale can pose safety risks since it is pyrophoric and extremely reactive with water. Aluminum alkoxides offer a promising alternative, but have received far less attention. A combined theoretical and experimental investigation is carried out on the Al2O3 ALD process using aluminum triisopropoxide (ATIP) as a prototypical example of Al-alkoxide precursors. The experimental results pointed out that the thermal ALD process using ATIP and water has a maximal growth per cycle (GPC) of 1.8 Å/cycle at temperatures of 150 to 175 °C. On the basis of the in situ mass spectrometry analysis and DFT calculations, the formation of the alumina film mainly occurs during the water pulse by ligand exchange reactions between water and adsorbed precursors, while during the ATIP pulse only adsorption of ATIP and/or its dissociation occur. Design of heteroleptic precursors containing alkoxide group as basic ligand is challenging, but greatly promising for future industrial scale Al2O3 ALD.
UR - http://www.scopus.com/inward/record.url?scp=85059641602&partnerID=8YFLogxK
U2 - 10.1021/acs.jpcc.8b09198
DO - 10.1021/acs.jpcc.8b09198
M3 - Article
AN - SCOPUS:85059641602
SN - 1932-7447
VL - 123
SP - 485
EP - 494
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
IS - 1
ER -