Synthesis of novel volatile niobium precursors containing carboxamide for Nb2O5 thin films

• Published in: Polyhedron Vol. 200; pp. 115134 - 115139
• Main Authors: Min Hwang, Jeong, Yeon Kim, Na, Shin, Sunyoung, Hun Lee, Ji, Yeon Ryu, Ji, Eom, Taeyong, Keun Park, Bo, Gyoun Kim, Chang, Chung, Taek-Mo
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 15.05.2021; Elsevier
• Subjects: Atomic layer deposition; Carboxamide; Chemistry; Chemistry, Inorganic & Nuclear; Crystallography; Niobium; Physical Sciences; Precursor chemistry; Science & Technology; Structure elucidation; Carboxamide; Atomic layer deposition; Structure elucidation; Niobium; Precursor chemistry; ALKYL; TANTALUM; COMPLEXES; WATER
• ISSN: 0277-5387; 1873-3719
• DOI: 10.1016/j.poly.2021.115134

Series of niobium precursors with imido group and N-alkoxy carboxamide ligands were synthesized and fully analyzed by NMR, FT-IR, EA and TGA. All prepared complexes were able to be distilled and sublimed under reduced pressure, and expected potential precursors for niobium containing films. [Display omitted] A series of novel Nb(V) tBu-imido/N-alkoxy carboxamide complexes, NbCl2(NtBu)(pyridine)(edpa) (1), NbCl2(NtBu)(pyridine)(mdpa) (2), and Nb(NtBu)(mdpa)3 (3), were successfully synthesized by metathesis reaction between Nb(NtBu)Cl3(py)2 and several equivalents of Na(edpa) (edpaH = Nethoxy-2,2-dimethylpropanamide) and Na(mdpa) (mdpaH = N-methoxy-2,2-dimethylpropanamide). These complexes could potentially serve as precursors for Nb-containing thin films. Compounds 1–3 were characterized by FT-IR and 1H and 13C NMR spectroscopies, elemental analysis, and thermogravimetric analysis (TGA). Single crystal X-ray diffraction analysis suggested that complex 3 has a distorted pentagonal bipyramidal geometry around the central Nb atom, with three bidentate mdpa ligands and one tBu imido group saturating the coordination. TGA analysis revealed that the thermal characteristics of 3 were superior to those of 1 and 2. All prepared complexes were able to be distilled or sublimed and expected potential precursors for the fabrication of thin films.