Intermolecular interaction between rare earth and manganese precursors in metalorganic chemical vapor deposition of perovskite manganite films

Abstract

The gas‐phase reaction mechanism was investigated in liquid delivery metalorganic chemical vapor deposition (MOCVD) of praseodymium and lanthanum manganite films. We studied the gas‐phase behavior of praseodymium, lanthanum, and manganese precursors under actual CVD conditions by in situ infrared absorption spectroscopy. The rate of the decrease of the infrared absorbance due to Pr(DPM)3 was almost constant even if Mn(DPM)3 was added, indicating that the intermolecular interaction between Pr and Mn precursors in the gas phase is relatively weak in MOCVD of praseodymium manganite films. On the other hand, the temperature dependence of the infrared absorption indicates that the thermal decomposition of La(DPM)3 was promoted in the presence of Mn(DPM)3. The significant intermolecular interaction occurs between La and Mn precursors in the gas phase in MOCVD of lanthanum manganite films. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Molecular Engineering of MnII Diamine Diketonate Precursors for the Vapor Deposition of Manganese Oxide Nanostructures

“…An important point of this study is the functional validation of MnL 2 ⋅ TMEDA compounds to assess their potential as CVD precursors for the fabrication of manganese oxide nanosystems. Preliminary deposition experiments were carried out on both Si(100) and SiO 2 substrates, by using vaporization (≤65 °C) and growth (400 °C) temperatures lower than those previously adopted in vapor phase processes from conventional manganese precursors, such as Mn(hfa) 2 and Mn(dpm) 3 , and also from Mn(hfa) 2 ⋅ TMEDA ,,. The obtained brownish samples, characterized by a good adhesion to the substrate, were preliminarily investigated by X‐ray diffraction (XRD, Figure ), which revealed the formation of body‐centered tetragonal Mn 3 O 4 [haussmannite; space group: I 4 1 / amd ; lattice parameters a= 5.762 Å, c= 9.470 Å; average crystallite size=(40±5) nm], with Mn III and Mn II centers in octahedral and tetrahedral sites, respectively (Figure , inset).…”

Manganese(II) Molecular Sources for Plasma-Assisted CVD of Mn Oxides and Fluorides: From Precursors to Growth Process

“…[21][22] So far, only a few reports on the preparation of MnF2 layers by ALD 23 and CVD 8 are present in the literature, whereas most studies have been dedicated to the synthesis of supported Mn oxide systems. In this context, several molecular precursors have been proposed and tested, encompassing different manganese bis(amidinates), 18,24 bis(ethylcyclopentadienyl)manganese 1,23,25-29 and various -diketonates, as, for instance, Mn(dpm)3 (Hdpm = 2,2,6,6-tetramethyl-3,5-heptanedione), [2][3]30 Mn(acac)2(H2O)2 (Hacac = 2,4pentanedione), 20 and Mn(hfa)2(H2O)2. 31 Some of these works have reported on the formation of Mn(II), 29 Mn(III) oxides, 2 Mn5O8, 1 as well as Mn3O4 3,32 and MnO2.…”

Metal‐Organic Chemical Vapor Deposition of Oxide Perovskite Films: A Facile Route to Complex Functional Systems

“…One of the most used techniques to investigate the gas‐phase reaction mechanisms during the epitaxial development of perovskite oxide layers is the in situ IR absorption spectroscopy. [ 29a ] Optical methods are the most powerful and challenging approaches to monitor film growth. [ 29b ] Among them, spectroscopic ellipsometry, reflectance difference spectroscopy, and Raman, are applied as tools to characterize the sample in growth.…”