Searching for a route to synthesize in situ epitaxial Pr2Ir2O7 thin films with thermodynamic methods

AbstractIn situ growth of pyrochlore iridate thin films has been a long-standing challenge due to the low reactivity of Ir at low temperatures and the vaporization of volatile gas species such as IrO3(g) and IrO2(g) at high temperatures and high PO2. To address this challenge, we combine thermodynamic analysis of the Pr-Ir-O2 system with experimental results from the conventional physical vapor deposition (PVD) technique of co-sputtering. Our results indicate that only high growth temperatures yield films with crystallinity sufficient for utilizing and tailoring the desired topological electronic properties and the in situ synthesis of Pr2Ir2O7 thin films is fettered by the inability to grow with PO2 on the order of 10 Torr at high temperatures, a limitation inherent to the PVD process. Thus, we suggest techniques capable of supplying high partial pressure of key species during deposition, in particular chemical vapor deposition (CVD), as a route to synthesis of Pr2Ir2O7.

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Thermodynamic Constraints for the In Situ MOCVD Growth of Superconducting Tl-Ba-Ca-Cu-O Thin Films

MRS Proceedings ◽

10.1557/proc-335-165 ◽

1993 ◽

Vol 335 ◽

Author(s):

William L. Holstein

Keyword(s):

Thin Films ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Chemical Vapor ◽

Organic Chemical ◽

Mocvd Growth ◽

Metal Organic ◽

Deposition Processes ◽

Organic Chemical Vapor Deposition

AbstractIn spite of several attempts, superconducting Tl-Ba-Ca-Cu-O thin films have not been successfully prepared in situ by metal organic chemical vapor deposition (MOCVD). Preparation of a phase by MOCVD requires that it be thermodynamically stable with respect to its decomposition into volatile species and other condensed phases. For MOCVD growth of Tl-Ba- Ca-Cu-O compounds in the presence of oxygen from reagents containing only C-H or C-H-O ligands, Tl2O(g) and TIOH(g) exhibit appreciable volatility. If reagents with ligands containing fluorine are used, the formation of volatile TIF(g) must also be considered. Thermodynamic data for these materials are compiled, and thermodynamic relationships between these gases, H2O(g) and HF(g) are established. The thermodynamic stability of TIOH(g) and TIF(g) makes the in situ growth of Tl-Ba-Ca-Cu-O compounds by MOCVD more difficult than their in situ growth by physical vapor deposition processes, for which Tl2O(g) is the only volatile TI-containing species present.

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Lead zirconate titanate thin films on ruthenium dioxide; in situ synthesis using organometallic chemical vapor deposition

Integrated Ferroelectrics ◽

10.1080/10584589408017015 ◽

1994 ◽

Vol 5 (3) ◽

pp. 221-227 ◽

Cited By ~ 5

Author(s):

M. de Keijser ◽

G. J. M. Dormans ◽

P. J. van Veldhoven

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Lead Zirconate Titanate ◽

Vapor Deposition ◽

Chemical Vapor ◽

Lead Zirconate ◽

In Situ Synthesis ◽

Ruthenium Dioxide ◽

Zirconate Titanate

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Ultra-high vacuum chemical vapor deposition and in situ characterization of titanium oxide thin films

Journal of Materials Research ◽

10.1557/jmr.1991.1913 ◽

1991 ◽

Vol 6 (9) ◽

pp. 1913-1918 ◽

Cited By ~ 31

Author(s):

Jiong-Ping Lu ◽

Rishi Raj

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Titanium Oxide ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

High Vacuum ◽

Chemical Vapor ◽

Titanium Isopropoxide ◽

Ultra High Vacuum

Chemical vapor deposition (CVD) of titanium oxide films has been performed for the first time under ultra-high vacuum (UHV) conditions. The films were deposited through the pyrolysis reaction of titanium isopropoxide, Ti(OPri)4, and in situ characterized by x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). A small amount of C incorporation was observed during the initial stages of deposition, through the interaction of precursor molecules with the bare Si substrate. Subsequent deposition produces pure and stoichiometric TiO2 films. Si–O bond formation was detected in the film-substrate interface. Deposition rate was found to increase with the substrate temperature. Ultra-high vacuum chemical vapor deposition (UHV-CVD) is especially useful to study the initial stages of the CVD processes, to prepare ultra-thin films, and to investigate the composition of deposited films without the interference from ambient impurities.

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Deposition and Characterization of Carbon Nitride Films by Laser Processed Methods

MRS Proceedings ◽

10.1557/proc-526-367 ◽

1998 ◽

Vol 526 ◽

Author(s):

Ashok Kumar ◽

R. Alexandrescu ◽

Michael A. George

Keyword(s):

Thin Films ◽

Comparative Analysis ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Carbon Nitride ◽

Pyrolytic Graphite ◽

Chemical Vapor ◽

Nitrogen Atmosphere ◽

Graphite Target

AbstractLaser assisted methods such as laser physical vapor deposition (LPVD) and laser induced chemical vapor deposition (LCVD) have been utilized to grow carbon nitride (CNx) films on various substrates. It has been shown that the both techniques produce good quality thin films of CNx. In LPVD, a laser beam (λ= 248 nm) has been used to ablate the pyrolytic graphite target in nitrogen atmosphere, where as CO2 laser was to irradiate carbon-nitrogen containing mixtures such as C2H2/N2O/NH3 in LCVD method. A comparative analysis will be presented in terms of structural properties of CNx films prepared by both techniques.

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In Situ Heteroepitaxial Bi2Sr2CaCu2O8 Thin Films Prepared by Metalorganic Chemical Vapor Deposition

MRS Proceedings ◽

10.1557/proc-335-285 ◽

1993 ◽

Vol 335 ◽

Author(s):

Frank Dimeo ◽

Bruce W. Wessels ◽

Deborah A. Neumayer ◽

Tobin J. Marks ◽

Jon L. Schindler ◽

...

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Metalorganic Chemical Vapor Deposition ◽

Chemical Vapor ◽

Oxide Phase ◽

Growth Conditions ◽

X Ray Diffraction ◽

Metalorganic Chemical

AbstractBi2Sr2CaCu2O8 thin films have been prepared in situ by low pressure metalorganic chemical vapor deposition using fluorinated β–diketonate precursors. The influence of the growth conditions on the oxide phase stability and impurity phase formation was examined as well as the superconducting properties of the films. Thin films deposited on LaAIO3 substrates were epitaxial as confirmed by x-ray diffraction measurements, including θ-2θ and φ scans. Four probe resistivity measurements showed the films to be superconducting with a maximum Tc0 of 90 K without post annealing. This Tc0 is among the highest reported for thin films of the BSCCO (2212) phase, and approaches reported bulk values.

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In situ single-liquid-source metal-organic chemical vapor deposition of (La0.8Ca0.2)MnO3 giant magnetoresistive films

Journal of Materials Research ◽

10.1557/jmr.1995.2166 ◽

1995 ◽

Vol 10 (9) ◽

pp. 2166-2169 ◽

Cited By ~ 26

Author(s):

Y.Q. Li ◽

J. Zhang ◽

S. Pombrik ◽

S. DiMascio ◽

W. Stevens ◽

...

Keyword(s):

Thin Films ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Chemical Vapor ◽

Organic Chemical ◽

Organic Solution ◽

Liquid Source ◽

Metal Organic ◽

Organic Chemical Vapor Deposition

A large magnetoresistance change (ΔR/RH) of −550% has been observed at 270 K in (La0.8Ca0.2)MnO3 thin films. The films were prepared in situ on LaAlO3 substrates by single-liquid-source metal-organic chemical vapor deposition. M(thd)n (M = La, Ca, and Mn, and n = 2, 3) were dissolved together in an organic solution and used as precursors for the deposition of (La0.8Ca0.2)MnO3 thin films. Deposition was conducted at an oxygen partial pressure of 1.2 Torr and a substrate temperature ranging from 600 °C to 700 °C. The mechanism for the large magnetoresistance change in this manganese oxide is briefly discussed.

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