Experimental study of MgB2 decomposition

Abstract

The thermal stability of MgB2 has been studied experimentally to determine the role of thermodynamic and kinetic barriers in the decomposition process. The MgB2 decomposition rate approaches one monolayer per second at 650 C and has an activation energy of 2.0 eV. The evaporation coefficient is inferred to be ~ 10(-4), indicating that this process is kinetically limited. These values were inferred from in-situ measurements using a quartz crystal microbalance and a residual gas analyzer, in conjunction with ex-situ measurements of re-deposited material by Rutherford Backscattering Spectroscopy. The presence of a large kinetic barrier to decomposition indicates that the synthesis of MgB2 thin films conditions may be possible with vacuum processing, albeit within a narrow window in the reactive growth conditions.

1 figure. Submitted to Applied Physics Letter (03/20/01)

References in corpus (5)

• Boron Isotope Effect in Superconducting MgB${}_2$
• Superconductivity in Dense $Mg{B}_2$ Wires
• MgB2 superconducting thin films with a transition temperature of 39 Kelvin
• Thermodynamics of the Mg-B system: Implications for the deposition of MgB2 thin films
• Superconducting thin films of MgB2 on (001)-Si by pulsed laser deposition

Cited by in corpus (8)

• High Density MgB2 Obtained by Reactive Liquid Mg Infiltration
• In-situ growth of superconducting MgB2 thin films by molecular beam epitaxy
• Growth of high quality large area MgB2 thin films by reactive evaporation
• Superconducting properties of nanocrystalline MgB${}_2$ thin films made by an in situ annealing process
• Low Temperature Fabrication of MgB2
• Thermochemistry of MgB2 Thin Film Synthesis
• Influence of Mg deficiency in MgB2 single crystals on crystal structure and superconducting properties
• Effect of Rb and Cs-doping on superconducting properties of MgB2 thin films