Surface energies of AlN allotropes from first principles

In this letter we present first-principles calculations of the surface energies of rock-salt (B1), zinc-blende (B3) and wurtzite (B4) AlN allotropes. Of several low-index facets, the highest energies are obtained for monoatomic surfaces (i.e. of only either Al or N atoms): γ{111}B1=410meV/Å2,γ{100}B3=346meV/Å2,γ{111}B3=360meV/Å2 and γ{0001}B4=365meV/Å2. The difference between Al- and N-terminated surfaces in these cases is less then 20 meV/Å2. The stoichiometric facets have energies lower by 100 meV/Å2 or more. The obtained trends could be rationalized by a simple nearest-neighbour broken-bond model.

[1]  Wang,et al.  Correlation hole of the spin-polarized electron gas, with exact small-wave-vector and high-density scaling. , 1991, Physical review. B, Condensed matter.

[2]  R. Powell,et al.  Synthesis of metastable epitaxial zinc‐blende‐structure AlN by solid‐state reaction , 1992 .

[3]  C. Mitterer,et al.  Self-organized nanostructures in the Ti–Al–N system , 2003 .

[4]  E. Stergar,et al.  Decomposition pathways in age hardening of Ti-Al-N films , 2011 .

[5]  R. Newnham,et al.  Materials for high temperature acoustic and vibration sensors: A review , 1994 .

[6]  V. Chawla,et al.  Interfacial coherency stress distribution in TiN/AlN bilayer and multilayer films studied by FEM analysis , 2012, Computational materials science.

[7]  G. Kresse,et al.  From ultrasoft pseudopotentials to the projector augmented-wave method , 1999 .

[8]  R. Becker Die Keimbildung bei der Ausscheidung in metallischen Mischkristallen , 1938 .

[9]  Kresse,et al.  Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. , 1996, Physical review. B, Condensed matter.

[10]  M. Willander,et al.  III–nitrides: Growth, characterization, and properties , 2000 .

[11]  Miss A.O. Penney (b) , 1974, The New Yale Book of Quotations.

[12]  D. Holec,et al.  Pressure-dependent stability of cubic and wurtzite phases within the TiN-AlN and CrN-AlN systems , 2010 .

[13]  S. Kodambaka,et al.  Pathways of atomistic processes on TiN(001) and (111) surfaces during film growth: An ab initio study , 2003 .

[14]  K. Parlinski,et al.  Ab initio calculation of structural phase transitions in AlN crystal , 2006 .

[15]  O. Madelung Semiconductors: Data Handbook , 2003 .

[16]  E. Kozeschnik,et al.  On the Potential for Improving Equilibrium Thermodynamic Databases with Kinetic Simulations , 2007 .

[17]  G. G. Stokes "J." , 1890, The New Yale Book of Quotations.

[18]  J. Schneider,et al.  Energetic balance and kinetics for the decomposition of supersaturated Ti1- xAlxN , 2007 .