Role of hydrogen in surface reconstructions and growth of GaN
نویسندگان
چکیده
We present first-principles calculations for the atomic structure and energetics of hydrogenated GaN~0001! surfaces. The geometry of the most relevant surface reconstructions is discussed in detail. Finite-temperature effects are included through calculations of the Gibbs free energy and the stability of various surface reconstructions is analyzed in terms of a generalized surface phase diagram. A comparison with recent experiments elucidates the energetic and structural properties of GaN surfaces under growth conditions. © 2002 American Vacuum Society. @DOI: 10.1116/1.1491545#
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