Bulk single-crystal growth of ternary AlxGa1−xN from solution in gallium under high pressure

Thermodynamics of the Al–Ga–N2 system

“…$66.38 kcal/mol for Ga and $ 79.25 kcal/mol for Al [25]), and more importantly, it is negligible compared to the corresponding p-dependent part of the gas component N 2 . The equilibrium pressure P Eq depends on the temperature and for ternary (Al,Ga)N is on order of 10 4 bar $10 9 Pa (N/m 2 ) (see Ref [8], Fig. 2).…”

“…(Al,Ga)N solid solutions have been produced as epitaxial layers using various growth methods [6,7], and only recently we succeeded in the growth of (Al,Ga)N single crystals using high pressure techniques [8].…”

“…The growth conditions and the extended equilibrium p-T phase diagram of (Al,Ga)N were previously published [8]. Here, we present the calculations of the standard Gibbs free energy, enthalpy and entropy of formation of the (Al,Ga)N crystals based on the experimental p-T growth conditions.…”

Wurtzite AlxGa1−xN bulk crystals grown by molecular beam epitaxy

“…However, such bulk GaN crystals are still not commercially available mainly due to the slow growth rate of less than 1 mm/hr and the small size of the crystals $1 cm 2 . There are only a few reports in the literature on the growth of bulk Al x Ga 1À x N crystals using Ga melt solutions under high nitrogen pressure (up to10 kbar) and at high temperatures (up to1800 1C) [4,5]. However, the size of bulk Al x Ga 1À x N crystals currently achieved by that method are still very small (up to $ 0.8 Â 0.8 Â 0.8 mm 3 ) [5].…”

Molecular beam epitaxy of free‐standing bulk wurtzite AlxGa1‐xN layers using a highly efficient RF plasma source

“…Therefore Al x Ga 1-x N substrates would be preferable to those of either GaN or AlN for many ultraviolet device applications. This has stimulated a search for methods to produce bulk Al x Ga 1-x N crystals with variable AlN content [2,3].…”