Recent developments in the III‐nitride materials

Abstract

We review a selection of recent research work on III-nitride materials, limiting the scope to bulk properties and quantum well structures. The different stages of development of the compounds AlN, GaN and InN are illustrated, with reference to the electronic properties demonstrated so far. The important alloy systems Al x Ga 1-x N and In x Ga 1-x N have quite different properties, still not understood in detail for high Al and In contents, respectively. Some important unresolved issues are highlighted, and possible future directions of the materials development are indicated.

Time-resolved photoluminescence properties of AlGaN/AlN/GaN high electron mobility transistor structures grown on 4H-SiC substrate

“…The decay time is expected to be the same or longer for the phonon replicas in comparison with NP lines as it was previously reported for GaN. 8,9 In addition, the 3.39 eV shows in TRPL a higher energy shift of ϳ2 meV under the PL rise process ͓see Fig. 7͑a͔͒ and a low energy shift of the same order under the PL decay ͓Fig.…”

Lattice parameters of bulk GaN fabricated by halide vapor phase epitaxy

“…Despite the remarkable progress in the III-nitride research and technology, some basic bulk properties of GaN and related materials remain uncertain and further technological developments are in need [1,2]. One of the main obstacles impeding further progress in the field is the lack of native substrates in the growth process and consequent difficulties to prepare strain-free material.…”

Exciton recombination in spontaneously formed and artificial quantum wells AlxGa1‐xN/AlyGa1‐yN (x<y∼0.8)

“…The application of these compounds with very large exciton binding energy exceeding 50 meV [2] can be hampered, however, by a relatively poor structural quality of the AlGaN-based heterostructures grown on commercially available substrates [3] and by a number of specific properties such as TM polarization of emission [4] and difficulties in p-type doping [5]. One more distinctive feature of III-nitride alloys is the easy formation of micro-and nanoscale compositional inhomogeneities that govern carrier mobility and recombination dynamics [6].…”