Lattice-matched AlInN in the initial stage of growth

We investigated the dependence of the indium content of tenfold Al1−xInxN/GaN superlattice structures grown by metal organic vapor phase epitaxy on layer thickness and strain state. Growth conditions taken from a thick lattice-matched reference sample with an indium content of about 18% lead to reduced indium contents from 3% for 0.5 nm of Al1−xInxN to 16.5% for 5.0 nm, respectively. There is no evidence for dependences of the indium incorporation on the lattice mismatch between the Al1−xInxN and the subjacent layer. Additional supply of trimethylindium only shows a very slight, almost negligible influence on the indium content of these superlattice structures. Finally, we present a model explaining the behavior of the indium content of the Al1−xInxN layer assuming the growth of an indium depleted phase in the initial stage of growth.