X-ray diffractometric study of the influence of a buffer layer on the microstructure of molecular-beam epitaxial InN layers of different thicknesses

Thin layers of InN are grown by molecular beam epitaxy on (0001) sapphire s ubstrates. The influence of thin (15 nm) InN buffer layers and their temper ature treatment on the structural quality of the grown layers is investigat ed by double-crystal and triple-crystal x-ray diffractometry. It is reveale d that the preliminary high-temperature (900 degreesC) annealing of the buf fer layer leads to a notable improvement in the quality of the layers grown on this buffer. The densities of vertical screw and vertical edge dislocat ions decrease (to 1.9 x10(8) cm(-2) and 1.3 x 10 cm(-2), respectively) with an increase in the distance from the interface (by similar to1 mum). (C) 2 001 MAIK "Nauka/Interperiodica".