We propose a new growth scheme of digitally alloyed modulated precursor flow epitaxial growth (DA-MPEG) using metalorganic and hydride precursors for the growth of AlxGa1-xN layers with high-Al content at relatively low temperatures. The growth of high-quality, high-Al content AlxGa1-xN layers (x(Al) > 50%) that are composed of AlN and AlyGa1-yN monolayers on AlN/sapphire template/substrates by DA-MPEG was demonstrated. The overall composition of the ternary AlxGa1-xN material by DA-MPEG can be controlled continuously by adjusting the Column III mole fraction of the atomic AlyGa1-yN sublayer. X-ray diffraction and optical transmittance results show that the AlGaN materials have good crystalline quality. The surface morphology of DA-MPEG AlGaN samples measured by atomic force microscopy are comparable to high-temperature-grown AlGaN and are free from surface features such as nano-pits. (C) 2009 Elsevier B.V. All rights reserved.