Wafer-scale epitaxial growth of AlN (0001) on heteroepitaxial diamond (111)

Wurtzite-type aluminum nitride (AlN) films were deposited by magnetron sputtering epitaxy (MSE) on wafer-scale diamond layers, which in turn were grown heteroepitaxially by plasma-enhanced chemical vapor deposition applying bias-enhanced nucleation on an Ir seed layer. The seed was fabricated on Si (111) wafers with an yttria-stabilized zirconia buffer layer by MSE. Analysis by x-ray diffraction has confirmed fully epitaxial growth throughout the entire stack. Due to diamond's high thermal conductivity, which makes it an effective heat sink, this stack constitutes an important step toward monolithically integrated high-efficiency III-nitride-diamond power electronics.