Growth and Characterization of In-rich In_xAl_(1-x)N Alloys on Si(111) Substrate by RF-MOMBE

摘要

InN-based materials are a potential material for various devices such as infrared light emitters and high efficiency optoelectronic device because of it is high mobility and narrow band gap of 0.6-0.8 eV. However, the InN is difficult to grow high-crystalline-quality InN owing to its low dissociation temperature and the lack of lattice-matched substrates. In-rich InAlN films were grown directly on Si(111) substrate by RF-MOMBE without any buffer layer. InAlN films were grown at various substrate temperatures in the range of 460-540℃ with TMIn/TMAl ～ 3.3. Structural properties of InAlN ternary alloys were investigated with x-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM). The XRD results indicated that In-rich InAlN films grown with the 460℃ has the smallest full width at half maximum value of 108 arcmin for (0002) X-ray rocking curve (XRC). Also, ross-sectional TEM from InAlN grown on Si(111) at 460℃ shows that the epitaxial film is in direct contact with orientation relationship of InAlN (0002)_(InAlN)//(111)_(Si), 2110_(InAlN)//110_(Si),0110InAlN//112_(Si).