PREFERENTIAL ORIENTATION GROWTH OF AlN THIN FILMS ON Si(111) SUBSTRATES BY PLASMA-ASSISTED MOLECULAR BEAM EPITAXY

This article reports the use of plasma-assisted molecular beam epitaxy (MBE) to grow AlN on Si(111) substrate at 850°C under UHV conditions for 15, 30, and 45 min. The films were characterized by high-resolution X-ray diffraction (HR-XRD) and micro-Raman spectroscopy. XRD measurement revealed that the AlN was epitaxially grown on Si(111). Micro-Raman result showed that all the allowed Raman modes of AlN and Si were clearly visible. Fourier transform infrared (FTIR) spectroscopy has been used to investigate the A1 (LO) and E1 (TO) modes with frequencies (890–899) cm-1 and (668–688) cm-1, respectively. The results are in good agreement with reported phonon frequencies of AlN grown on Si(111).