Intense Red Catho- and Photoluminescence from 200 nm Thick Samarium Doped Amorphous AlN Thin Films
1 Department of Physics and Astronomy, Ball State University, Muncie, IN, 47306, USA
2 Department of Physics, State University of New York at Buffalo, Buffalo, NY, 14260, USA
Nanoscale Research Letters 2009, 4:748-752 doi:10.1007/s11671-009-9309-7Published: 25 April 2009
Samarium (Sm) doped aluminum nitride (AlN) thin films are deposited on silicon (100) substrates at 77 K by rf magnetron sputtering method. Thick films of 200 nm are grown at 100–200 watts RF power and 5–8 m Torr nitrogen, using a metal target of Al with Sm. X-ray diffraction results show that films are amorphous. Cathodoluminescence (CL) studies are performed and four peaks are observed in Sm at 564, 600, 648, and 707 nm as a result of4G5/2 → 6H5/2,4G5/2 → 6H7/2,4G5/2 → 6H9/2, and4G5/2 → 6H11/2transitions. Photoluminescence (PL) provides dominant peaks at 600 and 707 nm while CL gives the intense peaks at 600 nm and 648 nm, respectively. Films are thermally activated at 1,200 K for half an hour in a nitrogen atmosphere. Thermal activation enhances the intensity of luminescence.