Optical properties of manganese doped amorphous and crystalline aluminum nitride films

摘要

An aluminum nitride (AlN) film deposited on silicon (100) was used as the substrate for growing manganese (Mn) doped AlN film by metal organic chemical vapor deposition (MOVCD). The (15.78μm) under layer of AlN was grown at 615°C at a pressure of 10{sup}(-4) Torr. The (2.1 μm) top layer of Mn-AlN was grown at the same temperature and pressure but doped with pulse valve introduction of the manganese decacarbonyl (100 ms on, 100 ms off). The film was then characterized ex situ with IR reflectance microscopy, X-ray diffraction, scanning electron microscopy imaging, cathodoluminescence, and X-ray fluorescence. The IR reflectance measurements showed a strong (Al) LO mode for AlN at 920 cm{sup}(-1)and 900 cm{sup}(-1) with a shoulder at 849 cm{sup}(-1). X-ray Diffraction yielded three diffraction peaks at a 20 position of 33, 36 and 38 degrees corresponding to 100, 002, and 101 lattice planes respectively. Cathodoluminescence results show strong visible emitted light from incorporated manganese. The relative percentage of manganese to aluminum was below the detection limit (0.01％) of the X-ray fluorescence spectrometer. Amorphous Mn doped AlN films have also been grown using a low temperature atomically abrupt sputter epitaxial system. The amorphous Mn doped AlN showed no cathodoluminescence.