Fabrication and photoluminescence characteristics of In 2 O 3 nanohillocks

Uniformly distributed polycrystalline indium nanohillocks are synthesized on silicon substrates with Au catalyst by using the radio frequency magnetic sputtering technique. The results show that the Au catalyst plays a key role in the formation of indium nanohillocks. After thermally oxidizing the indium nanohillocks at 500 °C in air for 5 h, the indium nanohillocks totally transform into In 2 O 3 nanohillocks. The energy-dispersive X-ray spectroscopy result indicates that many oxygen vacancies and oxygen—indium vacancy pairs exist in the In 2 O 3 nanohillocks. Photoluminescence spectra under an Ne laser excitation at 280 nm show broad emissions at 420 nm and 470 nm with a shoulder at 450 nm related to oxygen vacancies and oxygen—indium vacancies at room temperature.