A metal/HfAlO/Si light emitting diode with Ge nanocrystals embedded in HfAlO has the visible light emission (610 nm) and the infrared emission (760 nm). The image and Ge content are measured by the transmission electron microscopy and Raman spectroscopy. The photoluminescence of Ge nanocrystals embedded in HfAlO has a peak wavelength at 700 nm, while the peak wavelength at 725 nm is observed for Ge nanocrystals embedded in HfO2. The difference of it may be due to the larger band gap of HfAlO as compared to HfO2. (C) 2009 American Vacuum Society. [DOI: 10.1116/1.3025844]