Room temperature photoluminescence from the amorphous Si structure generated under keV Ar-ion- induced surface rippling condition

We observe room temperature (RT) visible and infrared (IR) photoluminescence (PL) bands peaked around 680 and 1020 nm, respectively, from a silicon (Si) surface amorphized and patterned with ripples by 60 keV Ar+ bombardment at 60 degrees angle of ion incidence. However, the Si surface amorphized but not patterned under normal bombardment (0 degrees angle of ion incidence) condition shows a drastic reduction in the intensity of the visible PL along with the complete suppression of IR emission. The present work demonstrates that Ar ion irradiation at rippling condition may yield a porouslike light emitting amorphous silicon (a-Si) nanostructure.