Wurtzite GaN films bombarded with 40keV C ions to high doses (5×1017 and 1×1018cm−2) are studied by a combination of Rutherford backscattering/channeling spectrometry, transmission electron microscopy, and soft x-ray absorption spectroscopy. Results show that, contrary to other ion species, implanted C forms nitrilelike carbon-nitride bonds (CN) and suppresses ion-beam-induced material decomposition involving the formation and agglomeration of ≳5-nm-large N2 gas bubbles.

Although Er-doped Ge nanomaterials are attractive for photonic applications, very little is known about the basic properties of Er in Ge. Here, the authors study the annealing behavior of Ge implanted with keV Er ions to doses resulting in Շ1 at. % of Er. Large redistribution of Er, with segregation at the amorphous/crystalline interface, starts at տ500°C, while lower temperatures are required for material recrystallization. However, even at 400°C, Er forms precipitates. The concentration of Er trapped in the bulk after recrystallization decreases with increasing temperature but is independent of the initial bulk Er concentration for the range of ion doses studied here.