Optical transient in ion irradiated silicon carbide

The optical properties of silicon carbide single crystals irradiated with a 100 keV N+ ion beam have been monitored by in situ transmittance and reflectance measurements at a wavelength of 633 nm. The absorption coefficient of the damaged samples shows a fast increase with ion fluence over four orders of magnitude going from 5 cm(-1) (crystal) to 7.8 x 10(4) cm(-1) (amorphous). When the ion beam is stopped the transmittance starts to increase and it reaches a steady state value after similar to 400 s. The absolute reduction of the absorption is proportional to the amorphous fraction and it is maximum in the amorphous material. Similar transient optical properties were observed for other implanted ions independently of the species.