The influence of high energy krypton ion irradiation on optical and electronic properties of diamond

Natural diamond irradiated by krypton ions with 210 or 247 MeV energy withi n a dose range of 5x10(10)-1.2x10(14) cm(-2) has been investigated by optic al absorption, photoluminescence and electric methods. The main features of the absorption spectra of the irradiated diamond are a GR1-band and a cont inuous absorption band in the ultraviolet part of a spectrum. 800 degreesC annealing causes the GR1 band disappearance, but the continuous absorption band in the ultraviolet part of the spectrum decreases up to 1400 degreesC. The changes at the dose of 10(13) cm(-2) in absorption intensity of these bands can be attributed to overlapping of ion tracks. The tracks of ions gi ve rise to deep trap levels in the forbidden gap of diamond, which are impo ssible to anneal even at 1450 degreesC. (C) 2001 Elsevier Science Ltd. All right reserved.