【摘要】 对6H-SiC单晶进行中子辐照(中子总剂量为2.85×1020 n/cm~2)后对其进行200~1 700℃的等时退火处理,利用X线衍射技术(XRD)观察和分析中子辐照对样品造成的损伤及其回复规律.通过研究(0001)晶面衍射峰的峰形和峰位置发现,等时退火处理后,辐照缺陷逐渐消失,晶体衍射峰的半高宽在200~600℃回复明显,在600~1 400℃没有明显变化,但在1 400℃之后又开始明显减小,最后接近辐照前的数值.而晶面间距d在200~1 400℃时持续减小,之后又随退火温度的升高而变大,最后接近辐照前的数值.通过对辐照损伤回复规律的分析认为,中子辐照使样品内部出现了大量点缺陷和线缺陷,而这些缺陷大多可以通过高温退火消除.更多还原

【Abstract】 The 6 H-SiC single crystals was irradiated with a total neutron dose of 2.85×1020 n/cm~2,then were treated with isochronal annealing from 200℃to 1 700℃,and the irradiation-damage-recovery law were observed and analyzed by X-ray-diffraction(XRD).By the observing the shape and position of the diffraction peak of(0001)crystal plane after isochronal annealing,we found that the full width half maximum(FWHM)of diffraction peak decreased obviously from 200℃to 600℃,and it has no obvious change when the annealing temperature varier from 600℃to 1 400℃.However,the FWHM is close to that of the pre-irradiation sample when the temperature is higher than 1 400℃.Meanwhile,the interplanar distance decreases continuously from 200℃to 1 400℃,then increases with the increase of annealing temperature,and finally approaches that of pre-irradiation sample.It is believed that a large number of point defects and line defect are produced within the sample by neutron irradiation.Hawever most of these defects can be eliminated by high temperature annealing.更多还原