Structure and properties of ion-beam-modified (6H) silicon carbide
Structure and properties of ion-beam-modified (6H) silicon carbide
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DOI：
10.1016/s0921-5093(98)00710-2
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发表时间：
1998-09-30
期刊：
影响因子：
6.4
通讯作者：
Hess, NJ
中科院分区：
文献类型：
--
作者：
Weber, WJ;Wang, LM;Hess, NJ
研究了离子束辐照下（6 H）α-SiC单晶的晶-非晶相变与辐照温度的关系。在20 ~ 475 K温度范围内，用0.8 MeV Ne+、1.0 MeV Ar+和1.5 MeV Xe+离子辐照样品，用透射电子显微镜原位跟踪了非晶态的演变。在20 K下，在α-SiC中完全非晶化的阈值位移剂量为0.30 dpa（损伤能量= 15 eV原子（-1））。完全非晶化的剂量随着温度的升高而增加，这是由于同时的恢复过程可以用单激活过程来充分建模。临界温度，在此之上不发生非晶化，增加颗粒质量和饱和在约500 K。具有[0001]取向的α-SiC单晶也在300 K下用360 keV Ar 2+离子以25度的入射角在1至8 Ar 2+离子nm（-2）的能量密度范围内辐照。在这些样品中的损伤积累已被其特征在于非原位卢瑟福背散射光谱沟道（RBS/C）沿着[0001]方向，拉曼光谱，横截面透射电子显微镜（XTEM），和机械微探针测量。(C)1998年Elsevier Science S.A. All rights reserved.
The ion-beam-induced crystalline-to-amorphous phase transition in single crystal (6H) alpha-SiC has been studied as a function of irradiation temperature. The evolution of the amorphous state has been followed in situ by transmission electron microscopy in specimens irradiated with 0.8 MeV Ne+, 1.0 MeV Ar+, and 1.5 MeV Xe+ ions over the temperature range from 20 to 475 K. The threshold displacement dose for complete amorphization in alpha-SiC at 20 K is 0.30 dpa (damage energy = 15 eV atom(-1)). The dose for complete amorphization increases with temperature due to simultaneous recovery processes that can be adequately modeled in terms of a single-activated process. The critical temperature, above which amorphization does not occur, increases with particle mass and saturates at about 500 K. Single crystals of alpha-SiC with [0001] orientation have also been irradiated at 300 K with 360 keV Ar2+ ions at an incident angle of 25 degrees over fluences ranging from 1 to 8 Ar2+ ions nm(-2). The damage accumulation in these samples has been characterized ex situ by Rutherford backscattering spectrometry-channeling (RBS/C) along the [0001] direction, Raman spectroscopy, cross-sectional transmission electron microscopy (XTEM), and mechanical microprobe measurements. (C) 1998 Elsevier Science S.A. All rights reserved.