单晶YSZ的Xe^+离子辐照效应研究

Study of Xe^+-irradiation effect on yttria-stabilized zirconia single crystals

200keVXe+离子辐照使单晶YSZ由无色透明变成紫色透明,结果表明,能量为200keV,注量为1×1017cm-2的Xe+离子辐照YSZ单晶产生的损伤高达350dpa,在损伤区产生高密度的缺陷,但仍然没有发生非晶化转变。吸收光谱测试结果表明,产生吸收带的注量阈值大约为1016cm-2。注量为1×1016cm-2和1×1017cm-2的样品,吸收带峰值分别位于522nm和497nm。光吸收带可能与Zr阳离子最近邻的氧空位捕获电子形成的F型色心和Y阳离子近邻的氧离子捕获空穴形成的V型色心有关。

A transparent yttriastabilized zirconia (YSZ) single crystal becomes purple after 200keV Xe+irradiation. Calculation of TRIM 96 shows that 200keV Xe+ ions cause peak displacement levels of ～350dpa (displacement per atom) at the depth of 30nm in a YSZ single crystal at a dose of 1×1017cm-2, and crosssectional TEM images and diffraction pattern show that there is no amorphization. Optical absorption measurements show that a broad absorption band appears at a dose of 1×1016cm-2. For the 1×1016cm-2 and 1×1017cm-2 Xe+irradiated crystals, the absorption bands are centered at 522nm and 497nm, respectively. The bands are assigned to electrons trapped at oxygen vacancies nearest to Zr cations (Ftype centers) and to oxygen ions with trap holes adjacent to yttria cations (Vtype centers).