Extended x-ray absorption fine structure study of porous GaSb formed by ion implantation
Extended x-ray absorption fine structure study of porous GaSb formed by ion implantation
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离子注入多孔GaSb的扩展X射线吸收精细结构研究
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
M. Ridgway
中科院分区：
文献类型：
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作者：
P. Kluth;S. Kluth;B. Johannessen;C. Glover;G. Foran;M. Ridgway
用Ga离子注入GaSb晶体衬底，在室温和−温度下制备了多孔GaSb，用扫描电子显微镜对其形貌进行了表征，用扩展X射线吸收精细结构谱测定了其原子结构。低注量下的室温注入导致了∼20 nm空穴的形成，但材料仍保持结晶状态。较高的注量使微观结构演变成直径15 nm的无定形GaSb棒∼的网络。相比之下，在−180°C下注入会产生较大的拉长空洞，但没有棒。当暴露在空气中时，多孔材料的表面很容易被氧化，产生Ga2O_3和金属Sb沉淀，后者是不稳定的Sb_2O_3还原的结果。我们考虑并讨论了在同时发生的晶态到非晶态和连续孔道转变过程中可能起作用的原子尺度机制。
Porous GaSb has been formed by Ga ion implantation into crystalline GaSb substrates at either room temperature or −180 °C. The morphology has been characterized using scanning electron microscopy and the atomic structure was determined using extended x-ray absorption fine structure spectroscopy. Room-temperature implantation at low fluences leads to the formation of ∼20-nm voids though the material remains crystalline. Higher fluences cause the microstructure to evolve into a network of amorphous GaSb rods ∼15 nm in diameter. In contrast, implantation at −180 °C generates large, elongated voids but no rods. Upon exposure to air, the surface of the porous material is readily oxidized yielding Ga2O3 and metallic Sb precipitates, the latter resulting from the reduction of unstable Sb2O3. We consider and discuss the atomic-scale mechanisms potentially operative during the concurrent crystalline-to-amorphous and continuous-to-porous transformations.