Nanonet Formation by Constitutional Supercooling of Pulsed Laser Annealed, Mn-Implanted Germanium
Nanonet Formation by Constitutional Supercooling of Pulsed Laser Annealed, Mn-Implanted Germanium
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DOI：
10.1007/978-3-319-03131-6_2
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发表时间：
2014
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影响因子：
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通讯作者：
D. Bürger;Shengqiang Zhou;Marcel Höwler;X. Ou;G. Kovács;H. Reuther;A. Mücklich;W. Skorupa;H. Schmidt
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文献类型：
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作者：
D. Bürger;Shengqiang Zhou;Marcel Höwler;X. Ou;G. Kovács;H. Reuther;A. Mücklich;W. Skorupa;H. Schmidt
本章节介绍脉冲激光退火的有趣方面。在此过程中，激光脉冲将热量吸收到半导体或金属的近表面区域。如果能量密度足够高，系统可能会在表面附近熔化。由于温度梯度大，非常快的再结晶可能会带来新的物理材料特性。在这里，我们介绍了在锗中形成富锰纳米网的有趣方面。详细解释了重要的物理现象。该材料是通过脉冲持续时间为 300 ns 的 Mn 注入 Ge 晶圆进行脉冲激光退火制成的。由于再结晶过程中的偏析不稳定性，Mn 在液固界面偏析，并且约 40 nm 厚的 Ge:Mn 表面层富含 Mn。透射电子显微镜平面图图像揭示了蚀刻顶部 10 nm 表面层后渗透的富锰纳米网。在高达 30 K 的温度下观察到滞后反常霍尔效应，但在蚀刻掉 40 nm 厚的富锰 Ge:Mn 层后该效应消失。纳米网似乎支持磁化强度和磁滞霍尔电阻之间的相关性。 Ge:Mn 纳米网的线或顶点中的固有电荷载流子散射可能导致观察到的异常霍尔效应。在展望中，揭示了过冷锰注入硅的纳米网形成。
This subchapter presents interesting aspects of pulsed laser annealing. During this process, a laser pulse incorporates heat in the near surface region of a semiconductor or a metal. If the energy density is high enough, the system may melt near the surface. Because of the large temperature gradient, a very fast recrystallization may lead to novel physical material properties. Here we present interesting aspects of the formation of a Mn-rich nanonet in germanium. Important physical phenomena are explained in detail. The material has been fabricated by pulsed laser annealing of Mn implanted Ge wafers with a pulse duration of 300 ns. Due to a segregation instability during recrystallization, Mn segregates at the liquid-solid interface and an approximately 40 nm thick Ge:Mn surface layer is strongly enriched with Mn. Transmission electron microscopy plan-view images reveal a percolating Mn-rich nanonet after etching the top 10 nm surface layer. Hysteretic anomalous Hall effect has been observed up to 30 K, but it vanishes after etching away the 40 nm thick Mn-rich Ge:Mn layer. The nanonet seems to support the correlation between magnetization and hysteretic Hall resistance. Intrinsic charge carrier scattering in the threads or vertices of the Ge:Mn nanonet may lead to the observed anomalous Hall effect. In the outlook the nanonet formation is revealed for supercooled Mn-implanted Si.