Non-destructive characterization of extended crystalline defects in confined semiconductor device structures.
Non-destructive characterization of extended crystalline defects in confined semiconductor device structures.
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受限半导体器件结构中扩展晶体缺陷的无损表征。
DOI：
10.1039/c8nr00186c
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发表时间：
2018
期刊：
影响因子：
6.7
通讯作者：
M. Caymax
中科院分区：
文献类型：
--
作者：
A. Schulze;Libor Strakoš;T. Vystavěl;R. Loo;A. Pacco;N. Collaert;W. Vandervorst;M. Caymax
半导体异质结构是大多数纳米电子和光子器件的核心，例如先进晶体管、激光器、发光二极管、光调制器和光电探测器。然而，各个器件的性能和可靠性常常受到晶体缺陷的限制，这些晶体缺陷是由这些异质系统中存在的失配应变的塑性松弛引起的。迄今为止，精确且非破坏性地表征 3D 纳米级器件中此类缺陷的性质和分布仍然是一项关键的计量挑战。在本文中，我们证明电子通道衬度成像 (ECCI) 能够分析受限 3D 纳米结构中的单个位错和堆垛层错，从而满足上述要求。为此，我们使用扫描电子显微镜 (SEM) 在受控衍射条件下对测试样品反向散射的电子强度进行成像。与透射电子显微镜 (TEM) 分析相反，无需制备电子透明样品。这使得检测限显着降低（即可以评估的最低缺陷密度），因为我们的方法有利于分析大样本量，从而提供出色的统计数据。我们将该方法应用于通过选择性区域外延生长的 SiGe 纳米结构，以详细研究结构尺寸如何影响晶体缺陷的性质和分布。通过将我们的观察结果与 X 射线衍射、TEM 和化学缺陷蚀刻获得的结果进行比较，我们可以验证该方法的有效性。我们的研究结果坚定地表明，ECCI 必须被视为分析 3D 半导体异质结构晶体质量的首选方法，即使在低缺陷密度下也能具有出色的精度。因此，该技术有助于更好地理解纳米尺度的应变弛豫和缺陷形成机制，此外，还有助于下一代纳米电子和光子器件的开发和制造。
Semiconductor heterostructures are at the heart of most nanoelectronic and photonic devices such as advanced transistors, lasers, light emitting diodes, optical modulators and photo-detectors. However, the performance and reliability of the respective devices are often limited by the presence of crystalline defects which arise from plastic relaxation of misfit strain present in these heterogeneous systems. To date, characterizing the nature and distribution of such defects in 3D nanoscale devices precisely and non-destructively remains a critical metrology challenge. In this paper we demonstrate that electron channeling contrast imaging (ECCI) is capable of analyzing individual dislocations and stacking faults in confined 3D nanostructures, thereby fulfilling the aforementioned requirements. For this purpose we imaged the intensity of electrons backscattered from the sample under test under controlled diffraction conditions using a scanning electron microscope (SEM). In contrast to transmission electron microscopy (TEM) analysis, no electron transparent specimens need to be prepared. This enables a significant reduction of the detection limit (i.e. lowest defect density that can be assessed) as our approach facilitates the analysis of large sampling volumes, thereby providing excellent statistics. We applied the methodology to SiGe nanostructures grown by selective area epitaxy to study in detail how the nature and distribution of crystalline defects are affected by the dimensions of the structure. By comparing our observations with the results obtained using X-ray diffraction, TEM and chemical defect etching, we could verify the validity of the method. Our findings firmly establish that ECCI must be considered the method of choice for analyzing the crystalline quality of 3D semiconductor heterostructures with excellent precision even at low defect densities. As such, the technique aids in better understanding of strain relaxation and defect formation mechanisms at the nanoscale and, moreover, facilitates the development and fabrication of next generation nanoelectronic and photonic devices.
影响因子：
8.6
作者：
Naresh-Kumar, G.;Hourahine, B.;Trager-Cowan, C.
通讯作者：
Trager-Cowan, C.