论文标题
介孔图案硅上微晶的缺陷自由应变松弛
Defect free strain relaxation of microcrystals on mesoporous patterned silicon
论文作者
论文摘要
一个完美的衬底将允许在硅（SI）基板上进行高质量的半导体材料（例如GE和III-V）的整体整合，从而在良好的低成本SI技术平台上具有新的功能。在这里，我们展示了一个符合条件的SI基材，允许晶格不匹配的材料的无缺陷外延生长。该方法基于SI底物的深层模式，形成微米尺度的支柱和随后的电化学孔隙化。通过X射线衍射，透射电子显微镜和蚀刻点计数对外延GE结晶质量的研究表明，无缺陷的微晶的完全弹性松弛。实现无脱位的无异性膜状的实现取决于多孔微柱的弹性变形之间的相互作用，这是通过GE和Si之间的晶格不匹配在压力下的弹性变形，以及GE将GE扩散到介孔图案化的底物中，使GE/SI接口处的不匹配应变减弱。
A perfectly compliant substrate would allow the monolithic integration of high-quality semiconductor materials such as Ge and III-V on Silicon (Si) substrate, enabling novel functionalities on the well-established low-cost Si technology platform. Here, we demonstrate a compliant Si substrate allowing defect-free epitaxial growth of lattice mismatched materials. The method is based on the deep patterning of the Si substrate to form micrometer-scale pillars and subsequent electrochemical porosification. The investigation of the epitaxial Ge crystalline quality by X-ray diffraction, transmission electron microscopy and etch-pits counting demonstrates the full elastic relaxation of defect-free microcrystals. The achievement of dislocation free heteroepitaxy relies on the interplay between elastic deformation of the porous micropillars, set under stress by the lattice mismatch between Ge and Si, and on the diffusion of Ge into the mesoporous patterned substrate attenuating the mismatch strain at the Ge/Si interface.
