Growth and Characterization of GaAs Epitaxial Thin Films on van der Waals Surfaces

9414298在这项提案中，我们概述了一项研究计划，以研究新的砷化镓结构的生长和表征。这个项目的动机源于我们正在进行的研究工作，即开发新的处理路线来生长异质结构，而不考虑它们的晶格匹配要求。在这项工作中，我们开发了一种称为范德华外延(VDWE)的生长方法。VDWE是结晶学二维(2D)层状材料的外延生长，其各层通过van der Waals力保持在一起，并且表面不包含不满意的共价键。我们在过去已经证明，这些范德华材料可以在包括GaAs、Al_2O_3和CaF_2在内的各种三维(3D)材料上外延生长。如果能够在这种范德华表面上生长出GaAs层，就有可能有效地使晶格常数不同的两种3D材料之间的界面解耦，从而调节晶格失配。由于界面上的范德华作用力很弱，也可以去除(或剥离)外延层，以表征大面积薄膜和进一步处理去耦合异质结构器件。***

9414298 Ohuchi In this proposal we outline a research program to investigate the growth and characterization of new GaAs based structures. the motivation of this program originated from our on-going research effort to develop novel processing routes for growing heterostructures without regard to their lattice matching requirement. In this effort, we have developed a growth method called van der Waals epitaxy (VDWE). VDWE is the epitaxial growth of crystallographically two-dimensional (2D) layered materials, of which layers are held together by van der Waals forces, and contain no unsatisfied covalent bonds at the surface. We have demonstrated in the past that these van der Waals materials can be grown epitaxially on a wide range of three-dimensional (3D) materials including GaAs, A12O3 and CaF2. If GaAs Layers could then be grown on top of this van der Waals surface, it would be possible to effectively decouple the interface between the two 3D materials with dissimilar lattice constants and thereby accommodate the lattice mismatch. Due to the weak van der Waals forces across the interface, it is also possible to remove (or lift-off) the epitaxial layers for both characterizing broad area thin films and further processing of decoupled heterostructure devices. ***