Benter Sandra, Jönsson Adam, Johansson Jonas, Zhu Lin, Golias Evangelos, Wernersson Lars-Erik, Mikkelsen Anders
Department of Physics, Lund University, Box 118, Lund, 22100, Sweden.
NanoLund Center for Nanoscience, Lund University, Box 118, Lund, 22100, Sweden.
Nat Commun. 2023 Jul 27;14(1):4541. doi: 10.1038/s41467-023-40157-5.
Local geometric control of basic synthesis parameters, such as elemental composition, is important for bottom-up synthesis and top-down device definition on-chip but remains a significant challenge. Here, we propose to use lithographically defined metal stacks for regulating the surface concentrations of freely diffusing synthesis elements on compound semiconductors. This is demonstrated by geometric control of Indium droplet formation on Indium Arsenide surfaces, an important consequence of incongruent evaporation. Lithographic defined Aluminium/Palladium metal patterns induce well-defined droplet-free zones during annealing up to 600 °C, while the metal patterns retain their lateral geometry. Compositional and structural analysis is performed, as well as theoretical modelling. The Pd acts as a sink for free In atoms, lowering their surface concentration locally and inhibiting droplet formation. Al acts as a diffusion barrier altering Pd's efficiency. The behaviour depends only on a few basic assumptions and should be applicable to lithography-epitaxial manufacturing processes of compound semiconductors in general.
对基本合成参数（如元素组成）进行局部几何控制，对于自下而上的合成以及芯片上自上而下的器件定义而言至关重要，但仍然是一项重大挑战。在此，我们提议使用光刻定义的金属堆栈来调节化合物半导体上自由扩散的合成元素的表面浓度。这通过对砷化铟表面铟液滴形成的几何控制得到了证明，这是不一致蒸发的一个重要结果。光刻定义的铝/钯金属图案在高达600°C的退火过程中会诱导出明确的无液滴区域，同时金属图案保持其横向几何形状。进行了成分和结构分析以及理论建模。钯充当自由铟原子的汇，局部降低其表面浓度并抑制液滴形成。铝充当扩散阻挡层，改变钯的效率。这种行为仅取决于几个基本假设，并且一般应适用于化合物半导体的光刻外延制造工艺。
