Dubrovskii Vladimir G
Faculty of Physics, St. Petersburg State University, Universitetskaya Emb. 13B, 199034 St. Petersburg, Russia.
Nanomaterials (Basel). 2023 Apr 1;13(7):1253. doi: 10.3390/nano13071253.
Catalyst-free growth of III-V and III-nitride nanowires (NWs) by the self-induced nucleation mechanism or selective area growth (SAG) on different substrates, including Si, show great promise for monolithic integration of III-V optoelectronics with Si electronic platform. The morphological design of NW ensembles requires advanced growth modeling, which is much less developed for catalyst-free NWs compared to vapor-liquid-solid (VLS) NWs of the same materials. Herein, we present an empirical approach for modeling simultaneous axial and radial growths of untapered catalyst-free III-V NWs and compare it to the rigorous approach based on the stationary diffusion equations for different populations of group III adatoms. We study in detail the step flow occurring simultaneously on the NW sidewalls and top and derive the general laws governing the evolution of NW length and radius versus the growth parameters. The rigorous approach is reduced to the empirical equations in particular cases. A good correlation of the model with the data on the growth kinetics of SAG GaAs NWs and self-induced GaN NWs obtained by different epitaxy techniques is demonstrated. Overall, the developed theory provides a basis for the growth modeling of catalyst-free NWs and can be further extended to more complex NW morphologies.
通过自诱导成核机制或在包括硅在内的不同衬底上进行选择性区域生长（SAG），实现III-V族和III族氮化物纳米线（NWs）的无催化剂生长，这为III-V族光电器件与硅电子平台的单片集成展现出了巨大潜力。纳米线阵列的形态设计需要先进的生长模型，与相同材料的气-液-固（VLS）纳米线相比，无催化剂纳米线的生长模型发展程度要低得多。在此，我们提出一种经验方法来模拟无锥度无催化剂III-V族纳米线的轴向和径向同时生长，并将其与基于不同III族吸附原子群体的稳态扩散方程的严格方法进行比较。我们详细研究了纳米线侧壁和顶部同时发生的台阶流，并推导了控制纳米线长度和半径随生长参数变化的一般规律。在特定情况下，严格方法简化为经验方程。结果表明，该模型与通过不同外延技术获得的SAG GaAs纳米线和自诱导GaN纳米线生长动力学数据具有良好的相关性。总体而言，所发展的理论为无催化剂纳米线的生长建模提供了基础，并且可以进一步扩展到更复杂的纳米线形态。
