Cuprous oxide (Cu2O) films from 25 nm to 1500 nm were electrodeposited on n-Si(100) and Ni/n-Si(100) substrates from aqueous solution at room temperature. X-ray diffraction and transmission electron microscopy imaging show that the Cu2O structure and morphology is strongly affected by the substrate choice, with V shape and U shape columnar growth on n-Si(100) and Ni/n-Si(100), respectively. Atomic force microscopy reveals the presence of rounded grains at the surface in both cases. Anomalous and normal roughening are observed in films grown on n-Si and Ni, respectively, but estimates of scaling exponents are not conclusive. On the other hand, the distributions of local heights, roughness, and extremal heights show good agreement with those of the fourth order linear stochastic equation of Mullins and Herring (MH). Thus, surface dynamics in both systems is dominated by diffusion of adsorbed molecules, with no large scale effect of possible inhomogeneities in mass flux from the solution or in reaction and adsorption rates. In growth on n-Si substrates, the noise amplitude of the MH equation increases in time as t^{0.8}, while the coefficient of the curvature-related term is time-independent. Step edge energy barriers restrict the mass flux across grain boundaries, thus a broad size distribution of initial grains leads to coarsening of the larger ones. This explains their V shape in the thickest films and establishes a connection with the anomalous roughening. These effects are reduced in films grown on Ni/n-Si, which initially have much larger grains with narrower size distributions and, consequently, smaller fluctuations in coarse grained growth rates.
Modeling electrodeposition of thin films with compact, dendritic, and random morphologies
Instituto de Física, Universidade Federal Fluminense（弗鲁米嫩塞联邦大学物理研究所）；Chimie ParisTech - CNRS, Institut de Recherche de Chimie Paris（巴黎高等化学学院-法国国家科学研究中心巴黎化学研究所）；Departamento de Física, Universidade Federal de Viçosa（维索萨联邦大学物理系）
Cross-hatch strain effects on SiGe quantum dots for qubit variability estimation
Sandia National Laboratories（桑迪亚国家实验室）；Baylor University（贝勒大学）；University of Milano-Bicocca（米兰比可卡大学）；Eurofins EAG Materials Science（Eurofins EAG材料科学）；University of Arkansas at Pine Bluff（阿肯色州立大学平布拉夫分校）；Lawrence Semiconductor Research Laboratory, Inc.（劳伦斯半导体研究实验室有限公司）；Purdue University（普渡大学）
