Related papers: Low cost Ge/Si virtual substrate through dislocati…
A great deal of interest is directed nowadays towards the development of innovative technologies in the field of quantum information and quantum computing, with emphasis on obtaining reliable qubits as building blocks. The realization of…
While vertical GaN-on-silicon architectures promise a transformative leap in cost-effective power electronics and high-resolution micro-LEDs, their deployment remains bottlenecked by the high electrical resistance of conventional epitaxial…
We describe epitaxial Ge/Si multilayers with cross-plane thermal conductivities which can be systematically reduced to exceptionally low values, as compared both with bulk and thin-film SiGe alloys of the same average concentration, by…
We performed classical molecular dynamics simulations to investigate, from an atomistic point of view, the formation of dislocations during the epitaxial growth of Ge on Si. We show that simulations at 900 and 1000 K with deposition rates…
Topological insulators (TIs) like Bi$_2$Se$_3$ are a class of material with topologically protected surface states in which spin-momentum locking may enable spin-polarized and defect-tolerant transport. In this work, we achieved the…
The strain-relaxation mechanism of a set of Si$_{0.6}$Ge$_{0.4}$ linearly graded buffers (LGBs), grown following different temperature profiles, has been investigated by means of defect-etching and variable-temperature high-resolution X-ray…
We account for lateral orderings of III-V nanostructures resulting from a GaAs/InAs/InGaAs/GaAs sequence grown on GaAs by metallorganic vapour phase epitaxy at two different temperatures. For both samples, the ordering is induced by the…
A tandem GaAsP/SiGe solar cell has been developed employing group-IV reverse buffer layers grown on silicon substrates with a subsurface porous layer. Reverse buffer layers facilitate a reduction in the threading dislocation density with…
We first report a detailed transmission electron microscopy study of dislocation networks (DNs) formed at shallowly buried interfaces obtained by bonding two GaAs crystals between which we establish in a controlled manner a twist and a tilt…
We report on a process that enables the removal of II-VI semiconductor epilayers from their GaAs growth substrate and their subsequent transfer to arbitrary host environments. The technique combines mechanical lapping and layer selective…
We analyze the solution of the Schr\"odinger equation arising in the treatment of a geometric model introduced to explain the origin of the observed shallow levels in semiconductors threaded by a dislocation density. We show (contrary to…
Germanium-Tin (GeSn) alloys have emerged as a promising material for future optoelectronics, energy harvesting and nanoelectronics owing to their direct bandgap and compatibility with existing Si-based electronics. Yet, their metastability…
Multijunction solar cells are usually grown on Ge substrates. This implies several disadvantages that hinder the performance of the whole multijunction and limit their possible applications. The drawbacks caused by the substrate are:…
Ge/SiGe multi-quantum well heterostructures are highly sought-after for silicon-integrated optoelectronic devices operating in the broad range of the electromagnetic spectrum covering infrared to terahertz wavelengths. However, the…
Discrete dislocation dynamics (DDD) is a widely employed computational method to study plasticity at the mesoscale that connects the motion of dislocation lines to the macroscopic response of crystalline materials. However, the…
The method of software analysis of high-resolution TEM images using the peak pairs algorithm in combination with Raman spectroscopy was employed to study lattice deformations in Ge/Si(001) structures with low-temperature Ge quantum dots. It…
Low temperature epitaxial breakdown of inhomogeneously strained Si capping layers is investigated. By growing Si films on coherently strained GeSi quantum dot surfaces, we differentiate effects of surface roughness, strain, and growth…
Two types of nucleation layers (NLs), including in-situ low-temperature grown GaN (LT-GaN) and ex-situ sputtered physical vapor deposition AlN (PVD-AlN), are applied on cone-shaped nanoscale patterned sapphire substrate (NPSS). The initial…
Si/Ge heteroepitaxial dots under tensile strain are grown on nanostructured Ge substrates produced by high-temperature flash heating exploiting the spontaneous faceting of the Ge(001) surface close to the onset of surface melting. A very…
The domain structures and dislocations in epitaxial thin films of La0.7Ca0.3MnO3 grown on SrTiO3 substrates by pulsed laser deposition were investigated using Bragg-contrast diffraction and high-resolution transmission electron microscopy.…