Stacking of freestanding membranes enables the formation of interfaces beyond what can be obtained with classical heteroepitaxy. In particular, twisted interfaces provide unique physical properties not existent in the corresponding individual layers. An ideal twist grain boundary yields an in-plane screw-dislocation network, assuming sufficiently strong interactions across the interface, for example, via covalent or ionic bonding. Hereby, the distance between dislocation lines, that is the length scale of the Moir…

The monolithic integration of III-V semiconductors with silicon (Si) is a critical step toward advancing optoelectronic and photonic devices. In this work, we present GaAs nanoheteroepitaxy (NHE) on Si nanotips using gas-source molecular beam epitaxy (GS-MBE). We discuss the selective growth of fully relaxed GaAs nanoislands on complementary metal oxide semiconductor (CMOS)-compatible Si(001) nanotip wafers. Nanotip wafers were fabricated using a state-of-the-art 0.13 μm SiGe Bipolar CMOS pilot line on 200 mm wafe…

<title>Abstract</title> β-Ga₂O₃thin films (~ 83 nm) were grown on β-(AlₓGa_1-x)₂O₃ (x = 0.1, 0.15, 0.2) (100) substrates via metal-organic vapor phase epitaxy (MOVPE) and characterized by high resolution x-ray diffraction (HR-XRD), atomic force microscopy (AFM) and spectroscopic ellipsometry (SE). HR-XRD<bold> confirmed the coherent epitaxial growth of </bold>β-Ga₂O₃<bold> thin films, with the strain state exhibiting a direct dependence on the alumi…

The luminescence properties of two co-doped ZnSe:(Cr, Fe) single crystals, grown by the Bridgman method, have been studied using photoluminescence techniques. Structural characterization by high-resolution X-ray diffraction (HR-XRD), electron paramagnetic resonance (EPR) and scanning electron microscopy (SEM) has revealed that the samples differ in terms of dopant concentration and intrinsic native defects. Analysis of the VIS and near-IR photoluminescence spectra, based on the modified crystal field theory and DF…

In this work, we present the monolithic integration of GaAsP and GaInP islands, selectively grown on a CMOS-compatible Si nanotip wafer using gas-source molecular beam epitaxy via a nanoheteroepitaxy approach. These alloys span a wide electronic bandgap range, from infrared to green; making them highly attractive for optoelectronic applications in silicon photonics. In addition, the nanoheteroepitaxy method enables the growth of various alloy combinations without the need for a lattice-matched substrate. We discus…