First results of the novel BOSCO (“BO th Sides CO llecting and CO ntacted”) solar cell structure on multicrystalline silicon are reported. A significant gain in monofacial efficiency of +0.7%abs compared to the industry standard of aluminium back surface field (Al-BSF) cells has been achieved. Due to double-sided current collection, the BOSCO cell is a promising candidate to enable bifacial applications for material of lower diffusion lengths, in contrast to most published structures requiring high diffusion lengths.

The adhesion and contact resistivity of plated solar cell front contacts on a nickel seed layer can be improved by thermal silicidation of the Ni–Si interface. Formation of deep local nickel sicilide structures harms the cell performance. In the presented Letter, critical silicide structures were localized with a precision of 1 μm in top view. Subsequent cross-section studies reveal micro-defects.

The power conversion efficiency (PCE) values of devices with and without untreated WS₂ are both 1.84%. After performing a UV-ozone (UVO) treatment on the WS₂, the PCE increases to 2.4%. Upon inserting poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) between the WS₂ and the active layer, the PCE value increases to 3.07%, which is superior to that of the device employing only PEDOT:PSS (2.87%).

A method to passivate the surface of a wafer/silicone/glass stack to state-of-the-art values (SRV < 4 cm/s) is presented. The method is based on an O₂-plasma and an HF/TMAH/HF cleaning sequence that increase the silicone cross-linking and its resilience to process-induced degradation. The method is proven to work for three different silicone-based photovoltaic (PV) encapsulants and is believed to significantly broad the adhesive choice for module-level processing of wafer-based silicon solar cells.

A hybrid structure, consisting of a transparent conductive oxide layer and a silver nanoparticle mesh, is demonstrated to have high electrical conductance (<5 Ω/square sheet resistance) and high visible transparency (∼86%). This structure enables a separate optimization of the electrical and optical requirements, which provides benefits for applications in solar cells and other devices.

Environment-friendly and cost-effective Cu₂ZnSnS₄ (CZTS) thin film solar cells are expected to be alternatives for commercialized Cu(InGa)Se₂ (CIGS) and CdTe solar cells. In this Letter, epitaxial growth of CZTS on ZnS (100) substrate was achieved by radio frequency magnetron sputtering from a single CZTS target for investigation of the fundamental properties of the CZTS absorber itself.

Huge excitonic dipole moments inherent to wurtzite GaN/AlN quantum dots cause their particular vulnerability to emission line widths broadening in contrast to less-polar systems (e.g. arsenides). Defect-induced charges in the vicinity of these nitride quantum dots interact with the confined excitons, continuously affecting their emission energy, as approved by the presented emission line widths statistics for hundreds of individual emitters.

The mechanical–electrical conversion of GaN nanowires (NWs) is investigated. An average output voltage of about –74 mV for a large NW ensemble and a maximum output voltage reaching –443 mV ± 2% per NW are demonstrated. This latter output voltage is the highest value reported so far for GaN NWs and offers promising prospects for high-efficiency piezogenerators.

Epitaxial (Cr_1–xMn_x)₂AlC (x = 0.2) thin films were synthesized by cathodic arc deposition. Vibrating sample magnetometry measurements reveal (Cr,Mn)₂AlC as a new member in the recently discovered group of magnetic MAX phases. Magnetic transition temperature significantly higher than room temperature and magnetic moment >0.16 μB/M-atom are concluded.

The Letter demonstrates a new approach to enhancing the quantum efficiency of GaN-based light emitting diodes by insertion of multiple tunnel junctions into the active region which allow for the repeated use of electrons and holes for photon generation.

Fano resonance assisted two-photon luminescence in the plasmonic heptamer can be used to realize high performance refractive index sensing. The sensitivity of this method is about one order of magnitude better than the conventional refractive index sensing strategy utilizing Fano resonance while the size of the sensing probe can be further reduced at the same time.

Due to the barrier-height lowering at high temperature, the apparent degradation on sneak current and current distribution are major challenges, especially for the scaled one-diode–one-resistor (1D1R) resistive random access memory (RRAM) crossbar arrays. Therefore, the excellent high-temperature switching properties are important for production. In this study, the lower high-temperature sneak current and tighter high-temperature current distribution can be reached by Y₂O₃/TiO_x RRAM structure, which has the potential for future application.

In this Letter, the authors studied the quantum confinement in charged graphene quantum dots (GQDs), which is found to be clearly edge and shape dependent. It is revealed that the charged GQD is characterized by highly non-uniform excess charge distribution, irregular Coulomb diamonds, random energy spectrum shift and level statistics suggesting quantum chaos.

The authors investigated the effect of layer-by-layer AuCl₃ doping on the electrical and optical properties of stacked graphene films. Graphene was chemically doped by AuCl₃ solution. Different configurations are characterized by using four-point probe measurements, optical transmittance measurements, scanning electron microscopy, and micro-Raman spectroscopy. Better performances considering both sheet resistance and optical transmittance are observed from the configurations with the top-layer doped.

Avoiding misfit dislocation generation in nanowire (NW) heterostructure with lattice mismatch is a crucial topic for high-quality heteroepitaxy. In this Letter, the plastic relaxation introduced by typical 60° mixed dislocation in zinc-blende axial NW heterostructures are evaluated by numerical Peach–Koehler approach. The equilibrium position and critical diameter are theoretically predicted for cylindrical NW epilayers grown on both NW and bulk substrates.