An electrical device includes a substrate with a compressive layer, a neutral stress buffer layer and a tensile stress compensation layer. The stress buffer layer and the stress compensation layer may each be formed with aluminum nitride using different processing parameters to provide a different intrinsic stress value for each layer. The aluminum nitride tensile layer is configured to counteract stresses from the compressive layer in the device to thereby control an amount of substrate bow in the device. This is useful for protecting fragile materials in the device, such as mercury cadmium telluride. The aluminum nitride stress compensation layer also can compensate for forces, such as due to CTE mismatches, to protect the fragile layer. The device may include temperature-sensitive materials, and the aluminum nitride stress compensation layer or stress buffer layer may be formed at a temperature below the thermal degradation temperature of the temperature-sensitive material.

A photon avalanche diode, includes a quartz substrate, a doped HgCdTe contact layer on the substrate, an absorbing HgCdTe layer on the contact layer, a larger bandgap HgCdTe layer on the absorbing layer, a doped HgCdTe layer for a top contact layer on the larger bandgap HgCdTe layer, and a non-absorbing HgCdTe metasurface on the top contact layer.

A perovskite-based solar cell comprising a transparent electrode disposed on a buffer layer that protects the perovskite from damage during the deposition of the electrode is disclosed. The buffer material is deposited using either low-temperature atomic-layer deposition, chemical-vapor deposition, or pulsed chemical-vapor deposition. In some embodiments, the perovskite material is operative as an absorption layer in a multi-cell solar-cell structure. In some embodiments, the perovskite material is operative as an absorption layer in a single-junction solar cell structure.

Disclosed are ultrathin layers of group II-VI semiconductors, group II-VI semiconductor superlattice structures, photovoltaic devices incorporating the layers and superlattice structures and related methods. The superlattice structures comprise an ultrathin layer of a first group II-VI semiconductor alternating with an ultrathin layer of at least one additional semiconductor, e.g., a second group II-VI semiconductor, or a group IV semiconductor, or a group III-V semiconductor.

A photovoltaic device is disclosed including at least one Cadmium Sulfide Telluride (CdS.sub.xTe.sub.1−x) layer as are methods of forming such a photovoltaic device.

A compact, three-dimensional (3D) photovoltaic charging system comprising a photovoltaic unit encased in a transparent housing, a power management unit, and a support base. The photovoltaic unit having non-coplanar photovoltaic surfaces that are positioned at a relative distance and a relative orientation. Compared to conventional flat solar panels, the 3D photovoltaic charging system can collect light vertically, therefore amplifying solar module power density, defined as power output per installation footprint area. A photo-tracking, 3D photovoltaic charging system is also described, having a photovoltaic unit encased in a transparent housing, a power management unit, and means to track a source of electromagnetic radiation. The photo-tracking, 3D photovoltaic charging system tracks a moving light source, resulting in improved light flux intake, and therefore, enhanced electric power output.

A method and system are provided for crystallizing thin films with a laser system. The method includes obtaining a thin film comprising a substrate and a target layer that contains nano-scale particles and is deposited on the substrate. The heat conduction between the target layer and the substrate of the thin film is determined based on thermal input from the laser system to identify operating parameters for the laser system that cause crystallization of the nano-scale particles of the target layer in an environment at near room temperature with the substrate remaining at a temperature below the temperature of the target layer. The laser system is then operated with the determined operating parameters to generate a laser beam that is transmitted along an optical path to impinge the target layer. The laser beam is pulsed to create a localized rapid heating and cooling of the target layer.

Disclosed is a photovoltaic device that includes a solar cell on a light transmissive substrate in the form of an array of equal diameter optical fibers laid adjacent to each other in the transversal direction of the fibers. With such an arrangement, light harvesting at high angles is improved by 30%.

A layer of an n-type chalcogenide compositions provided on a substrate in the presence of an oxidizing gas in an amount sufficient to provide a resistivity to the layer that is less than the resistivity a layer deposited under identical conditions but in the substantial absence of oxygen.

The present invention provides stretchable, and optionally printable, semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed or otherwise deformed. Stretchable semiconductors and electronic circuits of the present invention preferred for some applications are flexible, in addition to being stretchable, and thus are capable of significant elongation, flexing, bending or other deformation along one or more axes. Further, stretchable semiconductors and electronic circuits of the present invention may be adapted to a wide range of device configurations to provide fully flexible electronic and optoelectronic devices.