GaAs Solar Cells Grown Directly on V-Groove Si Substrates.

The direct epitaxial growth of high-quality III-V semiconductors on Si is a challenging materials science problem with a number of applications in optoelectronic devices, such as solar cells and on-chip lasers. We report the reduction of dislocation density in GaAs solar cells grown directly on nanopatterned V-groove Si substrates by metal-organic vapor-phase epitaxy. Starting from a template of GaP on V-groove Si, we achieved a low threading dislocation density (TDD) of 3 × 10 cm in the GaAs by performing thermal cycle annealing of the GaAs followed by growth of InGaAs dislocation filter layers.

Pulsed Laser Deposition of Epitaxial SrTiO/SrAlO Templates as a Water-Soluble Sacrificial Layer for GaAs Growth and Lift-Off.

Despite the record-high efficiency of GaAs solar cells, their terrestrial application is limited due to both the particularly high costs related to the required single-crystal substrates and epitaxial growth. A water-soluble lift-off layer could reduce costs by avoiding the need for toxic and dangerous etchants, substrate repolishing, and expensive process steps. SrAlO (SAO) is a water-soluble cubic oxide, and SrTiO (STO) is a perovskite oxide, where ≈ 4 × ≈ (2√2) .

Solution Cathode Glow Discharge Coupled to Atmospheric Pressure Chemical Ionization for Elemental Detection of S and P in Organic Compounds.

We report a post-plasma chemical ionization approach to evaluate solution cathode glow discharge (SCGD) for S and P elemental analysis. Here, the SCGD serves as a reactor to produce chemical vapors for S and P from organic compounds containing these elements, while a corona discharge operated in negative mode is used to ionize the products. The approach creates long-lived ions in atmospheric pressure, enabling direct investigation of chemical vapor products via mass spectrometric and ion mobility separations.