Surface Photovoltage Study of GaAsSbN and GaAsSb Layers Grown by LPE for Solar Cells Applications

The properties of GaAsSbN and GaAsSb layers grown by liquid-phase epitaxy on n-GaAs substrates were investigated in a comparative plan with a view of their possible application in multi-junction solar cells. To avoid non-uniformity effects in the composition of these compounds with two or three different group-V volatile elements, the crystallization was carried out from finite melt with a thickness of 0.5 mm at low (<560 °C) temperatures. X-ray microanalysis and X-ray diffraction were used to determine the composition, lattice mismatch, and crystalline quality of the epitaxial layers. The morphology and surface roughness were examined by atomic force microscopy. Surface photovoltage (SPV) spectroscopy at room temperature was applied to study the optical absorption properties and the photocarrier transport in the samples. The long-wavelength photosensitivity of the GaAsSbN and GaAsSb layers, determined from their SPV spectra, is extended down to 1.2 eV. Although GaAsSb has a slightly larger lattice mismatch with the GaAs substrate compared to GaAsSbN, it presents a higher photoresponse, since, in GaAsSbN, the incorporation of N induces additional recombination centres. Therefore, GaAsSb could be an alternative to GaAsSbN for solar cell applications

A Modular Method for the Calculation of Transmission and Reflection in Multilayered Structures

We describe a new modular method for the calculation of wave propagation in stratified media based on the direct use of reflection and transmission coefficients. Within this reflection from the left, transmission, and reflection from the right (LTR) method we define addition and multiplication operators that enable the theoretical construction of any multilayered structures from substructures. This modular concept allows for the design and analysis of complex multilayer structures for optical devices. (C) 2001 Optical Society of America.</p

Surface photovoltage characterisation of metal halide perovskite on c-SI using kelvin probe force microscopy and metal-insulator-semiconductor configuration

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Surface photovoltage study of metal halide perovskites deposited directly on crystalline silicon

International audienc

Modelling investigations of surface photovoltage including surface defects

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