A Lightweight Flexible Solar Cell Based on a Heteroepitaxial InGaP/GaAs Structure

Technical Physics - Problems arising in fabrication of lightweight flexible solar cells based on heteroepitaxial AIIIBV structures with substrate etching are discussed. Possible solutions are...     

Optical properties of elements prepared from different parts of rapidly grown KDP and DKDP crystals

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 3, pp. 462–466, September, 1991.     

Ellipsometric detection of GaAs(0 0 1) surface hydrogenation in H2 atmosphere

Optical properties of MBE-grown GaAs(0 0 1) surfaces have been studied by spectroscopic ellipsometry under dynamic conditions of ramp heating and cooling after desorption of passivating As-cap-layer with low pressure H₂ atmosphere (14 Torr) applied to the surface. The temperature dependence of GaAs pseudo-dielectric function with atomically smooth (0 0 1) surface carrying the fixed Ga-rich (4 × 2) reconstruction was obtained for the temperature range of 160–600 °C. It is shown ellipsometrically that GaAs(0 0 1) heating in the molecular hydrogen atmosphere results in the formation of hydrogenated layer on the surface.     

Influence of the structural surface state on the formation of a relief and morphology of GaAs(001) layers during molecular-beam epitaxy and vacuum annealing

Methods of reflection high-energy electron diffraction (RHEED) and atomic force microscopy (AFM) are used to investigate the special features of morphological changes on the GaAs(001) surface during the molecular-beam epitaxy (MBE) growth and vacuum annealing. A relationship is revealed between the superstructural state of the surface and the character of these changes. Thermodynamic conditions of epitaxial GaAs(001) growth with the most structurally perfect surface are established. The characteristics of the processes causing evolution of the relief during MBE growth in states with reconstruction (2 × 4) are determined. A new technique that allows the efficiency of smoothing of the GaAs(001) surface to be increased considerably by annealing in an arsenic flow is suggested and tested. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 5–13, September, 2008.