Design and fabrication of field-effect III-V Schottky junction solar cells

“A new concept of field-effect photovoltaic devices with a focus on design and fabrication of single and multi-junction solar cells using III-V materials has been shown and proved. Schottky solar cells based on metal-(insulator)-semiconductor (M-I-S) structure have been designed and fabricated using various wide bandgap semiconductors, such as GaAs and Al0.3Ga0.7As. A secondary bias layer has been introduced to the device structure, in which it creates additional band bending and subsequently depletion region at the flat band regions on the top surface of the device. It should be mentioned that the bias layer is designed to be electrically isolated from the main current collection contacts, in order to prevent the decrease in Schottky barrier height due to change in applied forward voltage or external load resistance. The electrical and optical characterization results from these Isolated Collection and Biasing Schottky Solar Cells (ICBS) show an improvement in photovoltaic response compared to conventional Schottky junction solar cells. This demonstrates the effectiveness of this novel strategy to design and fabricate high-efficiency multi-junction solar cells”--Abstract, page iii

XPS characterization of Al\u3csub\u3e2\u3c/sub\u3eO\u3csub\u3e3\u3c/sub\u3e/ZnO ultrathin films grown by atomic layer deposition

© 2020 Author(s). The near-surface compositional properties of double-layer Al2O3/ZnO ultrathin films, grown on the n-type GaAs substrate using the atomic layer deposition (ALD) technique, are analyzed by means of high-resolution x-ray photoelectron spectroscopy (XPS). This structure has been used as the dielectric or the passivation layer in microelectronic devices, such as metal-oxide-semiconductor (MOS) capacitors, field-effect transistors, and Schottky junctions. The XPS spectra of double-layer Al2O3/ZnO thin films were obtained using monochromatic Al kα monochromatic radiation at 1486.6 eV and included an overall survey scan, in addition to the high-resolution spectra of Zn 2p, Al 2p, O 1s, Ga 2p, and As 3d

PEDOT:PSS/n-Si Hybrid Solar Cells with Al₂O₃ Interfiacial Passivation Layer

Hybrid solar cells, consisting of both organic and inorganic layers have shown to be promising in developing solar cells with suitable photovoltaic properties, advantage of low temperature processing and much lower production cost than conventional p-n junction solar cells. For example, poly (3,4-ethylene-diozythiophene): polystyrenesulfonate (PEDOT:PSS) with work function of 5.1 eV and spin-coated on Si substrate leads to development of a rectifying Schottky junction and is used to design and fabricate hybrid solar cells, in which the organic PEDOT:PSS acts as a hole transporting layer. It has been shown in that the organic layer in a PEDOT:PSS/ n-Si hybrid solar cell, fabricated at temperatures below 100 C°, can also act as electron blocking layer, resulting in a low reverse saturation current density of 3.8 x 10-9 mA/cm2 and Schottky barrier height of 0.8 eV. Furthermore, Aluminum oxide (Al2O3) is shown to be effective as the passivation layer in improving the photovoltaic properties of solar cells by passivating the dangling bonds and reducing the density of surface states