A5007338566- Chalcogenide Semiconductor Thin Films
- Quantum Dots Synthesis And Properties
- Semiconductor materials and interfaces
- Copper-based nanomaterials and applications
- Advanced Thermoelectric Materials and Devices
- ZnO doping and properties
- Thin-Film Transistor Technologies
- Silicon and Solar Cell Technologies
- solar cell performance optimization
- Phase-change materials and chalcogenides
- Semiconductor Lasers and Optical Devices
- Economic and Technological Innovation
- Machine Learning in Materials Science
- Silicon Carbide Semiconductor Technologies
- Solar Thermal and Photovoltaic Systems
- Photonic and Optical Devices
- Advanced Materials Characterization Techniques
- Advanced Semiconductor Detectors and Materials
- Perovskite Materials and Applications
- Semiconductor Quantum Structures and Devices
University of Cambridge
2024
University of Luxembourg
2023-2024
Institut de Recerca en Energia de Catalunya
2023
Carl von Ossietzky Universität Oldenburg
2018
Abstract Based on the high power conversion efficiencies and compatibility toward large-area deposition techniques, Cu(In,Ga)(S,Se) 2 (CIGSSe) phototvoltaic absorbers are currently at forefront of chalcopyrite thin-film solar cell technology. The performance these cells is critically dependent properties interface between p-type absorber n-type buffer window layers. Due to complex defect physics chalcopyrites in general, defect-electronic surface particular concern. In this regard, CIGSSe...
Abstract Doping an indium sulfide buffer layer with sodium is a promising route to replace the “state‐of‐the‐art” CdS in chalcopyrite‐based thin‐film solar cells, as it achieves efficiencies high 17.9% for large‐area devices (30 cm × 30 cm). We report on chemical and electronic structure of In x S y :Na/CuIn(S,Se) 2 (CISSe) interface cells by means photoelectron, soft x‐ray emission, inverse photoemission spectroscopy. For as‐deposited :Na layers, we find sulfur‐poor surface and, comparison...
We report on crossing the 20% efficiency line for thin-film solar modules. The of our cadmium-free Cu(In,Ga)(S,Se) <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (CIGSSe) mid-sized modules (30 × 30 cm <sup xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) based cost-efficient AVANCIS stacked elemental layer – rapid thermal processing absorber process has evolved in last two years reaching 19.6%, 19.8% and recently we have achieved an...
Record efficiency in chalcopyrite-based solar cells Cu(In,Ga)(S,Se)2 is achieved using a gallium gradient to increase the bandgap of absorber toward back side. Although this structure has successfully reduced recombination at contact, we demonstrate that industrial absorbers grown pilot line Avancis, part source non-radiative recombination. Depth-resolved photoluminescence (PL) measurements reveal two main radiative paths 1.04 eV and 1.5–1.6 eV, attributed phases low high material,...
Using device simulations, we investigate the change of temperature behavior Cu(In,Ga)(Se,S)2 solar cells. Our goal is to understand performance ratio (PR), normalized energy yield (Y), and coefficient open-circuit voltage as a contribution PR Y. Therefore, simulate temperature-dependent current–voltage (IVT) curves apply weather data hot climate location calculate For differently widened absorber band gap profiles, observe an increase open circuit leading enhancement relative PR. In addition...
A combination of undoped ZnO and ZnO:Al is the most commonly used window layer stack for chalcopyrite solar cells. The high carrier density thickness required to achieve a sufficiently low sheet resistance lead optical absorption cause losses in photocurrent, particular monolithically interconnected modules. Additionally, band gap CdS buffer un‐doped limit blue response. These could be avoided by using transparent conductive oxide with mobility wider which also has wide gap. We propose...
Two R&D approaches for advanced Cd-free PVD buffer layers in our CIS device stack are demonstrated the present contribution allowing to address goal of CIGSSe PV industry increased module conversion efficiencies and/or reduced Capex and Opex costs further production capacity expansion. With In <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> S xmlns:xlink="http://www.w3.org/1999/xlink">y</sub> :Na layer we have reached 18% efficiency...
The chemical and electronic structure of the interface between a sputter‐deposited Zn(O,S) buffer layer an industrial Cu(In,Ga)(S,Se) 2 (CIGSSe) absorber for thin‐film solar cells is investigated with X‐ray UV photoelectron spectroscopy, inverse photoemission emission spectroscopy. We find CIGSSe surface band gap 1.61 (±0.14) eV, which significantly increased as compared to minimal value derived bulk‐sensitive methods (≈1.1 eV). no indication diffusion elements into layer. Surface‐...
Typical features of sequentially processed Cu(In1−xGax)(Sey−1Sy)2 (CIGSSe) thin film solar cells such as roughness at particular interfaces and free absorber volume (voids) might influence the device characteristics significantly. We investigated both, voids, on cell performance parameters well capacitance by means two-dimensional (2D) simulations. Increased was found to enhance light absorption carrier collection whereas increased interface recombination textured heterojunction is minor...
Abstract A 1D single-cell simulation model for a laminated Ga-rich <?CDATA $30\times{30}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>30</mml:mn> <mml:mo>×</mml:mo> <mml:mrow> </mml:mrow> </mml:math> cm 2 n-ZnO/ZnOS/Cu(In,Ga)(S,Se) /Mo(Se,S) -based solar module with power conversion efficiency of close to 19% is developed and calibrated on its current–voltage (IV), capacitance–voltage (CV), external quantum efficiency(EQE) $V_{oc}(G)$?> <mml:msub>...
We investigated an open‐circuit voltage phenomenon of Cu(In,Ga)(Se,S) thin‐film solar cells observed by device simulations which is manifested in anomalous temperature dependence (meaning deviating from the linear caused saturation current) induced a variation buffer electron affinity. In order to study origin this effect, we performed temperature‐dependent current–voltage characteristics while separately consider thermionic emission and classical drift‐diffusion model as decisive charge...
We present a one-dimensional simulation model for high efficiency Cu(In,Ga)(Se,S)2 solar cells with novel band alignment at the hetero-junction. The study is based on new findings about doping concentration of InxSy:Na buffer and i-ZnO layers as well comprehensive cell characterization by means capacitance, current voltage, external quantum measurements. results show good agreement experimental data over broad temperature range, suggesting an interface-near region (INR) approximately 100 nm...
Dry buffer layer deposition techniques for chalcopyrite (CIGSSe)-based thin-film solar cells lack the surface-cleaning characteristics of commonly used CdS or Zn(O,S) wet-chemical bath deposition. A UV-induced ozone and/or a low-energy Ar+-ion treatment could provide dry CIGSSe surface cleaning steps. To study impact these treatments, chemical structure absorber is investigated. For this purpose, set surface-sensitive spectroscopic methods, i.e., laboratory-based x-ray photoelectron...