A5077635779- Silicon and Solar Cell Technologies
- Thin-Film Transistor Technologies
- Semiconductor materials and interfaces
- Semiconductor materials and devices
- solar cell performance optimization
- Integrated Circuits and Semiconductor Failure Analysis
- Silicon Nanostructures and Photoluminescence
- Photovoltaic System Optimization Techniques
- Advancements in Semiconductor Devices and Circuit Design
- Nanowire Synthesis and Applications
- Advanced Surface Polishing Techniques
- Chalcogenide Semiconductor Thin Films
- Ion-surface interactions and analysis
- Diamond and Carbon-based Materials Research
- Electron and X-Ray Spectroscopy Techniques
- Silicon Carbide Semiconductor Technologies
- Advanced optical system design
- Adaptive optics and wavefront sensing
- Photovoltaic Systems and Sustainability
- Optical Coatings and Gratings
- Organic Electronics and Photovoltaics
- Advanced Materials and Semiconductor Technologies
- Copper Interconnects and Reliability
- Cardiac tumors and thrombi
- Plasma Diagnostics and Applications
Fraunhofer Institute for Solar Energy Systems
2015-2024
Fraunhofer Society
2010-2013
École Normale Supérieure - PSL
2006
Aluminum oxide layers can provide excellent passivation for lowly and highly doped p-type silicon surfaces. Fixed negative charges induce an accumulation layer at the interface, resulting in very effective field-effect passivation. This paper presents negatively charged (Qox=−2.1×1012 cm−2) aluminum produced using inline plasma-enhanced chemical vapor deposition system, leading to low recombination velocities (∼10 cm s−1) on low-resistivity substrates. A minimum static rate (100 nm min−1)...
Ultrathin (7 nm) atomic layer deposited Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> layers and high-deposition-rate plasma-enhanced chemical vapor AlO xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> have been applied characterized as rear-surface passivation for high-efficiency silicon solar cells. The excellent efficiency values (up to 21.3%-21.5%) demonstrate that both...
For the passivation of p-type silicon surfaces, we investigate layer systems consisting a thin thermally grown SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> and different dielectric capping layers deposited by means plasma-enhanced chemical vapor deposition (PECVD). We find that thermal thickness strongly impacts quality interface parameters stacks. Capacitance-voltage measurements reveal for Al O...
Current studies reveal the expectation that photovoltaic (PV) energy conversion will become front-runner technology to stem against extent of global warming by middle this century. In 2019, passivated emitter and rear cell (PERC) design has taken over majority solar production. The objective paper is review fundamental physics underlying architecture, its development past few decades an industry main stream product, as well in-depth characterization current cells future potential device...
Reducing wafer thickness while increasing power conversion efficiency is the most effective way to reduce cost per Watt of a silicon photovoltaic module. Within European project 20 percent on less than 100-µm-thick, industrially feasible crystalline solar cells ("20plµs"), we study whole process chain for thin wafers, from wafering module integration and life-cycle analysis. We investigate three different cell fabrication routes, categorized according temperature junction formation doping...
The loss analysis of state‐of‐the‐art p‐type Czochralski‐grown silicon passivated emitter and rear solar cells (PERC) fabricated in a manner close to industrial production is presented this paper. 6‐inch are featuring homogeneous on the front side, an Al 2 O 3 passivation layer local contacts side. peak energy conversion efficiencies obtained 21.1% for standard antireflection coating (ARC) 21.4% double‐layer ARC. based extended characterization special samples, which allow separation...
This work presents a detailed study of c-Si/Al2O3 interfaces ultrathin Al2O3 layers deposited with atomic layer deposition (ALD), and capped SiNx plasma-enhanced chemical vapor deposition. A special focus was the characterization fixed charge density these dielectric stacks interface defect as function thickness for different ALD processes (plasma-assisted thermal ALD) post-deposition treatments. Based on theoretical calculations extended Shockley–Read–Hall model surface recombination,...
This article introduces a postmetallization "passivated edge technology" (PET) treatment for separated silicon solar cells consisting of aluminum oxide deposition with subsequent annealing. We present our work on bifacial shingle that are based the passivated emitter and rear cell concept. To separate devices after metallization firing, we use either conventional laser scribing mechanical cleaving (LSMC) process or thermal separation (TLS) process. Both processes show similar pseudo fill...
Abstract This work demonstrates the efficient optical and passivation properties provided by hydrogenated silicon nitride (SiN x :H) layers deposited in a lab‐scale atmospheric pressure plasma enhanced chemical vapor deposition (AP‐PECVD) reactor. By applying modulated low‐frequency (200 kHz), homogeneous SiN :H layers, with small variances thickness w refractive index n (Δ ≤ 2 nm; Δ 0.02), were achieved on surface area of 45 × 55 mm . The use voltage amplitude modulation enabled discharge...
This paper focusses in particular on the influence of layer thickness passivation quality, charge density and interface defects PECVD Al2O3 layers c-Si surfaces. The surface recombination velocity defect are observed to increase by decreasing thickness. However, negative charges remains almost constant with values around 3 1012 cm-2. An optimal quality is obtained for thicknesses 15 nm higher. A linear relation between Dit was established, allowing estimation electron capture cross section...
In this publication, the activation and degradation of passivation quality plasma-enhanced chemical vapor deposited aluminum oxide (Al2O3) layers with different thicknesses (10 nm, 20 110 nm) on crystalline silicon (c-Si) during long high temperature treatments are investigated. As indicated by Fourier Transform Infrared Spectroscopy, concentration tetrahedral octahedral sites within Al2O3 layer changes correlates amount negative fixed charges at Si/Al2O3 interface, which was detected Corona...
A study of the thermally activated negative fixed charges Qtot and interface trap densities Dit at between Si thermal atomic-layer-deposited amorphous Al2O3 layers is presented. The activation was conducted annealing temperatures 220 °C 500 for durations 3 s 38 h. temperature-induced differences in were measured using characterization method called corona oxide semiconductors. Their time dependency fitted stretched exponential functions, yielding energies EA = (2.2 ± 0.2) eV (2.3 0.7) Dit,...
Abstract In this work, we analyse passivated emitter and rear cells (PERC), based on wafers made from seed manipulation for artificially controlled defects technique (SMART) monocrystalline silicon, magnetically grown conventional Czochralski (mCz Cz) high‐performance multicrystalline (hpm) silicon. All were processed identically except the hpm wafers, which received an acidic texture instead of random pyramids. The energy conversion efficiency η SMART 21.4 % is similar to mCz (21.5 ) while...
In this paper an analytical model of the effective recombination (Seff) on back surface locally contacted solar cell is developed. We justify approach by first showing that three-dimensional (3D) problem can be reduced to a one-dimensional (1D) calculating Seff. The values Seff calculated with our and two existing models are compared finite element simulations. A large range cases from high low scale structures, including variation in velocity at passivated area investigated. presented good...
We present a detailed study about the influence of post-deposition temperature treatment on PECVD Al2O3 passivation layers. Fourier transform infrared spectroscopy (FTIR) and quasi-steady-state photoconductance (QSSPC) were applied for characterization. observed several indications structural changes layer with annealing duration, thickness. A shift an increase Si-O vibrational mode (1100- 980 cm-1) in FTIR measured changing thickness is presented. Structural temperature, thickness, caused...
The performance of PERC solar cells benefits from a smooth rear surface due to reduced recombination and increased light trapping. State the art roughness is defined solely by polishing silicon removal. However initial texture height can vary, therefore there no universal definition roughness. In this work parameters an earlier study will be used determine mono-crystalline industrial p-type [1]. effects side on passivation quality thus minority carrier lifetime discussed. Additionally...
In this paper, we study the influence of modifying geometry nanotexture on its electrical properties. Nanotexture is formed by an industrially feasible dry-chemical etching process performed entirely in atmospheric pressure conditions. A surface modification developed that allows low recombination velocities (Seff,min ≤ 10 cm/s) nanotextured surfaces. By simultaneously improving passivation and emitter diffusion processes, achieve equivalent level (VOC,impl ≥ 670 mV) for surfaces to...
This work aims to improve the rear-side properties of p-type monocrystalline silicon solar cells by using passivated emitter and rear locally diffused (PERL) cell concept. To realize side structure, so-called PassDop approach was used combining both surface passivation local doping. The concept utilizes a multifunctional, doped AlO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> /SiN :B layer stack; localized structuring is achieved...
In this paper, we study the impact of change in emitter diffusion profiles on electrical characteristics nanotextured surfaces formed by an inline plasma-less dry-chemical etching process. Our experimental results and process simulations suggest that a deeper highly doped region significantly higher inactive P concentration plays determining role defining recombination, as well resistive losses surfaces. Low saturation current densities phosphorous-diffused are achievable after passivation...
Cast-mono silicon material is interesting for its lower carbon footprint compared to Czochralski (Cz) monocrystalline silicon. However, solar cells fabricated using cast-mono (CM) show performances. In this work, two routes make advantageous over Cz are considered. The first route further reduce of silicon, by Upgraded Metallurgical Grade (UMG-Si) feedstock instead Solar (SoG-Si) feedstock. TOPCon both feedstocks, and growth technology, industrial-type furnaces. Laboratory studies that...
We present small-area metal wrap through solar cells with passivated rear side (MWT-PERC), screen-printed metallization, and a homogeneous industrial-like emitter showing an efficiency of 20.2%. A comparison H-pattern reference aluminum back surface field confirms the advantages MWT-PERC approach reveals significant synergistic effects rear-surface passivation metallization.