A5076399251- Silicon and Solar Cell Technologies
- Thin-Film Transistor Technologies
- Semiconductor materials and interfaces
- Integrated Circuits and Semiconductor Failure Analysis
- Silicon Nanostructures and Photoluminescence
- solar cell performance optimization
- Advancements in Semiconductor Devices and Circuit Design
- Semiconductor materials and devices
- Photovoltaic System Optimization Techniques
- Chalcogenide Semiconductor Thin Films
- Ion-surface interactions and analysis
- Photovoltaic Systems and Sustainability
- Advanced Materials Characterization Techniques
- 3D IC and TSV technologies
- Renewable energy and sustainable power systems
- Semiconductor Lasers and Optical Devices
- Copper Interconnects and Reliability
- Adaptive optics and wavefront sensing
- Metal and Thin Film Mechanics
- Advanced optical system design
- Perovskite Materials and Applications
- Diamond and Carbon-based Materials Research
- Additive Manufacturing Materials and Processes
- Energetic Materials and Combustion
Fraunhofer Institute for Solar Energy Systems
2015-2024
Fraunhofer Society
2010-2018
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...
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...
Abstract Low‐cost and high‐efficiency tandem solar cells are promising candidates for a future industrial mass production. Nowadays, the passivated emitter rear cell (PERC) technology makes up major market share; therefore, it is an attractive option to use PERC as bottom concept perovskite–silicon device. Long‐term optimization of led highly efficient, low‐cost, mature devices. For PERC‐like cells, mainly adapted front‐side design needed: Design constrains single junction relaxed some...
This work points out that the application of phosphorus emitters with low surface concentration Nsurf a few 1019 cm-3 in combination state-of-the-art screen-printed and fired silver contacts is no more limited by specific contact resistance ρC but dark saturation current densities underneath metal j0,met. Eight emitter doping profiles have been designed different ranging between 3.3·1019 1.2·1020 which feature very similar junction depths about 350 nm. The measured values for these are...
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...
One major loss mechanism for currently relevant solar cells [e.g., passivated emitter and rear (PERC)] is locally enhanced recombination at the interface between semiconductor metalization. For investigating these losses in detail, a reliable detection technique crucial. The photovoltaics community frequently applies an area-weighted model to extract local dark saturation current density metalized area of j <sub xmlns:mml="http://www.w3.org/1998/Math/MathML"...
We present high-performance metal wrap through+ (n-HIP-MWT+) solar cells (239 cm2 area) on n-type Czochralski-grown silicon (Cz-Si) wafers with a boron-doped front-side emitter. Peak conversion efficiencies of η = 19.5 % are measured using black chuck. Short-circuit current density jSC, open-circuit voltage VOC, and fill factor FF 39.6 mA/cm2, 650 mV, 75.7 %, respectively. The loss in caused by front rear side metallization, is found to be 16 mV for the n-HIP-MWT+ as well H-pattern...
The authors discuss industry related approaches at Fraunhofer ISE for bifacial p-type silicon solar cells, taking into account the well-known "passivated emitter and rear cell" (PERC), totally diffused" (PERT) locally (PERL) architectures. In case of PERC, challenges in terms alignment, printability importance bifaciality are addressed. PERT, a co-diffusion process is utilized to form back surface field simultaneously avoiding also critical shunts that can arise edges such devices. For PERL...
Metallization induced recombination losses are one dominant loss mechanism for current industrial solar cells. A precise determination of these is important contacting technology optimization, as well cell modeling. Usually, state-of-the-art approaches to determine j <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0,met</sub> , it assumed that the samples itself exhibit spatially uniform properties (e.g., carrier lifetime or sheet resistance)...
In this work we use Secondary Ion Mass Spectrometry (SIMS), Spreading Resistance Analysis (SRA), Stripping Hall (SH) and Electrochemical Capacitance Voltage (ECV) measurements to analyse different phosphorus-diffused emitters. Such data permit the detailed characterisation of emitter facilitate an optimisation diffusion process. The measurement techniques provide depth resolved information about phosphorus concentration conductivity as well electron mobility. We include overview techniques....
The concept of attaching a second deposition step at the end boron tribromide (BBr 3 ) diffusion is introduced, where describes an active nitrogen flow through BBr bubbler. This approach provides higher dose in borosilicate glass (BSG) which facilitates formation laser‐doped selective emitters. It found that hardly impacts as‐diffused charge carrier concentration profile comparison to diffusion without deposition. emitter sheet resistance R sh ≈ 110 Ω sq −1 and dark saturation...
Herein, boron‐doped cast‐monocrystalline silicon wafers that have been fabricated using the Seed Manipulation for ARtificially controlled defect Technique (SMART mono‐Si) are examined. Their suitability passivated emitter and rear cell (PERC) fabrication is investigated. Applying a zero busbar layout energy conversion efficiencies of η = 21.9% SMART mono‐Si, 22.2% gallium‐doped Cz‐Si (Cz‐Si:Ga), 22.3% (Cz‐Si:B) achieved at similar doping levels between 0.7 Ω cm ≤ ρ B 1.0 cm. Therefore,...
Abstract We present two approaches for high‐accuracy aligning of patterning processes with each other when fabricating solar cells. introduce the on example different which one is adjustable (laser process) and not (screen‐printing process). The basic idea to measure coordinates applied structures involved process at discrete grid points respect a reference coordinate system. chose such that they completely define final cell pattern. Then, we adjust point (the laser according pattern...
The HIP-MWT (High Performance Metal Wrap Through) cell is a simplified variant of the metal wrap through passivated emitter and rear (MWT-PERC). In this paper, transferability concept from lab scale to pilot line processing presented. suitability for integration in newly developed back contact modules tested demonstrated. Based on results lab-scale production, fabrication process improved. Moreover, options further accelerations cost reduction are identified. Finally solar module...
Via metallization is a main challenge in fabrication of metal wrap through (MWT) solar cells. Special attention has to be given the right choice both paste and suction process, order ensure low via-related series resistance. Five out six via pastes investigated show average resistances less than 4 mΩ by using an appropriate process. The contact formation base also particular interest since more advanced MWT structures no rear emitter present, as for example high-performance (HIPMWT) approach...
We investigate the impact of oxygen concentration during boron diffusion at peak temperatures varying from 875°C to 950°C using borosilicate glass layers (BSG) deposited by atmospheric pressure chemical vapor deposition (APCVD) as doping source. Therefore, we vary in BSG layer and gaseous ambient high temperature step. characterize process combinations with respect their resulting sheet resistance charge carrier profile. In addition, perform quasi steady-state photoconductance measurements...