A5102025669- Silicon and Solar Cell Technologies
- Semiconductor materials and interfaces
- Thin-Film Transistor Technologies
- solar cell performance optimization
- Silicon Nanostructures and Photoluminescence
- Integrated Circuits and Semiconductor Failure Analysis
- Photovoltaic System Optimization Techniques
- Lanthanide and Transition Metal Complexes
- Organic Light-Emitting Diodes Research
- Photovoltaic Systems and Sustainability
- Magnetism in coordination complexes
- Chalcogenide Semiconductor Thin Films
- Nanowire Synthesis and Applications
Fraunhofer Institute for Solar Energy Systems
2014-2018
University of Freiburg
2015
Siemens (Germany)
2013
Small quantities of Cl(-) ions result in dramatic reductions the performance ionic transition metal complexes light-emitting electrochemical cells. Strong ion-pairing between aromatic protons and chloride has been established both solid state solution. X-ray structural determination 2{[Ir(ppy)2(bpy)][Cl]}·2CH2Cl2·[H3O]·Cl reveals unusual nature an impurity encountered preparation [Ir(ppy)2(bpy)][PF6].
Bifacial n-type silicon solar cells typically feature two highly doped areas, namely, a boron-doped emitter and phosphorus-doped back-surface field (BSF). Complexity of the process sequence for forming these areas is one major obstacles industrial application. This study investigates POCl <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> -based codiffusion that allows BSF in single high-temperature step. As boron source, we use...
Abstract Bifacial applications are a promising way to increase the performance of photovoltaic systems. Two silicon solar cell concepts suitable for bifacial operation passivated emitter, rear totally diffused (PERT) and both sides collecting contacted (BOSCO) concepts. This work investigates potential these by means in‐depth numerical device simulation experiment with focus on impact varying material quality. It is shown that PERT concept (representing structure front‐side emitter only)...
We present co-diffused bifacial n-type solar cells (CoBiN) with peak efficiencies of 19.9 %. The codiffusion process is based on a high temperature step in an atmosphere containing POCl3 and BSG/SiOx layer stack deposited by atmospheric pressure chemical vapor deposition. Secondary ion mass spectroscopy measurements show that the reaction SiOx results formation PSG converting fraction layer. Electrochemical capacitance voltage do not detect influence boron emitter.
We present a new simplified and fast process sequence for the fabrication of large area bifacial n‐type silicon solar cells. A co‐diffusion simultaneously forms boron‐doped emitter phosphorus‐doped back surface field in one single high temperature step. use borosilicate glasses (BSG) deposited by atmospheric pressure chemical vapor deposition (APCVD) POCl 3 gas ambient as doping sources. Tailoring diffusion yields reduced time 114 min, well suited production. The presented allows lean...
The authors present a fully solderable, co-diffused and bi-facial PERT solar cell where the rear BSG/SiN stack acting both as dopant passivation source reaching mean efficiency of 20.4 %. conductivity induced by presence p+ layer at reduces series resistance losses significantly simultaneously enabling use lowly doped Si wafers that reduce B-O degradation while maintaining high fill factor. Parallel processed, mono-facial pendants reach same level. A higher FF for mono-facials is compensated...
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...
We present codiffused bifacial n-type (CoBiN) solar cells on 156 mm Czochralski grown (Cz) Si wafers with peak efficiencies of 19.6 % fabricated using a lean industrial process. Simultaneous diffusion phosphorus back surface field (BSF) and boron emitter in one single tube furnace process, the so called codiffusion, leads to significant process simplification. Manipulation borosilicate glass (BSG) layer, deposited by atmospheric pressure chemical vapor deposition (APCVD) prior POCl3 based...
In this study, several diffusion sources are investigated, aiming at codiffusion for the fabrication of back-contact back-junction (BC-BJ) silicon solar cell. As a gaseous source, POCl <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> -diffusion process is and solid sources, phosphorusand boron-doped silicate glass (PSG BSG) deposited by means plasma-enhanced chemical vapor deposition considered. The n <sup...
We present an analytical model for the internal resistance of passivated emitter and rear totally diffused (PERT) solar cells. First, we apply Saint-Cast spreading a cell (PERC) structure with line-shaped contacts. To account additional vertical current flow through silicon wafer lateral back surface field PERT structure, add parallel path using common expressions. compare models two-dimensional numerical simulations based on Quokka 3 find deviations less than 6% resistance. In addition,...
We demonstrate a bifaciality of 88.0% for 6-inch bifacial p-type Cz-Si passivated emitter and rear cells (biPERC) increase their side energy conversion efficiency to 18.0% by minor adaptions in the fabrication sequence. utilize “pPassDop” concept on cells’ that applies an aluminum oxide boron-doped silicon nitride (SiN <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</inf> :B layer stack simultaneous passivation doping source. Laser forms local...
We present an efficiency potential analysis of passivated emitter and rear cells (PERC) totally diffused (PERT) cells, based on numerical simulations covering a wide range parameters using state-of-the-art design experiment metamodeling approach. make full use the metamodel optimize contact distance in each simulation by defining it as free variable. PERT solar are simulated respecting carrier absorption at boron doped back surface field (BSF). As result, PERC show highest overall low base...
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...
We investigate the impact of different oxygen concentrations during boron diffusion at 950°C using borosilicate glass (BSG) layers deposited by atmospheric pressure chemical vapor deposition. Therefore, we vary concentration in BSG layer and gaseous ambient high-temperature step. Characterization includes sheet resistance as well electrochemical capacitance voltage measurements for determination resulting doping profile. In addition, perform quasi steady-state photoconductance to influence...
We present different models for the internal resistance of passivated emitter and rear totally diffused (PERT) solar cells. First we apply model Gelmont Shur spreading a cell (PERC) structure with line-shaped contacts adapt this to account elliptic contact shape Al-alloyed contacts. To additional vertical current flow through silicon wafer lateral back surface field (BSF) PERT structure, evaluate an alternative using analogy transfer length method (TLM) problem. For experimental...