Publications by Stefaan De Wolf

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Perovskite/silicon tandem solar cells are emerging as a high-efficiency and prospectively cost-effective solar technology with great promise for deployment at the utility scale. However, despite the remarkable performance progress reported lately, assuring ...

In amorphous/crystalline silicon heterojunction solar cells, optical losses can be mitigated by replacing the amorphous silicon films by wider bandgap amorphous silicon oxide layers. In this article, we use stacks of intrinsic amorphous silicon and amorpho ...

To study recombination at the amorphous/crystalline Si (a- Si:H/c-Si) heterointerface, the amphoteric nature of silicon (Si) dangling bonds is taken into account. Modeling interface recombination measured on various test structures provides insight into th ...

The a-Si:H / c-Si heterostructure, is an attractive solution to avoid the presence of highly recombinative metal contacts at the surfaces of c-Si based solar cells. To assure good interface passivation, insertion of a sandwiched thin device-grade intrinsic ...

The front transparent conductive oxide layer is a source of significant optical and electrical losses in silicon heterojunction solar cells because of the trade-off between free-carrier absorption and sheet resistance. We demonstrate that hydrogen-doped in ...

In this work, we use periodic density functional theory(periodic DFT) to rigorously assign vibrational spectra measured on nanorough wet-processed hydrogenated Si(111) surfaces. We compare Si(111)-(1x1) surfaces etched by dilute HF and NH4F, featuring two ...

Although charge‐carrier selectivity in conventional crystalline silicon (c‐Si) solar cells is usually realized by doping Si, the presence of dopants imposes inherent performance limitations due to parasitic absorption and carrier recombination. The develop ...

Carrier recombination at the metal contacts is a major obstacle in the development of high-performance crystalline silicon homojunction solar cells. To address this issue, we insert thin intrinsic hydrogenated amorphous silicon [a-Si: H(i)] passivating fil ...

Perovskite/crystalline silicon tandem solar cells have the potential to reach efficiencies beyond those of silicon single-junction record devices. However, the high-temperature process of 500 °C needed for state-of-the-art mesoscopic perovskite cells has, ...

Ultrathin layers of hydrogenated amorphous silicon (a-Si:H), passivating the surface of crystalline silicon (c-Si), are key enablers for high-efficiency silicon heterojunction solar cells. In this work, the authors apply highly sensitive attenuated total r ...

Silicon heterojunction solar cells have high open-circuit voltages thanks to excellent passivation of the wafer surfaces by thin intrinsic amorphous silicon (a-Si:H) layers deposited by plasma-enhanced chemical vapor deposition. We show a dramatic improvem ...

Crystalline silicon wafer (c-Si) can be extremely well passivated by plasma enhanced chemical vapor deposited (PECVD) amorphous silicon (a-Si:H) films. As a result, on flat substrates, solar cells with very high open circuit voltage are readily obtained. O ...

Intrinsic hydrogenated amorphous silicon (a-Si:H) films can yield in outstanding electronic surface passivation of crystalline silicon (c-Si) wafers as utilized in the HIT (heterojunction with intrinsic thin layer) solar cells. We have studied the correlat ...

We suggest a new solar cell loss analysis using theexternal quantumefficiency (EQE) measured with sufficiently high sensitivity to alsoaccount for defects. Unlike common radiative-limit methods, wherethe impact of deep defects is ignored by exponential ext ...

Carrier recombination at the metal-semiconductor contacts has become a significant obstacle to the further advancement of high-efficiency diffused-junction silicon solar cells. This paper provides the proof-of-concept of a procedure to reduce contact recom ...

We report on the fabrication of back-contacted silicon heterojunction solar cells with conversion efficiencies above 21%. Our process technology relies solely on simple and size-scalable patterning methods, with no high-temperature steps. Using in situ sha ...

Due to their high efficiencies combined with simple and cost-effective device fabrication, perovskite solar cells are promising candidates as top cells in tandem devices. For this application, the perovskite solar cell must be highly transparent at near-in ...

Silicon heterojunction solar cells typically use stacks of hydrogenated intrinsic/doped amorphous silicon layers as carrier selective contacts. However, the use of these layers may cause parasitic optical absorption losses and moderate fill factor (FF) val ...

This paper reports on the development of an innovative back-contacted crystalline silicon solar cell with passivating contacts featuring an interband tunnel junction at its electron-collecting contacts. In this novel architecture, named "tunnel-IBC", both ...

Excellent amorphous/crystalline silicon interface passivation is of extreme importance for high-efficiency silicon heterojunction solar cells. This can be obtained by inserting hydrogen-plasma treatments during deposition of the amorphous silicon passivati ...

Stefaan De Wolf

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Toward Stable Monolithic Perovskite/Silicon Tandem Photovoltaics: A Six-Month Outdoor Performance Study in a Hot and Humid Climate

Amorphous silicon oxide window layers for high-efficiency silicon heterojunction solar cells

Properties of interfaces in amorphous/crystalline silicon heterojunctions

Impact of annealing on passivation properties of a-Si:H / c-Si heterostructures

Hydrogen-doped indium oxide/indium tin oxide bilayers for high-efficiency silicon heterojunction solar cells

Quantitative Analysis of Nanorough Hydrogenated Si(111) Surfaces through Vibrational Spectral Assignment by Periodic DFT Calculations br

Mitigating Plasmonic Absorption Losses at Rear Electrodes in High‐Efficiency Silicon Solar Cells Using Dopant‐Free Contact Stacks

Amorphous silicon passivated contacts for diffused junction silicon solar cells

Zinc tin oxide as high-temperature stable recombination layer for mesoscopic perovskite/silicon monolithic tandem solar cells

Amorphous/Crystalline Silicon Interface Stability: Correlation between Infrared Spectroscopy and Electronic Passivation Properties

Improved amorphous/crystalline silicon interface passivation by hydrogen plasma treatment

Modification of textured silicon wafer surface morphology for fabrication of heterojunction solar cell with open circuit voltage over 700mV

Understanding of passivation mechanism in heterojunction c-Si solar cells

Below the Urbach Edge: Solar Cell Loss Analysis Based on Full External Quantum Efficiency Spectra

Amorphous silicon enhanced metal-insulator-semiconductor contacts for silicon solar cells

Back-Contacted Silicon Heterojunction Solar Cells With Efficiency >21%

Sputtered rear electrode with broadband transparency for perovskite solar cells

Nanocrystalline Silicon Carrier Collectors for Silicon Heterojunction Solar Cells and Impact on Low-Temperature Device Characteristics

Interdigitated back contact silicon heterojunction solar cells featuring an interband tunnel junction enabling simplified processing

Amorphous/crystalline silicon interface defects induced by hydrogen plasma treatments