The laboratory of photovoltaics and thin-films electronics (PV-lab) of IEM, founded in 1984 by Prof. Arvind Shah and headed by Prof. Christophe Ballif since 2004, has pioneered several new processes for the preparation of thin-film silicon, such as the introduction of very high frequency (VHF) plasma deposition and microcrystalline silicon as an efficient photovoltaic material, and simple processing of heterojunction crystalline cells. Current activities of the laboratory cover a broad spectrum, ranging from fundamental research to industrial technology transfer. The lab masters processes of device fabrication for a wide variety of transparent conductive oxides, thin-film solar cells and high-efficiency crystalline silicon solar cells. It also has expertise for specialty detectors. It has full facilities for packaging of PV products. It has been designated as a center of national importance by the Swiss Federal Office for Energy.

PV-lab is a founding partner of the CSEM PV-center, which started operation in 2013 with a focus on technology transfer, and industrialisation of technologies.


© 2022 Deniz Türkay

Two new world records on perovskite/silicon tandem solar cells

— For the first time, an efficiency of 30% for perovskite-on-silicon-tandem solar cells has been exceeded thanks to a joint effort led by scientists at EPFL’s Photovoltaics and Thin Film Electronics Laboratory in partnership with the renowned innovation center, CSEM. Independently certified by the National Renewable Energy Laboratory (NREL) in the United States, these results are a boost to high-efficiency photovoltaics (PV) and pave the way toward even more competitive solar electricity generation. 

© 2022 EPFL

SOPHIA Workshop and PV Recycling Workshop

— SOPHIA Workshop and Workshop of the project ReSi-Norm – Standardization of Recycling Processes for Silicon Solar Modules

© 2022 Mise au point - RTS

Discover the video and interview of Christophe Ballif

— RTS Mise au point – EPFL and CSEM on Instagram and Facebook: Advanced PV research and relationship to Europe

EPFL scientists in Neuchâtel have developed a tandem solar cell that can deliver a certified efficiency of 29.2%. © Christian Wolff / EPFL

Improving the efficiency of tandem solar cells

— EPFL scientists in Neuchâtel have developed a tandem solar cell that can deliver a certified efficiency of 29.2%. This achievement was made possible by combining a perovskite solar cell with a textured silicon solar cell.

© 2022 Nature Review Materials

A comprehensive review just published in Nature Review Materials

— A comprehensive review just published in Nature Review Materials: all you want to know about crystalline silicon, past, present and future.

© 2021 EPFL

International workshop on Silicon Heterojunction organized by CSEM

— 4th International workshop on Silicon Heterojunction solar cells will be hosted by CSEM (remotely) on 09-10 November 2021 

© 2021 EPFL

Poster awards for PVLAB and CSEM at the national PV congress

— PVLAB member Jordan Holweger got a poster award at the Swissolar national PV congress in Bern from 1 to 2 July 2021. The poster advertises a simple and effective heat pump control algorithm for PV applications. The CSEM team lead by Christophe Ballif also got a poster award for their work on back-contacted silicon heterojunction solar cells and modules.

© 2021 Springer, illustration from Michael Meier on p. vi

NEW Book on Solar Cells and Modules.

— NEW Book on Solar Cells and Modules edited by Arvind Shah, the funder of the PV-LAB with contribution of Christophe Ballif and Alessandro Virtuani. 

© 2020 EPFL

ECOplay: the mobile application that helps you save energy

— ECOplay, the mobile application that helps you save energy, is available for free download – for iOS and Android smartphones. The application aims to help people change certain small daily energy habits that can make a difference from a financial and environmental perspective. The ECOplay was developed in the framework of the European project FEEdBACk, where the Photovoltaics Laboratory (PV-LAB) at École Polytechnique Fédérale de Lausanne (EPFL) has led the development of the energy monitoring, forecasting, and optimization algorithms embedded in the app.

© 2020 Elsevier

Two new papers on “high temperature passivating contacts”

— PV-lab realized two new paper on passivating contacts. Frank Meyer and his co-author show a new selective layer with low temperature process while Philippe Wyss and co-author show a p-type rear selective contact layer that is compatible that doesn't degrade during high temperature process.

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Three-dimensional in situ imaging of single-grain growth in polycrystalline In2O3:Zr films

D. Dzhigaev; Y. Smirnov; P-A. Repecaud; L. A. B. Marcal; G. Fevola et al. 

Communications Materials. 2022-06-17. Vol. 3, num. 1, p. 38. DOI : 10.1038/s43246-022-00260-4.

A 3D indicator for guiding AI applications in the energy sector

H. Quest; M. Cauz; F. Heymann; C. Rod; L. Perret et al. 

Energy and AI. 2022-05-20. Vol. 9, p. 1-13, 100167. DOI : 10.1016/j.egyai.2022.100167.

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

J. Holovsky; J. Sebera; V. Sychrovsky; J. Zemen; S. De Wolf et al. 

Journal Of Physical Chemistry C. 2022-05-19. Vol. 126, num. 19, p. 8278-8286. DOI : 10.1021/acs.jpcc.1c09766.

Calibration of ground surface albedo models

A. Tuomiranta; P-J. Alet; C. Ballif; H. Ghedira 

Solar Energy. 2022-05-01. Vol. 237, p. 239-252. DOI : 10.1016/j.solener.2022.03.047.

Impact of rapid thermal processing on bulk and surface recombination mechanisms in FZ silicon with fired passivating contacts

Haug; S. Libraro; M. Lehmann; A. Morisset; A. Ingenito et al. 

Solar Energy Materials And Solar Cells. 2022-05-01. Vol. 238, p. 111647. DOI : 10.1016/j.solmat.2022.111647.

In Situ Reflectometry and Diffraction Investigation of the Multiscale Structure of p-Type Polysilicon Passivating Contacts for c-Si Solar Cells

A. Morisset; T. Famprikis; F-J. Haug; A. Ingenito; C. Ballif et al. 

Acs Applied Materials & Interfaces. 2022-04-13. Vol. 14, num. 14, p. 16413-16423. DOI : 10.1021/acsami.2c01225.

Bulk Defects and Hydrogenation Kinetics in Crystalline Silicon Solar Cells With Fired Passivating Contacts

M. Lehmann; A. Desthieux; N. Valle; A. Morisset; P. Wyss et al. 

Ieee Journal Of Photovoltaics. 2022-04-11. Vol. 12, num. 3, p. 711-721. DOI : 10.1109/JPHOTOV.2022.3161871.

Monolithic Perovskite-Silicon Tandem Solar Cells: From the Lab to Fab?

F. Fu; J. Li; T. C-J. Yang; H. Liang; A. Faes et al. 

Advanced Materials. 2022-04-07.  p. 2106540. DOI : 10.1002/adma.202106540.

Testing of planar hydrogenated amorphous silicon sensors with charge selective contacts for the construction of 3D-detectors

M. Menichelli; M. Bizzarri; M. Boscardin; M. Caprai; A. Caricato et al. 

Journal of Instrumentation. 2022-03-18. Vol. 17, num. 03, p. C03033. DOI : 10.1088/1748-0221/17/03/C03033.

Single photon detection with amorphous silicon-based microchannel plates: A Monte Carlo model

J. Löffler; J. Thomet; S. Frey; C. Ballif; N. Wyrsch 

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 2022-03-17. Vol. 1032, p. 166589. DOI : 10.1016/j.nima.2022.166589.