Institut Photovoltaïque d’Île-de-France

FOUNDING MEMBERS

November 2019

Editorial

Dear colleagues, We are glad to introduce this second IPVF newsletter!

Total is a historical partner of IPVF, from the crea-tion of the ‘Institut pour la Transition Energétique’ to the installation in the building and the execution of the IPVF research program. Since 2014, IPVF has grown and has demonstrated its capability to reach operational and scientific excellence.

IPVF and its partners have been doing an excellent job to develop the next generation of high efficiency PV cells that will contribute to promote the gener-ation of low carbon electricity. The flexible and ad-vanced technology platform, the unique technical competencies available at IPVF and its location on the Saclay Campus make IPVF a unique asset in the French research landscape and for its industrial partners to develop new and innovative solutions for the energy transition. Today, the PV landscape and competitive market have drastically changed, which is now challenging the IPVF roadmap and is a driver for an evolution of IPVF to adapt to these changes. As an institute for the energy transition, we think that IPVF’s mission is to be instrumental on photovoltaics but also on relevant low carbon energy-related topics, such as technological solu-tions to reduce CO2 emission. Total is now mobi-lized to assist and accelerate this transformation to strengthen the position of IPVF ITE by leveraging these assets while widening the scope of activities.

In this context solar technologies are of course of paramount importance. We can even go further than only generating electrons from photons but also producing molecules of interests. That is the sense of the new program “solar to fuels” we pro-mote and are engaging in. We can notably imagine reducing CO2 into fuels which would constitute a virtuous loop and would answer to a major stake for our future. So, after converting solar energy into electrical energy, the next step consists in con-verting the electrical energy into chemical energy as efficiently as possible to open a new chemis-

For a very long time, III-V photovoltaics have been at the forefront of high-efficiency solar cells, demonstrating their numerous advantages to overcome the Shockley-Queisser limit and to explore new concepts (heterostructures, localized/selective/passivated contacts, new characterization methods,…). The ambition of the III-V program at IPVF is to develop low cost III-V materials and technologies for III-V/Si tandem solar cells. It focuses on new routes toward low-cost processes (transfer of III-V layers, bonding,…), and new epitaxial growth methods (low temperature, high pressure, direct growth on Si,…). Beyond these projects, III-V is also a technology of choice to test and validate new experimental setups, simulation models, advanced concepts and architectures. In this regard, the III-V program is strongly linked to the whole scientific program at IPVF.

Low-cost III-V for tandem on Si solar cells

Newsletter

try route based upon CO2! In a first step, thanks to the photoelectrochemistry, we can expect reducing water into hydrogen. This e-H2 will constitute a key molecule in the future, being : a fuel, an energy storage solution and an energy vector, but also a reductive agent to decompose CO2 into fuels such as methanol. We can then also consider converting directly CO2 into fuels via a tailored PEC (photo-electrochemical) cell. The field of possi-

bilities is large. Thanks to the combined expertise on solar cell technologies, ad-vanced characterization techniques and thin films, IPVF can legitimately address this technology challenge to develop competitive PEC cells within the next 3 years : making the possible a reality!

Périne Jaffrennou & David Aymé-Perrot

NewsletterInstitut Photovoltaïque d’Île-de-France

Editorial board: Pere Roca i Cabarrocas, Roch Drozdowski-Strehl, Christophe Bonelli,Lars Oberbeck, Jean Rousset, Jean-Paul Kleider, Philippe Schulz, Stéphane Collin, David Aymé Perrot, Jean-François Guillemoles

Périne & David

Highligths from the Research program

Advanced carrier temperature determination for hot carrier solar cell applicationsQuantum-well structures are one of the promising candidates for hot carrier solar cell applications. One practical technique to study hot carrier properties of such structures is to perform photoluminescence spectroscopy and to extract carrier temperature via fitting the experimental results with the generalized Planck’s law. However, determination of carrier temperature in nano-structures is challenging and it requires considering the contribution of band-filling effects and transitions from higher (discrete) energy levels. We have successfully performed modeling for photoluminescence spectra to extract carrier temperature for InxGa1-xAs/InyGa1-yAszP1-z multi-quantum-well hot carrier absorbers and to determine their thermalisation coefficients. We have recently presented the results at the Hot Carrier Focus Workshop in Munich, Germany, and at the NextPV Conference in Tokyo, Japan.Contact: Jean-François GUILLEMOLES • jf.guillemoles@chimie-paristech.fr

Light-induced passivation in triple cation halide perovskitesThe combined effects of light and atmosphere on triple cation perovskite thin films were investigated. We employed advanced and complementary characterization techniques, namely multidimensional absolute photoluminescence (PL) and X-Ray Photoelectron Spectroscopy (XPS), to correlate optoelectronic and chemical properties. Through hyperspectral imaging (HI) and time-resolved fluorescence imaging (TR-FLIM) we investigated intrinsic material and carrier transport properties with quantitative indicators such as Quasi Fermi Level Splitting (QFLS), carrier mobility and recombination rates. These results have been presented at IUPAC World chemistry Congress 2019 in Paris and will be presented at Kaust Workshop “Emerging concept in solar energy conversion “ in Saudi Arabia.Contact: Stefania CACOVICH • stefaniacacovich@gmail.com

Assessing transport properties in low lifetime semiconductorsHigh frequency modulated photoluminescence (HF-MPL) and pulsed transient PL (TRPL) were performed on passivated n-doped InP wafer with doping density of 3 × 1018 cm-3. Figure 1a shows that the fitted values for surface recombination velocity Sfront=5e4 cm/s and bulk lifetime τbulk=10 ns match well the variation of phase for illumination power from 1.4e17 photon/cm²/s up to 1.4e20 photon/cm²/s. Figure 1b shows that the TRPL decays can be fitted very well also with barely different values of Sfront and τbulk. These coherent results validate our original high-frequency MPL setup designed to assess the transport properties in low lifetime semi-conductors on the one hand and helps analysing the passivation properties of the layers designed by ILV on the other hand. This work will be presented at JNPV 2019. Contacts: Wei ZHAO • wei.zhao@ipvf.fr and Baptiste BERENGUIER • baptiste.berenguier@cnrs.fr

XPS chemical analysis of perovskite layers: evaluation of usual Ar+ bombardment capabilities for depth profiling and UHV stability of halide perovskites XPS depth profiling (Fig.1) of triple cation halide perovskite Cs0.05(MA0.17FA0.83)0.95Pb(I0.83Br0.17)3 has been realized up to the TiO2 transport layer by conventional Ar+ bombardment (1000 eV). The I, Pb, Cs and C contents in depth are relatively stable, a global N decrease over bulk and a Br accumulation at the perovskite/TiO2 interface are observed in agreement with FA, MA, Cs perovskites layers profiles presented in the literature. So, the feasibility of halide perovskite XPS profiling is demonstrated. In addition, the stability of the perovskite layer under ultra-high vacuum (Fig. 2) has been evaluated after 6 days storage in the spectrometer (in dark). The comparison between the chemical composition of the perovskite surface at start (t=0) and after 6 days in the analysis chamber has shown a slight variation mainly due to the superficial carbon content. The next step will be the control of the reproducibility and reliability of the chemical information especially in terms of chemical environment. The use of polyatomic bombardment will be explored. Several parameters such as the Arn

+ cluster size and energy will be tested to obtain more accurate composition profiles but also the impact of this physical treatment on the surface properties will be studied in the frame of an internship planned for 2020. Contact: Muriel BOUTEMY • muriel.bouttemy@uvsq.fr and Davina Messou • davina.messou@ipvf.fr

Fig 1. a) Evolution of the absolute PL signal at different ageing timeS (1 different sample for each ageing time) b) Averaged experimental PL spectra and correspon-ding fitting. c) Correlation between QFLS and Energy Gap.

IPVF has decided to strengthen the team in charge of Research equipment by creating a new function in the organizational chart: Equipment Division Manager (EDM).The main role of the EDM is to support the projects by managing the supply,

the procurement, maintenance, calibration and performance of equipment and services in accordance with IPVF strategies, policies and procedures. In November two EDMs have joined the group: Julie Goffard, in charge of all characterization tools (composition, morphological, optical and electrical) and Frederique Donsanti for all material fabrication under vacuum. At the interface between IPVF platform and IPVF program research, their mission is to provide all the platform’s power and expertise serving the research programs.

News from the platformEquipment Division Manager (EDM)

Frédérique Donsanti Julie Goffard

Did you know? IPVF is equipped with a Building Management System (BMS) which is a computer-based control system that controls and monitors the building’s mechanical and electrical equipment such as Heating, Ventilation, and Air Conditioning (HVAC), cooling water, ultra-pure water, lighting, power systems, fire systems, and security systems (access control, surveillance cameras). This system offers several benefits such as the ability to adjust the temperature, pressure and humidity of each laboratory room, control the energy consumed in the building and monitor operating or security alarms. This powerful system contributes to the performance of our Research Centre. With the Gas Control System (Air Liquide), it provides enhanced security to our operations.

Conctact: Destin GUERENGOMBA • destin.guerengomba@ipvf.fr

They allow the samples to be characterized between -196 ° C and 450 ° C with excellent stability. Max sample size 30mm x30mmx4mm. Contacts allow to connect the samples with 2 or 4 points. They are intended to be used in room 1LA.32 or 1LA.57.

Contact: Daniel ORY • daniel.ory@edf.fr

Building Management System

2 cryostats for PL and I (V) microscopy are operational.

view of supervision

The PERCISTAND project will begin in January 2020 for a period of 3 years. It has a funding of 5 million Euros. It brings together 12 partners: IMEC (coordinator), VITO and UHasselt in Belgium, TNO in the Netherlands, ZSW, KIT and NICE Solar in Germany, EMPA and Solaronix in Switzerland and CNRS-IPVF in France. Two research centers outside Europe are also associated, in Australia (ANU) and in the United States (NREL). The aim is to combine CIGS and perovskite thin-film technologies toward tandem configurations. CIGS will act as bottom cell and perovskite as top cell. The target efficiencies are 30% for cells and 25% for mini-modules. The success of this project would represent a breakthrough providing the possibility of ultralight, flexible and very efficient modules for new applications (BIPV, mobility). The CNRS-IPVF team, led by Daniel Lincot and Philip Schulz, is responsible for the sub-project of tandem cells integrated into two terminals.

Projet H2020-PERCISTAND (Development of all thin-film PERovskite on CIS TANDem photovoltaics)

Contact: Daniel LINCOT • Daniel.LINCOT@cnrs.frand Philip SCHULZ • Philip.schulz@cnrs.fr

November 6. Professor Nam-Gyu PARK Seminar on « The history of the birth of perovskite solar cell technology & the latest developments around record yields » https://www.ipvf.fr/prof-nam-gyu-park-live-from-ipvf/

Visitors

Damien Coutancier (AI, CNRS) won the poster prize Ti-doped ZnO thin films by Atomic Layer Deposition: growth mechanism study and influence of process parameters on material properties

Damien Coutancier, Olivier Fournier, Shanting Zhang, Simone Bernardini, Frédérique Donsanti, Nathanaelle Schneider.

Publications November 2019 “Annealing of Boron-Doped Hydrogenated Crystalline Silicon Grown at Low Temperature by PECVD”Marta Chrostowski, José Alvarez, Alessia Le Donne, Simona Binetti, and Pere Roca i Cabarrocas. Materials 2019, 12, 3795; doi:10.3390/ma12223795

Conferences to comeJNPV Dourdan3-6 December 2019http://jnpv.geeps.centralesupelec.fr/

SPIE Photonics1-6 February 2020, San Franciscohttps://spie.org/PWO/conferencedetails/pv-devices?SSO=1

Physics of Solar Cells: from basic principles to advanced characterization. Les Houches School of Physics, 1-6 March 2020https://sunlit-team.eu/pv-school-2020/

Symposium for celebrating the 200th anniversary of Edmond Becquerel birthday:24th of March 2020 at the Museum d’Histoire Naturelle, Paris. Contact: daniel.lincot@cnrs.fr

Oral presentations The annual RAFALD (Réseau Français des Acteurs de l’ALD, http://rafald.org/fr ) workshop took place in Toulouse on 2019,Nov 5-7th. IPVF was well represented (8 participants) and active : 0.5 day ALD tutorial for beginners, 2 oral presentations, 3 poster presentations.

IPVF was well represented (8 participants) and active: 0.5 day ALD tutorial for beginners, 2 oral presentations, 3 poster presentations.