Navigation Links
How to produce flexible CIGS solar cells with record efficiency
Date:9/21/2011

This release is available in German.

High-performance flexible and lightweight solar cells, say, on plastic foils, have excellent potential to lower the manufacturing costs through roll-to-roll processing and the so called "balance-of-system" cost, thus enabling affordable solar electricity in the near future. Thus far, however, flexible solar cells on polymer films have been lacking behind in performance compared to rigid cells, primarily because polymer films require much lower temperatures during deposition of the absorber layer, generally resulting in much lower efficiencies.

Record-breaking team

The research team at Empa's Laboratory for Thin Film and Photovoltaics, led by Ayodhya N. Tiwari, has been involved in the development of high-efficiency CIGS solar cells on both glass and flexible substrates with a special focus on reducing the deposition temperature of the CIGS layer. The group has repeatedly increased efficiency of flexible CIGS solar cells over the past years first at ETH Zurich and now since three years at Empa. With their current record value of 18.7% Tiwari and his team nearly closed the efficiency gap to cells based on multi-crystalline silicon (Si) wafers or CIGS cells on glass. The scientific details of their novel low-temperature deposition technology and the multi-layered device have recently been published in Nature Materials.

"To achieve such high efficiency values, we had to reduce the recombination losses of photo-generated charge carriers", said Tiwari. CIGS layers grown by co-evaporation at temperature of around 450 C have a strong composition grading because of inadequate inter-diffusion of intermediate phases and preferential diffusion of gallium (Ga) towards the electrical back contact.

To overcome this problem doctoral students Adrian Chirilă and Patrick Bloesch developed novel processes for optimizing the solar cell performance. To achieve an appropriate composition profile in the CIGS layer for enabling more efficient charge carrier collection and reduced interface recombination Chirilă and colleagues developed an innovative growth process by carefully controlling the Ga and indium (In) evaporation flux during different stages of the evaporation process.

High-efficiency solar cells grown on cheap metal-foils

Such high-efficiency CIGS solar cells up to now were developed only on glass substrates with processes where CIGS layers are grown at temperatures of 600 C or above. In contrast, polymer foils cannot withstand such high temperatures. The low-temperature process now developed by Tiwari and Co. not only yielded an 18.7%-efficiency cell on polymer foils but also another record efficiency of 17.7% on steel foil without any diffusion oxide or nitride barrier layer commonly used in high-temperature processes. Both efficiencies were independently certified by the Fraunhofer Institute for Solar Energy Systems (ISE) in Freiburg, Germany. "We have thus shown that this low-temperature process is also applicable on low-cost metal foils such as aluminum or Mild-steel, achieving comparably high-efficiency cells and indicating a severe cost reduction potential with this technology", said Tiwari.

Scientists at FLISOM, a start-up company, and Empa have been collaborating to further develop low-temperature processing, and FLISOM is scaling up the technology for roll-to-roll manufacturing of monolithically interconnected solar modules and commercializing the technology. The research has been supported by the Swiss National Science Foundation (SNSF), the Commission for Technology and Innovation (CTI), the Swiss Federal Office of Energy (SFOE), EU Framework Programmes as well as by Swiss companies W. Blsch AG and FLISOM.


'/>"/>

Contact: Dr. Ayodhya N. Tiwari
ayodhya.tiwari@empa.ch
41-587-654-130
Swiss Federal Laboratories for Materials Science and Technology (EMPA)
Source:Eurekalert  

Related biology technology :

1. Neuroscientists produce guide for ultrasound use to treat brain disorders in clinical emergencies
2. Researchers produce detailed map of gene activity in mouse brain
3. Piezoelectric nanowires allow electrical signals to be produced from mechanical actions
4. Natural gas produced from fine milling of precious metals
5. Northern Illinois University scientists find simple way to produce graphene
6. Pixantrone in Combination with Fludarabine, Dexamethasone and Rituximab Produces High Rates of Complete Remissions in Patients with Relapsed or Refractory Indolent Non-Hodgkins Lymphoma
7. The Revelation of Man: A New Novel That Explains The Enduring Survival and Existence of Homosexuals If They Dont Naturally Reproduce
8. Optical microscope without lenses produces high-resolution 3-D images on a chip
9. UC San Diego chemists produce first high-resolution RNA nano square
10. Templated growth technique produces graphene nanoribbons with metallic properties
11. Cellectis and the Etablissement Francais du Sang Launch StemRed, a Program to Produce Red Blood Cells From Stem Cells
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
How to produce flexible CIGS solar cells with record efficiency
(Date:8/11/2017)... ROCKVILLE, Md. , Aug. 11, 2017 ... in a New York Times article regarding ... 9.2 billion, according to Kalorama Information.  The ... an App for That"  used information ... Remote Patient Monitoring & Telemedicine Market  (Sleep, ...
(Date:8/10/2017)... (PRWEB) , ... August 09, 2017 , ... ... the classroom next week-- as students. From August 14th through the 16th, the ... institute, which debuted in the summer of 2016, provides Philadelphia-based middle school educators ...
(Date:8/10/2017)... ... August 10, 2017 , ... DrugDev and ... webinar to demonstrate how Good Clinical Practice (GCP) can be used throughout ... addition the webinar will discuss the importance of GCP compliance, how sites are affected ...
(Date:8/8/2017)... ... August 08, 2017 , ... HumanZyme ... in human cells, today announced the launch of HumanKine® Interferon beta ... I family of interferons that activate Th1-type innate immune responses against viral and bacterial ...
Breaking Biology Technology:
(Date:4/5/2017)... , April 5, 2017  The Allen Institute for ... Cell Explorer: a one-of-a-kind portal and dynamic digital window ... imaging data, the first application of deep learning to ... stem cell lines and a growing suite of powerful ... for these and future publicly available resources created and ...
(Date:4/5/2017)... -- KEY FINDINGS The global market for ... of 25.76% during the forecast period of 2017-2025. The ... the growth of the stem cell market. ... INSIGHTS The global stem cell market is segmented on ... stem cell market of the product is segmented into ...
(Date:4/3/2017)... , April 3, 2017  Data captured ... engineering platform, detected a statistically significant association ... prior to treatment and objective response of ... potential to predict whether cancer patients will ... treatment, as well as to improve both pre-infusion ...
Breaking Biology News(10 mins):