ThinSi

FP7 project: Thin Si film based hybrid solar cells on low-cost Si substrates.

Work programme topic addressed: Efficiency and material issues for thin-film photovoltaics. 

Concept of the solution: The concept of crystalline silicon thin-film solar cells on low-purity substrates will substantially reduce the consumption of high-purity silicon material and has at the same time potential to reach high efficiencies comparable to wafer silicon solar cells.

Scope of the project is: The main vision of ThinSi is to develop a solar cell process chain for high throughput, cost-effective manufacturing of thin Si based solar cells on low-cost Si substrates. A set of innovative technological processes will be developed to realise this new concept and transfer the results into production.

NT-MDT was selected as industrial partner to support this project with development of new analytical tool: integrated SPM-Ellipsometer system.

The main tasks attributed and previous experiences
NT-MDT will contribute strongly to WP3 by providing analysis results and developing a new system for thin film and solar cell characterisation.
NT-MDT will develop and bring to Europen market special analytical equipment which will allow making a monitoring of electrical and structural properties of individual solar cell materials and interfaces based on Atomic Force Microscopy (AFM) and Spectral Optical methods and instruments for solar cell processing on nanoscale level: AFM/SNOM/CONFOCAL/RAMAN/ELLYPSOMETRY combined measurement tool.
Combination of extended AFM techniques with conventional optical methods like Raman, Photoluminescence and Confocal microscopy/spectroscopy realizes the possibilities to develop a unique tool for a principal new investigation of such materials.
The quantity of modes as Topography, Kelvin Probe Imaging, Scanning Capacitance Imaging, Spreading Resistance (Local Conductivity) Imaging, Electrical Force Microscopy, Local Electrical AFM Spectroscopy and Raman Confocal Imaging/Mapping applied simultaneously within one measurement pass in investigations of the electrical properties of the solar cells active layers and electrical processes on the interfaces between layers gives a sufficient understanding of the nano- properties and processes.
So the important existing properties are the electrical state density, local conductivity, concentration of the electrical charge carriers, Work Function values of the active layers and electrical barriers of the layer interfaces, optically active areas and of cause the quality and structural defects of the active layers. Also in supposed investigations we make a focus of the nano/micro photovoltaic properties e.g. in-situ electrical transport of electrical charge carriers in silicon layers and interfaces under the light illumination in the c-Si thin-film solar cells processing.
NT-MDT Co. has a history of cooperation on the European level e.g. participation in the FP6 project NANOSPIN. Within this project was we developed a new AFM tool for characterisation of magnetic domain structures on magnetic nanoparticles and structures.