Product Briefing Outline: The alpha500 from WITec is an automated microscope system combining Confocal Raman Microscopy for chemical 3-D imaging and Atomic Force Microscopy for high resolution structural surface imaging which allows comprehensive characterization of various solar cell materials on the nano- and micrometer scale.
Problem: In the research and development of photovoltaic devices, the primary goals are to increase the conversion efficiency of the solar cells or to improve and monitor the production process. For these studies, a detailed knowledge of the micro- and nanostructures along with the chemical properties is essential for further improvements.
Solution: Confocal Raman Imaging not only reveals optical information but also information regarding the 3D distribution of the chemical compounds, crystallinity and material stress. Atomic Force Microscopy additionally allows characterization of surface structures on the nanometer scale. The WITec alpha500 is the first instrument on the market to combine Confocal Raman Microscopy for 3-D chemical imaging and AFM for high resolution structural imaging in an automated system for large samples. A motorized sample stage with a travel range of 150×100 mm (350×300 optional) makes possible multi-area/multi-point measurements or overview scans on an arbitrary, user-defined number of measurement points. Specific automated functions such as an integrated auto-focus and an automatic AFM-tip approach guarantee standardized routine measurement procedures or individually defined sequences to be performed without any online process control by an operator during the measurement. The modular design even provides upgrade possibilities for the investigation of very large samples such as complete PV modules for offline process control. An optimized optical system design allows for ultrafast Raman Imaging or very low Raman signal detection. Raman spectroscopy and imaging are nondestructive techniques delivering information on various material properties such as crystallinity, material stress, stoichiometry, material distribution, homogeneity or clustering. The confocal microscope setup allows it to perform depth profiles in order to acquire information on the layering of thin films.
Applications: CIS & CIGS thin films, Si-Solar cells, ZNO, Dye Solar Cells.
Platform: The alpha500 is controlled by the fully digital WITec control unit alphaControl and the WITec Control software. For automated multi-point measurements on large samples the software provides features in order to manually predefine the sample positions or to import existing coordinates.
Availability: Currently available.