30 November 2010

LayTec adds color measurement to SolR thin-film PV monitoring tool

LayTec GmbH of Berlin, Germany (which provides in-situ optical metrology systems for thin-film processes) says that, in addition to measuring the precise film thickness of all layers throughout the solar cell manufacturing process, its SolR system can now monitor the following photovoltaic (PV) cell features in-line: texture and surface roughness and — in the case of transparent conducting oxide (TCO) — conductivity. The new feature now allows determination of the precise color value of the layer surface.

Image: CIGS reflectance spectrum and CIEXYZ color space.

LayTec says that, after a deposition step, it is often possible to anticipate by visual inspection if the coating was performed successfully and if the solar module will meet the color spaces. But this process can now be objectified using the SolR. The real-time analysis software transforms the reflection spectra into a color space model. Available models are RGB, CIEXYZ or CIELAB color spaces. In either model the color is represented by a data triple. Slight variations in surface color can indicate deviations in stoichiometry or other detrimental effects. The Figure shows the reflectance spectrum of a CuInSe2 absorber layer in a copper indium diselenide (CIGS) thin-film PV cell and the representation of the typical grey-bluish color in the CIEXYZ color space.

In contrast to human visual inspection, color measurement can be performed in narrow spaces and in a variety of atmospheres and vacuum, says LayTec. The new feature can hence lead to a new level of quality control in solar cell production, the firm claims.

* LayTec says that (since October) Hyun Lee is a new team member in its R&D department, responsible for pre-production series and replenishment planning for the firm’s PV section. Hyun graduated as an engineer in physical techniques at the Rhein-Main University of Applied Sciences, from which he already has experience in optics and sensor systems.

Picture: Hyun Lee.

In addition, a position is currently open in the firm’s PV section for an experimental physicist.

See: LayTec Company Profile

Tags: LayTec SolR

Visit: www.laytec.de/careers.html