Rapid mapping of AR coating thickness on Si solar cells using GT-FabScan 6000

A new technique for rapid mapping of the thickness, of an antireflection (AR) coating on a solar cell is described. A filtered, reflectance (intensity) image of the AR-coated wafer is generated by a CCD camera mounted on a GTFabScan. This image is converted into a thickness image using a transformation relating local AR thickness to the local intensity in the image plane. The thickness map is generated in <100 ms.