SWIR cameras for detecting wafer defects and cell efficiency

Application areas: micro cracks, pinholes, doping, dirt

Equipment Features: InGaAs short-wave infrared cameras that operate between 0.9 and 1.7 microns are ideal for inspecting silicon ingots and wafers, as the material is transparent beyond 1.2 microns. GoodrichSWI cameras can detect voids in the material before the ingots, bricks, and rods are cut into wafers to produce single or multicrystalline solar cells. The camera can also detect cracks hidden in unprocessed wafers, finished cells, or thin films by mapping pressure, which will be used to make solar panels. SWIR cameras can also detect cut marks on the reverse side of the wafer and/or defects in the crystalline material. In addition, by applying a forward bias to the cell to produce the photoelectric effect, the uniformity of solar cell efficiency and conversion efficiency can be measured using SWIR cameras. This helps improve the cell manufacturing process and helps match cells of similar efficiency and assemble them into modules.