Fast in-line surface topography metrology enabling stress calculation for solar cell manufacturing for throughput in excess of 2000 wafers per hour

We present a novel structured pattern projection tool for stress, and topography measurement of solar cells. The presented tool has expanded (two standard deviations) accuracy and repeatability of 0.5 mm, exceeding current industry requirements (±0.05 mm one standard deviation). Measurements on the R&D system indicate that this technology is capable of performing measurements with a throughput exceeding 2000 wafers per hour.