Wafer level testing for semiconductor laser manufacture via spatially resolved photoluminescence

High bandwidth telecommunications depends on the efficient manufacture of semiconductor lasers. The quality of partially processed laser structures can be monitored at the wafer level by spatially resolved photoluminescence (SRPL), providing timely feedback to processing engineers. The same testing procedure can also be applied at the chip level. This allows comparisons of wafer level material quality, chip level material quality, and chip performance.