University Unveils Sensitive Microscope for Chip Inspection

A technician at Heriot-Watt University in Edinburgh, UK, has built a microscope powerful enough to monitor the inner workings of semiconductor chips.

Lynn Edwards, in collaboration with Gerald S. Buller, a researcher at the university, constructed a time-resolved photoluminescence microscope that fires laser beams at the chips and measures the resulting photoluminescence. Each optical component in the microscope is centered in cylindrical holders that are placed on a machined slot. Unlike many traditional microscopes, the optics, lasers, detectors and camera revolve around a sample for minimal vibration.

The team incorporated diode lasers from Hamamatsu Corp., and single-photon avalanche diodes measured the resulting photoluminescence between 420 and 1550 nm, a range suitable for both wide-gap and narrow-gap semiconductors. The device will be used for research, but Buller said he hopes it can be made available to commercial manufacturers in the future.