Micro photoluminescence imaging

A system comprising:

• one or more light sources configured to continuously illuminate a wafer comprising a semiconductor-dielectric interface with excitation light having a wavelength and intensity sufficient to induce photoluminescence in the wafer and having an intensity sufficiently low such that Auger recombination does not substantially occur in the portion of the wafer;
• a first detector configured to detect photoluminescence emitted from the wafer in response to the illumination over a period during which the wafer is continuously illuminated, the detector integrating the detected intensity over the period;
• a second detector configured to detect excitation light reflected from the wafer;
• and
• one or more processors configured to:
• compare the detected photoluminescence from the wafer and the detected excitation light reflected from the wafer;
• and
• assess a passivation of the semiconductor-dielectric interface based on the comparison.