System and method for cathodoluminescence-based semiconductor wafer defect inspection

An apparatus comprising:

• an electron beam source configured to generate an electron beam;
• a sample stage configured to secure a sample;
• an electron-optical column including a set of electron-optical elements to direct at least a portion of the electron beam onto a portion of the sample;
• a set of guide optics located at a position within or below the electron-optical column, wherein the set of guide optics comprises a first coaxial mirror and a second coaxial mirror, wherein the first coaxial mirror is configured to receive cathodoluminescent light from the sample and direct the cathodoluminescent light to the second coaxial mirror;
• a set of collection optics, wherein the set of guide optics is configured to direct the cathodoluminescent light collected from the sample to the set of collection optics;
• and
• a detector, wherein the set of collection optics is configured to image the cathodoluminescent light onto the detector.