The Boeing Company
Active real-time characterization system for detecting physical imperfections during semiconductor manufacturing

Abstract:

An active real-time characterization system for detecting unwanted elements and/or physical imperfections on a semiconductor wafer during manufacturing. Infrared and visible light sources output beams of coherent light directed at a particular area on the semiconductor wafer via associated polarizing control elements. A series of cameras, including a visible light camera, a visible light second harmonic generation camera, an infrared camera, an infrared second harmonic generation camera, a sum-frequency camera and a third-order camera are configured to receive return beams of light via associated polarizing control elements. The polarizing control elements include a polarizer, a quarter wave plate and/or a half wave plate. A processor processes the signals received from the cameras to detect unwanted elements and/or physical imperfections on the semiconductor wafer.