For various silicon wafer processing and device manufacturing processes, measurements of carrier lifetimes* are growing increasingly important in research and analysis related to metallic contamination and crystal defects. The silicon ingot lifetime measurement system manufactured by Napson Corporation incorporates Sugawara strobes to ensure consistent lifetime measurement meeting rigorous measurement standards.
* The term lifetime refers to the series of phenomena whereby illuminating a silicon ingot with a strobe temporarily increases the number of carriers (positive or negative electrons), after which carrier numbers decline with time, returning to their original state. P-type silicon crystalline bodies normally have large numbers of positive electrons, whereas N-type crystalline bodies have more negative electrons. It is known that strobe flash illumination increases the number of negative electrons (and positive electrons for the N type), which combine to return to the original state.