METHOD FOR MEASURING LIFETIME OF CHARGE CARRIERS IN SILICON Russian patent published in 2002 - IPC

FIELD: metrology; production of semiconductor silicon ingots. SUBSTANCE: method involves pre-measurement treatment of part to be metered, illumination of part surface with pulsed pumping beam to build up redundant quantity of charge carriers and with continuous testing radiation with wavelengths grater than that of pulsed pumping beam; then areas of pulsed pumping beam and testing radiation are intersected inside part under measurement, testing radiation passed through part is received, intensity of testing radiation coming from part as function of time is recorded, lifetime of charge carriers is computed using measured time function, then volume of part under measurement is scanned by mentioned intersection area, and charge carrier lifetime is determined for scanned areas; part chosen for measurement is grown silicon ingot; wavelength of pulsed pumping beam used for illumination is 1.15-1.28 mcm; then exit of point of pulsed pumping beam from part under measurement is recorded and used to determine path of pulsed pumping beam inside part. Method provides for conducting nondestructive proximate X-ray diagnosis of the lifetime of charge carriers in silicon ingots of actually any size at the same time eliminating detrimental influence of recombination surfaces on measurement results and requiring no thorough pre-measurement procedures. EFFECT: improved measurement accuracy. 4 cl, 4 dwg, 4 ex