| 摘要 |
PURPOSE:To detect defect and so on by a method wherein an excited light intensity- modulated at a specific frequency is irradiated on a semiconductor sample to generate the fluctuations in a periodic electric field in the semiconductor sample and a component only of the specific frequency of the fluctuations of electrode potential of the electrode is retrieval by the phase detector. CONSTITUTION:An excited light A emitted from an excitation light source 1 is intensity modulated at a proper specific frequency by such an optical modulator 2 as a mechanical chopper and thereafter, the excited light is focussed and irradiated on a measurement place of a semiconductor sample 4 through a condensing system 3. Excess charge carriers are produced in the semiconductor sample 4 at a period corresponding to a specific optical intensity modulated frequency and the excess charge carriers make fluctuations in a periodic electric field generate on the periphery of the measurement place as being unequally distributed in the sample. This semiconductor sample 4 is placed on a metal electrode 6 through such an insulating film 5 as an organic thin film and the fluctuations of the electric field due to the irradiation of the excited light are detected as the fluctuations of electrode potential of the electrode 6. This fluctuating output is inputted to a phase detector 7 and a component only of the same frequency s the specific excited light intensity modulated frequency is retrieved and measured.
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