Method and apparatus for performing heterodyne lock-in imaging and quantitative non-contact measurements of electrical properties
OwnerAndreas MANDELIS, Alexander Melnikovinventors
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OwnerAndreas MANDELIS, Alexander Melnikovinventors
Estimating the term…
Methods are provided for producing optical carrierographic images of a semiconductor sample. Focused and spatially overlapped optical beams excite carriers across within the semiconductor sample, where the optical beams are modulated such that a beat frequency is substantially less than either modulation frequency. An infrared detector detects infrared radiation emitted from the semiconductor sample in response to absorption of the optical beams, thereby obtaining a plurality of carrierographic signals at different points in time during at least one beat period, which are processed with a lock-in amplifier, with a reference signal at the beat frequency, to obtain an amplitude signal and a phase signal. Carrierographic lock-in images of the sample are obtained in a scanning configuration, or in an imaging format using an imaging detector. The images carry quantitative information about recombination lifetimes in substrate Si wafers and electrical parameters in solar cells, namely photogeneration current density, diode saturation current density, ideality factor, and maximum power photovoltage.
A method of producing an optical carrierographic image of a semiconductor sample, the method comprising:
A method of measuring the effective lifetime of carriers in a semiconductor substrate using lock-in-carrierography, the method comprising:
A method of optically measuring one or more electrical parameters of a solar cell using lock-in-carrierography, the method comprising:
Dependencies are inferred from the claim text.