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A Low-Complexity Hall-Based Measurement System Implementing a Dark/Illuminated Differential Estimator for
Bernardo Reyes-Durán1, Carlos Álvarez-Macías1, Lizbeth Salgado-Conrado2
1Tecnológico Nacional de México/Instituto Tecnológico de La Laguna, Torreón 27000, Coahuila, Mexico.
None:
A low-complexity Hall-based measurement system implementing a dark/illuminated differential estimator of the majority-carrier photoconductive response is assessed on n-type crystalline silicon wafers with contrasting doping concentrations. The setup combines a Van der Pauw configuration, permanent neodymium magnets, a characterized white LED source, and a source-measure unit to extract an apparent Hall-derived differential indicator-not a calibrated majority-carrier density-under dark and illuminated steady-state conditions. At 1.81mWcm-2, the lightly doped wafer (ND≈1014cm-3) shows a resolved response (Δσn,H=29.61±3.406mScm-1), reported as mean ± sample standard deviation from 15 dark/light cycles. The heavily doped wafer (ND≈1017cm-3) gives a nominal below-threshold response (Δσn,H=1.167±0.140mScm-1) from the same cycling protocol; it should be interpreted only as an unresolved trend-level indication because it lies below the instrumental detection threshold. The contrast is qualitatively consistent with the expected doping dependence, but no quantitative performance ratio is claimed for the heavily doped wafer. A Macdonald-Cuevas comparison is used only as a qualitative physical-consistency benchmark. No independent QSSPC, SSPC, μ-PCD, or carrier-resolved photo-Hall measurement was available for the same wafers; therefore, the system serves as a complementary low-cost screening tool for comparative trend analysis, not a replacement for calibrated photoconductance or photo-Hall techniques, and it does not constitute a new measurement principle.

