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Updated: Jun 17, 2026

Fabrication of Flexible Image Sensor Based on Lateral NIPIN Phototransistors
Published on: June 23, 2018
Ultra-high responsivity 4H-SiC floating-base phototransistors enabled by punch-through induced barrier lowering
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A 4H-SiC n-p-n floating-base phototransistor (FB-PT) achieving ultra-high responsivity via a punch-through induced barrier lowering (PT-IBL) mechanism is reported. By engineering the base region to operate near the structural punch-through state, the emitter-base barrier becomes highly sensitive to photogenerated hole accumulation. The device exhibits an ultra-high peak responsivity of 9.8 × 104 A/W at 272 nm under 9 V bias. Based on the high spatial response uniformity observed at 7 V, the FB-PT demonstrates an optimized balance of performance, yielding a specific detectivity (D*) of ~3.5 × 1013 Jones, a noise equivalent power (NEP) of ~10.8 fW, a responsivity of 125 A/W, and rise/fall times of ~5.1/9.4 ms. Furthermore, a single-pixel imaging system using this FB-PT reconstructs high-fidelity patterns under a low light intensity of ~1 μW/cm2. These results quantify the potential of the PT-IBL mechanism for sensitive UV sensing and integrated optoelectronics.
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