Table 2 Dominant noise mechanisms of 2D photodetectors
From: How to characterize figures of merit of two-dimensional photodetectors
Noise mechanism | Thermal noise | Shot noise | g-r noise | 1/f noise |
|---|---|---|---|---|
\(\left\langle {i}_{{th}}^{2}\right\rangle=\frac{4{K}_{B}T}{{R}_{d}}\triangle f\) | \(\left\langle {i}_{{sh}}^{2}\right\rangle=2{qI}\triangle f\) | \(\left\langle {i}_{{gr}}^{2}\right\rangle=\frac{4{\overline{{\varDelta {N}^{2}}}}\tau }{1+{4\pi }^{2}{{f}^{2}\tau }^{2}}\) | \(\left\langle {i}_{1/f}^{2}\right\rangle=\frac{{{{\alpha }_{H}I}_{S}}^{2}}{{fN}}\triangle f\) | |
Noise characteristics | White noise characteristic dominated at high frequency | For 2D photodetectors of photoconductive gain with a prolonged carrier lifetime \(\tau\) from photogenerated carriers trapped by impurities and defects, g-r noise is proportional to photoconductive gain \(\langle {i}_{{gr}}^{2}\rangle=4qI_{ph}G\triangle f\) when \({4\pi }^{2}{{f}^{2}\tau }^{2}\ll 1\) | For 2D photodetectors with complex defect state, 1/f noise related to random fluctuation of carrier concentration and mobility should not be neglected | |
It should not be neglected in 2D photodetectors operating at room temperature | It has usually been considered as the only noise component by the early published work on 2D photodetectors | |||
