Potentially, multi-layered organic sensors can over-perform BSI by a big margin. Their biggest advantage is that the dye absorption could be tuned to have very high QE in each of three colors, crosstalk can be minimized and each pixel location can detect and process all three color signals. Bayer sensors, on the other hand, get only one color per pixel, effectively discarding 2/3 of the incoming signal.
Said all this there are few challenges that organic sensors should overcome on their way to the mass market:
- Process reproducibility and reliability. So far thin film organic photodiodes experience large variation, in comparison with silicon photodiodes.
- Large dark current, orders of magnitude higher than Si photodiodes of the same size
- Noise, primarily kTC noise. It appears that generic 4T pixel architecture used for kTC noise suppression is not applicable for organic sensors. Other techniques for the noise reduction should be developed for them.
