In regard semiconductor photodiodes the following statements are mode—
1. In a typical volt ampere characteristic for a given illumination, the reverse current is almost constant for increasing reverse voltage.
2. Due to creation of electron hole pairs by incident photons, the essential concentration of majority carriers is much greater than the percentage increase in minority carriers.
3. The radiation can be considered as a minority carrier injector.
4. The photo-current is due to drifting of injected carriers.
Of the four statements, the correct statements are—