The current in the forward bias (mA)



The current in the forward bias (mA) is known to be more than the current in the reverse bias (µA). What is the reason, to operate the photodiode in reverse bias?


When photodiode is illuminated with light due to breaking of covalent bonds, equal number of additional electrons and holes comes into existence whereas fractional change in minority charge carrier is much higher than fractional change in majority charge carrier. Since, the fractional change of minority carrier current is measurable significantly in reverse bias than that of forward bias. Therefore, photodiode is connected in reverse bias.