|visits||member for||2 years, 6 months|
|seen||Dec 18 at 16:16|
Confused about charge seperation in solar cells
I've been doing a bit of reading and it's my understanding that there are two competing forces for driving electrons and holes across a p-n junction, diffusion and drift. Diffusion makes electrons travel from the n-type to the p-type material, leaving behind positive ions. A depletion region occurs, and over this region there is an electric field due to the electrons in the p-type and positive ions in the n-type. This electric field balances out the diffusion so there's no net current. So how is it then when a electron hole pair is created, it creates current?