Double Layer or Depletion Region?

[hobbs125]

Hello everyone,

Recently I have been studying double layers. As I have studied I have realized that there seem to be a lot of similarities between a double layer and a depletion region in a PN junction.

The each form electric fields (and thus have a capacitance) and they each limit (or stop) the flow of charge carriers.

So my question is: Are they the same thing? In what ways are they different?

 

[analogdesign]

Double layer of what?

 

[hobbs125]

A semiconductor and water.

 

[analogdesign]

I would say no they aren't the same. For one, a depletion region still generates carrier through thermal and generation-combination processes (e.g. optical). These carriers are swept away but they wouldn't be created in water.

Also, a depletion region is a rectifying region because its asymmetric. The water layer wouldn't rectify.