Direct & Indirect band gap Semiconductors

[ashishbatra]

direct & indirect bandgap semiconductors

Plz give me a brief description about Direct & Indirect band gap Semiconductors
or any good link

 

[elmolla]

If we plot the E-k Diagram of any material, we will get the Valency and Conduction band shapes for every k (K is the wave number which is directly proportional to momentum and E is the total Energy).

If we define the energy band gap as the distance between the maximum point of the Valency band(VB) and the minimum point of the Conduction band(CB), we have one of two cases:

1. The max of the VB is directly under the min of the CB: This is called a direct badn gap material.

2. The max of the VB is not directly under the min of the CB: This is called an indirect band gap material.

 

[electronics_kumar]

single element semiconductor is having direct bandgap whereas compound ( combination of two elements)semiconductor is having indirect band gap....

 

[japholix]

single element semiconductor is having direct bandgap whereas compound ( combination of two elements)semiconductor is having indirect band gap....

Not really : Si has an indirect bandgap while GaAs has a direct one

 

[ashubrads]

single element semiconductor is having direct bandgap whereas compound ( combination of two elements)semiconductor is having indirect band gap....

"basically there's no such true link or idea that a single element semiconductor is direct and compound semiconductor is indirect."
For example : Silicon is an indirect band gap semiconductor while GaAs is a direct. So please make the proper corrections.

Also,Please let me know if I'm wrong.. !!