Does Ohmic Contact Affect the Energy Gap Shape of a P-N Junction?

[vincent.L]

led chips is a P-N jontion which MQW in middle. And than it bonds metal on P-side and N-side which we call ohmic contact.I had try to draw the band gap graph. Base on theory, when different material bond together, their fermi energy became the the same energy level. I know that the contact of silicon and metal bends the energy band gap because the fermi engery of metal force which of sillicon to be the same.
The question is, if that bending by ohmic contact making any affect of the energy gap shape of P-N jontion? (without considering MQW)
And, If metal on P-side and N-side is not the same(having different fermi level), when they all bond onto the sillicon, how is the band gap graph look like?(Is it seems like the fermi energy of sillicon force to equal these two metal fermi engergy?that will never happen!)

 

[BigJDubs]

The answer to your question is that, no, the ohmic contact does not affect the energy gap shape of the P-N junction without considering MQW. The reason for this is because the band gap of a P-N junction is determined by its intrinsic properties, and is not affected by the ohmic contacts. The metal contacts simply provide a mechanism for current to flow through the junction. However, if the metal on the P-side and N-side are not the same (i.e. have different Fermi levels), then the band gap graph will be slightly different than if they were the same. This is because the Fermi levels of the two metals will cause the Fermi level of the silicon to shift, which will in turn shift the band gap. However, this shift is usually quite small and does not have a large effect on the overall shape of the band gap.