Hi,

I am working on the growth and characterization of III-Nitride thin films and nanostructures. our concentration is to grow high quality pure and rare earth (Er, Yb, Eu) doped GaN and InGaN nanostructures directly on the substrate without any buffer layer. We are getting very low mobility (less than 100 cm^2/V. s.) and higher carrier concentration (more than 10^19 cm-3) and we got the same (nearly) by using different instruments and different places. We are using Van-der Pauw method. So, i think its genuine. so, i am trying to understand what is the reason for this? Can anyone educate me on this, please.

thanks in advance.