Anonymous @ on
Adept values and hand calculations do not match
In the n AlGaAs-pGaAs heterojunction example, the potential values do not seem to match with my hand calculations. If I use the formula for Vbi and then use that to calculate the VJn and VJp (potential drops on the n AlGaAs side and p GaAs side respectively), I get the following values 0.713 V and 0.660 V.
In Adept (at equilibrium, Va=0 V ), the potential value at x=0 um (on the AlGaAs side) is 0.55 V and at x = 1um is -0.81 V. The value at x =0.5 um is -0.15 V. Using these values one can get the potential drops for the n and the p sides as in the hand calculation above.
My question is , how did we get this value at x= 0.5 um for the voltage in the first place. I think that this has to do with choosing a reference material for this system (like in Dr Lundstrom’s heterojunction lectures). But, if I choose GaAs as the reference material I am unable to get the same values as ADEPT calculates for the potential. I am using the following expression (Eqn 44 in Dr Lundstrom’s heterostructure fundamentals notes) for the potential on the p GaAs side.
I am not sure how to go about reproducing the ADEPT solution with some hand calculations to convince myself.
Thanks for your help on this..