1. A metal/n-GaAs Schottky Barrier is formed by depositing platinum on n-GaAs. The electron affinity of GaAs is 4.0 eV. The work function of Pt is 5.0 eV. The doping in
GaAs is 1E16/cm3, and Nc=5E17/cm3.
i) Draw the thermal equilibrium energy band diagram for the structure
ii) Calculate the barrier height and the built-in voltage
iii) Calculate the depletion width in GaAs, given ε(total) for GaAs=1E-12 F/cm --> w=sqrt((2*ε*Vbi)/(q*ND))
iv) Calculate the depletion capacitance for 1 cm2 area
v) Draw the energy band diagrams under forward bias and reverse bias
3. Now we change the doping of GaAs from n to p. The doping level is again 1E16/cm3. Nv=1.5E19/cm3. I now deposit Al on GaAs instead of Pt. The work function of Al is 4.2 eV. Rework problem (i)-(iv) of problem 1 for these conditions for p-type Schottky barrier device
1. A metal/n-GaAs Schottky Barrier is formed by depositing platinum on n-GaAs. The electron affinity of...
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