Q.3 A GaN LED consists of a 1.5 um thick N-GaN layer of donor concentration No = 1x 1018 cm-3 and an Mg-doped 0.25 um th
Posted: Tue Apr 12, 2022 10:14 am
Q.3 A GaN LED consists of a 1.5 um thick N-GaN layer of donor concentration No = 1x 1018 cm-3 and an Mg-doped 0.25 um thick P-GaN layer with acceptor concentration Na = 2 x 10 cm (a) Find the built-in potential of the homojunction at 300 K if the intrinsic carrier concentration is ni = Nc Ny exp{-E/(2kgT)} where Nc, Ny are the densities of states in the conduction and valence bands, respectively, Nc 24.3 x 1014 * 11.5cm-3) Ny = 8.9 x 1015 * 11.5cm-3) * And the energy gap versus temperature relationship is 7.7 x 10-412 Ec(T) = E(0) -- T + 600 where Ec0) = 3.47 eV (wurtzite). (6 marks) (b) Calculate the percentage of the total diode thickness depleted under zero bias if the dielectric constant of GaN is 8.9. (6 marks)