A semiconductor p-n junction has charge density p(x) and permittivity (x), -Pp x...

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A semiconductor p-n junction has charge density p(x) and permittivity (x), -Pp² x <x<0 [P₂₂ 0<x<x₁ p(x) = ε(x) = Ep, x<0 En, x>0 (&> &) The boundary conditions are given by i) &(-x) = 0 and &(x)=0 for the electric field ii) V(-x) = 0 To find the potential and electric field, we use the Poisson's equation, d dV (x) dx dx -[(x)&(x)]=p(x) with &(x)=- [*(x)&(x)] = (a) Describe the depletion approximation in the p-n junction and its validity condition (b) What is the boundary condition for &(x) at x=0? (c) Derive the electric field &(x). (d) Derive the potential V(x). (e) Schematically Draw electric field &(x) and potential V(x) A semiconductor p-n junction has charge density p(x) and permittivity (x), -Pp² x <x<0 [P₂₂ 0<x<x₁ p(x) = ε(x) = Ep, x<0 En, x>0 (&> &) The boundary conditions are given by i) &(-x) = 0 and &(x)=0 for the electric field ii) V(-x) = 0 To find the potential and electric field, we use the Poisson's equation, d dV (x) dx dx -[(x)&(x)]=p(x) with &(x)=- [*(x)&(x)] = (a) Describe the depletion approximation in the p-n junction and its validity condition (b) What is the boundary condition for &(x) at x=0? (c) Derive the electric field &(x). (d) Derive the potential V(x). (e) Schematically Draw electric field &(x) and potential V(x)

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a The depletion approximation assumes that the charge density x is zero within the dep... View the full answer