$kT=0\mathrm{.}026eV$ at $300K,Si{n}_i={10}^{10}c{m}^{-3}$ at $300K,Si{E}_g=1\mathrm{.}1eV,q=1\mathrm{.}6{10}^{-19}C,h=6\mathrm{.}63{10}^{-34}J-s,{}_0=8\mathrm{.}85{10}^{-14}$

$\frac{F}{c}m,$ Relative permittivity of $Si=11\mathrm{.}8,c=3{10}^{10}c\frac{m}{s},I_0=qA(D_p\frac{p_p}{L_p}+D_n\frac{n_p}{L_n})$

$4.(10$ p $)$ Sketch the energy band diagram of an abrupt

SemiA$-$SemiB hetero junction $($SemiA: N ${?}^{+},E_g=2$

eV $,$ SemiB: P$,($:$E_g=1\mathrm{.}1eV$