Question 1: (25 points) Consider a n-type silicon wafer with…
Question 1: (25 points) Consider a n-type silicon wafer with a donor concentration of Nd = 1×1015 atoms/cm3 and Na = 0. Take the bandgap of silicon as 1.12 eV, NC = 2.80×1019 cm–3, NV = 1.04×1019 cm–3. To simplify the calculation, you can assume that these three values are all temperature independent. For the same reason, let’s assume that the electrons and holes obey the Boltzmann distribution. The Boltzmann constant is 1.38×10–23 J/K or 8.62×10–5 eV/K, and 1 eV = 1.60×10–19 J. Determine the temperature at which the intrinsic carrier concentrations is equal to the extrinsic electron concentration. (10 points) Determine the Fermi energy EF in EC – EF at 300 K for the n-type silicon assuming complete ionization of the donors. (5 points) Calculate the electron and hole concentrations at 700 K. You need the result from part (a) to determine which equations to use for this temperature. (10 points)