# 2. (20 p) The figure below shows the electron and hole concentration in a silicon region. The electron and hole mobility is 500 and 250 cm²/V*s respectively. a) If the drift current density of holes at x-2 μm is 500A/cm² left to right, finds the electric field in the silicon region. b) Show the direction of hole and electron drift and the direction of their drift current (at the right to th figure) c) Show the direction of hole and electron diffusion and the direction of their diffusion currents (at t right to the figure) d) Calculate the total drift current density at x=2 μm e) Calculate the diffusion current density at x=2 μm f) Compare the drift and diffusion current density at x=2 with the current values at x=0 (without calculations). Are they the same or different? Explain why. 1.01 x 1018 1016 x = 0 p(x) 1018 n(x) b 10+ x = 2 μm