Suppose a silicon crystal is p-type doped with a concentration of n_a = l0¹⁶ cm^–3 of boron atoms. If the crystal slab is heated in an atmosphere containing phosphorus atoms, the latter will diffuse as donors with a concentration n_d (x) into the semiconductor. They will form a p-u junction at that depth at which n_a = n_d. Assume that the diffusion conditions are such that the phosphorus concentration at the surface is maintained at n_d (0) = l0¹⁷ cm^–3. Take the diffusion coefficient of donors to be D = 10^–13 cm² s^-1.What is the value of the constant C in the equation x = Ct^2/2, where x is the depth of the p-n junction and t is the time?