Atransistor is made by doping silicon (si) wafer with different phosphorus (p) dopants. it was given that si wafer contains no p to begin with. the diffusion coefficient of pin si is 6.5 x 10^-13 cm^2/s at temperature of 1100 c. assume the source provides a surface concentration of 10^20 atoms/cm^3 and diffusion time is one hour. compute the depth at which the concentration of p will be 10^18 atoms/cm^3 by using fick's second law.