boron atoms in an area concentration of 10^16 are introduced into an n-type wafer from a boron source in a carrier gas. the strating n-type wafer has a uniform donor contration of 5*10^15 cm. The subsequent drive-in diffusion is carried out at 1100 C in a oxygen ambient. The desired junction depth is micron. How long should the drive-in diffusion be continued? Assume that the diffusion coefficient of boron is 10^-12 cm at 1100 C
Iteratively solving for the time t (seconds) (by trial and error) gives