The surface concentration is fixed at N0=1.8e20/cm^2 when diffusing boron into a uniformly doped n-type substrate. The atomic diffusion constant for boron in Si at the temperature of 950 C is 3.0e-15 cm^2/s. calculate the metallurgical junction depths for the following conditions A)Nd=1.0e15 /cm^3 for 30 min B)Diffused at 950 C for 1 hr 30 min with Nd=1.5e16.