Where M1 is the ion mass and M2 is the substrate mass.
A wide variety of masking materials can be used during the implantation and the thickness of the mask can be estimated using the above equations once the range (or stopping) parameters of the mask material is known. The important goals of damage annealing are:
Remove primary damage created by the implant and activate the dopants.
Restore silicon lattice to its perfect crystalline state.
Restore the electron and hole mobility.
Do this without appreciable dopant redistribution.