What you will do? if I say
"Depth is a function of sputtering time"
We often say "time scaling" or "reduced counts to silicon".
Depth is a function of sputtering time?
Is it true?
The answer is NO!
Time and space are linearly independent each other.
Then the depth and the sputtering time are also independent each other.
Why not can we estimate the depth directly?
Why we need to calibrate?
The depth without time function
Only solution for absolute scale depth
is the shave-off depth profiling.
OK! Go on.