in 9.2, "Magnetically condition the target by rotating it counterclockwise on the target support table five complete turns", what is the purpose of "magnetically condition"? in the note it claims it is to achieve stable, repeatable PTF value. but why? Does not the original status (i.e. not magnetized) represent better the target material?
why need two methods, one circumferentially magnetize, the other radially? the horseshoe magnet pole face gap is only 1 inch, the magnetized area is very local with respective to the big target (normally >5'' dia)
why not use a straight magnet (vs horseshore) (so the flux directly goes through the thickness of target, better representative to the magnetic circle in magnetron sputtering system) and why not use a magnet with high coercivity (vs AlNico 5) and so not easy to be de-mag?
it seems to me there are quite a few things to improve with this standard method.