... Elements Analytical methods applied Product specificationsParameter Elements Analytical methods appliedPackagingDonors (P, As, Sb) ≤ 5.0ppbaAcceptors (B, Al) ≤ 0.1ppbaphoto-luminescence ... iii) Quantity and weightFe ≤ 10.0ppbw mass spectrometry (ICP-iv) Poly grade; photovoltaic silicon Ni ≤ 2.0ppbw MS) or equivalent method ... solar ingot,solar cells,solar panels,solar inverter,6N,9N poly silicon,