Plasma-based nitrogen implantation of chrome-plated steel

Plasma-based ion implantation (PBII) of nitrogen into chrome plated-steel i s discussed with regard to dimensional homogeneity, depth distribution and the possibility of combining different implantation modes. A stainless hold er with 60 X 10 mm(2) trenches at depths of 60, 40, 20 and 10 mm was made. The chromium-plated steel plates were fixed on the bottom of the trenches a nd treated by PBII under various conditions. The depth profiles and chemica l bonds were measured with X-ray photoelectron spectroscopy (XPS) combined with Ar sputtering. The primary results confirmed that nitrogen PBII could introduce a significant amount of nitrogen into the chrome-plated layers in a shorter time than a conventional beam-line implanter. The implanted nitr ogen was observed to combine with chromium. The depth profiles of nitrogen were the same for samples set on holder surfaces both facing and reversed t o the RF source, which suggested homogeneous implantation in all directions . The PBII treatment was found to be homogenous for the trenches with an as pect ratio less than 4 without sample manipulation. A rapid elevation in te mperature occurred during PBII treatment. Control of the target temperature remains as a future challenge. (C) 2001 Elsevier Science B.V. All rights r eserved.