Surface elemental quantification of Au-Pd pre-plated leadframe by means of X-ray Photoelectron Spectroscopy

Quantification of sample with Palladium (Pd) and Gold (Au) using X-ray Photoelectron Spectroscopy (XPS) could be a great challenge due to the overlapping of Pd, Au and Oxygen photoelectron lines. Conventional baseline subtraction method is not applicable when the content of Pd is too low. A metrology for Pd-Au pre-plated leadframe surface atomic percent quantification using XPS deconvolution method was demonstrated to be able to quantify Pd-Au pre-plated leadframe with low Pd content. Three XPS wide scans were performed on the same analysis spot at energy resolutions of 1 eV/step, 0.5 eV/step and 0.1 eV/step respectively. The same metrology was utilized for atomic percent quantification and compare the accuracy based on deconvolution results.