Figure 3

XPS results comparing various LN surface treatments (a)–(d) The O1s peak of CLN, annealed LN, annealed and BOE cleaned LN, and piranha submerged LN. Each peak is compensated from charging by shifting the measured Nb peak to LN Nb3d5/2 peak value of 207.3 eV; the background counts have also been subtracted from each peak. Fits to three Gaussian-Lorentzian bands for three kinds of oxygen bonding are plotted in grey: metal oxide centered at 530 eV in light grey, organic C=O bonding at 531.5 eV in medium grey, and organic C–O bonding at 533 eV in dark grey. Peaks with less of a carbon presence have negligible organic carbon peak bands, such as the case with piranha (d). (e)–(h) The four primary elemental peaks (O1s, C1s, Nb3d, and Li1s) of LN before (blue) and after (red) ion sputtering the surface with a Gas Cluster Ion Beam. Note that the smaller, narrower Li1s peak at 54.8eV overlaps with Nb4s, which resides at 60.2eV. Removal of surface lying organics can be seen with the near annihilation of the C1s peak, as well as narrowing of the O1s peak. (i)–(k) The relative atomic percentage ratios of each measured surface treated sample are calculated by integrating the counts in each peak. Percentages are averaged across several positions of multiple 10mm samples of each surface preparation type. Black lines represent the error bars calculated from the standard deviation between measurements of the same surface treatment.