Electrical leakage in low-k/Cu interconnect structures is becoming a growing vital concern as the nano-electronics industry moves to increasingly tighter metal spacing’s for sub 22 nm technology nodes and continues to replace dense SiO2 dielectrics with low density / porous SiOC:H “low-k” dielectric materials. In order to understand the various possible leakage mechanisms in low-k/Cu interconnects, a knowledge of the basic band alignment between Cu and low-k dielectric materials is needed but has gone largely unreported. In this regard, we have utilized X-ray Photoelectron Spectroscopy (XPS) to measure the Valence Band Alignment and Schottky Barrier at interfaces of importance to Cu/low-k interconnects. XPS has been used extensively for determining the band alignment of numerous semiconductors to other semiconductors, metals, and dielectrics. In this paper, we demonstrate that XPS can also be utilized to determine the band alignment at interfaces between amorphous dielectrics and metals of interest to the low-k/Cu interconnects industry. Specifically, we have utilized XPS to determine the Schottky Barrier between Cu and low-k dielectric SiC and SiCN capping layers deposited on Cu via Plasma Enhanced Chemical Vapor Deposition (PECVD). We have also utilized XPS to determine the valence band alignment at SiCN:H/SiOC:H interfaces. Lastly, the impact of various plasma surface treatments on the band alignment at these interfaces was also investigated.