Book excerpt: The issues addressed by the Sixth International Symposium on the Ultra Clean Processing of Silicon Surfaces included all aspects of ultra-clean Si-technology, cleaning and contamination control in both front-end-of-line (FEOL) and back-end-of-line (BEOL) processing. Volume is indexed by Thomson Reuters CPCI-S (WoS). This covered studies of Si-surface chemistry and topography and its relationship to device performance and process yield, cleaning in relationship to new gate stacks, cleaning at the interconnect level, resist stripping and polymer removal, cleaning and contamination control of various new materials, wafer backside cleaning and cleaning following Chemical-Mechanical-Polishing (CMP).