Contamination control and ultrasensitive chemical analysis

Requirements for low contamination processing in future device fabrication demand that the cleanliness of equipment and media be qualified and monitored. Advanced analytical methods for elemental identification and mapping of impurity patterns allow one to analyze contamination directly at levels of 10 high9 cm high-2 on wafer surfaces, down to 10 high11 cm high-3 in bulk silicon via electrical measurements, and in the ppb to ppt range in liquid chemicals as well as gases. Today's advanced analytical techniques meet the requirements of present and near-future device fabrication, but requirements on the contamination level for device fabrication of the 64 MBit DRAM and beyond will demand new and more sensitive analytical support.