Sputtering with collinator cleaning within the sputtering chamber

Abstract

A method of sputtering material onto semiconductor wafers includes: a) providing a sputtering chamber with a sputtering target, a wafer supporting chuck having a supported first wafer, and a collimator positioned between the target and first wafer for filtering material sputtered from the target onto the first wafer; b) providing ionized sputtering atoms within the chamber; c) bombarding the target with the ionized sputtering atoms to dislodge target atoms; d) passing the dislodged target atoms through collimator openings and onto the first wafer, the dislodged target atoms coating the collimator and openings passing therethrough; e) removing the sputter deposited first wafer from the sputtering chamber without breaking vacuum; f) after removing the sputtered first wafer, cleaning the collimator within the chamber without breaking vacuum between removal of the first wafer and the cleaning of the collimator within the chamber; and g) after cleaning of the collimator within the chamber, providing a second wafer on the wafer supporting chuck within the chamber without breaking vacuum between the cleaning of the collimator and the providing of the second wafer in the chamber; and thereafter sputter depositing target atoms onto the second wafer. The cleaning comprises providing the collimator with a negative potential effective to attract bombarding ionized sputtering atoms to dislodgingly clean target atoms from the collimator. The cleaning is to a degree sufficient to render collimator service lifetime at least equal to that of the sputtering target. Other cleaning techniques are disclosed.