Deposition rate regulation by computer control of sputtering systems
Patent 4166783 Issued on September 4, 1979. Estimated Expiration Date: April 17, 1998. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A sputtering system utilizes a computer to monitor the power dissipation in the sputtering source and to accumulate the history of usage of the particular sputtering target. Desired deposition rate information is input to the computer, which establishes and maintains the desired rate and controls the plasma discharge to compensate for aging and deterioration of the target. End of useful target life is determined by the computer from objective criteria to trigger appropriate actions.