ALEXANDRIA, Va., May 5 -- United States Patent no. 12,620,554, issued on May 5, was assigned to Tokyo Electron Ltd. (Tokyo).
"Plasma processing with phase-locked waveforms" was invented by Pingshan Luan (Albany, N.Y.) and Minjoon Park (Albany, N.Y.).
According to the abstract* released by the U.S. Patent & Trademark Office: "A plasma processing method includes applying AC waveforms to a bottom electrode in a plasma chamber to generate a plasma. The method further includes applying a first pulse train including a first plurality of DC pulses to a top electrode in the plasma chamber, where each DC pulse of the first plurality of DC pulses includes a first on-state and a first off-state. And the method further includes applying a second puls...