RF reference cell for plasma etching studies

Summary form only given. The reference cell was designed with three objectives: (1) the cell should be easily duplicated so that the design can be portable among laboratories: (2) the cell should be fabricated with as many standard components as possible to keep costs down; and (3) the cell should accommodate a variety of diagnostic techniques, including. but not limited to, optical emission, laser spectroscopy, mass spectroscopy, and probes. The reference cell consists of a stainless-steel vacuum chamber with 4-in.-diameter water-cooled parallel-plate electrodes. Gas is injected into the discharge through a showerhead in the upper electrode and is pumped out through a symmetrical pumping configuration. Two 8-in. ports. two 6-in. ports. and four 2.75-in. ports are provided for various diagnostic measurements, including mass spectrometer sampling through the lower electrode. Flexibility is achieved by allowing the electrodes to be independently powered, grounded, floating, or biased