Patent ID: 8282850

Claim:
A method comprising: providing a plasma control structure defining a first portion of a plasma flow passage and a second portion of the plasma flow passage, wherein the first and second portions are linearly aligned with one another, the plasma control structure including spaced first and second electrodes associated with the first portion of the plasma flow passage, the first portion of the plasma flow passage extending between and being immediately adjacent each of the first and second electrodes; passing plasma through the first portion of the plasma flow passage, wherein the plasma has first particles and second particles; and imposing on the plasma passing through the first portion of the plasma flow passage a deflective force that influences the first particles but not the second particles so that a ratio of first particles to second particles in plasma flowing through the second portion of the plasma flow passage is different from that which flowed through the first portion of the plasma flow passage, wherein plasma flows successively through the first portion of the plasma flow passage and the second portion of the plasma flow passage, the imposing a deflective force including applying a voltage between the first and second electrodes, wherein the plasma control structure includes a first stencil filter with a first hole therethrough defining the first portion of the plasma flow passage and includes a second stencil filter with a second hole therethrough defining the second portion of the plasma flow passage, the first and second electrodes being placed at the first hole and separated from each other in a direction transverse to a direction of plasma flow.