Patent ID: 7309961

Claim:
An apparatus for accelerating a plasma, comprising: a chamber configured with an end wall and with at least one side wall that is substantially parallel to an axial direction of said chamber; a first coil disposed adjacent said end wall that operates at a first frequency to generate said plasma in a gas located within said chamber; a plurality of second coils disposed around said chamber adjacent said side wall and spaced from one another along said axial direction, said second coils being operated at a second frequency and out of phase with one another to accelerate said plasma along said axial direction, where the number of second coils is dependent upon the second frequency; a plurality of third coils disposed around said chamber adjacent said second side wall and spaced from one another along said axial direction, wherein the plurality of third coils is in a lower portion on one end of the chamber adjacent to a nozzle portion; and separate signal connections between a signal generation unit and each of the first, second and third coils, respectively.