MULTIPLE ANODE PLASMA FOR CVD IN A HOLLOW ARTICLE

摘要

A method and apparatus for plasma enhanced chemical vapor deposition to an interior region of a hollow, tubular, high aspect ratio workpiece are disclosed. A plurality of anodes are disposed in axially spaced apart arrangement, to the interior of the workpiece. A process gas is introduced into the region. A respective individualized DC or pulsed DC bias is applied to each of the anodes. The bias excites the process gas into a plasma. The workpiece is biased in a hollow cathode arrangement. Pressure is controlled in the interior region to maintain the plasma. An elongated support tube arranges the anodes, and receives a process gas tube. A current splitter provides a respective selected proportion of a total current to each anode. One or more notch diffusers or chamber diffusers may diffuse the process gas or a plasma moderating gas. Plasma impedance and distribution may be controlled using various means.

主权项

1. An apparatus for chemical vapor deposition to an elongated interior region of a hollow tubular workpiece, comprising:
a plurality of anodes in axial spaced apart arrangement, dimensioned to be distributed along an elongated interior region of a hollow conductive workpiece; an electrical biasing circuit connected to provide an individualized DC or pulsed DC bias to each of the plurality of anodes; and a gas supply conduit connectable to deliver a process gas to the interior region of the workpiece at a pressure of the interior region of the workpiece controlled to achieve a plasma.