| 摘要 |
A method of plasma etching blind vias in printed wiring board dielectric which comprises the steps of providing a printed wiring board of organic material having a buried electrically conductive pattern in the organic material and an electrically conductive layer on the surface of the board, removing predetermined portions of the electrically conductive layer to expose the organic material thereunder and define at least one via location thereat, providing a plasma etching chamber having one or more pairs of spaced parallel electrodes, positioning the board between the said electrodes, electrically connecting the board to one of said electrodes and having the surface facing and parellel to the electrodes, filling the chamber with a mixture of an oxidizing gas and a fluorocarbon gas, etching the organic material from the exposed organic material at the surface to the buried pattern to expose the buried pattern by applying an RF signal across the electrodes, and forming an electrically conductive layer of the exposed surfaces of the organic material contacting the exposed buried pattern and the conductive layer.
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