| 摘要 |
A method for patterning a photoresist or insulating layer on a printed wiring board utilizes two photoreactive coatings comprising a photoprocessable ultraviolet (UV) sensitive layer overlaid with a thin, unexposed, undeveloped strip base silver film. A white light x-y plotter, preferably employing an octagonal aperture, is driven directly from a CAD system to expose the film on the board in the desired pattern without affecting the underlying UV sensitive layer. The film is then developed on the board and employed as an in situ mask for the underlying W layer during exposure of the board to a UV flood lamp. After UV exposure the film is peeled off to allow conventional processing of the selectively polymerized layer. This technique produces high resolution, inspectable onboard masks in full registration using reliable low energy plotters. |
