摘要 |
A manufacturing process for a mutlilayer thermoplastic printed circuit substrate (200) begins with a thermoplastic core substrate (202) having a printed circuit pattern (204) on a surface (202A) of the core substrate. Either fully reacted or partially reacted thermoplastic material is dissolved in a suitable dissolving agent and then applied in the liquid state over the surface (202A) of the core substrate. Application is by spraying, dipping, spinning or rolling. This results in a layer of liquid thermoplastic material covering the printed circuit pattern on the core substrate. The dissolving agent is then removed from the thermoplastic layer, leaving behind a uniform, dry hard, dielectric film of thermoplastic resin (206). Using photolithographic techniques, a via (206A) is opened up in the dielectric layer. If the starting material for the dielectric layer was partially reacted thermoplastic resin, the dielectric layer is now fully cured. A second printed circuit pattern (208) is then applied over the dielectric layer and into the via, thereby forming a conductive through-hole, which connects the two printed circuit patterns.
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