Abstract: A dielectric for use in making high optical contrast and UV light fluorescing substrates usable in printed circuit boards, which in turn may form part of an electronic package. The dielectric comprises a resin, a coloring agent, and a fluorescing agent and does not include a reinforcing material. The substrate also includes a first conductive layer on the dielectric layer.

Abstract: A method of making a circuitized substrate such as a printed circuit board having at least one hole therein which comprises the steps of providing a layer of dielectric, forming at least one (and preferably several) holes therein, providing a fill member including a quantity of fill material and reinforcement means located within the fill material, positioning the fill member on the dielectric over the holes and thereafter applying a predetermined force sufficient to cause only the fill material to be forcibly driven into the accommodating hole(s), not the reinforcement means. Subsequent steps can include forming a layer of circuitry on the substrate's external surface and over the filled holes such that an electrical component such as a ball grid array (BGA), semiconductor chip, etc. may be directly positioned on and/or over the hole(s). A fill member usable with the method is also provided.

Abstract: A method of making a circuitized substrate such as a printed circuit board having at least one hole therein which comprises the steps of providing a layer of dielectric, forming at least one (and preferably several) holes therein, positioning a thin layer of support material atop the dielectric layer and over the hole(s), positioning a quantity of fill material on the thin layer of support material (preferably before positioning the thin layer on the dielectric) and thereafter applying a predetermined force sufficient to cause the thin support layer to rupture or otherwise deform (including melting from heat application thereto) such that the fill material is forcibly driven into the accommodating hole(s). Subsequent steps can include forming a layer of circuitry on the substrate's external surface and over the filled holes such that an electrical component such as a ball grid array (BGA), semiconductor chip, etc. may be directly positioned on and/or over the hole(s).

Abstract: A new method of preparing blind vias in printed circuit boards and other substrates allows for the drilling of holes for connection between conductive layers, in insulating layers prior to laminating insulating layers together. Each insulative layer is prepared with patterned conductive wiring and holes are drilled through the layer at points where wiring is to connect to another level of wiring. Two layers are aligned, using mechanical, optical, or other alignment mechanisms, and subsequently laminated together. The holes are plated with conductor after lamination to form an electrical connection. Additional layers can be added by the same method.