Abstract: An electronic package is provided that includes a flexible polyimide film carrier having electronic circuitry on both of its major surfaces and a plurality of solder interconnection pads on a first major surface; solder mask layers located on both major surfaces, provided that areas between subsequently to be applied individual circuit chips on the first major surface exist that are free from the solder mask; and a plurality of modules attached to the film carrier by the solder balls or bumps. Also provided is a method for fabricating the electronic package that includes reflow of the solder balls or bumps to achieve attachment of the modules.

Abstract: The technique involves attaching a stiffener to a flexible substrate that has solder balls on the substrate. The steps include locating the flexible substrate on the stiffener with the solder balls on the side away from the stiffener, and drawing a vacuum to hold the flexible substrate in place. Locating the stiffener on a support with a pressure sensitive adhesive on a surface facing away from the support, and drawing a vacuum to hold the stiffener in place. Then, applying a pressure around the solder balls against the flexible substrate in the order of 2000 pounds per square inch to force the flexible substrate against the stiffener.

Abstract: The technique involves attaching a stiffener to a flexible substrate that has solder balls on the substrate. The steps include locating the flexible substrate on the stiffener with the solder balls on the side away from the stiffener, and drawing a vacuum to hold the flexible substrate in place. Locating the stiffener on a support with a pressure sensitive adhesive on a surface facing away from the support, and drawing a vacuum to hold the stiffener in place. Then, applying a pressure around the solder balls against the flexible substrate in the order of 2000 pounds per square inch to force the flexible substrate against the stiffener.

Abstract: An electronic package is provided that includes a flexible polyimide film carrier having electronic circuitry on both of its major surfaces and a plurality of solder interconnection pads on a first major surface; solder mask layers located on both major surfaces, provided that areas between subsequently to be applied individual circuit chips on the first major surface exist that are free from the solder mask; and a plurality of modules attached to the film carrier by the solder balls or bumps. Also provided is a method for fabricating the electronic package that includes reflow of the solder balls or bumps to achieve attachment of the modules.