Abstract: Mold pieces (105 and 110) for molding a layer of mold compound on the interconnect side of a bumped semiconductor wafer (118) include a primary cavity (117) and secondary cavities (120) into which excess mold compound from the primary cavity (117) flows. The secondary cavities (120) include a plunger (130) that asserts a predetermined backpressure that is equal to a desired mold compound pressure on the mold compound during molding. As most of the excess mold compound in the primary cavity (117) is forced to flow into the secondary cavities (120), this advantageously leaves a relatively thin layer of mold compound on the semiconductor wafer (118), which can then be removed, for example by grinding, in a relatively short time. Mold piece (105) further comprises a movable cavity bar (115) that can be moved away from mold piece (105) after molding and be cooled to detach the molded substrate that adheres to the cavity bar.

Abstract: Mold pieces (105 and 110) for molding a layer of mold compound on the interconnect side of a bumped semiconductor wafer (118) include a primary cavity (117) and secondary cavities (120) into which excess mold compound from the primary cavity (117) flows. The secondary cavities (120) include a plunger (130) that asserts a predetermined backpressure that is equal to a desired mold compound pressure on the mold compound during molding. As most of the excess mold compound in the primary cavity (117) is forced to flow into the secondary cavities (120), this advantageously leaves a relatively thin layer of mold compound on the semiconductor wafer (118), which can then be removed, for example by grinding, in a relatively short time. Mold piece (105) further comprises a movable cavity bar (115) that can be moved away from mold piece (105) after molding and be cooled to detach the molded substrate that adheres to the cavity bar.

Abstract: Mold pieces (105 and 110) for molding a layer of mold compound on the interconnect side of a bumped semiconductor wafer (118) include a primary cavity (117) and secondary cavities (120) into which excess mold compound from the primary cavity (117) flows. The secondary cavities (120) include a plunger (130) that asserts a predetermined backpressure that is equal to a desired mold compound pressure on the mold compound during molding. As most of the excess mold compound in the primary cavity (117) is forced to flow into the secondary cavities (120), this advantageously leaves a relatively thin layer of mold compound on the semiconductor wafer (118), which can then be removed, for example by grinding in a relatively short time. Mold piece (105) further comprises a movable cavity bar (115) that can be moved away from mold piece (105) after molding and be cooled to detach the molded substrate that adheres to the cavity bar.

Abstract: Specifications of a flip chip package and mold compound for a package are provided to a mold flow simulator and locations of void formation in the package during molding, identified. Subsequently, a substrate (124) for the package is designed with vias (206) at the locations of void formation. During molding, air pockets at the locations of void formation escape through the vias (206) and vents (116) in the lower cavity bar (110), as mold compound flows between the die and the substrate (124) and forces the air out. In addition, the lower cavity bar (110) has a down set central location (114), which allows air to pass from the vias (206) to the vents (116). In addition, as the diameter of a via (206) is between 20-30 microns, more area on the lower surface of the substrate (124) is available for terminals arranged in an array.

Abstract: Mold pieces (105 and 110) for molding a layer of mold compound on the interconnect side of a bumped semiconductor wafer (118) include a primary cavity (117) and secondary cavities (120) into which excess mold compound from the primary cavity (117) flows. The secondary cavities (120) include a plunger (130) that asserts a predetermined backpressure that is equal to a desired mold compound pressure on the mold compound during molding. As most of the excess mold compound in the primary cavity (117) is forced to flow into the secondary cavities (120), this advantageously leaves a relatively thin layer of mold compound on the semiconductor wafer (118), which can then be removed, for example by grinding in a relatively short time. Mould piece (105) further comprises a movable cavity bar (115) that can be moved away from mould piece (105) after molding and be cooled to detach the molded substrate that adheres to the cavity bar.