Apparatus for molding a semiconductor wafer and process therefor

摘要

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.

主权项

1. An apparatus comprising:
a press; a first mold piece coupled to the press, the first mold piece having a primary cavity for holding a substrate and a predetermined amount of mold compound on at least one surface of the substrate, the primary cavity configured for heating to melt the mold compound and form a layer of mold compound on the at least one surface of the substrate; a second mold piece coupled to the press, the second mold piece forming a secondary cavity coupled to the primary cavity, the secondary cavity configured to receiving excess mold compound from the primary cavity, and the secondary cavity having a third mold piece forming a movable portion for asserting a predetermined pressure on the mold compound while moving to receive the excess mold compound; and a fourth mold piece for separating a molded substrate from at least one of the mold pieces by removing the fourth mold piece with the molded substrate adhering thereto, and reducing a temperature of the fourth mold piece including abutting the fourth mold piece with a heat sink.