Abstract: A sintering film comprising one or more metals, one or more metal alloys, or blends of one or more metals and one or more metal alloys, is prepared optionally using a solid or semi-solid organic binder. The organic binder can have fluxing functionality; the organic binder can be one that will partially or completely decompose upon sintering of the metal or metal alloy in the composition. In one embodiment, the sintering film is provided on an end use substrate, such as a silicon die or wafer, or a metal circuit board or foil, or the sintering film is provided on a carrier, such as a metal mesh. Preparation is accomplished by dispersing the metal or metal alloy in a suitable solvent, with or without a binder, and exposing the composition to high temperature to evaporate off the solvent and partially sinter the metal or metal alloy.

Abstract: A process is described that enables the active side of a bumped wafer to be coated with a front side protection (FSP) material or wafer level underfill (WLUF) without contaminating the solder bumps with the coating material and/or filler. In this process a repellent material is applied to a top portion of the solder bumps on the active side of the wafer, the front side of the wafer is then coated with the coating material, the coating material is hardened, and optionally the repellent material is removed from the solder bumps.