Method of making ball grid array package

Abstract

A method of making a ball grid array package comprises the steps of: (a) providing a film having an opening defined therein; (b) placing the film on a substrate; (c) attaching a semiconductor chip onto the substrate such that the semiconductor chip is positioned in the opening of the film; (d) electrically coupling the semiconductor chip to the substrate; (e) providing a molding die having a runner, a gate and a molding cavity defined therein, wherein the runner is connected to the molding cavity through the gate; (f) closing and clamping the molding die in a manner that the semiconductor chip is positioned in the molding cavity wherein the edges of the molding cavity fit entirely within the opening of the film and the edges of the runners and the gates are entirely positioned against the film; (g) transferring a hardenable molding compound into the molding cavity; (h) hardening the molding compound; (i) unclamping and opening the molding die; and (j) simultaneously removing the film and degating. The film in accordance with the present invention is characterized in that the adhesive force between the film and the molding compound is greater than the adhesive force between the film and the substrate. This makes the film tend to adhere to the excess molding compound; hence, the film will be removed along with the excess molding compound during the step (j) thereby automating the molding process.