Patent ID: 7572398

Claim:
A method of manufacturing a semiconductor device comprising the steps of: (a) providing a mold having a first mold and a second mold opposing to the first mold, the first and second molds each having concaved portions, the concaved portions each defining a cavity for molding a semiconductor chip, the first mold having a plurality of cull portions, the second mold having a plurality of runner portions and a plurality of pot portions; (b) providing a cleaning sheet for the mold having a through hole, wherein the cleaning sheet is comprised of material such that the cleaning sheet can be impregnated with a portion of a cleaning resin; (c) setting the cleaning sheet on the mold such that the cleaning sheet is disposed between the first and second molds, such that the plurality of cull portions, the plurality of runner portions and the plurality of pot portions are overlapped with the cleaning sheet, and such that the through hole of the cleaning sheet is positioned at the concaved portions of the first and second molds in a plan view; (d) clamping the cleaning sheet by the first and second molds; (e) injecting the cleaning resin for the mold in the cavities such that the portion of the cleaning resin is bonded to a portion of the cleaning sheet; (f) after the step (e), removing the cleaning sheet and the cleaning resin from the mold; (g) after the step (f), disposing a lead frame with the semiconductor chip at the mold such that the semiconductor chip is positioned in the cavity; and (h) after the step (g), injecting an encapsulating resin in the cavity, to seal the semiconductor chip.