Patent ID: 7626126
Filing Date: 2009-12-01
Classification: H01L,H05K,Y02P

Abstract:
1. A multilayer semiconductor device, comprising: plural semiconductor devices, each comprising a circuit board for a ball grid array and a semiconductor chip provided on the circuit board, bonded through an adhesive on the circuit board, the plural semiconductor devices being bonded together by a reflow mounting process to use a solder ball for interlayer connection so as to form a multilayer structure, wherein the plural semiconductor devices each comprise projections for restricting inclination of the circuit board, wherein the projections are provided between two neighboring circuit boards, bonded through the adhesive on the circuit board, said projections being provided at a carry-in side area, relative to a reflow furnace in which the plural semiconductor devices are carried and bonded together to form the multilayer structure, and at an opposite carry-in side area that is opposite to the carry-in side area, wherein the carry-in side area and the opposite carry-in side area are located at edges on an upper surface of a lower one of the two neighboring circuit boards, the semiconductor chip and the solder ball being mounted on the upper surface, and wherein the projections are laminated at corners of both edges on the upper surface of the lower one of the two neighboring circuit boards.