Technique and structure for making convex

Abstract

This invention relates to cam creation technique and its structure. It includes a sheath with flat surface, the sheath is covered on a joint mat on the plaque to form a contact surface with one open through the sheath, and one cam on the contact surface and the flat surface is formed. The contact mat can be reduced because of the flat surface of the sheath. The mechanical strength of the sheath on the contact mat is strengthened; the cam will has large efficient area when stitching. Selecting space of different directivity conduction membrane is large, short circuit and electric leakage probability is little, so the stitching good ratio and conducting quality of the cam is improved.

Description

technical field [0001] The present invention relates to a manufacturing process and structure of a bump, in particular to a manufacturing process and structure of a planarized bump. Background technique [0002] Wire bonding, tape automatic bonding (TAB) and flip chip (flip chip) bonding are typical technologies for integrated circuit (IC) packaging. Generally speaking, wire bonding is used in low-density wiring packages with less than about 300 contacts, high-connection-density packages for TAB applications reach about 600 contacts, and flip-chip bonding provides higher connection density packages with more than 600 contacts. . Packages that use flip-chip bonding must first grow bumps on the bonding pads of the IC in order to attach chips to glass (Chip On Glass; COG), chip bonding circuit boards (Chip On Board; COB), and chip bonding. Lamination is performed in Chip On Film (COF) or other packaging procedures. In order to reduce telecommunication interference, increase ...

AI Technical Summary

Problems solved by technology

During lamination, the conductive particles 56 in the bump gap 54 are easily squeezed and deformed due to their large particle size, resulting in short circuit and leakage between adjacent bumps 22, resulting in low lamination yield.

If conductive particles 52 with a smaller particle size are used, a good connection between the bump 22 and the wire 48 cannot be provided, so the known technology has insurmountable difficulties

With the reduction of IC size and the demand for high I / O count, the bonding pads 14 of the IC are also reduced, and the effective area 32 is thus reduced, resulting in a reduction in the bonding yield and the conductive quality after bonding.

Furthermore, a natural disadvantage of the flip-chip package is that the mechanical strength of the edge region 58 of the bump 22 is weak, and it is easy to be broken due to lateral pulling.

However, in order to obtain a smaller roughness h on the surface of the bump 22, the height of the step 28 must be reduced, so the thickness of the sheath 16 is thinner, and the disadvantage of weaker mechanical strength cannot be overcome.

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