Method of Flip-Chip Assembly of Two Electronic Components by UV Annealing, and Assembly Obtained

摘要

The invention concerns a method of flip-chip assembly between first (1) and second (2) components each comprising connection pads (11, 21) on one of the faces of same, referred to as assembly faces, which involves transferring the components onto each other via the assembly faces of same in such a way as to create electrical interconnections between the pads of the first and second components. The invention involves transforming the copper oxide into copper by UV annealing, very locally, in the gap between the components, at least around the areas adjacent to the connection pads. The method according to the invention can be used for any component that is transparent to UV rays, including for substrates made from a plastic material such as substrates made from PEN or PET. The invention also concerns the assembly of two components obtained by the method.

主权项

1. A process for flip-chip assembly of a first component and a second component, each component including connection pads on one of their faces, called their assembly faces, in which the components are added one to the other via their assembly faces so as to produce electrical interconnections between the pads of the first and those of the second component, the process including the following steps:
a/ producing the first component with its connection pads, the first component being made of a material that is transparent to ultraviolet (UV) radiation in zones, called emission zones, each of said emission zones being defined around a pad, the pads of the first component being made of a material that absorbs or reflects UV radiation; b/ depositing copper oxide (CuO) on the first component at least on its connection pads and in the emission zones; c/ producing the second component with its connection pads, the connection pads of the second component being made of a material that reflects UV radiation, each of said pads being suitable for reflectively focusing ultraviolet radiation arriving from an emission zone onto one of the pads of the first component, and, depending on the circumstances, onto each metal protuberance formed on a pad of the second component; d/ forming interconnection metal protuberances on at least some of the pads of the second component; e/ aligning the first and second components and adding them one to the other via their assembly faces; and f/ applying UV radiation through the emission zones of the first component to the deposited copper oxide so as to carry out a UV anneal that converts the deposited copper oxide into copper and, depending on the circumstances, makes the interconnection protuberances melt.