Chip on flex and flip chip on flex technology

Abstract

The outline of this project is to look at the design concept, material review and the process capabilities and requirements for the COF and manufacturing. Various problems pertaining to the reliability of the COF assemblies at the various stages of the processes have also been highlighted. In the wire bonding process, substrate material variations, such as the gold lead surface roughness and the present of contamination have been cited as major reliability issues, which will affect the process consistency and reliability of the bonded wires. Such phenomena are clearly shown by the various scanning electron microscope (SEM) photographs. In addition, the presence of voids during encapsulation and after cure can result in mechanical failures when subjected to the various reliability tests. Various experiments have been carried out to characterize and optimize the various parameters for product reliability.