| abstract |
The electronic structure includes an electronic device coupled to the substrate by conductive bumps and ball limiting metallurgy (BLM). The underfill material with filler particles is disposed in the space between the electronic device and the substrate. The weight percentage of filler particles is at least about 60%. The particle size of at least 90 wt% of the filler particles is less than approximately 2 μm and / or the filler particles are coated with an organic binder. Once the underfill material is sufficiently cured, its coefficient of thermal expansion is 30 PPM / ° C or lower, its glass transition temperature is 100 ° C or higher, and its adhesion to the passivation layer of the electronic device, the substrate at its edge and the electronic device is ball limiting. The electronic structure can pass the standardized reliability test without delamination of metallurgy.n n n n Underfill Materials, Filler Particles, Organic Binders |