The Research On The Calculation Of ACA Contact Resistance Of Interconnect Interface

In the field of electronic packaging, flip-chip bonding technology develops so rapidlythat the demanding requirements of high-density packaging can be gradually satisfied.Researchers on high-density packaging pursue line array、area array in the field of the formof bumps and2D、3D in the field of the structure of chips. The line array means the pinsdistributed by four sides of chip to achieve the purpose of high density; The area array (BGA)means that the spherical pins are arranged like grid pattern to achieve the purpose of highdensity.2D high density could be achieved by reducing the characteristic dimensions ofbumps, thus enabling the maximum number of joints on a single chip. On the other hand,researches on3D high density usually advance the density in the Z-direction by thinning thechip and substrate, minimizing the height of bumps and pads with adopting advancedpackaging process. The thesis focus on2D、line array high-density chip.Firstly, the thesis carries out the simulation of compression deformation of theconductive particles through the software COMSOL. Then the thesis calculates the resistanceof conductive particles under different compression deformation by the simulation and fits thefunction. Also, combined with the experimental results, the actual conductive particles aredivided into four categories according to the compression deformation.Secondly, the thesis carries out a crossover experiment with different process parameters.Then the thesis establishes model of flip-chip solder contact resistance R (N1, N2, N3, N4)through capture/deformation of four categories of conductive particles watched by themicroscope and the resistance measured four-point probe. Also, the thesis gets the best processparameters of chip and substrate used in the experiment.Finally, the thesis discusses the impact of characteristic of bump on the capture ofconductive particles. The thesis discoveries that the capture of conductive particles hasproportional relationship with their areas, and the ratio of the areas of bump and gap and theratio of the number of the conductive particles has power relationship. The thesis alsodiscoveries the "escape" line of conductive particles after bonding.