A New Species of IC Package: Via-interconnect Ball-Grid-Array (ViB)

ViB, Via-interconnect Ball-Grid-Array, is a new package species which is denominated first in the industry in this paper. This new species involves a new chip-to-package interconnect technology named via-interconnect. Some of WLPs (Wafer Level Packages) and recently developed so-called "fan-out" packages belong to this category. The definition of ViB is a ball-grid-array package whose chip-to-package electrical interconnect is done by "via". The via is a channel formed between chip I/O pads and package inner bonding pads, followed by conductive material filled into the via or metallization done on the sidewall and bottom of the via to electrically connect the die and package. Thus, the assembly process, production equipment, and interconnect failure mechanism of the ViB may be very different from the conventional wire-bonding package, flip-chip-bonding package, and tape-automatic-bonding package. Therefore, from packaging taxonomy point of view, there is a need to differentiate via-interconnect from the conventional technologies. The categorization of chip-to-package interconnect is re-examined in this paper, and the via-interconnect is proposed to be added as a new category.