A novel type of stacked cylindrical PoP package

With the reduction in size and weight for electronic products, particularly for accurate manufactures, the IC boards used to achieve complex circuit functions become smaller and lighter. It is also needed to make the board thin. The layers stacking assembly together will be more important, but the precision requirements of the device can not be reduced, either. The purpose of the stacked vertical interconnect is system miniaturization and smaller. This paper presents the IC in the internal of the device, planting copper pillars on one side to achieve the connection of the signal, the power and the ground. The copper pillars can make the connection more stable and the signal transmission better. The length of the copper pillar is easier to control, and the copper pillar under the heat of the board will generate little change in the length or other properties. The novel method meets both the signal transmission and securely connection between each device, and will not make the connectors bridged together.