InFO is currently the smallest packaging option in the X-Y direction, as well as the Z direction, which refers to height. It is best suited for very area constrained applications that need the smallest packaging option. Thermally, this package option is very similar to bare die packages. However, due to how thin the package is, an additional step to edge bond the component to the board is required. InFO packages also require less asserted pressure by the thermal solution. This could increase cost and make assembly difficult. The following figure shows the cross section and top view of a ZU3P InFO package.
Figure 1. ZU3P InFO Package
