To minimize the chip power consumption, even small packages now have to handle multiple power lines in limited space resources. For example, single trunk of power ring should be shared by 2+ power lines (above figure, left), single power plane should be divided into multiple islands (above figure, right). Therefore, such power/ground structure should come first to start the interposer design. On the other hand, the power plane is the last object that can be designed in interposer design since it should avoid other net objects intruded on the island. Considering this situation, GemPackage provides convenient function for chip designers to make/cut power/ground rings, and to roughly design the plane islands. The information is always visible through out the interposer design so that PCB designer can place vias and traces considering the power/ground structure. GemPackage also provides a simple way to fill inside the plane, avoiding intruders, to produce realistic figures in the design review meeting. (above figure right).