Method for designing power network and power network

A power network comprising:

• a first metal layer, comprising a plurality of first routing tracks, a plurality of first power traces, and a plurality of first vias, wherein said plurality of first power traces are electrically connected to said plurality of first vias;
• a second metal layer, comprising a plurality of second routing tracks and a plurality of second vias, wherein said plurality of second vias are electrically connected to said plurality of first vias;
• and
• a third metal layer, comprising a plurality of third routing tracks, a plurality of third power traces, and a plurality of third vias, wherein said plurality of third power traces are electrically connected to said plurality of second vias and said plurality of third vias,
• wherein a utilization rate of said plurality of first routing tracks is greater than a utilization rate of said plurality of second routing tracks, and said utilization rate of said plurality of second routing tracks is greater than a utilization rate of said plurality of third routing tracks.