US Patent 12008302 Integrated circuit with thicker metal lines on lower metallization layer

An IC structure includes first, second, third, and fourth transistors on a substrate, a first net and a second net. The first net includes a plurality of first metal lines routed on a first metallization layer, and a plurality of first metal vias electrically connecting the plurality of first metal lines to the first and second transistors. The second net includes a plurality of second metal lines routed on a second metallization layer, and a plurality of second metal vias electrically connecting the plurality of second metal lines to the third and fourth transistors. A count of the first metal vias of the first net is less than a count of the second metal vias of the second net, and a line height of the first metal line of the first net is greater than a line height of the second metal line of the second net.