An ESD protection structure and a semiconductor device having an ESD protection structure with the ESD protection structure including a patterned conductive ESD protection layer. The ESD protection layer is patterned to have a first portion of a substantially closed ring shape having an outer contour line and an inner contour line parallel with each other. The outer and the inner contour lines are waved lines. The first portion further has a midline between and parallel with the outer and the inner contour lines. The midline is a waved line having a substantially constant curvature at each point of the midline. Therefore the ESD protection layer has a substantially uniform curvature and an increased perimeter which advantageously improve the breakdown voltage and the current handling capacity of the ESD protection structure.