US Patent 11664333 Method of manufacturing die seal ring

A method of manufacturing a die seal ring including the following steps is provided. A dielectric layer is formed on a substrate. Conductive layers stacked on the substrate are formed in the dielectric layer. Each of the conductive layers includes a first conductive portion and a second conductive portion. The second conductive portion is disposed on the first conductive portion. A width of the first conductive portion is smaller than a width of the second conductive portion. A first air gap is formed between a sidewall of the first conductive portion and the dielectric layer. A second air gap is formed between a sidewall of the second conductive portion and the dielectric layer.