The present disclosure provides a semiconductor device, a semiconductor assembly and method of manufacturing the semiconductor assembly. The semiconductor device includes a substrate, a conductive feature in the substrate, an isolation liner between the substrate and the conductive feature, and a main component in the substrate. The conductive feature includes first to third blocks. The first block has a uniform first critical dimension, wherein the main component is disposed around the first block. The second block has a uniform second critical dimension greater than the first critical dimension. The third block is interposed between the first block and the second block and has varying third critical dimensions.