A device includes a transistor, an insulating structure, a buried conductive line, and a buried via. The transistor is above a substrate and includes a source/drain region and a source/drain contact above the source/drain region. The insulating structure is above the substrate and laterally surrounds the transistor. The buried conductive line is in the insulating structure and spaced apart from the transistor. The buried via is in the insulating structure and interconnects the transistor and the buried conductive line. A height of the buried conductive line is greater than a height of the source/drain contact.