Self-aligned metal gate for multigate device and method of forming thereof

A device, comprising:

• a first channel layer disposed between first source/drain features over a substrate;
• a first metal gate that surrounds the first channel layer;
• a second channel layer disposed between second source/drain features over the substrate;
• a second metal gate that surrounds the second channel layer;
• a dielectric fin disposed between and separating the first metal gate and the second metal gate;
• a first portion of a conductive layer over the first metal gate;
• a second portion of the conductive layer over the second metal gate;
• and
• an isolation layer between the first portion and second portion of the conductive layer and over the dielectric fin, wherein at least one of the first portion of the conductive layer or the second portion of the conductive layer includes a rounded terminal end abutting the isolation layer.

A method including,

• forming a first gate structure, a first source structure and a first drain structure of a first gate all around (GAA) device over a substrate;
• forming a second gate structure, a second source structure and a second drain structure of a second GAA over the substrate, wherein a dielectric fin is disposed between the first gate structure and the second gate structure;
• depositing a dummy layer over the first gate structure, the second gate structure, and the dielectric fin;
• patterning the dummy layer to form a trench within the dummy layer over the dielectric fin;
• filling the trench with a dielectric material to form a dielectric feature;
• removing the patterned dummy layer after filling the trench;
• and
• depositing at least one conductive layer having a first portion over the first gate structure and a second portion of the second gate structure, wherein the dielectric feature interposes the first and second portion.