Patent attributes
Aspects of the disclosure provide a semiconductor device and a method for forming the semiconductor device. The semiconductor device includes a first transistor formed in a first region of the semiconductor device. The first transistor includes a first channel structure extending between a source terminal and a drain terminal of the first transistor. The first transistor includes a second channel structure that is stacked on the first channel structure in a vertical direction above a substrate of the semiconductor device. Further, the first transistor includes a first gate structure configured to wrap around the first channel structure and the second channel structure with a first metal cap between the first channel structure and the second channel structure. The first metal cap has a different work function from another portion of the first gate structure.