US Patent 11699760 Contact structure for stacked multi-gate device

A semiconductor device according to the present disclosure includes a stack of first channel members, a stack of second channel members disposed directly over the stack of first channel members, a bottom source/drain feature in contact with the stack of the first channel members, a separation layer disposed over the bottom source/drain feature, a top source/drain feature in contact with the stack of second channel members and disposed over the separation layer, and a frontside contact that extends through the top source/drain feature and the separation layer to be electrically coupled to the bottom source/drain feature.