FABRICATION OF GATE-ALL-AROUND INTEGRATED CIRCUIT STRUCTURES HAVING ADDITIVE GATE STRUCTURES

Gate-all-around integrated circuit structures having additive gate structures are described. For example, an integrated circuit structure includes a first vertical arrangement of horizontal nanowires, and a second vertical arrangement of horizontal nanowires. A P-type gate stack is over the first vertical arrangement of horizontal nanowires, the P-type gate stack having a P-type conductive layer over a first gate dielectric, and an intervening conductive seed layer between the P-type conductive layer and the first gate dielectric. An N-type gate stack is over the second vertical arrangement of horizontal nanowires, the N-type gate stack having an N-type conductive layer over a second gate dielectric, and the intervening conductive seed layer between the N-type conductive layer and the second gate dielectric. The P-type gate stack is in contact with the N-type gate stack.