International Business Machines Corporation
STACKED NANOSHEET INVERTER

Abstract:

A cross-coupled inverter made of nanolayers from a nanosheet stack structure has a left field effect transistor (FET) stack and a right FET stack. The left FET stack has a second left FET stacked on a first left FET. The first and second left FETs have opposite types. The right FET stack has a second right FET stacked on a first right FET. The first and second right FETs have opposite types. The first left and first right FET have a first common source drain (S/D). The left FET stack has a left gate stack surrounding the one or more first left FET channel layers and the one or more second left FET channel layers. The right FET stack has a right gate stack surrounding the one or more first right FET channel layers and the one or more second right FET channel layers. In some embodiments the left/right gate stack has a left/right center gate stack layer and one or more left/right gate stack layers. The center gate stack layers are thicker than the gate stack layers and are between the first and second FETs. The insulating layer surrounds the middle of the center gate stack layers. The first right FET S/D and the second right FET S/D are internally and electrically connected and connected to a Q external connection. The Q external connection is externally connected to the left gate stack. The first left FET S/D and the second left FET S/D are internally, electrically connected together and connected to a QB external connection. The QB external connection is externally connected to the right gate stack. During operation, the first common S/D is connected to a first external power contact and the second common S/D is connected to a second external power contact and the Q external connection has a logically opposite value of the QB external connection during a desired operation phase. Chip area is reduced because of the low number of external connections required to wire the cross-coupled inverter device.