Method of manufacturing a effect transistor using carbon nanotubes and a field effect transistor

A semiconductor device having a gate-all-around field effect transistor (GAA FET), comprising:

• a first GAA FET;
• and
• a second GAA FET, wherein:
• each of the first GAA FET and the second GAA FET includes:
• a plurality of layers arranged along a first direction, each layer including a plurality of carbon nanotubes (CNTs) arranged along a second direction perpendicular to the first direction disposed over a substrate;
• a gate structure, including a gate electrode, formed around the CNTs in a channel region;
• and
• a source/drain contact formed around the CNTs in a source/drain region,
• wherein the first GAA FET and the second GAA FET share the gate electrode,
• the CNTs have an average diameter DCNT and a pitch PH along the second direction, and the pitch is DCNT≤PH≤(10×DCNT), and
• adjacent CNTs in at least one of the plurality of layers are in contact with each other.

A semiconductor device having a gate-all-around field effect transistor, comprising:

• carbon nanotubes (CNTs) disposed over a substrate;
• a gate structure formed around the CNTs in a channel region;
• and
• a source/drain contact formed around the CNTs in a source/drain region, wherein:
• the CNTs are arranged in multiple layers,
• adjacent CNTs in at least one of the multiple layers are in contact with each other, and
• a vertical pitch P between adjacent layers is 0.9×PA≤P≤1.1×PA, where PA is an average pitch of the multiple layers.