Dual-gate vtft

An electronic device comprising:

• a substrate;
• an electrically conductive gate structure on the substrate, the electrically conductive gate structure extending away from the substrate to a top, the top extending beyond a first edge to define a first reentrant profile, wherein the electrically conductive gate structure includes an insulating vertical-support-element and a conformal conductive bottom-gate layer in the first reentrant profile;
• a first conformal dielectric layer that maintains the first reentrant profile and is in contact with the electrically conductive gate structure and at least a portion of the substrate;
• a conformal semiconductor layer that maintains the first reentrant profile and is in contact with the conformal dielectric layer;
• a first electrode located in contact with a first portion of the semiconductor layer over the top of the electrically conductive gate structure;
• a second electrode located in contact with a second portion of the semiconductor layer, over the substrate and not over the top of the electrically conductive gate structure, and adjacent to the first edge of the electrically conductive gate structure, wherein the first electrode and second electrode are spaced apart by a distance, the distance between the first electrode and the second electrode being greater than zero when measured orthogonally to a surface of the substrate;
• a second conformal dielectric layer on the semiconductor layer in the first reentrant profile;
• and
• a conformal conductive top-gate on the conformal dielectric layer in the first reentrant profile, wherein the first electrode and the second electrode define a semiconductor channel of a dual-gate transistor, at least a portion of the semiconductor channel extending in a direction orthogonal to the surface of the substrate in the first reentrant profile.