A transistor comprising: a substrate; a first electrically conductive material layer positioned on the substrate, a second electrically conductive material layer in contact with and positioned on the first electrically conductive material layer, a third electrically conductive material layer in contact with and positioned on the second electrically conductive material layer, the third electrically conductive material layer overhanging the second electrically conductive material layer on a first side and on a second side opposite to the first side such that the second conductive layer and the third conductive layer define reentrant profiles on the first and second sides, and the first electrically conductive material layer extending beyond the second electrically conductive material layer on both the first and second sides to provide electrical conduction under the reentrant profiles, the first, second and third electrically conductive material layers (120; 130; 140) defining a gate electrode structure; an electrically insulating material layer conformally positioned over exposed portions of the third electrically conductive material layer, the second electrically conductive material layer, the first electrically conductive material layer, and at least a portion of the substrate; and a semiconductor material layer that conforms to and is in contact with the electrically insulating material layer; an electrically conductive material layer defining first and second electrodes positioned over and in contact with the semiconductor material layer beyond the first and second sides of the gate electrode structure; and an electrically conductive material layer defining a third electrode positioned over and in contact with the semiconductor material layer over the gate electrode structure, wherein at least a portion of a semiconductor material channel is located in each of the reentrant profiles on the first and second sides. a substrate; a first electrically conductive material layer positioned on the substrate, a second electrically conductive material layer in contact with and positioned on the first electrically conductive material layer, a third electrically conductive material layer in contact with and positioned on the second electrically conductive material layer, the third electrically conductive material layer overhanging the second electrically conductive material layer on a first side and on a second side opposite to the first side such that the second conductive layer and the third conductive layer define reentrant profiles on the first and second sides, and the first electrically conductive material layer extending beyond the second electrically conductive material layer on both the first and second sides to provide electrical conduction under the reentrant profiles, the first, second and third electrically conductive material layers (120; 130; 140) defining a gate electrode structure; an electrically insulating material layer conformally positioned over exposed portions of the third electrically conductive material layer, the second electrically conductive material layer, the first electrically conductive material layer, and at least a portion of the substrate; and a semiconductor material layer that conforms to and is in contact with the electrically insulating material layer; an electrically conductive material layer defining first and second electrodes positioned over and in contact with the semiconductor material layer beyond the first and second sides of the gate electrode structure; and an electrically conductive material layer defining a third electrode positioned over and in contact with the semiconductor material layer over the gate electrode structure, wherein at least a portion of a semiconductor material channel is located in each of the reentrant profiles on the first and second sides.