An electrical circuit is disclosed that comprises plurality of tunneling field-effect transistors (TFETs) arranged in a diffusion network matrix having a plurality of nodes wherein, for each of the TFETs that is not on an end of the matrix, a drain of the TFET is electrically coupled with the source of at least one of the other TFETs at a node of the matrix and a source of the TFET is electrically coupled with the drain of at least one of the other TFETs at another node of the matrix. The electrical circuit further comprises a plurality of capacitors, wherein a respective one of the plurality of capacitors is electrically coupled with each node that includes the source of at least one TFET and the drain of at least one TFET. The TFETs may be symmetrical graphene-insulator-graphene field-effect transistors (SymFETs), for example.

A semiconductor device includes an oxide semiconductor layer including a crystalline region over an insulating surface, a source electrode layer and a drain electrode layer in contact with the oxide semiconductor layer, a gate insulating layer covering the oxide semiconductor layer, the source electrode layer, and the drain electrode layer, and a gate electrode layer over the gate insulating layer in a region overlapping with the crystalline region. The crystalline region includes a crystal whose c-axis is aligned in a direction substantially perpendicular to a surface of the oxide semiconductor layer.

Provided are electronic devices and methods of manufacturing same. An electronic device includes an energy barrier forming layer on a substrate, an upper channel material layer on the substrate, and a gate electrode that covers the upper channel material layer and the energy barrier forming layer. The gate electrode includes a side gate electrode portion that faces a side surface of the energy barrier forming layer. The side gate electrode may be configured to cause an electric field to be applied directly on the energy barrier forming layer via the side surface of the energy barrier forming layer, thereby enabling adjustment of the energy barrier between the energy barrier forming layer and the upper channel material layer. The electronic device may further include a lower channel material layer that is provided on the substrate and does not contact the upper channel material layer.

Decrease of the output voltage of the logic circuit is inhibited by raising the gate voltage using a capacitor. In a first transistor, a drain and a gate are electrically connected to a first wiring, and a source is electrically connected to a first node. In a second transistor, a drain is electrically connected to the first node, a source is electrically connected to a second wiring, and a gate is electrically connected to a second node. In a third transistor, a drain is electrically connected to a third wiring, and a source is electrically connected to a third node, and a gate is electrically connected to the first node. In a fourth transistor, a drain is electrically connected to the third node, a source is electrically connected to a fourth wiring, and a gate is electrically connected to the second node. In a capacitor, one electrode is electrically connected to the first node, and the other electrode is electrically connected to the third node. OS transistors are preferably used as the transistors above.

The semiconductor device is manufactured through the following steps: after first heat treatment is performed on an oxide semiconductor film, the oxide semiconductor film is processed to form an oxide semiconductor layer; immediately after that, side walls of the oxide semiconductor layer are covered with an insulating oxide; and in second heat treatment, the side surfaces of the oxide semiconductor layer are prevented from being exposed to a vacuum and defects (oxygen deficiency) in the oxide semiconductor layer are reduced.

Provided is a semiconductor device capable of holding data for a long period. The semiconductor device includes first to third transistors, a capacitor, and a circuit. The third transistor includes a first gate and a second gate. A gate of the first transistor is electrically connected to a first terminal of the capacitor. A first terminal of the first transistor is electrically connected to the second gate. A second terminal of the first transistor is electrically connected to the circuit. A gate of second transistor is electrically connected to a first terminal of the second transistor. A first terminal of the second transistor is electrically connected to the second gate. A second terminal of the second transistor is electrically connected to a first terminal of the capacitor. The circuit is configured to generate a negative potential. A channel formation region of the first transistor preferably includes an oxide semiconductor.

A semiconductor device includes an oxide semiconductor layer including a crystalline region over an insulating surface, a source electrode layer and a drain electrode layer in contact with the oxide semiconductor layer, a gate insulating layer covering the oxide semiconductor layer, the source electrode layer, and the drain electrode layer, and a gate electrode layer over the gate insulating layer in a region overlapping with the crystalline region. The crystalline region includes a crystal whose c-axis is aligned in a direction substantially perpendicular to a surface of the oxide semiconductor layer.

A semiconductor device in which a variation of transistor characteristics is small is provided. The semiconductor device includes a transistor. The transistor includes a first insulator, a first oxide over the first insulator, a first conductor, a second conductor, and a second oxide, which is positioned between the first conductor and the second conductor, over the first oxide, a second insulator over the second oxide, and a third conductor over the second insulator. A top surface of the first oxide in a region overlapping with the third conductor is at a lower position than a position of a top surface of the first oxide in a region overlapping with the first conductor. The first oxide in the region overlapping with the third conductor has a curved surface between a side surface and the top surface of the first oxide, and the curvature radius of the curved surface is greater than or equal to 1 nm and less than or equal to 15 nm.

A transistor that is to be provided has such a structure that a source electrode layer and a drain electrode layer between which a channel formation region is sandwiched has regions projecting in a channel length direction at lower end portions, and an insulating layer is provided, in addition to a gate insulating layer, between the source and drain electrode layers and a gate electrode layer. In the transistor, the width of the source and drain electrode layers is smaller than that of an oxide semiconductor layer in the channel width direction, so that an area where the gate electrode layer overlaps with the source and drain electrode layers can be made small. Further, the source and drain electrode layers have regions projecting in the channel length direction at lower end portions.

A method of forming a substrate contact in a vertical transistor device includes patterning a sacrificial layer to form an opening in the sacrificial layer, the sacrificial layer disposed on hardmask arranged on a substrate, and the substrate including a bulk semiconductor layer, a buried oxide layer arranged on the bulk semiconductor layer, and a semiconductor layer arranged on the buried oxide layer; forming oxide spacers on sidewalls of the opening in the sacrificial layer; using the oxide spacers as a pattern to etch a trench through the substrate, the trench stopping at a region within the bulk semiconductor layer; and depositing a conductive material in the trench to form the substrate contact.