An electrical contact structure (an MIS contact) includes one or more conductors (M-Layer), a semiconductor (S-Layer), and an interfacial dielectric layer (I-Layer) of less than 4 nm thickness disposed between and in contact with both the M-Layer and the S-Layer. The I-Layer is an oxide of a metal or a semiconductor. The conductor of the M-Layer that is adjacent to and in direct contact with the I-Layer is a metal oxide that is electrically conductive, chemically stable and unreactive at its interface with the I-Layer at temperatures up to 450° C. The electrical contact structure has a specific contact resistivity of less than or equal to approximately 10.sup.−5-10.sup.−7 Ω-cm.sup.2 when the doping in the semiconductor adjacent the MIS contact is greater than approximately 2×10.sup.19 cm.sup.−3 and less than approximately 10.sup.−8 Ω-cm.sup.2 when the doping in the semiconductor adjacent the MIS contact is greater than approximately 10.sup.20 cm.sup.−3.

A semiconductor device includes a source region, a drain region, a core channel region, and a barrier layer. The core channel region is between the source region and the drain region. The barrier layer is between the core channel region and the drain region. The barrier layer is a graded doped barrier layer.

Provided are transistors including an electride electrode. The transistor includes a substrate, a source region and a drain region doped with ions of different polarity from the substrate in a surface of the substrate, a source electrode and a drain electrode including an electride material on the source region and the drain region, a gate insulating layer surrounding the source electrode and a drain electrode on the substrate, and a gate electrode between the source electrode and the drain electrode on the substrate. The source electrode and the drain electrode have an ohmic contact with the substrate.

The present disclosure relates to a method for fabricating a field-effect transistor structure on a substrate. The method includes forming a first semiconductor structure on the substrate, forming above the first semiconductor structure a gate structure that comprises a spacer layer laterally terminating the gate structure and has a lower etch rate than the first semiconductor structure with respect to a predetermined etchant, forming an undercut below the spacer layer by recessing the first semiconductor structure using the etchant, the undercut extending laterally below the spacer layer by not more than the thickness of the spacer layer, forming on the first semiconductor structure a second semiconductor structure filling the undercut, and forming a third semiconductor structure above the first semiconductor structure, wherein one of the second and third semiconductor structures forms the source of the field-effect transistor structure and the other one forms the drain.

One illustrative transistor device disclosed herein includes a gate structure positioned above a semiconductor substrate and a source region and a drain region, each of which comprise an epi cavity with a bottom surface and a side surface. The transistor further includes an interface layer positioned on at least one of the side surface and the bottom surface of the epi cavity in each of the source/drain regions, wherein the interface layer comprises a non-semiconductor material and an epi semiconductor material positioned on at least an upper surface of the interface layer in the epi cavity in each of the source region and the drain region.

A tunneling field effect transistor according to an embodiment of the present invention includes: a first semiconductor layer having a first conductive type; a second semiconductor layer having a second conductive type and realizing a heterojunction with respect to the first semiconductor layer in a first region; a gate insulating layer over the second semiconductor layer in the first region; a gate electrode layer over the gate insulating layer; a first electrode layer electrically connected to the first semiconductor layer; a second electrode layer electrically connected to the second semiconductor layer; and a first insulating layer interposed between the first semiconductor layer and the second semiconductor layer in a second region adjacent to the first region toward the second electrode layer.

A method includes depositing a copper layer over a first substrate, annealing the copper layer, depositing a hexagonal boron nitride (hBN) film on the copper layer, and removing the hBN film from the copper layer. The hBN film may be transferred to a second substrate.

A semiconductor device may include a semiconductor layer, spaced apart source and drain regions in the semiconductor layer with a channel region extending therebetween, and a gate on the channel region. The semiconductor device may further include a body contact in the semiconductor layer and comprising a body contact dopant diffusion blocking superlattice extending through the body contact to divide the body contact into a first body contact region and an second body contact region with the second body contact region having a same conductivity and higher dopant concentration than the first body contact region. The body contact dopant diffusion blocking superlattice may include a respective plurality of stacked groups of layers, with each group of layers comprising a plurality of stacked base semiconductor monolayers defining a base semiconductor portion, and at least one non-semiconductor monolayer constrained within a crystal lattice of adjacent base semiconductor portions.

A semiconductor device is proposed. The semiconductor device includes a group III-N semiconductor layer, an electrically insulating material layer located on the group III-N semiconductor layer, and a metal contact structure located on the electrically insulating material layer. An electrical resistance between the metal contact structure and the group III-N semiconductor layer through the electrically insulating material layer is smaller than 1*10.sup.7 for an area of 1 mm.sup.2. Further, semiconductor devices including a low resistance contact structure, radio frequency devices, and methods for forming semiconductor devices are proposed.

Energy-filtered cold electron devices use electron energy littering through discrete energy levels of quantum wells or quantum dots that are formed through band bending of tunneling barrier conduction band. These devices can obtain low effective electron temperatures of less than or equal to 45K at room temperature, steep electrical current turn-on/turn-off capabilities with a steepness of less than or equal to 10 mV/decade at room temperature, subthreshold swings of less than or equal to 10 mV/decade at room temperature, and/or supply voltages of less than or equal to 0.1 V.