A method for producing a transition metal dichalcogenide-graphene heterojunction composite, the method includes: transferring a graphene onto a flexile substrate; depositing a transition metal layer on the flexible substrate onto which the graphene has been transferred; and injecting a gas containing plasma-treated sulfur (S) onto the flexile substrate onto which the transition metal layer has been deposited, is disclosed.

Provided is a field effect transistor including a gate insulating layer having a two-dimensional material. The field effect transistor may include a first channel layer; a second channel layer disposed on the first channel layer; a gate insulating layer disposed on the second channel layer; a gate electrode disposed on the gate insulating layer; a first electrode electrically connected to the first channel layer; and a second electrode electrically connected to the second channel layer. Here, the gate insulating layer may include an insulative, high-k, two-dimensional material.

An electric field drives nanocrystals dispersed in solvents to assemble into ordered three-dimensional superlattices. A first electrode and a second electrode 214 are in the vessel. The electrodes face each other. A fluid containing charged nanocrystals fills the vessel between the electrodes. The electrodes are connected to a voltage supply which produces an electrical field between the electrodes. The nanocrystals will migrate toward one of the electrodes and accumulate on the electrode producing ordered nanocrystal accumulation that will provide a superlattice thin film, isolated superlattice islands, or coalesced superlattice islands.

A laser sintering deposition method for disposing lead selenide onto a substrate. The method includes: wet-milling a lead selenide ingot mixed with methanol into a colloidal slurry containing nanocrystals; separating the colloidal slurry into nanocrystal particles and the methanol; depositing the nanocrystal particles to a substrate; and emitting coherent infrared light onto the nanocrystal particles for fusing into a lead selenide crystalline film. Afterwards, the lead selenide film can be exposed to oxygen to form a lead selenite layer, and subsequently to iodine gas to produce a lead iodide layer onto the lead selenite layer.

Provided are a superlattice structure including a two-dimensional material and a device including the superlattice structure. The superlattice structure may include at least two different two-dimensional (2D) materials bonded to each other in a lateral direction, and an interfacial region of the at least two 2D materials may be strained. The superlattice structure may have a bandgap adjusted by the interfacial region that is strained. The at least two 2D materials may include first and second 2D materials. The first 2D material may have a first bandgap in an intrinsic state thereof. The second 2D material may have a second bandgap in an intrinsic state thereof. An interfacial region of the first and second 2D materials and an adjacent region may have a third bandgap between the first bandgap and the second bandgap.

Transistors, devices, systems, and methods are discussed related to transistors including 2D material channels and heterogeneous 2D materials on the 2D material channels and coupled to source and drain metals, and their fabrication. The 2D material channels of the transistor allow for gate length scaling, improved switching performance, and other advantages and the heterogeneous 2D materials improve contact resistance of the transistor devices.

Thin film transistors having multi-layer gate dielectric structures integrated with two-dimensional (2D) channel materials are described. In an example, an integrated circuit structure includes a two-dimensional (2D) material layer above a substrate. A gate stack is over the 2D material layer, the gate stack having a first side opposite a second side, and the gate stack having a gate electrode around a gate dielectric structure. A first gate spacer is on the 2D material layer and adjacent to the first side of the gate stack. A second gate spacer is on the 2D material layer and adjacent to the second side of the gate stack, wherein the first gate spacer and the second gate spacer are continuous with a layer of the gate dielectric structure. A first conductive structure is coupled to the 2D material layer and adjacent to the first gate spacer. A second conductive structure is coupled to the 2D material layer and adjacent to the second gate spacer.

Thin film transistors having a spin-on two-dimensional (2D) channel material are described. In an example, an integrated circuit structure includes a first device layer including a first two-dimensional (2D) material layer above a substrate. The first 2D material layer includes molybdenum, sulfur, sodium and carbon. A second device layer including a second 2D material layer is above the substrate. The second 2D material layer includes tungsten, selenium, sodium and carbon.

A method of performing heteroepitaxy comprises exposing a substrate to a carrier gas, a first precursor gas, a Group II/III element, and a second precursor gas, to form a heteroepitaxial growth of one of GaAs, AlAs, InAs, GaP, InP, ZnSe, GaSe, CdSe, InSe, ZnTe, CdTe, GaTe, HgTe, GaSb, InSb, AlSb, CdS, GaN, and AlN on the substrate; wherein the substrate comprises one of GaAs, AlAs, InAs, GaP, InP, ZnSe, GaSe, CdSe, InSe, ZnTe, CdTe, GaTe, HgTe, GaSb, InSb, AlSb, CdS, GaN, and AlN; wherein the carrier gas is Hz, wherein the first precursor is HCl, the Group II/III element comprises at least one of Zn, Cd, Hg, Al, Ga, and In; and wherein the second precursor is one of AsH.sub.3 (arsine), PH.sub.3 (phosphine), H.sub.2Se (hydrogen selenide), H.sub.2Te (hydrogen telluride), SbH.sub.3 (hydrogen antimonide), H.sub.2S (hydrogen sulfide), and NH.sub.3 (ammonia). The process may be an HVPE (hydride vapor phase epitaxy) process.

An integrated circuit includes a two-dimensional transistor having a channel region having lateral ends in contact with first and second source/drain regions. The transistor includes a gate dielectric that is aligned with the lateral ends of the channel region. The transistor includes a gate metal on the gate dielectric. The gate metal has a relatively small lateral overlap of the first and second source/drain regions.