Inorganic dopants inspire n-type graphene transistor progress

Researchers in India have made graphene field-effect transistors based on discrete inorganic structures that reportedly work for over 10 months. The approach has led them to produce a graphene logic inverter that is stable in ambient conditions.

Inorganic dopants inspire n-type graphene transistor progress image

Conventional electronics are silicon based, due to the ease of doping silicon with either electrons or holes. These two forms of silicon, n- and p-type, are the building blocks of electronic devices. However, it isn’t possible to make silicon electronics on the nanoscale, so many researchers are turning to materials like graphene.

Paragraf starts producing graphene at commercial scale

Paragraf logo imageUniversity of Cambridge spin-out company, Paragraf, recently announced that it started producing graphene at up to eight inches (20cm) in diameter, large enough for commercial electronic devices.

Paragraf is producing graphene ‘wafers’ and graphene-based electronic devices, which could be used in transistors, where graphene-based chips could deliver speeds more than ten times faster than silicon chips; and in chemical and electrical sensors, where graphene could increase sensitivity by a factor of more than 30. The company’s first device will reportedly be available in the next few months.

Graphene quantum dots to help create single electron transistors

Scientists from Manchester University, the Ulsan National Institute of Science & Technology and the Korea Institute of Science and Technology have developed a novel technology, which combines the fabrication procedures of planar and vertical heterostructures in order to assemble graphene-based single-electron transistors.

Graphene quantum dots to help create single electron transistorsThe schematic structure of the devices

In the study, it was demonstrated that high-quality graphene quantum dots (GQDs), regardless of whether they were ordered or randomly distributed, could be successfully synthesized in a matrix of monolayer hexagonal boron nitride (hBN). Here, the growth of GQDs within the layer of hBN was shown to be catalytically supported by the platinum (Pt) nanoparticles distributed in-between the hBN and supporting oxidised silicon (SiO2) wafer, when the whole structure was treated by the heat in the methane gas (CH4). It was also shown, that due to the same lattice structure (hexagonal) and small lattice mismatch (~1.5%) of graphene and hBN, graphene islands grow in the hBN with passivated edge states, thereby giving rise to the formation of defect-less quantum dots embedded in the hBN monolayer.

Korean researchers fabricate ordered graphene quantum dot arrays

A new study led by the Ulsan National Institute of Science and Technology in South Korea reveals a technology capable of fabricating highly ordered arrays of graphene quantum dots.

Korean researchers fabricate ordered graphene quantum dot arrays imageGraphene quantum dots of various sizes in a stable, ordered array

The research team demonstrated a novel way of synthesizing GQDs, embedded inside a hexagonal boron nitride (hBN) matrix. Thus, they demonstrated simultaneous use of in-plane and van der Waals heterostructures to build vertical single-electron tunneling transistors.

Italian researchers develop a graphene-based OFET for future OLED and OLET displays

Researchers from Italy's ISOF-CNR, University of Naples "Federico II" and Università di Modena e Reggio Emilia have developed new organic n-type FET transistors (OFETs) based on CVD graphene sheets. The researchers say that the new process and materials they used can enable flexible, transparent and short-channel OFETs - which could be used in the future for OLED or OLET (organic light emitting transistor) displays.

ISOF CNF CVD graphene OFET structure photo

To create the new transistors, the researchers used thermally evaporated thin-films of PDIF-CN2 (a perylene diimide derivative) as the the organic semiconductor for the active channel of the transistor with the single-layer CVD graphene (grown at Italy's IIT institute) as the electrode material. The final device architectures have been fabricated via Electron-Beam-Lithography (EBL) and Reactive Ion Etching (RIE).

Versarien - Think you know graphene? Think again! Versarien - Think you know graphene? Think again!