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This work presents the effect of Al mole fraction and gate oxide on the direct current and low frequency noise characterization of GaN/AlGaN high electron mobility transistor (HEMT). Metal–oxide–semiconductor (MOS)-HEMT with SiO2 in the gate stack improved the Id(on)/Id(off) ratio up to more than 8 orders, compared to fabricated HEMT without oxide. It was shown that the gate leakage and isolation leakage suppression efficiency improved dramatically with the gate oxide. Subthreshold swing of MOS-HEMTs with different Al mole fractions (from 20% to 35%) varies slightly from 72 mV/decade to 79 mV/decade. Low frequency noise study revealed the difference in transport mechanism between HEMT and MOS-HEMTs. By using carrier number fluctuation model on the measured data, it was found that the noise is predominantly coming from the surface states. While generation-recombination is very prominent in HEMT, it is very insignificant in both MOS-HEMTs at much higher frequencies. This study reveals that very high number of surface states, assisting the tunneling in Schottky/AlGaN barrier is responsible for unusually high leakage and higher noise level in HEMT without oxide. Leakage level is improved from mA/mm range for HEMT to pA/mm range for MOS-HEMTs. Leakage suppression improvement and minimization of noise level can be mainly attributed by to high quality SiO2. Hooge's constant was on the order of 5–6 × 10−3, which is 5 × 10−2 for HEMT without oxide.

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Recent studies have shown superior thermal transport of graphene on copper as a potential candidate for the next generation interconnects. Using density function theory (DFT) we have studied the current transport of graphene/copper (G/Cu) hybrid-nano wire interconnect system and compared with graphene interconnect. From the first principle calculation, band structure and density of states have been calculated. Using Landauer-Buttiker (LB) formalism, electrical transport is calculated. For this presented G/Cu system, we found resistivity as 1.25x10-6 Ω-m, which is one tenth of Cu-bulk resistivity. G/Cu hybrid interconnect shows more conductive than graphene only interconnect for low bias applications.

Stable room temperature operation of field effect transistor (FET) based on two-dimensional silicon (silicene) has recently been reported. Like graphene, silicene is a Dirac cone material. Silicene-based devices provide high off-state leakage current due to lack of a significant bandgap. However, quantum confined silicene nanoribbon (SiNR) shows observable bandgap which can be used for making switching transistors for digital integrated circuit design. Contrary to metal oxide semiconductor FET (MOSFET), tunnel field effect transistor (TFET) overcomes the physical limit of scaling of supply voltage. In this work, we present structure and characteristics of SiNR TFET using atomistic simulation based on self-consistent solution of 3D Poisson and Schrödinger equations within the non-equilibrium Green’s function (NEGF) formalism. Performances are also compared with the International Technology Roadmap for Semiconductors (ITRS) projected high performance requirements of 2026 nMOSFETs.