Herein, a wavelength-selective pyroelectric sensor based on graphene field-effect transistor (gFET) with plasmon-enhanced gate (PG) is reported. The PG gFET (PG-gFET) uses poly(vinylidene fluoride-co-trifluoroethylene) or PVDF-TrFE membrane doped plasmonic nanoparticles as the gate. Gold nanorods (AuNRs) silver (AgNPs) are incorporated into to enhance photothermal conversion efficiency of in sp...

Graphene is a two-dimensional sheet of carbon atoms with numerous envisaged applications owing to its exciting properties. In particular, ultrahigh-speed graphene field effect transistors (GFETs) are possible due to the unprecedented carrier velocities in ideal graphene. Thus, GFETs may potentially advance the current upper operation frequency limit of RF electronics. In this thesis, the practi...

A transition in source-drain current vs. back gate voltage (ID-VBG) characteristics from extrinsic polar molecule dominant hysteresis to anti-hysteresis induced by an oxygen deficient surface layer that is intrinsic to the ferroelectric thin films has been observed on graphene field-effect transistors on Pb0.92La0.08Zr0.52Ti0.48O3 gates (GFET/PLZT-Gate) during a vacuum annealing process develop...

The isolation of the two-dimensional material graphene, a single hexagonal sheet of carbon atoms, is believed to trigger a revolution in electronics. Theory predicts unprecedented carrier velocities in ideal graphene, from which ultrahigh speed graphene field effect transistors (GFETs) are envisioned. In this thesis, the prospects of GFETs for microwave receivers are investigated with the empha...

Sensing of DNA by graphene-on-silicon FET structures at DC and 101GHz Report Title A graphene–silicon field-effect transistor (GFET) structure is demonstrated as a detector of single-stranded 13-mer DNA simultaneously at DC and 101 GHz at three different molarities: 0.01, 1.0 and 100 nM. The mechanism for detection at DC is the DNA-induced change in lateral sheet conductance, whereas at 101 GHz...

Selective and rapid detection of biomarkers is of utmost importance in modern day health care for early stage diagnosis to prevent fatal diseases and infections. Among several protein biomarkers, the role of lysozyme has been found to be especially important in human immune system to prevent several bacterial infections and other chronic disease such as bronchopulmonary dysplasia. Thus, real-ti...

Detection of disease-related gene expression by DNA hybridization is a useful diagnostic method. In this study a monolayer graphene field effect transistor (GFET) was fabricated for the detection of a particular single-stranded DNA (target DNA). The probe DNA, which is a single-stranded DNA with a complementary nucleotide sequence, was directly immobilized onto the graphene surface without any ...

Using a graphene field-effect transistor biosensor, we monitored the pH inside a living biofilm with fast temporal resolution (∼1 s) over multihour time periods. The atomically thin sensor is positioned between the biofilm and a supporting silicon oxide surface, providing noninvasive access to conditions at the base of the biofilm. We determine the transient changes in pH when the biofilm metab...

While graphene transistors have proven capable of delivering gigahertz-range cutoff frequencies, applying the devices to RF circuits has been largely hindered by the lack of current saturation in the zero band gap graphene. Herein, the first high-frequency voltage amplifier is demonstrated using large-area chemical vapor deposition grown graphene. The graphene field-effect transistor (GFET) has...

A high performance hybrid broadband photodetector with graphene/nitrogen-functionalized graphene quantum dots (NGQDs@GFET) is developed using boron nitride nanosheets (BN-NSs) as a buffer layer to facilitate the separation and transport of photoexcited carriers from the NGQD absorber. The NGQDs@GFET photodetector with the buffer layer of BN-NSs exhibits enhanced photoresponsivity and detectivit...