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HgTe nanocrystal-based thin-film transistors (TFTs) with AI2O3 top-gate dielectrics were fabricated on glass substrates using sintered HgTe nanocrystals as the channel layers. To the best of our knowledge, this is the first report on the fabrication of nanocrystal-based TFTs on glass substrates. Colloidal HgTe nanocrystal films were first formed on the glass substrates by spin-coating. The HgTe nanocrystal films were then sintered at 150 °C, leading to a dramatic increase in their conductance, compared with the as-deposited films. The TFTs fabricated in this letter exhibit the typical characteristics of p-channel transistors with a field-effect mobility of 1.04 cm²/V · s, a threshold voltage of +0.2 V, and an ON/OFF current ratio of 1 × 10³. These results suggest that spin-coating and sintering at a low temperature enable the simple and low-cost fabrication of nanocrystal-based TFTs on glass substrates. [ABSTRACT FROM AUTHOR]

Sintered HgTe nanocrystal-based thin-film transistors (TFTs) with bottom- and top-gate geometries were fabricated at a temperature of 150 °C by spin coating in this work. The SiO2 bottom- and Al2O3 top-gate field-effect TFTs with p channels composed of sintered HgTe nanocrystals exhibit high carrier mobilities of 0.82 and 2.38 cm2/V s, respectively. The operating gate voltages for the top-gate transistor with an Al2O3 dielectric layer are actually lower, compared with the SiO2 bottom-gate transistor. The electrical characteristics of these TFTs are discussed in more detail in this letter. [ABSTRACT FROM AUTHOR]

ZnO nanowires were grown between two Au electrodes on an Al2O3-deposited Si wafer. Photoresponse, photoresponse spectrum, and current–voltage (I–V) studies were performed for the investigation into photoconduction mechanism in these nanowires. The photoresponse of the nanowires under the continuous illumination of light with above- or below-gap energies was slow, which indicates that photocurrent in the nanowires is surface-related rather than bulk-related. The photoresponse spectrum represents the above- and below-gap absorption bands for the photocurrents. The I–V characteristics under the illumination of the above-gap light are ohmic, but the characteristics under the illumination of the below-gap light are Schottky. This observation indicates that the above-gap light lowers the potential barrier built in the contact between the ZnO nanowires and electrodes, but that the below-gap light does not lower the potential barrier. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this study we investigate the influence of substrate materials on the electrical characteristics of feedback field-effect transistors (FETs) when subjected to bending fatigue. Each of our transistors are composed of a p+–i–n+ doped silicon nanowire and dual-top metal gates. Feedback FETs on Ecoflex substrates feature outstanding stability compared to those on polyethersulphone and polydimethysiloxane substrates, even at a bending strain of 11.67%. The threshold voltage shift is within the range of 0.3 V, and the on-current only decreases by 15.5% (or less), when compared to the initial flat conditions. Moreover, our devices have outstanding reliability, even after 5000 cycles of repeated bending. [ABSTRACT FROM AUTHOR]

Inthis study, we present the steep switching characteristics of bendablefeedback field-effect transistors (FBFETs) consisting of p–i–n nanowires (NWs) and dual-top-gatestructures. As a result of a positive feedback loop in the intrinsicchannel region, our FBFET features the outstanding switching characteristicsof an on/off current ratio of approximately 106, and pointsubthreshold swings (SSs) of 18–19 mV/dec in the n-channeloperation mode and of 10–23 mV/dec in the p-channel operationmode. Not only can these devices operate in n- or p-channel modes,their switching characteristics can also be modulated by adjustingthe gate biases. Moreover, the device maintains its steep SS characteristics,even when the substrate is bent. This study demonstrates the promisingpotential of bendable NW FBFETs for use as low-power components inintegrated circuits or memory devices. [ABSTRACT FROM AUTHOR]

Abstract: In this study, we demonstrate the photogating effects of p-type HgTe nanoparticles (NPs) on an n-type ZnO nanowire (NW). The photogating effects are due to the charge separation of the charge carriers photogenerated in the NPs under illumination and the subsequent accumulation of the photogenerated electrons in the pn junction of the NPs and the NW. The presence of the electrons in the junction reduces the current in the ZnO NW. The photogating effects are proved by the different photocurrent behavior of the ZnO NW to which the HgTe NPs are attached from that of a bare ZnO NW. In addition, the dependence of the photogating effects on the power of the incident light is discussed. [Copyright &y& Elsevier]