Highly purified semiconducting carbon nanotube (CNT) thin films and graphene are used to fabricate hybrid photodetector. The results indicate that the hot carriers generated in graphene can tunnel into bottom CNT film through nanometer thick silicon film when illuminated. As a result, electrons and holes are accumulated at separated side of the silicon layer, resulting in a modulation of the current in the CNT film transistor due to the photogating effect. The photodetector shows a responsivity of 83 mA/W for visible light (633 nm) and a good response within the near-infrared range. Such CNT film-graphene photodetector, taking advantages of both broadband absorption of graphene and small dark current of semiconducting CNTs, paves the way to future high performance infrared photodetectors.

This paper reports on methods and examples of in-situ field emission measurements of individual one-dimensional nanostructures based on scanning electron microscope (SEM) and nanoprobe techniques. In the experimental setup, tungsten (W) tips and nanostructures acted as electron-receivers and emitters, respectively, based on which systematic studies of individual MWCNTs and ZnO nanowires were realized. By combining real-time imaging, nanoprobe technique for precise nanomanipulation and electric measurement, and light input, experiments were performed to study the influences of the receiver-emitter distance, morphology variation, adsorbed gas molecules, and laser irradiation. Results demonstrate that when D << 3L (L is the length of nanostructures), the turn-on fields and threshold fields increase with the decreasing D, indicating degraded field emission property. Besides, the increased curvature radius of nanostructures results in reduced field enhancement factor and field emission property. In addition, desorption of oxygen molecules and laser radiation improve the field emission properties of nanostructures.

Carbon nanotube based CMOS (complementary metal-oxide-semiconductor) field effect transistor inverters were modeled through SPICE(simulation program with integrated ciruit emphasis) by using table-lookup model. Simulation results were verified by the experimental results and good agreement was achieved. The effects of supplied voltage and the threshold voltage to the power and the delay characteristics of the inverters were investigated by DC analysis and TRAN analysis, and optimum strategy was given. In addition, optimum strategies for NOR and NAND logic circuits were given by the simulation using the semi-empirical table-lookup model.