基礎講座 電気泳動(Electrophoresis)

Transparent electronics is today one of the most advanced topics for a wide range of device applications. The key components are wide bandgap semiconductors, where oxides of different origins play an important role, not only as passive component but also as active component, similar to what is observed in conventional semiconductors like silicon. Transparent electronics has gained special attention during the last few years and is today established as one of the most promising technologies for leading the next generation of flat panel display due to its excellent electronic performance. In this paper the recent progress in n- and p-type oxide based thin-film transistors (TFT) is reviewed, with special emphasis on solution-processed and p-type, and the major milestones already achieved with this emerging and very promising technology are summarizeed. After a short introduction where the main advantages of these semiconductors are presented, as well as the industry expectations, the beautiful history of TFTs is revisited, including the main landmarks in the last 80 years, finishing by referring to some papers that have played an important role in shaping transparent electronics. Then, an overview is presented of state of the art n-type TFTs processed by physical vapour deposition methods, and finally one of the most exciting, promising, and low cost but powerful technologies is discussed: solution-processed oxide TFTs. Moreover, a more detailed focus analysis will be given concerning p-type oxide TFTs, mainly centred on two of the most promising semiconductor candidates: copper oxide and tin oxide. The most recent data related to the production of complementary metal oxide semiconductor (CMOS) devices based on n- and p-type oxide TFT is also be presented. The last topic of this review is devoted to some emerging applications, finalizing with the main conclusions. Related work that originated at CENIMAT|I3N during the last six years is included in more detail, which has led to the fabrication of high performance n- and p-type oxide transistors as well as the fabrication of CMOS devices with and on paper.

Oxide Semiconductor Thin‐Film Transistors: A Review of Recent Advances

The semiconductor industry has been able to improve the performance of electronic systems for more than four decades by making ever-smaller devices. However, this approach will soon encounter both scientific and technical limits, which is why the industry is exploring a number of alternative device technologies. Here we review the progress that has been made with carbon nanotubes and, more recently, graphene layers and nanoribbons. Field-effect transistors based on semiconductor nanotubes and graphene nanoribbons have already been demonstrated, and metallic nanotubes could be used as high-performance interconnects. Moreover, owing to the excellent optical properties of nanotubes it could be possible to make both electronic and optoelectronic devices from the same material.

Carbon-based electronics.

Based on the achievement of synthesis of ZnO nanowires in mass production, ZnO nanowires gas sensors were fabricated with microelectromechanical system technology and ethanol-sensing characteristics were investigated. The sensor exhibited high sensitivity and fast response to ethanol gas at a work temperature of 300 °C. Our results demonstrate the potential application of ZnO nanowires for fabricating highly sensitive gas sensors.

Fabrication and ethanol sensing characteristics of ZnO nanowire gas sensors

Synthesis of carbon nanotubes by chemical vapor deposition over patterned catalyst arrays leads to nanotubes grown from specific sites on surfaces. The growth directions of the nanotubes can be controlled by van der Waals self-assembly forces and applied electric fields. The patterned growth approach is feasible with discrete catalytic nanoparticles and scalable on large wafers for massive arrays of novel nanowires. Controlled synthesis of nanotubes opens up exciting opportunities in nanoscience and nanotechnology, including electrical, mechanical, and electromechanical properties and devices, chemical functionalization, surface chemistry and photochemistry, molecular sensors, and interfacing with soft biological systems.

/pdf/carbon-nanotubes-synthesis-integration-and-properties-1kq36jxaj3.pdf

Carbon Nanotubes: Synthesis, Integration, and Properties

In2O3 nanowire transistors were used to investigate the chemical gating effect of organic molecules and biomolecules with amino or nitro groups. The nanowire conductance changed dramatically after adsorption of these molecules. Specifically, amino groups in organic molecules such as butylamine, donated electrons to In2O3 nanowires and thus led to enhanced carrier concentrations and conductance, whereas molecules with nitro groups such as butyl nitrite made In2O3 nanowires less conductive by withdrawing electrons. In addition, intrananowire junctions created by partial exposure of the nanowire device to butyl nitrite were investigated, and pronounced rectifying current–voltage characteristics were obtained. Furthermore, chemical gating by low-density lipoprotein cholesterol, the offending agent in coronary heart diseases, was also observed and attributed to the amino groups carried by the bio species.

Chemical gating of In2O3 nanowires by organic and biomolecules

Chemical Gating of In2O3 Nanowires by Organic and Bio Molecules

Chemical vapor deposition (CVD) using gold nanoparticles as the catalyst to grow high-quality single-crystal gallium nitride nanowires was developed. This method enables control over several important aspects of the growth, including control of the nanowire diameter by using monodispersed gold clusters, control of the nanowire location via e-beam patterning of the catalyst sites, and control of the nanowire orientation via epitaxial growth ona-plane sapphire substrates. Our work opens up new ways to use GaN nanowires as nanobuilding blocks.

Controlled growth of gallium nitride single-crystal nanowires using a chemical vapor deposition method

release during PIPAAm collapse. This burst is analogous to drug release from collapsing PIPAAm gel disks undergoing analogous thermal treatment. Similarly, just after each temperature return to 30 °C, small fluores-cent spikes are observed. In contrast, oscillatory fluorescent changes have been observed using 0.5 min cyclic intervals (shown in Fig. 3c) indicating subtle PIPAAm swell–shrink transition kinetics affecting flow profiles. Aqueous flow has been blocked completely using air bubbles in PIPAAm-grafted capillaries ( = 200 lm) above the PIPAAm transition temperature, where the microchannel surfaces are hydrophobic, trapping the air bubble. Our microfluidic channels distinguish their flow-control behavior by completely blocking water flow via PIPAAm graft hydration. Considerably higher pressure is required to initiate water flow through PIPAAm-grafted capillaries below PIPAAm’s collapse-transition temperature. Thermally regulated flow control in PIPAAm-grafted capillaries is rapid and reversible, facilitating many reliable and repeated open–close cycles. Such reversible, thermally modulated, polymer-grafted on–off switches for controlling microfluidic behavior might be regulated locally on-chip using optical signals (local infrared heating), resistive heating microelements, or external thermostats. Spatial control is possible using patterned grafted capillaries and different polymergrafted areas with chemistries exhibiting distinct phase-transition behavior in designated locations. Opportunities for new microvalve systems exploiting this basic design are substantial.

Synthesis and Electronic Properties of Individual Single-Walled Carbon Nanotube/Polypyrrole Composite Nanocables

This letter presents an approach to engineer the band structure of carbon nanotube field-effect transistors via selected area chemical gating By exposing the center part, or the contacts, of nanotube devices to oxidizing or reducing gases, a good control over the threshold voltage and subthreshold swing has been achieved Our experiments reveal that NO2 shifts the threshold voltage positively, while NH3 shifts it negatively for both center-exposed and contact-exposed devices However, modulations to the subthreshold swing are in opposite directions for center-exposed and contact-exposed devices: NO2 lowers the subthreshold swing of the contact-exposed devices, but increases that of the center-exposed devices In contrast, NH3 reduces the subthreshold swing of the center-exposed devices, but increases that of the contact-exposed devices

Xiaolei Liu

Papers

Chemical gating of In2O3 nanowires by organic and biomolecules

Chemical Gating of In2O3 Nanowires by Organic and Bio Molecules

Controlled growth of gallium nitride single-crystal nanowires using a chemical vapor deposition method

Synthesis and Electronic Properties of Individual Single-Walled Carbon Nanotube/Polypyrrole Composite Nanocables

Band engineering of carbon nanotube field-effect transistors via selected area chemical gating