Insulator (electricity)

About: Insulator (electricity) is a research topic. Over the lifetime, 15941 publications have been published within this topic receiving 108950 citations. The topic is also known as: electrical insulator.

Low-voltage polyelectrolyte-gated polymer field-effect transistors gravure printed at high speed on flexible plastic substrates

Abstract: This study reports the fabrication of polymer field-effect transistors operating under a bias of |1 V| in which the insulator and semiconductor are gravure-printed on plastic at the high speed of 0.7 m s−1. Remarkably, the process does not necessitate any surface modification and relies solely on the careful selection and optimization of formulations based on solvent blends. In addition to demonstrating high-throughput fabrication, this study fulfills another requirement for organic electronics and achieves low-voltage operation in ambient air by using a polyelectrolyte insulator, poly(4-styrenesulfonic acid) (PSSH). PSSH is a proton conductor that forms electrical double layers at the interfaces with the gate electrode and the semiconductor channel upon application of a small gate voltage (≤ |1 V|). Printed PSSH exhibits a high capacitance of 10 µF cm−2, leading to a printed poly(3-hexylthiophene) hole mobility above 0.1 cm2 V−1 s−1 in a bottom-gate, top-contact configuration.

Electron Emission Properties of Insulator Materials Pertinent to the International Space Station

Abstract: We present the results of our measurements of the electron emission properties of selected insulating and conducting materials used on the International Space Station (ISS) Utah State University (USU) has performed measurements of the electron-, ion-, and photon-induced electron emission properties of conductors for a few years, and has recently extended our capabilities to measure electron yields of insulators, allowing us to significantly expand current spacecraft material charging databases These ISS materials data are used here to illustrate our various insulator measurement techniques that include: i) Studies of electron-induced secondary and backscattered electron yield curves using pulsed, low current electron beams to minimize deleterious affects of insulator charging ii) Comparison of several methods used to determine the insulator 1st and 2nd crossover energies These incident electron energies induce unity total yield at the transition between yields greater than and less than one with either negative or positive charging, respectively The crossover energies are very important in determining both the polarity and magnitude of spacecraft surface potentials iii) Evolution of electron emission energy spectra as a function of insulator charging used to determine the surface potential of insulators iv) Surface potential evolution as a function of pulsed-electron fluence to determine how quickly insulators charge, and how this can affect subsequent electron yields v) Critical incident electron energies resulting in electrical breakdown of insulator materials and the effect of breakdown on subsequent emission, charging and conduction vi) Charge-neutralization techniques such as low-energy electron flooding and UV light irradiation to dissipate both positive and negative surface potentials during yield measurements Specific ISS materials being tested at USU include chromic and sulfuric anodized aluminum, RTV-silicone solar array adhesives, solar cell cover glasses, Kapton, and gold Further details of the USU testing facilities, the instrumentation used for insulator measurements, and the NASA/SEE Charge Collector materials database are provided in other Spacecraft Charging Conference presentations (Dennison, 2003b) The work presented was supported in part by the NASA Space Environments and Effects (SEE) Program, the Boeing Corporation, and a NASA Graduate Fellowship Samples were supplied by Boeing, the Environmental Effects Group at Marshall Space Flight Center, and Sheldahl, Inc

Reduction of the concentration of slow insulator states in SiO2/InP metal–insulator semiconductor structures

Abstract: Spatially distributed states within the insulator are thought to be the origin of the well‐known drift phenomena usually found in InP metal–insulator semiconductor (MIS) devices. This paper will show that the concentration of these states can be reduced drastically by applying a suitable deposition technique. Plasma‐enhanced chemical vapor deposited SiO2 is used as the insulator in a process involving low substrate temperatures (200 °C), spatial separation of sample and plasma (indirect plasma method), and the addition of phosphorus into the reaction chamber during the initial stage of insulator deposition. The influence of several process parameters on the properties of the silicon dioxide films as well as the SiO2/InP interface characteristics are investigated. Deep level transient spectroscopy and C(V) measurements of InP MIS capacitors yield concentrations of slow insulator states of only 1–2×1011 cm−1 eV−1 for the best of our samples.

Direct measurement of electric field at line conductors during a.c. corona

Abstract: An electrostatic-fluxmeter probe has been used to obtain a direct measurement of the electric field at a cylindrical conductor during a.c. corona. For conductor diameters of 1.59, 2 and 2.75 cm, the resultant electric field falls below the onset level for both positive and negative corona. For the positive discharge, the field becomes independent of the applied voltage, a maximum fall of 9%, being observed. In contrast, the average field in the negative corona discharge decreases with increasing applied voltage, the effective field being reduced by up to 15% of the onset value. The assumption in many theoretical analyses of the discharge that the surface field remains at the onset value is thus invalid. It is suggested that increased secondary ionisation processes account for the maintenance of corona at reduced field strength. The measurements also fail to support the hypothesis that field enhancement occurs during positive corona owing to a negative-ion sheath. Field enhancement is observed to occur in a.c. corona prior to onset, because of remnant space charge from the preceding half cycle, but the effect is small. The field immediately following negative corona extinction is reduced, but, after positive corona, is enhanced because of electron attachment near the anode surface. The method, suitably modified, would appear to offer a useful means of study of bundle-conductor corona and precipitator assemblies of parallel line conductors.

Some electrical properties of thin film copper–borosilicate glass–copper sandwiches intended for use as electron emitters

Abstract: The electrical properties of thin film structures consisting of metal-insulator-meta sandwiches are investigated. Results for current-voltage characteristics, forming effects, temperature dependence of conductance, and the emission of electrons into n vacuum are described, particularly for the structure Cu-SiOsB2O3-Cu. Very high emission current densities are achieved for low applied voltages and with the cathode at or near room temperature. High values of hot electron attenuation length in both the copper electrode and in the insulator are obtained and the significance) of those high values is discussed.