Field effect

About: Field effect is a research topic. Over the lifetime, 4018 publications have been published within this topic receiving 92613 citations.

Method for manufacturing ion implanted insulated gate field effect semiconductor transistor devices

Abstract: A method for manufacturing insulated gate field effect transistor devices utilizing ion implantation for elimination and suppression of mobile ion contamination is described and comprises bombarding and implanting hydrogen or helium into the dielectric insulating layer of an insulated gate field effect transistor at relatively low ion energy, followed by a comparatively low temperature anneal.

Band-structure modulation in carbon nanotube T junctions.

Abstract: We show that the band structure of metallic carbon nanotubes can be dramatically altered by the local electrostatic field. This is realized by coupling chemically functionalized nanotubes to form T junctions. The bar of the T is the conducting channel and the leg of the T is used for local gating. Transport measurements reveal that an energy gap develops upon application of a local electric field in both devices with or without linker molecules at the junction. We propose that the mechanism of the band gap modulation in the T junctions without linker molecules is the field effect, with the linker molecules introducing additional electromechanical and chemical effects.

Microcrystalline silicon with high electron field-effect mobility deposited at 230°C

Abstract: We made top-gate n-channel thin-film transistors of directly deposited microcrystalline silicon (μc-Si). The μc-Si films were grown by plasma-enhanced chemical vapor deposition (PECVD) at 230°C, from a gas mixture of SiH4 and SiH2Cl2 under H2 dilution. Deposition rates of ⩾1 A/s were obtained with a plasma excitation frequency of 80 MHz. The 1.2 μm-thick films are microcrystalline with grains oriented along the [2 2 0] direction perpendicular to the glass substrates. A conductivity of 4 × 10−5 (Ω cm)−1 (300 K) and thermal activation energy of 0.25 eV are obtained for films with a concentration of bonded hydrogen of 4 at.%, and optical gap E04 (E03) of 2.0 (1.53) eV. Top-gate transistors were fabricated with the highest process temperature being 280°C. We obtained devices (W/L=180 μm/45 μm) with ON current ∼100 μA, ON/OFF current ratio of 104, and electron mobilities in the linear and saturated regimes 13 and 20 (±1) cm2/V s, respectively.

Improving the Performance of Organic Field Effect Transistor by Optimizing the Gate Insulator Surface

Abstract: The effect of oxygen plasma treatment and/or silanization with hexamethyldisilazane (HMDS) on the surface chemistry and the morphology of the SiO2-gate insulator were studied with respect to the performance of organic field effect transistors. Using X-ray photoelectron spectroscopy (XPS), it is shown that silanization leads to the growth of a polysiloxane interfacial layer and that longer silanization times increase the thickness of this layer. Most important, silanization reduces the signal from surface contaminations such as oxidized hydrocarbon molecules. In fact, the lowest concentration of these contaminations was found after a combined oxygen plasma/silanization treatment. The results of these investigations were correlated with the characteristic device parameters of polymer field effect transistors with poly(3-hexylthiophene)s as the semiconducting layer. We found that the field effect mobility correlates with the concentration of contaminations as measured by XPS. We, finally, demonstrate that silanization significantly improves the operational stability of the device in air compared to the untreated devices.

Touch switches and practical applications therefor

Abstract: A touch switch apparatus emulating a mechanical switch includes a field effect sensor and an electric field stimulator mechanically associated with the field effect sensor. A field generation signal applied to the field effect sensor causes an electric field to be generated thereabout. The electric field stimulator can be moved between first and second positions with respect to the field effect sensor. When moved into proximity with the field effect sensor, the electric field stimulator disturbs the electric field. A detection circuit coupled to the field effect sensor detects and responds to the disturbance to the electric field.