Field effect

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

Effect of large work function modulation of MoS2 by controllable chlorine doping using a remote plasma

Abstract: Adjusting the intrinsic properties of 2-dimensional (2D) transition metal dichalcogenide materials is important for their various applications in electronic devices. Among them, molybdenum disulfide (MoS2) is one of the most attractive layered 2D materials because of its excellent electrical properties as well as good thermal and oxidation stability. Controlling the doping process and analyzing how the dopant atoms affect the device properties are crucial for advanced applications of TMDs. In this study, a simple and controllable chlorine doping method of MoS2 using a remote inductively coupled plasma (ICP) was studied and the effect of doping on the properties of MoS2 was investigated by adjusting the work function of MoS2. Kelvin probe force microscopy (KPFM) shows a gradual decrease of the work function with increasing chlorine radical treatment time. Chlorine doped MoS2 field effect transistors (FETs) exhibited improved electrical characteristics such as the field effect mobility and on current level as demonstrated by the transfer characteristics (Id–Vgs). Especially, the chlorine doped MoS2 FETs showed increased photoresponsivity by 1.94 times (from 424 to 824 A W−1) for green light (λ = 520 nm) and, much more interestingly, 8.59 times (from 37.6 to 323 A W−1) for near-infrared (NIR) light (λ = 785 nm).

Electric field effect on the artificial grain boundary of bicrystal YBa2Cu3O7−δ films

Abstract: An ability of the artificial grain boundary of bicrystal YBa2Cu3O7−δ thin films is demonstrated as the field effect channel of high Tc field effect devices. The influence of field application on the channel resistance is examined with a metal‐insulator‐semiconductor‐type structure, in which a channel is arranged across the grain boundary. The field‐induced change in the resistance of the grain boundary is enhanced up to around 5% by lowering temperature below Tc of adjoining YBa2Cu3O7−δ grains. The enhancement is explained not only by an increase in the dielectric constant of the gate insulator (SrTiO3) but also by a reduction in the carrier density nearby the grain boundary. The latter is indeed a benefit to high Tc field effect devices.An ability of the artificial grain boundary of bicrystal YBa2Cu3O7−δ thin films is demonstrated as the field effect channel of high Tc field effect devices. The influence of field application on the channel resistance is examined with a metal‐insulator‐semiconductor‐type structure, in which a channel is arranged across the grain boundary. The field‐induced change in the resistance of the grain boundary is enhanced up to around 5% by lowering temperature below Tc of adjoining YBa2Cu3O7−δ grains. The enhancement is explained not only by an increase in the dielectric constant of the gate insulator (SrTiO3) but also by a reduction in the carrier density nearby the grain boundary. The latter is indeed a benefit to high Tc field effect devices.

Electrical properties of pseudo-single-crystalline Ge films grown by Au-induced layer exchange crystallization at 250 °C

Abstract: We study the electrical properties of pseudo-single-crystalline Ge (PSC-Ge) films grown by a Au-induced layer exchange crystallization method at 250 °C. By inserting the SiNx layer between PSC-Ge and SiO2, we initiatively suppress the influence of the Ge/SiO2 interfacial defective layers, which have been reported in our previous works, on the electrical properties of the PSC-Ge layers. As a result, we can detect the influence of the ionized Au+ donors on the temperature-dependent hole concentration and Hall mobility. To further examine their electrical properties in detail, we also fabricate p-thin-film transistors (TFTs) with the PSC-Ge layer. Although the off-state leakage currents are suppressed by inserting the SiNx layer, the value of on/off ratio remains poor (<102). Even after the post-annealing at 400 °C for the TFTs, the on/off ratio is still poor (∼102) because of the gate-induced drain leakage current although a nominal field effect mobility is enhanced up to ∼25 cm2/V s. Considering these features, we conclude that the Au contaminations into the PSC-Ge layer can affect the electrical properties and device performances despite a low-growth temperature of 250 °C. To achieve further high-performance p-TFTs, we have to suppress the Au contaminations into PSC-Ge during the Au-induced crystallization growth.

An improved differential comparator with field effect diode output stage

Abstract: In a field effect diode, carriers of a p–n junction can be modulated on-line. The p and n regions are created by two oppositely biased, and closely spaced, gates in CMOS SOI technology. Using gates as the third terminal, the field effect diode can operate as a switch or as an amplifying element. In this paper, a conventional differential comparator is designed and its performance is compared with a circuit which uses field effect diodes in its output stage. It is shown that the large current sinking and supplying capability of the field effect diode causes this comparator to operate faster than the conventional circuit, consumes less power and covers less chip area.