The subthreshold swing (SS) of an asymmetric junctionless double gate (AJLDG) MOSFET is analyzed by the use of Gaussian function. In the asymmetric structure, the thickness of the top/bottom oxide film and the flat-band voltages of top gate (Vfbf) and bottom gate (Vfbb) could be made differently, so the change in the SS for these factors is analyzed with the projected range and standard projected deviation which are parameters for the Gaussian function. An analytical subthreshold swing model is presented from the Poisson’s equation, and it is shown that this model is in a good agreement with the numerical model. As a result, the SS changes linearly according to the geometric mean of the top and bottom oxide film thicknesses, and if the projected range is less than half of the silicon thickness, the SS decreases as the top gate oxide film is smaller. Conversely, if the projected range is bigger than a half of the silicon thickness, the SS decreases as the bottom gate oxide film is smaller. In addition, the SS decreases as Vfbb-Vfbf increases when the projected range is near the top gate, and the SS decreases as Vfbb-Vfbf decreases when the projected range is near the bottom gate. It is necessary that one should pay attention to the selection of the top/bottom oxide thickness and the gate metal in order to reduce the SS when designing an AJLDG MOSFET.

In this letter, we propose and analyze a new asymmetric structure that can be used for next-generation power semiconductor devices. We compare and analyze the electrical characteristics of the proposed device with respect to those of symmetric devices. The proposed device has a p-emitter on the right side of the cell. The peak electric field is reduced by the shielding effect caused by the p-emitter structure. Consequently, the breakdown voltage is increased. The proposed asymmetric structure has an approximately 100% higher Baliga’s figure of merit (~94.22 MW/cm²) than the symmetric structure (~46.93 MW/cm²), and the breakdown voltage of the device increases by approximately 70%.

Oxide (SiO₂)/Metal(Ag)/Oxide(SiO₂, ITO, ZnO) multilayer films were fabricated using a magnetron sputtering technique at room temperature on Si (p-type, 100) and a glass substrate. The electrical and optical properties of the asymmetric multilayer films depended on the thickness of the mid-layer film and the type of oxide in the bottom layer. As the metal layer becomes thicker, the sheet resistance decreases. However, the transmittance decreases when the metal layer exceeds a threshold thickness of approximately 10~12 nm. In addition, the sheet resistance and transmittance change according to the type of oxide in the bottom layer. If the oxide has a large resistivity, the overall sheet resistance increases. In addition, the anti-reflection effect changes according to the refractive index of the oxide material. The optical and electrical properties of multilayer films were investigated using an ultraviolet visible (UV-Vis) spectrophotometer and a 4-point probe, respectively. The optimum structure is SiO₂ (30 nm)/Ag (10 nm)/ZnO (30 nm) multilayer, with the highest FOM value of 7.7×10^-3 Ω^-1.

The floodlighting assists the pilot in taxiing the aircraft into and out of the final parking position and provide lighting suitable for passenger to embark and debark and for personnel to load and unload cargo. It is composed of sodium lamps which is consuming high energy. It needs to develop a dedicated LED lamp to replace the existing lamps. In this paper, We propose a suitable asymmetric angle of LED lamps to avoid a pilot’s glare and to meet the standard illumination. For this, we analyze asymmetric angle of sodium lamps which are using in airport and confirm whether the illumination distribution and glare index meet the relating standards by using simulation method. Also, we study the needs of asymmetric characteristics of LED ramp by simulating the LED lamps with and without asymmetric characteristics of ramp respectively. With the simulation result, finally we propose the best asymmetric angle of LED lamp to meet the average illumination standard, and avoid a pilot``s glare.