Yeong Her Wang

A Quasi-3-D Scaling Length Model for Trapezoidal FinFET and Its Application to Subthreshold Behavior Analysis

Based on the equivalent channel width and equivalent number of gates, a quasi-3-D scaling length model for the trapezoidal FinFET (TzFinFET) is developed. By accounting for the coupling effects between equivalent double-gate FET and single-gate FET, the scaling length of TzFinFET can be accurately predicted. Besides Fin height, top Fin width, and gate oxide, the scaling length is also sensitive to the inclination angle induced by the process technology. By applying this derived scaling length to the TzFinFET, the subthreshold behavior model including threshold voltage and subthreshold swing can be achieved. Both threshold voltage roll-off and subthreshold swing roll-up can be well controlled by the scaling factor in accordance with the scaling theory. According to the scaling factor, the acceptable minimum channel length that allows the maximum subthreshold degradation can be uniquely determined. The variability of subthreshold characteristics with the process parameter is also taken into account in this paper.

Highly Uniform Resistive Switching Properties of Solution‐Processed Silver‐Embedded Gelatin Thin Film

The silver-embedded gelatin (AgG) thin film produced by the solution method of metal salts dissolved in gelatin is presented. Its simple fabrication method ensures the uniform distribution of Ag dots. Memory devices based on AgG exhibit good device performance, such as the ON/OFF ratio in excess of 105 and the coefficient of variation in less of 50%. To further investigate the position of filament formation and the role of each element, current sensing atomic force microscopy (CSAFM) analysis as well as elemental line profiles across the two different conditions in the LRS and HRS are analyzed. The conductive and nonconductive regions in the current map of the CSAFM image show that the conductive filaments occur in the AgG layer around Ag dots. The migration of oxygen ions and the redox reaction of carbon are demonstrated to be the driving mechanism for the resistive switching of AgG memory devices. The results show that dissolving metal salts in gelatin is an effective way to achieve high-performance organic-electronic applications.

Barium Zirconate Nickelate as the Gate Dielectric for Low-Leakage Current Organic Transistors

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Design of compact multilayered quad-band bandpass filter

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High efficiency transparent digital television antenna based on nano-structured thin film coating technology

</tex-math></inline-formula> barium zirconate nickelate (BZN) gate dielectric layer was prepared through the low-temperature sol–gel method and was used in pentacene-based organic thin-film transistor (OTFT) applications. In comparison with its barium zirconate oxide (BZO) counterpart, experimental results show that the threshold voltage of the BZN-based OTFTs decreases from −2 to −1.1 V, the gate leakage decreases from 10⁻⁸ to 10⁻¹² A, the carrier mobility increases from 2.1 to 5.2 cm²/Vs, and the subthreshold swing decreases from 2.4 to 0.4 V/decade. The effect of Ni on device characteristics is discussed in this paper. Ni(II) acetylacetone possesses two pairs of symmetrical bidentate ligands, which can chelate with Zr ion to smoothen surface roughness. The dielectric constant can be increased. The enhancement of mobility is partly attributed to the smoother surface to reduce the scattering effects of the carrier. In addition, the improved film quality may also increase the barrier height and reduce the leakage current, which enhances the ON/ OFF ratio through the chelate effect due to the addition of Ni in BZO. Furthermore, excellent operation stability can be achieved.

Resistive switching properties of alkaline earth oxide-based memory devices

In this paper, we proposed a compact quad-band bandpass filter (BPF) using multilayer substrate technique. The filter is designed to have quad-band at 1.8, 2.4, 3.5 and 4.2 GHz. The four passbands are simultaneously generated by controlling the impedance and length ratios of the stub-loaded stepped impedance resonators (SIRs). By using the stub-loaded SIRs, the filter with closed passbands can be easily achieved. The frequency response of wide stopband is generated by using the defected ground structure (DGS) and having around −25 dB stopband from 4.2 to 12 GHz. The filter can provide the multi-path propagation to enhance the frequency response and achieving the compact circuit size. The measured results are in favorable agreement with the full-wave electromagnetic (EM) simulation results.

A Novel Localized-Trapped-Charge-Induced Threshold Voltage Model for Double-Fin Multi-Channel FETs (DFMcFETs)

In this paper, we proposed the high transparent digital television (DTV) antenna. The used transparent material is based on nano-structured thin film coating on the glass substrate for achieving the transparency up to 80%. The substrate dimension size of the proposed design is 200 × 150 mm2. The proposed antenna has radiation efficiency of 66.52% and having the bandwidth of 0.46–0.66 GHz. The proposed antenna is very much compatible to digital television signal receiving applications.

A new noise margin and average static power model for junctionless double-gate FETs (JLDGFET) working in subthreshold logic gate

A reduced high-resistance state (HRS) current assists in obtaining high ON/OFF ratio and is beneficial to operation flexibility. This study proposes that less difference in the atomic radius of alkaline earth oxide-based memory devices is beneficial to reduce the HRS current. Forming-free resistive-switching behavior in the alkaline earth oxide-based memory device using magnesium titanate (MTO), strontium titanate (STO), and barium titanate (BTO) thin films is fabricated by sol-gel method. The dependence of HRS current on the difference in atomic radius was predicted by the Hume–Rothery rule and confirmed experimentally. The hydrolyzed particles, surface roughness, and density of oxygen vacancy were decreased when the difference in atomic radius between the Ti element and alkaline earth metal was less. Compared with the BTO thin film, the MTO thin film has fewer particles, smoother surface, and less density of oxygen vacancy, resulting in lower HRS current. Thus, suitable element selection for the alkaline earth oxide-based memory devices can reduce the HRS current.

A unified quantum scaling length model for nanometer multiple-gate MOSFETs

With the effects of localized trapped charges on the flat-band voltage, a novel localized-trapped-charge-induced threshold voltage model for the double-fin multi-channel FET (DFMcFET) is presented based on the quasi-3-D scaling equation and minimum bottom-central potential. It is shown that the deep trench of the DFMcFET is superior to the shallow one in respect of reducing the localized-trapped-charge-induced threshold voltage degradation (LTTVD). Besides, the low drain voltage <inline-formula> <tex-math notation=LaTeX>

Effects of Average Power-Handling Capability on DC-Sputtering Aluminum Nitride Thin Film on Ceramic Substrate

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