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The adult morphology of Lestidiops extremus (Ege, 1953), a barracudina originally described based on postlarvae from Indonesia, has long been a mystery. An adult specimen collected from off the Philippines represents the first confirmed record of an adult of this species. Observations on the holotype and a detailed description of the adult are provided. The location of the pelvic-fin origin in the adult, clearly behind the posterior end of the dorsal-fin base, is unique within this genus and the entire subfamily Lestidiinae. The present find extends the known range of the species from northwestern New Guinea, Indonesia, to seas east of the Philippines.

The original description of Macroparalepis elongatus Ege, 1933 (family Paralepididae) was based on a young specimen taken from Sri Lanka. No adult information is available since it was described. Six additional specimens, including three adults and three young specimens, were found in the museum collections. The adult morphology is described for the first time and its distribution range is now extended to South Pacific Ocean off New Caledonia and Australia, and the Western Indian Ocean off Madagascar. Detailed description and comparison of these specimens and the holotype, as well as a revised diagnosis for the species, are provided.

本研究旨在以行動研究方式，運用翻轉教學模式於特殊幼兒教育課程中，以解決研究者在教學上所面臨之大學生課程參與和學習動機與成效的問題，同時，從教學實踐行動中，反思翻轉教學模式的運用，以及探討翻轉教學模式對學生課程參與和學習成果的影響。研究者運用之翻轉教學模式，包括課前預習、課中討論、課外專題和課後省思等四項策略，並以研究者於 2018 年所開設之「特殊幼兒教育」課程的 147 位修課學生為對象，透 過行動研究之動態循環歷程，從中反思和調整教學行動。此外，蒐集學生學習省思、教室觀察、小組學習單、同儕檢核和研究日誌等質性資料，並採用恆常比較法進行質性資料分析，同時，輔以研究者自編之學習回饋檢核表的量化資料分析，以瞭解教學實踐研究的結果。研究結果發現翻轉教學模式能有效因應和解決研究者在大學教學上所面臨的問題，同時，研究結果顯示，翻轉教學模式的實施成效包括：( 一 ) 促進學生在課堂中的參與意願、( 二 ) 增進學生對課程目標的學習，以及 ( 三 ) 提升學生在小組合作學習、自主學習、口語表達和反思等潛在課程的學習表現。本研究之翻轉教學模式和行動研究歷程，可提供大學教師在因應學生課堂參與問題，以及教學實踐探究之參考。 Adopting an action research approach, this study employs the flipped-teaching model in a special early childhood education course to deal with the problems faced by the researcher regarding undergraduate students’ course participation, learning motivation, and effectiveness. During the teaching practice, the study examined both the implementation of the flippedteaching model and its effects on student participation and learning outcomes.The flippedteaching model employed herein was comprised of four sections: pre-course preparation, classroom discussion, off-course seminar, and follow-up reflection. The participants were 147 students in a special early childhood education course taught by the researcher in 2018, and the teaching practice was reflected on and adjusted accordingly during the dynamic and cyclical process of action research. Qualitative data, including students’ reflections, records of classroom observations, group learning sheets, and research journals, were collected and then analyzed via the constant comparative method. In order to examine the outcome of teaching practice, quantitative data were also collected with a student feedback questionnaire developed by the researcher.The results include the following. (1) The flipped-teaching model can effectively raise students' willingness to participate in class and their motivation. (2) The flipped-teaching model can enhance student learning objectives in course acquisition. (3) The flipped-teaching model can promote students' performance on cooperative learning, self-learning, oral expression, and reflection.

By varying annealing temperature (300°C–400°C) and nitrogen content (x = 0.33, 0.56) in the WNx films, the effective work function of WNx can modulate from 4.29 to 4.91 eV. WNx is deposited on SiO2/Si stacks by reactive sputtering. The effective work function increases with increasing annealing temperature and decreases with increasing nitrogen content. The effective work function modulation is due to the dipole formation at the WNx/SiO2 interface. Oxygen diffuses from SiO2 into WNx during annealing and forms the WNxOy near the interface. The dipole with the direction from WNxOy to WNx is formed because the group electronegativity of WNxOy near the WNx/SiO2 interface is larger than that of the WNx. The WNx with high nitrogen content can alleviate the oxidation and reduce dipole formation.

Tungsten-based material is a promising candidate for work function metal. Tungsten with high electrical conductivity and midgap work function [1] has been used to fill the gate and contact plugs in the industry. In this work, the effective work function (EWF) of sputtered WN x is tuned by varying the annealing temperature and the nitrogen content in the WN x films. The EWF of sputtered WN x has 600 meV range around Si midgap. Furthermore, the tungsten-based gate metal WN x C y by plasma-enhanced atomic layer deposition (PEALD) is successfully integrated in stacked gate-all-around (GAA) transistors to modulate the Vt with no performance degradation.

The high peak mobility of 509 cm2/ $\text {V}\cdot \text {s}$ of the chemical vapor deposition -grown GeSn pMOSFETs is obtained using 1-nm Ge cap. The Ge cap on GeSn can reduce the scattering of oxide/interface charges and surface roughness for the holes in the GeSn quantum wells. However, the thick cap induces holes in the Ge cap itself, leading lower mobility than GeSn channels. The on current is enhanced by external stress due to the effective mass reduction. The normalized noise power density of the GeSn devices decreases with increasing Ge cap thickness, indicating the carrier number fluctuation and correlated mobility fluctuation are suppressed when the holes are away from interface.

Al electrode on Al2O3/GeOx/Ge dielectrics stack has smaller interface trap density than Pt electrode due to the AlGeO formation at the interface. The AlGeO interfacial layer (IL) is formed during Al deposition. Pt electrode deposition after Al capping/removal process also exhibits the low interface trap density behavior. The increasing Al electrode area decreases interface trap density, indicating the AlGeO passivation is only effective underneath Al electrode. AlGeO layer can effectively passivate Ge with scaled GeOx and Al2O3 thickness. The peak hole mobility in Ge p-MOSFETs with AlGeO IL is 277 cm2/ $\text {V}\cdot \text {s}$ .

The record low contact resistivity $(\rho_{\text{c}})$ of $4.4\text{x}10^{-10}\Omega-\text{cm}^{2}$ is achieved in Ti metal contact to in-situ B-doped $\text{GeSn}$ using B $(> 1\text{x}10^{21}\text{cm}^{-3})$ and Sn $(> 12\%)$ segregations at the Ti/GeSn:B interface. Sn incorporation into Ge lowers the Schottky barrier height of holes. Increasing B doping at the $\text{Ti}/\text{GeSn}:\text{B}$ interface reduces the hole tunneling distance. Thanks to the low growth temperature (305°C) of the chemical vapor deposition using Ge2H6, the GeSn:B with the bulk active [B] of $2.1\text{x}10^{20}\text{cm}^{-3} (>> > \text{the}$ solid solubility of B in $\text{Ge}=5.5\text{x}10^{18}\text{cm}^{-3}$ ) and the bulk [Sn] of 4.9% is successfully grown. Without the needs of the previously reported Ga dopants and the high temperature annealing for dopant activation, the record low $\rho_{\text{c}}$ is achieved with all the process temperatures $\leq 400^{\text{o}}\text{C}$ .

It is the first time that CVD-grown GeSn channels with low thermal budget of 400°C significantly outperforms the Ge channel processed at high thermal budget of 550°C. Low thermal budget is necessary to prevent the Sn loss during the process. Note that only MBE-grown GeSn had large mobility reportedly in the past. Even with high Sn content (9%), the strong photoluminescence is observed from GeSn layers on Ge buffer on 300mm Si (001), indicating the high crystalline quality by CVD epitaxy. Ge cap with significant Δ Ev at Ge/GeSn interface can ensure the gate stack quality, and reduce the scattering of holes in the GeSn quantum wells by oxide/interface charges and surface roughness. However, the mobility is degraded by thick cap due to low hole population in the GeSn wells. The ∼7% mobility enhancement on channel direction is observed using external transverse uniaxial tensile strain of ∼0.11% due to the reduction of effective mass. The mobility of GeSn QW p-MOSFETs increases with decreasing temperature at both high and low inversion carrier density, indicating that the mobility is dominated by phonon scattering. On the contrary, Ge channels are dominated by Coulomb scattering at low inversion carrier density, which has decreasing mobility with decreasing temperature. The normalized noise power density of GeSn p-MOSFETs decreases with increasing Ge cap thickness, reportedly for the first time, indicating that the carrier number fluctuation and correlated mobility fluctuation can be reduced when the carriers are away from interface.

The atomically flat surface of Bi 2 Se 3 due to the van der Waals bonded layer structure can reduce the interface trap. The metal-insulator-metal capacitors using Bi 2 Se 3 has better quadratic voltage coefficient of capacitance. This is the first time that atomically flat metal surface is used in electronic devices.

Pseudomorphic Ge 0.91 Sn 0.09 on Ge on Si with strong photoluminescence and low defect density is used for p-MOSFET channels. The mobility of Ge 0.91 Sn 0.09 Quantum Well p-MOSFETs are higher than control Ge p-MOSFETs due to hole population in the GeSn wells. The 7.5% mobility enhancement on channel direction is observed using external transverse uniaxial tensile strain (∼0.11%). The highest [Sn] of 9% in the channels grown by CVD, Pt SB S/D, high I on /I off ratio, and strain-enhanced mobility are obtained in this work.

High performance junctionless Ge Gate-all-around pFETs with fin width down to 9 nm are demonstrated. The device with the L eff of 250 nm and channel doping of 8×10 cm- has I on /I off = 1×10, SS = 95 mV/dec, and I on = 390 μA/μm. The gate controllability can be further improved with low EOT gate stack of ∼ 0.7 nm for the SS down to 84 mV/dec. Junctionless devices also show higher mobility at the large V Gs − V t region than the inversion mode devices due to less dependence on surface roughness scattering. The configuration of fin width and channel concentration to achieve low SS is investigated.

The Ge-on-insulator metal-oxide-semiconductor detector was fabricated by the wafer bonding and smart-cut. The surface roughness after smart-cut is reduced to be ~7 nm at 150ºC, due to the suppression of hydrogen outdiffusion. The large work function metal (Pt) is used for the gate electrode on the n- type Ge on insulator to reduce the dark current. Due to the small bandgap of Ge, the 850 nm, 1.3 μm and 1.55 μm infrared can be detected. The increasing photo response of the detector using the Ge-on-insulator with decreasing bonding temperature also indicates that the defects caused by hydrogen implantation are passivated more effectively by hydrogen at lower temperature. In order to increase the responsivity of 1.3 μm infrared, n-Ge thickness of 1.3 μm is used, and the responsivity reaches 231 mA/W. The external mechanical strain can further enhance the photo current without degradation of dark current.

We report that GeO2 passivation reduces surface recombination on Ge through both the reduction of interface state density and the field effect of the oxide charge. Furthermore, the photoluminescence intensity increases with increasing GeO2 thickness, mainly because of the reduction in interface state density since the fixed charge density remains almost constant. The direct-to-indirect band-gap emission ratio also remains unchanged after passivation. The p-Ge (1-3 Ω·cm) lifetime is 65 μs, as determined from the quasi-steady-state photoconductance on Ge wafers with different thicknesses. A 47-nm-thick GeO2 layer can reduce the surface recombination velocity on Ge to 70 cm/s.

Hierarchical structures combining micropyramids and nanowires with appropriate control of surface carrier recombination represent a class of architectures for radial p-n junction solar cells that synergizes the advantageous features including excellent broad-band, omnidirectional light-harvesting and efficient separation/collection of photoexcited carriers. The heterojunction solar cells fabricated with hierarchical structures exhibit the efficiency of 15.14% using cost-effective as-cut Czochralski n-type Si substrates, which is the highest reported efficiency among all n-type Si nanostructured solar cells. We also demonstrate the omnidirectional solar cell that exhibits the daily generated power enhancement of 44.2% by using hierarchical structures, as compared to conventional micropyramid control cells. The concurrent improvement in optical and electrical properties for realizing high-efficiency omnidirectional solar cells using as-cut Czochralski n-type Si substrates demonstrated here makes a hierarchical architecture concept promising for large-area and cost-effective mass production.

A two-actuator electrohydraulic bending machine is a typical MIMO system, where the level control function is degraded by the interior structural difference between the two actuators and also by the hydraulic drive interaction. The conventional self-tuning control and decoupling method are too complicated and time-consuming, and are not suitable for this system. Based upon our previous studies, this system can be simplified as two individual sets of servo-control actuating system, which is simulated as a 1st-order ARMAX model and its coupling interactions between actuators are treated as a disturbance term of the ARMAX model. Then, two sets of implicit self-tuning controller and a level control regulator are designed for servo-tracking and level control. This proposed control scheme not only reduces the number of parameter estimations significantly, but also yields the effect of dither in order to overcome the drawbacks of servovalve stickiness and mechanical frictions. Finally, the experimental results indicate its satisfactory performance and prove its superior decoupling ability and disturbance rejection.

Ge/strained GeSn/Ge quantum wells are grown on a 300 mm Si substrate by chemical vapor deposition. The direct bandgap emission from strained GeSn is observed in the photoluminescence spectra and is enhanced by Al2O3/SiO2 passivation due to the field effect. The electroluminescence of the direct bandgap emission of strained GeSn is also observed from the Ni/Al2O3/GeSn metal-insulator-semiconductor tunneling diodes. Electroluminescence is a good indicator of GeSn material quality, since defects in GeSn layers degrade the electroluminescence intensity significantly. At the accumulation bias, the holes in the Ni gate electrode tunnel to the strained n-type GeSn layer through the ultrathin Al2O3 and recombine radiatively with electrons. The emission wavelength of photoluminescence and electroluminescence can be tuned by the Sn content.

Based on the concept of iconicity, the iconicity hypothesis was emphasized for decades. The aims of this study were to explore the effect of translucency on transparency and symbol learning for children with and without cerebral palsy. Twenty children with cerebral palsy and forty typical peers participated in the study. Ten symbols with high translucency and ten with low translucency were used as experimental material. The results of transparency testing demonstrated the positive relationship between translucency and transparency. The effect of translucency on symbol learning was supported partially, all children with and without CP could learn the low translucent symbols only after two teaching sessions, or three sessions at most. The authors also provided some suggestions for further study based the results of this study.

We have performed a magnetotransport study on an AlGaN/GaN heterostructure at low temperatures. The effective-mass values have been evaluated by analyzing the exact form of the temperature-dependent Shubnikov–de Haas oscillation function. The values obtained increase with the magnetic field. This mass enhancement is attributed to conduction-band nonparabolicity. The effective-mass variation with the magnetic field was extrapolated to zero field, together with further correction due to the triangular confinement of the carriers, yielding an effective mass of 0.185±0.005 of the free-electron mass. Our result is in excellent agreement with the results obtained by first-principle calculations and the tight-binding method, and suggest the significance of magnetic-field-induced nonparabolicity in transport measurements.

The Ge/Si heterojunction MOS LED can emit ~2 mum light due to the radiative recombination at type II heterojunction. The fully depleted 800 nm germanium on insulator (GOI) can increase the responsivity and the speed of the MOS detector due to the large absorption of Ge and the electrical field in the active layer, respectively. Moreover, the external strain can tune the emission energy (~11 meV) by modifying the band structure. The responsivity of GOI MOS detector is also improved by ~10% using the external strain. Both heterojunction and strain (internal or external) can enhance the performance of Si-based optoelectronics

The hole mobility enhancement can be as high as /spl sim/18% for SiO/sub 2/ and /spl sim/20% for high-k HfO/sub 2/ gate stack dielectrics with the uniaxial compressive strain (0.2%) parallel to the channel. The highest drain current of /spl sim/22% at saturation and /spl sim/30% at linear region is observed for the bulk Si PMOS with high-k gate stacks. The drain current and hole mobility of bulk Si PMOS are degraded under the small biaxial tensile strain, while substrate-strained Si device displays the opposite. The nonoptimized ring oscillator has the speed enhancement of /spl sim/7% under the uniaxial tensile strain parallel to NMOS channel. Proper package strain also gives the drive-current as well as mobility enhancement at 100/spl deg/C.

Utilizing remote NH3/H2 plasma on GeO2/Ge can achieve the nearly-free interfacial layer and low equivalent oxide thickness of ∼0.4 nm by the formation of tetragonal ZrO2 phase. However, the electrical defects in ZrO2 result in a large C-V hysteresis (∼580 mV). The fluorine incorporation by CF4 plasma is demonstrated to effectively passivate these defects both experimentally and theoretically. The hysteresis is reduced to be ∼200 mV, and the interface defect density, permittivity, and gate leakage current remain intact. The Zr-F bond formation to remove the midgap states calculated by the density-function-theory may be the origin of passivation.

The dependence of electron mobility on strain, channel direction, and substrate orientation is theoretically studied for the germanium n-channel metal-oxide-semiconductor field-effect transistors. For the unstrained channel, (111) substrate can provide the highest mobility among the three orientations, mainly due to its largest quantization mass and smallest conductivity mass in L valley. The tensile strain parallel to the [1¯10] channel direction on (111) substrate gives 4.1 times mobility of Si at 1MV∕cm, and the mobility enhancement starts to saturate for the strain larger than 0.5%. The compressive strain of ∼1.5% transverse to [1¯10] on (111) substrate yields 2.9 times mobility enhancement at 1MV∕cm.

A single crystalline thin film of Ge on glass is fabricated using wafer bonding and smart cut. A simple metal-insulator-semiconductor detector is demonstrated for visible light and telecommunication wavelength. The implantation damage of separated Ge film bonded on glass is removed by chemical etching, and the surface roughness is reduced from 14to4nm. The defect removal reduces the dark current by a factor of 30 and increases the responsivity by a factor of 1.85 at visible wavelength. The responsivity of 0.27A∕W at 1.3μm wavelength for an unetched device does not increase after damage removal due to the decrease of the absorption layer thickness.

The current change of n-channel polycrystalline silicon thin-film transistors is analyzed experimentally and theoretically under different strain conditions. Under the uniaxial strain parallel to the channel, the +6.7% and +5.3% drain current enhancements are achieved in linear and saturation regions, respectively. There are −4.4% (linear) and −4.6% (saturation) drain current degradations when the uniaxial strain is applied perpendicular to the channel. The polycrystalline silicon is mainly composed of (111)-oriented grains, measured by electron diffraction pattern. Phonon-limited mobility is theoretically calculated. There is a qualitative agreement between experiments and theoretical analysis.

The authors apply the microwave-modulated technique to study the transport properties of two-subband-populated AlGaN∕GaN heterostructures. The microwave modulation enhances the small Shubnikov–de Haas oscillations at low magnetic fields, providing a direct way to compare the mobilities of different subbands from the experimental data. In addition, this technique can help us to determine the subband-energy separation, especially when the population of the second subband is much lower than that of the first one. Variation of subband-energy separation due to different spacer thicknesses is obtained. Therefore, the authors showed a powerful way to probe parameters of two-subband-populated AlGaN∕GaN heterostructures.