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In-rich InAlN is a promising nitride semiconductor alloy for high-efficiency solar cells and wide-range light-emitting diodes due to its tunable bandgap from 0.7 to 6.2 eV. However, incomplete characterization has led to inconsistent fundamental properties in some studies. The aim of this study was to comprehensively investigate the structural, optical, and electrical properties of In-rich InAlN films grown on GaN/Al2O3 templates by RF-MOMBE at various temperatures. The methodology involved state-of-the-art metrology techniques, such as high-resolution x-ray diffraction (HRXRD), scanning electron microscopy (FE-SEM), Hall effect measurements, and transmission electron microscopy (TEM). The results showed that all InxAl1-xN films were epitaxially grown on the GaN/Al2O3 template, with the indium composition (x) decreasing with increasing growth temperature. Furthermore, phase separation of the In-rich InAlN films occurred at high growth temperatures(>550 °C), resulting in a relatively smooth surface. The optical absorption method measured the band-gap of the InxAl1-xN films, which ranged from 1.7 to 1.9 eV for x values between 0.77 and 0.91. The mobility and carrier concentrations of all In-rich InAlN films were measured at ∼60−277 cm2 V−1-s−1 and 2–7 × 1019 cm3 in the growth temperature of range 450 °C–610 °C, respectively. In conclusion, our comprehensive characterization using advanced metrology methods provides valuable insights into the properties of In-rich InAlN films, which can inform future optimization of these materials for various applications.

Epitaxial InN films were grown on AlN/TMAl seed layer/Si(111) substrates in the range of temperature between 500 and 540 o C using pulsed-mode RF-MOMBE. The structural properties of the InN films were characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy, and transmission electron microscopy (TEM). The electrical properties were characterized by Hall effect measurements. The results indicated that small changes in temperature significantly affect the quality of InN films. The XRD and TEM results indicated that the InN films grew oriented along the c -axis. Phi-scan XRD patterns indicated that the InN films grew epitaxially on the Si(111) substrates with the orientation relationship InN [10] , [11] InN // [220] Si . When the substrate temperature at 530°C, the TEM images indicated three-dimensional InN/AlN growth and growth rate was approximately 0.2 μm/h. The cross-sectional TEM images and SAD pattern showed a sharp InN/AlN interface and clear epitaxial orientation relationships of InN (-2110) InN //(-2110) AlN //(2-20) Si , [0001] InN //[0001] AlN //[111] Si . The electron concentrations of the InN films were measured from 5.5 × 10 19 to 1.3 × 10 20 cm −3 , and the mobility was measured from 116 to 360 cm 2 /V·s. The results indicate that controlling the substrate temperature is essential for engineering the growth of InN films on silicon wafers.

In this study, a precise optomechanical mirascope was designed using 3D printing. The mirascope comprised multiple optical mirrors and mechanical elements, which were designed and printed using the same material. This combined design reduces the errors from assembled integration and various environments. Using 3D printing to fabricate optical systems reduces cost and time compared with the traditional optical manufacturing process. Moreover, 3D printing allows more freedom in optomechanical design than traditional mechanical manufacturing allows. However, the surface finishing quality of 3D-printed components does not currently meet the requirement of precise optics. Diamond turning to finish the surface enables it to conform to the requirements of optical application. In this study, the mirascope comprised two aspherical mirrors and integrated mechanical parts with a diameter of 50.8 mm. The optical image was designed with a magnification of 0.875 × and floating distance of 1.5 mm. The mirascope was printed on an Objet500 Connex 3D printer and VeroPureWhite RGD837 and VeroBlackPlus RGD875 materials. The profile and roughness of the aspherical surfaces in printing, turning, and polishing processes were analyzed in this study. The techniques developed in this study can be applied to 3D-printed optics, mirascope, virtual reality, and 3D projection systems.

Diffraction gratings are becoming increasingly widespread in optical applications, notably in lasers. This study presents the work on the characterization and evaluation of Multilayer Dielectric Diffraction Gratings (MDG) based on the finite element method using Comsol MultiPhysics software. The optimal multilayer dielectric diffraction grating structure using a rectangular three-layer structure consisting of an aluminum oxide Al2O3 layer sandwiched between two silicon dioxide SiO2 layers on a multilayer dielectric mirror is simulated. Results show that this MDG for non-polarized lasers at 1064 nm with a significantly enhanced −1st diffraction efficiency of 97.4%, reaching 98.3% for transverse-electric (TE) polarization and 96.3% for transverse-magnetic (TM) polarization. This design is also preferable in terms of the laser damage threshold (LDT) because most of the maximum electric field is spread across the high LDT material SiO2 for TE polarization and scattered outside the grating for TM polarization. This function allows the system to perform better and be more stable than normal diffraction grating under a high-intensity laser.

Love of beauty is human’s nature. The term anti-ageing has undoubtedly become the main stream of healthcare in the twenty-first century. However, the ultimate pursuit of medical cosmetology service...

We propose a see-through display with a wavefront coding (WFC) technique using a cubic phase plate to extend the depth of field (DOF) of the projected virtual image. The image projected by the WFC see-through display allows the eyes to see an object in the range of accommodation and a clear projected image simultaneously without re-focusing. The DOF of the clear projected image by the system can be extended from 250 mm to an optical infinity of 10 m.

Indium nitride (InN) films were deposited on Al 2 O 3 substrates with a zinc oxide (ZnO) interlayer using by radio-frequency metalorganic molecular beam epitaxy (RF-MOMBE). We evaluated the impact of the flow rate of trimethylindium (In(CH 3 ) 3 , TMIn) on the structure, surface morphology, and optical and electrical properties of the films using X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–Vis spectroscopy, and Hall measurements. The XRD results indicated that all InN films were formed from single-phase wurtzite crystals with the preferred orientations along the c -axis. The SEM images indicated that the rough surfaces of the InN films grown with TMIn flow rates less than 0.55 sccm. The TEM images showed that InN and ZnO had hexagonal structures (wurtzite) that were epitaxially grown by RF-MOMBE on the substrates. The electron concentrations ranged from 7.3 × 10 19 to 2.56 × 10 20 cm −3 of the InN films were measured.

Optical metrology is a critical and complicated technique for the fabrication of precision optics which surface figure is better than RMS 1/30λ. The intrinsic systematic error of the experimental setup including the alignment error of the metrology tool and manufacturing error of the reference optics shall be calibrated carefully. Nevertheless, the measured consequence also includes the surface deformation caused by mounting supporter and gravity effect, which may result in a misleading judgment for surface figure correction, especially for mid- to-large optics. Besides the systematic error of experimental setup and deformation by an external condition of the optics, the environmental condition such as temperature drift, air turbulence, and vibration also affect the measured result. This paper proposes a method which adopts the magnitude and phase of each non-rotationally symmetrical Zernike coefficients grabbed from the multiple measurements from rotating the optics to analyze the absolute low-spatial frequency figures.

The degree of passivation of the grinding wheel is gradually increased during the machining process, the friction between the grinding wheel and the workpiece is increased which causing the vibration and noise of the machine are changed. Therefore, the vibration and noise values could be obtained by using the vibration sensor and microphone. We use the spectrum analyzer to analyze the trend of the variation of vibration and noise signals. As the wear of the grinding wheel increases, the sound acoustic pressure in the range of 4.3 kHz to 5.3 kHz decreases. As the friction between the grinding wheel and the workpiece increases, high-frequency noise greater than 6 kHz are excited and the acoustic pressure increases. According to the experimental results, it is known that the wear state of the grinding wheel and the noise spectrum in generating process has a significant correlation. The cutting force of the grinding wheel can be observed by the noise spectrum of the spectrum analyzer to identify whether there is an abnormality in the processing process to optimize the grinding parameter immediately for avoiding the damage of the lens.

Si 3 N 4 ultra-thin film were grown on nitridation of Si(111) surface by RF-N 2 plasma exposure. We discussed the effect of nitridation time, N2 flow rate and RF power on the optical, chemical, structural properties of Si 3 N 4 ultra-thin film. The surface and interface chemical composition and surface morphology are investigated by using transmission electron microscope (TEM), ellipsometer, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). TEM image shows that RF power of 350 W induced the some damage of Si(111) surface. Also, the thickness of Si 3 N 4 is approximately 5 nm. The binding energy of Si $2\mathrm{p}_{3/2}$ located at $101.9 \pm 0.1\ \mathrm{eV}$ are attributed to the Si-N bonds in a Si 3 N 4 compound. Smooth Si 3 N 4 ultra-thin film was obtained at nitridation time nearly to 1hr with RF power of 300 W, which was measured the refractive index (n) nearly to 1.88 at 632 nm. The increase in refractive index with decrease RF plasma exposure time is probably attributed to the chang in stoichiometric of film and surface damage.

One of the methods used to obtain notch filters involves one or several gradient index layers. In this method, the indices are decreased and then increased step by step to create a sinusoidal-like gradient layer. This paper reports a sinusoidal-like gradient layer fabrication method based on solid state diffusion. Al2O3/MgO/Al2O3 (AMA) was deposited by electron beam evaporation and then post-annealed at 800 &deg, C for 4 h. Through inner diffusion, the MgO layers became a low refractive index material with a porous structure (the average refractive index was 1.55) such that the MgAl2O4 spinel was formed as an inhomogeneous layer with an average refractive index of 1.69. This allowed simply using a structured multilayer, (Al2O3/MgO)8 Al2O3, and post-annealing to form a sinusoidal-like gradient layer for a UV notch filter.

Ultra-thin Si3N4 films were grown on Si(111) surface by radio frequency (RF)-N2 plasma exposure at 900 °C with 1–1.2 sccm of a flux of atomic nitrogen. We discuss the effect of various conditions such as N2 flow rate, nitriding time and RF power on the optical, chemical, and structural properties of a nitrided Si3N4 layer. The optical properties, surface morphology and chemical composition are investigated by using ellipsometry, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Cross-sectional TEM images show that an RF power of 350 W induced some damage to the Si(111) surface. The thickness of nitrided Si3N4 was measured to be about 5–7 nm. XPS results shown that the binding energy of Si 2p3/2 located at 101.9 ± 0.1 eV is attributed to the Si–N bonds in the Si3N4 compound. Smooth Si3N4 ultra-thin films were obtained at a nitridation time close to 1 h with an RF power of 300 W, with a measured refractive index (n) nearly to 1.88 at 632 nm. The increase in refractive index with decreased RF-plasma power and nitrogen flow rate is probably attributed to the change in the stoichiometry of the film and less surface damage.

The relationship between the oxygen pressure, porosity, adhesion, and ion beam-assisted deposition (IAD) conditions for WO 3 electrochromic films prepared using an electron-beam (E-beam) system was investigated. The adhesion of thin films on the substrate by sole E-beam system is very weak. The best method is proposed to obtain good adhesion and better porosity by combining the E-beam evaporation, and the microstructure and coloration efficiency were determined using a field emission scanning electron microscope (SEM) and a spectrometer, respectively. Notably, the effect of the oxygen pressure on the coloration efficiency and porosity of Ta 2 O 5 /WO 3 films was found to be different. The optimal average transmittance of the electrochromic film in the bleached state was 11%, and in the colored state was 68%, when a Ta 2 O 5 thin film was deposited in oxygen at a pressure at 9 × 10 -4 torr using IAD, and a WO 3 thin film was deposited at an oxygen pressure of 7.5 × 10 -5 torr. The studied results are useful for the design of more efficient photoelectrochemical devices employing evaporated WO 3 films.

This study describes the design and fabrication of transparent atom chips for atomic physics experiments. A fabrication process was developed to define the wire patterns on a transparent glass substrate to create the desired magnetic field for atom trapping experiments. An area on the chip was reserved for the optical access, so that the laser light can penetrate directly through the glass substrate for the laser cooling process. Furthermore, since the thermal conductivity of the glass substrate is poorer than other common materials for atom chip substrate, for example silicon, silicon carbide, aluminum nitride. Thus, heat dissipation copper blocks are designed on the front and back of the glass substrate to improve the electrical current conduction. The testing results showed that a maximum burnout current of 2 A was measured from the wire pattern (with a width of 100 μm and a height of 20 μm) without any heat dissipation design and it can increase to 2.5 A with a heat dissipation design on the front side of the atom chips. Therefore, heat dissipation copper blocks were designed and fabricated on the back of the glass substrate just under the wire patterns which increases the maximum burnout current to 4.5 A. Moreover, a maximum burnout current of 6 A was achieved when the entire backside glass substrate was recessed and a thicker copper block was electroplated, which meets most requirements of atomic physics experiments.

Mass screening with abdominal ultrasonography (AUS) has been suggested as a tool to control adult hepatocellular carcinoma (HCC) in individuals, but its efficacy in reducing HCC mortality has never been demonstrated. This study aimed to assess the effectiveness of reducing HCC mortality by mass AUS screening for HCC based on a program designed and implemented in the Changhua Community-based Integrated Screening (CHCIS) program with an efficient invitation scheme guided by the risk score. We invited 11,114 (27.0%) of 41,219 eligible Taiwanese subjects between 45 and 69 years of age who resided in an HCC high-incidence area to attend a risk score-guided mass AUS screening between 2008 and 2010. The efficacy of reducing HCC mortality was estimated. Of the 8,962 AUS screening attendees (with an 80.6% attendance rate), a total of 16 confirmed HCC cases were identified through community-based ultrasonography screening. Among the 16 screen-detected HCC cases, only two died from HCC, indicating a favorable survival. The cumulative mortality due to HCC (per 100,000) was considerably lower in the invited AUS group (17.26) compared with the uninvited AUS group (42.87) and the historical control group (47.51), yielding age- and gender-adjusted relative mortality rates of 0.69 (95% confidence interval [CI]: 0.56-0.84) and 0.63 (95% CI: 0.52-0.77), respectively. Conclusion: The residents invited to community-based AUS screening for HCC, compared with those who were not invited, showed a reduction in HCC mortality by ∼31% among subjects aged 45-69 years who had not been included in the nationwide vaccination program against hepatitis B virus infection. (Hepatology 2014;59:1840–1849)

Zirconium diboride (ZrB2) thin films were deposited on a Si(100) substrate using pulsed direct current (dc) magnetron sputtering and then annealed in high vacuum. In addition, we discussed the effects of the vacuum annealing temperature in the range of 750 to 870 &deg, C with flowing N2 on the physical properties of ZrB2 films. The structural properties of ZrB2 films were investigated with X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The XRD patterns indicated that the ZrB2 films annealed at various temperatures exhibited a highly preferred orientation along the [0001] direction and that the residual stress could be relaxed by increasing the annealing temperature at 870 &deg, C in a vacuum. The surface morphology was smooth, and the surface roughness slightly decreased with increasing annealing temperature. Cross-sectional TEM images of the ZrB2/Si(100) film annealed at 870 &deg, C reveals the films were highly oriented in the direction of the c-axis of the Si substrate and the film structure was nearly stoichiometric in composition. The XPS results show the film surfaces slightly contain oxygen, which corresponds to the binding energy of Zr&ndash, O. Therefore, the obtained ZrB2 film seems to be quite suitable as a buffer layer for III-nitride growth.

Optical interference coatings designed for use in a space-grade multispectral assembly in a complementary metal-oxide‐semiconductor sensor were deposited on glass by ion-beam-assisted deposition for a Cassegrain-type space-based remote-sensing platform. The patterned multispectral assembly containing blue, green, red, near infrared, and panchromatic multilayer high/low alternated dielectric band-pass filter arrays in a single chip was fabricated by a mechanical mask and the photolithography process. The corresponding properties of the films were investigated by in situ optical monitoring and spectrometry. It was found that the optical properties were significantly improved by employing ion-beam-assisted deposition. The average transmittances were above 88% for the multispectral assembly, with a rejection transmittance of less than 1% in the spectral range 350–1100 nm. To estimate the optical stability of optical coatings for aerospace applications, a space environment assuming a satellite orbiting the Earth at an altitude of near 800 km was simulated by a Co60 gamma (γ) radiation test.

Indium nitride (InN) films were deposited on Al 2 O 3 substrates with a zinc oxide (ZnO) interlayer using by radio-frequency metalorganic molecular beam epitaxy (RF-MOMBE). We evaluated the impact of the flow rate of trimethylindium (In(CH 3 ) 3 , TMIn) on the structure, surface morphology, and optical and electrical properties of the films using X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–Vis spectroscopy, and Hall measurements. The XRD results indicated that all InN films were formed from single-phase wurtzite crystals with the preferred orientations along the c -axis. The SEM images indicated that the rough surfaces of the InN films grown with TMIn flow rates less than 0.55 sccm. The TEM images showed that InN and ZnO had hexagonal structures (wurtzite) that were epitaxially grown by RF-MOMBE on the substrates. The electron concentrations ranged from 7.3 × 10 19 to 2.56 × 10 20 cm −3 of the InN films were measured.

This paper investigates terahertz (THz) wave propagation, resonance, and radiation on a THz optoelectronic integrated circuit (THz-OEIC). An efficient THz resonant radiation from 0.6 to 0.7 THz can be achieved with a newly designed 2-D open-ended rampart slot array antenna. A monolithically integrated circuit is fabricated on a localized THz resonant cavity, which not only provides a robust base for postdevice processes but also helps collect and reradiate the fleeing surface waves to enhance radiation efficiency. When using a THz time-domain spectroscopy (THz-TDS) technique and a time-frequency analysis, the radiated THz waveform shows a good time-frequency correlation to the circuit design of our THz-OEIC. In addition, an optical-to-THz per-pulse conversion efficiency of 6.41 × 10-3 can be achieved by a localized THz resonant cavity design. The enhanced optical-to-THz per-pulse conversion efficiency and THz propagation, resonance, and radiation behavior revealed not only help to understand the on-chip THz transmission phenomena but provide a good potentiality for a THz-OEIC design to be applied in low power-consuming microfluidic-channel-based THz biosensing chips as well.

The principle of field synergy is to simulate the comfortableness of room in this study. The parameters U, V, W and input position of wind are calculated to simulate comfortableness of room. Temperature and velocity fields are simulated by COMSOL Multiphysics software. Comfortable degree is calculated by field synergy mean square root method in this research. The simulation result shows that field synergy angle decreases while comfortable degree increases. It is very obvious that the right input position of wind leads lower field synergy angle.

Optical thin films designed for multispectral band-pass filters and a primary Ag mirror were deposited on radiation-resistant glass by ion-beam-assisted deposition. The filters and mirror are for use in the optical payload of a remote sensing instrument. The optical parameters of the films and mirror were optimized by using admittance loci analysis. The simulation shows that the band-pass filters can achieve average transmittances of 95% in the blue (B1), green (B2), red (B3), near-infrared (B4), and panchromatic (400–900 nm) spectral ranges and an average reflectance of 99% for the primary Ag mirror in the visible spectrum. The corresponding properties of the films were investigated by in situ optical monitoring, spectrometry, and high-resolution transmission electron microscopy. It was found that the average transmittances are above 85% for all five band-pass filters, with a rejection transmittance below 1% in the spectral range of 350–1100 nm. The average reflectance of the primary Ag mirror (with a pr...

The fabrication of 2-D periodic arrays of nickel metal dots using polystyrene (PS) nanosphere lithography and the interfacial reactions of the Ni dot arrays on (0 0 1) Si substrates after different heat treatments have been investigated. The epitaxial NiSi2 was detected to start growing in samples after annealing at 300 °C. As the annealing temperature was increased to 350–800 °C, only epitaxial NiSi2 nanodot arrays were observed to form. The results revealed that the formation of epitaxial NiSi2 is more favorable for the Ni metal dot arrays samples. The shape of the epitaxial NiSi2 nanodot was found to be inverse pyramidal and the size of the silicide nanodots was measured to diminish with annealing temperature. Furthermore, amorphous SiOx nanowire arrays and single-crystalline Si nanowires were found to form in samples after annealing at 900 and 1100 °C, respectively. The results present the exciting prospect that other nanoscale metal silicide dot and nanowire arrays could be grown on the sub-100 nm pre-patterned Si substrates using the PS nanosphere lithography technique.

Two-dimensional (2D) periodic arrays of Co metal and Co silicide nanodots were successfully fabricated on (0 0 1)Si substrate by using the polystyrene (PS) nanosphere lithography (NSL) technique and thermal annealing. The epitaxial CoSi 2 was found to start growing in samples after annealing at 500 °C. The sizes of the Co silicide nanodots were observed to shrink with annealing temperature. From the analysis of the selected-area electron diffraction (SAED) patterns, the crystallographic relationship between the epitaxial CoSi 2 nanodots and (0 0 1)Si substrates was identified to be [0 0 1]CoSi 2 //[0 0 1]Si and (2 0 0)CoSi 2 //(4 0 0)Si. By combining the planview and cross-sectional TEM examination, the epitaxial CoSi 2 nanodots formed on (0 0 1)Si were found to be heavily faceted and the shape of the faceted epitaxial CoSi 2 nanodot was identified to be inverse pyramidal. The observed results present the exciting prospect that with appropriate controls, the PS NSL technique promises to offer an effective and economical patterning method for the growth of a variety of large-area periodic arrays of uniform metal and silicide nanostructures on different types of silicon substrates.

Single-layer graphene was grown on copper at a low temperature of 600°C by plasma-assisted thermal chemical vapor deposition. Its growth mechanism was discussed with reference to the emission spectra of the plasma. The methane plasma produces the active species (Hx, CHx, and Cx) without the addition of flowing hydrogen, and the amounts of hydrogen-containing species can be controlled by varying the plasma power. The effective distance was found between the plasma initial stage and the deposition stage for the single-layer graphene synthesis. The results reveal that high-quality graphene can be synthesized using methane plasma at a suitable plasma power.

In this study, we investigate the directivity of the terahertz (THz) radiation pattern from a newly designed two-dimensional rampart slot array antenna integrated in an edge-coupled membrane photonic transmitter. The antenna design is based on the array theory which is well-developed in the microwave regime. By means of the array arrangement of rampart slot antennas, we demonstrate that the 3-dB beam width of the THz radiation pattern at 907 GHz is successfully confined within 30 in both and planes.

In general multi-stage fuzzy logic inference, there are three kinds of linguistic variables: input, output , and intermediate variables . When intermediate variables are present in a set of fuzzy rules to form multi-stage fuzzy rules, the inferring time involved is understandably lengthened. To achieve fast reasoning of multi-stage fuzzy logic, the number of fuzzy set operations of input, output, and intermediate variables must be decreased as much as possible without information loss. For the intermediate variables, the fuzzy logic operations of overlapped fuzzy value pairs on several multi-stage fuzzy rules may be pre-computed at compiling time. Furthermore, if the pre-computations have been done, the numbers of intersection and union scalar operations must also decrease in order to speed up reasoning at execution time. Moreover, whether fuzzy logic operations of multi-stage fuzzy rules are pre-computed or not, the types of fuzzy logic operators must be considered. Failing to do so may lead to information error. By using the Truck-Trailer Backer-Parking System , improvements over related methods are attained.

We successfully excited confined acoustic oscillations, which reflect the mechanical properties, in 2-D arrayed GaN nanorods with different diameters, by using femtosecond lasers. A nano-softening effect was observed when rod diameter was less than 150nm.