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Intrinsic silicon (Si) is forbidden for infrared (IR) sensing at the communication wavelength like 1.31 or 1.55 µm due to the well‐known bandgap limitation. In this work, an unexpected physical picture of using argon (Ar) is identified, which is usually inert to the surrounding chemical environment and used as a protective agent in semiconductor processing, to overcome the IR‐sensing‐forbidden problem in Si. Here, it is shown by an analysis of a dynamic secondary ion mass spectrometer that such a Si, when exposed to laser pulse in Ar gas, can contain a very high dose of Ar up to 1020 cm−3 even after 1300 days. First‐principles calculations, molecular dynamics, and Hall effect measurements reveal that, due to both steric and dynamic repulsions by Ar orbitals to Si dangling bonds, the Ar‐filled‐vacancy produces a much wider defect band inside the gap, which is not only responsible for strong infrared absorption, but also causes a significant increase in n‐type conductivity, both in line with experiments. The study proves that originally inert elements in fact can act as active impurities in semiconductors for advanced applications, which updates the current knowledge of defect physics. [ABSTRACT FROM AUTHOR]

Background: Mounting research indicates that brain-derived neurotrophic factor (BDNF), has great potential to increase neuro-hyperresponsiveness and airway resistance in airway allergic disease. The expression level of BDNF has been found to be notably elevated in lung/nasal lavage (NAL) fluid. However, the expression and position of BDNF in ciliated cells with allergic rhinitis remains unclear. Methods: Nasal mucosal cells were collected from patients with allergic rhinitis (AR) and mice which were performed under different allergen challenge time, then observed the expression and position of BDNF located in ciliated cells through the immunofluorescence staining. Nasal mucosa, serum and NAL fluid were collected also. The expression level of BDNF and IL-4/5/13 were detected by RT-PCR. The expressions of BDNF (in serum and NAL fluid), and total-IgE, ovalbumin sIgE (in serum) were detected by ELISA. Results: We found that MFI of BDNF in AR group's ciliated cells was obviously lower than that in the control group, and a negative correlation was discovered between MFI and VAS score. It can be roughly divided into 5 patterns according to its location in the cytoplasm of ciliated cells. In the mouse model, the expressions of BDNF in serum and NAL fluid increased temporarily after allergen stimulation. The MFI of BDNF in ciliated cells displayed an initial increase followed by a subsequent decrease. Conclusion: Our study shows for the first time that, the expression and localization of BNDF were observed in the human nasal ciliated epithelial cells of allergic rhinitis, and the expression of level was less than the control group under the persistent state of allergy. BDNF expression in ciliated cells was transient increased after allergen stimulation and decreased to normal level after 24h in mouse model of allergic rhinitis. This might be the possible source of the transient increase of BNDF in serum and NAL fluid. [ABSTRACT FROM AUTHOR]

Similar to some other countries in East Asia, Taiwan has been experiencing a dramatic increase in children born to cross-border mothers. This phenomenon has drawn national attention to the school performance gap between children of Taiwanese and immigrant mothers. The present study focuses on the factors associated with these academic performance differences, in particular differential access to social capital or resources, and the community context. Drawing on data from a stratified sample of 940 elementary students in a county in central Taiwan, the researcher first illustrates the educational disadvantage of children born to Southeast Asian mothers. Second, the shortage of within-family social capital is shown to contribute to the performance gap between schoolchildren within different maternal ethnic backgrounds. Third, students' preschool experience, educational attitudes, and behaviors all have positive association with their academic performance. In addition, the effects of within-family social capital and of maternal ethnic background can be moderated by community characteristics that show a broad picture of human capital, and socioeconomic status and heterogeneity of residents within school districts. [ABSTRACT FROM AUTHOR]

Drawing on data from the Survey of Foreign and Chinese Spouses' Living Requirements in 2013, we probe the effects of economic and acculturative factors on psychological well-being, particularly happiness, of female immigrants in cross-border marriages in Taiwan, while social demographic variables are controlled. In the economic aspect, while being employed negatively affects immigrant brides' happiness, family income, as expected, is positively associated with psychological well-being. However, during acculturation, immigrant brides who have stayed longer in Taiwan, especially for more than 10 years, report a lower level of happiness. Also, different types of social networks and resources may be available for them to cope with the difficulties encountered. Immigrant brides accessing professional organisations are more likely to report being 'very happy'. Finally, perceived friendliness is an important protective factor among female marriage immigrants. More interestingly, perceived friendliness plays a role in mediating the influence of economic and acculturative predictors on psychological well-being. [ABSTRACT FROM AUTHOR]

In pre-industrial Taiwan, an uxorilocal marriage, in which a man moved in with his bride's family, was a familial strategy used to continue family lineage and to enhance family farm labor. We examine the prevalence and circumstances in which a family would call in a man for one of their unmarried daughters. Using data from the Taiwan Historical Household Registers Database (THHRD) from 1906–1945, we identify the individual-level factors (including parental status, sibling status, household heads' occupations, and the capacity of the family labor force) and a community-level factor – the prevalence of uxorilocal marriages by region, which are predictive of uxorilocal marriages. Our analyses first show that women without siblings and women with only female siblings were more likely to adopt the uxorilocal form of marriage. In addition, the effects of siblings' status were moderated by the presence or absence of parents. For women without any male siblings with at least one parent, especially a father, residing in the household, the likelihood of having an uxorilocal marriage was higher than for those without any parents. Second, an uxorilocal marriage was less common in families with more young family members in the labor force to fulfill the manpower needed for farming. Third, uxorilocal marriage was more likely to occur in families living in the poorest socioeconomic conditions, especially those families in which household heads did not own land and had to sell their labor for agricultural production. Our findings imply that the adoption of uxorilocal marriage varied not only from place to place but also from time to time; it was conditioned by the modes and the means of labor production. [ABSTRACT FROM AUTHOR]

A crystalline silicon (Si) surface was modified using nanosecond laser pulses in an argon atmosphere. The laser-modified Si (M-Si) samples have a higher performance and thermostable absorption in the broadband range (400–2400 nm) than conventional Si. The concentration of carrier electrons in the M-Si layer is at least five orders of magnitude greater than the carrier concentration of the Si substrate. Using the N+–N− junction formed between the M-Si layer and the Si substrate, visible and near-infrared (VIS-NIR) M-Si photodetectors are made. The N+–N− photodiode has good rectification characteristics and a high photoresponse to the subbandgap NIR light at 1310 nm. At the same time, the M-Si photodetector at a low reverse bias shows a large gain to the VIS-NIR light above the bandgap. By comparing the response time of the M-Si photodetector to the light of 900 and 1310 nm, the response speed of the device to the photon above-bandgap energy is faster. [ABSTRACT FROM AUTHOR]

Micro-ripple and micro-bead structures are formed on a silicon (Si) surface after irradiation with femtosecond laser pulses in nitrogen (N2) atmosphere. Simultaneously, supersaturated nitrogen (N) atoms, with a concentration above 1020 cm−3, are doped into the textured black Si layer via laser ablation. The N-doped Si exhibits strong below-bandgap infrared absorption from 1.1 to 2.5~\mu \textm , which remains nearly unchanged after annealing for 30 min at 873 K. The mechanism of this thermally stable infrared absorption is analyzed by first-principles calculations. According to the transmission electron microscopy results, multiple phases (including single crystalline, nanocrystalline, and amorphous phases) are observed in the laser-irradiated layer. Hall Effect measurements prove that N-dopants induce a low background free-carrier concentration ( \sim 1.67\times 10^16\,\,\text cm^-3 ). Finally, a Schottky-based bulk structure photodiode is made. This broadband photodiode exhibits good thermal stability and a photo-responsivity of 5.3 mA/W for 1.31~\mu \textm at a reverse bias of 10 V. [ABSTRACT FROM PUBLISHER]

Microstructured silicon (Si) materials have been fabricated by femtosecond (fs) laser ablation and have been hyperdoped with gold (Au) impurities. The ablated Si materials showed large and thermostable infrared absorption at 1.1-2.5 μm wavelengths, which was contributed by sub-band absorption and laser-induced defects absorption. The Au-Si alloy was formed after laser irradiation onto the Au-coated Si surface, which was determined by XRD characterization. Using N-type Si substrate, the fabricated Au-doped Si performed lower sheet carrier density due to the self-compensation effect between deep donor and acceptor energy lever of Au in bulk Si material. From Hall measurement, both the p- and n- types of Au-doped Si samples can be obtained by controlling the type of Si substrate. [ABSTRACT FROM AUTHOR]

Gold (Au)-doped-textured silicon (Si) material with a thermostable absorption below bandgap (>50%) is obtained by femtosecond laser irradiation. Although the concentration of Au impurity (1019 cm−3 ) in textured Si is at least four orders of magnitude greater than the solid solubility of Au in crystalline Si, the sheet carrier density (approximately 1010 cm−2) in Au-doped Si is very low due to a self-compensation effect of Au impurity in Si material. The infrared absorption of Au-doped Si is related to laser-induced-structural defects and sub-band absorption of deep energy levels of Au in Si, which is determined by temperature-dependent Hall Effect measurement. Besides supersaturated doping of Au, a gold silicide phase is formed at textured Si surface. [ABSTRACT FROM PUBLISHER]

Femtosecond (fs) laser annealing has been applied to improve the crystalline quality and absorptance below bandgap of ion implanted silicon (Si) with sulfur (S). The doping concentration of S is up to 10^20 atoms/cm3, which is at least four orders of magnitude higher than the solid solubility of S in crystalline Si. According to the Raman spectra, after fs laser irradiation with appropriate laser energy, the crystal quality is evidently better than primary ion implanted sample. Moreover, the optical absorption coefficient at wavelengths of 1100~2400 nm is up to 1.54 \times 10^4 cm ^\mathrm -1 , which is much larger than the contribution of free carriers. Excessive laser energy will induce serious ablation effect and cause the removing of doping layer. We consider that the high absorption is a combination of sub-bandgap transition of S-related localized states, free carrier absorption, ion implantation induced defect absorption and fs laser irradiation induced defect absorption. In the end, a photo-response of 8.4 mA/W is obtained for the photodiode for 1310 nm detection light. [ABSTRACT FROM PUBLISHER]

Purpose Since the 1990s, an imbalanced marriage market has ushered in a great number of female immigrants, mainly from China and certain ASEAN countries, into Taiwan. These immigrant brides lose their original social networks and face difficulties acculturating, which in the long run may take a toll on their psychological well-being. The purpose of this paper is to identify what the factors are and how they are associated with the symptoms of depression and anxiety among immigrant brides.Design/methodology/approach Due to the difficulty of identifying immigrant brides within the general population, the research relies on a convenience sample of 366 immigrant brides in eight cities or counties in Taiwan. The research team provided questionnaires in different languages including Traditional Chinese, Simplified Chinese, English, Vietnamese, Thai, and Indonesian. Surveyed immigrant brides filled in questionnaires while participating in activities for Immigrant Day.Findings Hierarchical regression analyses show that perceived discrimination and sociocultural barriers are the two greatest factors causing depression and anxiety among immigrant brides. However, the effect of social support is not as clear as expected. Emotional social support from “the same ethnic group” is significant in reducing the symptoms of psychological depression of immigrant brides, but it cannot explain the variation in anxiety among immigrant brides.Originality/value Although the psychological well-being of immigrant brides in Taiwan is an important issue, little scholarly research has been published on this increasing segment of the population. The research can improve our understanding of the acculturation of immigrant brides in Taiwan. Meanwhile, the findings in the Taiwan-based research may provide further helpful knowledge for South Korea and China, both of which generally share a similar culture with Taiwan and are also facing the issues of marriage market imbalance and the increase of immigrant brides, in developing prevention and intervention strategies and/or programs to enhance the psychological well-being of immigrant brides. [ABSTRACT FROM AUTHOR]

Supersaturated S-doped black silicon (Si) samples are produced by femtosecond laser fabrication in mixed atmosphere of sulfur hexafluoride and oxygen (SF6/O2). The surface morphology with cone-microstructures has been observed in black Si samples fabricated in mixed atmosphere. After thermal annealing, the absorption below bandgap of black Si is obviously reduced. Moreover, the contents of sulfur in black Si samples obtained in mixture are also decreased by the lead in of oxygen. In contrast, an obvious increase of valent state ratio of Si4+ (SiO2) to Si0 (Si) is observed after the implantation of oxygen due to the formation of SiO2 in S-doped Si. Based on the passivation effect of SiO2, we have produced near-infrared black Si photodiode devices and showed photo-response properties of the devices. A notable photo-response of 11 mA/W at −3 V (26.6 mA/W at −5 V) for near-infrared 1.31- \mu \textm detection light is obtained for the photodiode fabricated in mixture, which outweigh the performance of photodiode fabricated in pure SF6 atmosphere. [ABSTRACT FROM PUBLISHER]

Co-doped black silicon with sulfur and nitrogen impurities was fabricated by a femtosecond laser in a mixed atmosphere of N2 and SF6. Compared with sulfur-doped black silicon, the infrared absorption of co-doped black silicon shows excellent thermal stability, indicating that the high absorption below the band-gap of silicon is insensitive to the thermal annealing process. According to the electronic nature of annealed co-doped black silicon by the Hall-effect measurement, the sheet carrier density decreases with increasing nitrogen content as a result of the neutral doping of the nitrogen pair defect. Furthermore, a near-infrared black silicon photodiode was produced based on the performance of the stable absorption for thermal annealing and its superior photo-response, in which 58 mA/W is obtained for the photodiode for a 1.31- \mu \textm detection light. [ABSTRACT FROM PUBLISHER]

Inspired from butterfly wings that exhibit unique dewetting properties and brilliant structural color synchronously, we reported here the preparation of biomimetic few-layer graphene films through a template-directed chemical vapor deposition method using laser-structured Cu foil as substrates. Hierarchical micronanostructures, including microscale stripes derived from the laser scanning and nanoscale laser-induced periodic surface structures (LIPSS), formed on Cu foil after a simple femtosecond laser treatment. By tuning the laser power, the surface roughness of the resultant Cu foils can be well controlled. Using the laser structures Cu foil as templates, biomimetic few-layer graphene films with both iridescence and superhydrophobicity have been successfully prepared. The present work may open up a new way to design and prepare structured graphene film in a biomimetic manner, and we deem that the bioinspired few-layer graphene films may find broad applications in the near future. [ABSTRACT FROM AUTHOR]

We investigated the strain and surface structural properties of a strain-relaxed Si1–xGex alloy layer with high Ge-content using optical surface second-harmonic generation. Here, the Si1–xGex alloys are heteroepitaxial, and they are deposited onto Si substrates via ultra-high-vacuum-chemical vapor deposition. The in-plane strain and the composition $x$ of the Si1–xGex alloys were determined using Raman spectroscopy. The SH signals generated from three Si1–xGex alloy surfaces versus the rotational angle of the substrate were measured. The SH intensities for the combination of s-input/p-output polarization show fourfold symmetry; however, for s-input/s-output, the SH signals show eightfold symmetry with the rotational angle. Residual strain would induce an enhancement of the isotropic p-output SH component in the Fourier transform coefficient. Finally, the degree of symmetry of the SH signals from these three Si1–xGex alloy surfaces versus the rotational angle was related with the surface pit defects (densities and sizes) and surface roughness. [ABSTRACT FROM AUTHOR]

Micronanostructured silicon surface is irradiated by femtosecond laser pulses at sulfur hexafluoride atmosphere (S-doped black silicon) and photodiodes are successfully fabricated based on this material. From the scanning electronic microscope and atomic force microscope images, the black silicon layer shows micro-nanocomplex structures (microcones covered with nanoparticles). The optoelectrical properties of n+-p junction are formed between S-doped micro-nanostructured silicon-layer and substrate after thermal annealing. For the n+-p photodiode, current–voltage characteristics at different incident light powers have been investigated. The responsivity for 800-nm wavelength is 0.69 A/W at −5 V reverse bias, which is close to that of the usual commercial Si p-i-n photodiode. The present devices are stable and well reproducible. [ABSTRACT FROM PUBLISHER]

Chalcogen-doped microstructural silicon irradiated by femtosecond laser has high near-uniform absorption on a broad spectrum, but the factors leading to infrared absorption are complex and remain an open problem. To clarify the origin of infrared absorption besides hyperdoped Chalcogen atoms, microstructural silicon is fabricated by femtosecond laser under vacuum condition. The relationship between infrared absorption and as-formed new phases (amorphous silicon: $\alpha $ -Si and nanocrystal silicon) is established. It indicates that the infrared absorption is caused by defects related to Urbach states from \alpha $ -Si or nanocrystal Si, and these metastable defects disappeared after a thermal annealing process. From the absorption spectrum of microstructural silicon after etching at different times, it could be figured out that the Urbach states exist in both the surface and subsurface regions of black silicon at a depth of about 2.4 \mu \text{m} . [ABSTRACT FROM PUBLISHER]

Social scientists have under-examined neighborhood stores and other 'resources' and their relationships to community welfare and personal happiness. Because the presence of neighborhood conveniences may signify that a neighborhood caters to residents' needs and smoothes out the hassles of their daily lives, it could be hypothesized that commercial amenities and services enhance individuals' satisfaction with their neighborhoods, with their health, and even with their lives as a whole. This study used a national probability sample from Taiwan, a densely populated society in East Asia, to test if service-oriented commercial and religious enterprises in neighborhoods are associated with positive estimations of well-being by those who occupy these spaces. We empirically examine whether proximity to main roads, night markets and temples or proximity to smoky food stands and other shops that produce pungent products affects well-being. Our findings from multivariate analyses suggest that if nearby conveniences are conceived as annoyances, they tend to lower satisfaction with neighborhood, but they do not lower life satisfaction in general. In contrast, air quality, along with 'peace and quietness' is reported by respondents to be key in enhancing general well-being. We discuss the policy implications in the concluding session. [ABSTRACT FROM AUTHOR]

The regular micrometer-scale triangular arrays were formed using ultrafast femtosecond laser irradiation on (111) surface of silicon wafer immersed in KOH solution (0.1 g/ml). At low laser fluence, the resulting surface is covered by triangular pits microstructures, whereas at high laser fluence, the structures are transformed to multilayer-triangular stacks-microstructures. The number of triangular stacks layer increased as the laser fluence increased. The formation of triangle microstructure arrays depends on both silicon surface crystallographic orientation and the concentration of KOH solution. Either for lower KOH solution concentration (0.02 g/ml) or other silicon crystallographic orientation, triangle arrays cannot be obtained. We attribute the formation of triangular microstructure arrays to the laser-assisted chemical etching process. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The regular micrometer-scale triangular arrays were formed using ultrafast femtosecond laser irradiation on (111) surface of silicon wafer immersed in KOH solution (0.1 g/ml). At low laser fluence, the resulting surface is covered by triangular pits microstructures, whereas at high laser fluence, the structures are transformed to multilayer-triangular stacks-microstructures. The number of triangular stacks layer increased as the laser fluence increased. The formation of triangle microstructure arrays depends on both silicon surface crystallographic orientation and the concentration of KOH solution. Either for lower KOH solution concentration (0.02 g/ml) or other silicon crystallographic orientation, triangle arrays cannot be obtained. We attribute the formation of triangular microstructure arrays to the laser-assisted chemical etching process. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Buckner () extensively reviewed theoretical concepts proposed by a variety of scholars and developed the Neighborhood Cohesion Instrument (NCI) to measure three latent constructs (attraction to neighborhood, neighboring, and psychological sense of community). This instrument has been applied in most Western countries. The purpose of this research is to use Taiwan as a case study to assess whether the NCI can be applied to community research in an East Asian country. The authors apply confirmatory factor analysis to analyze two datasets collected in Taipei and the rural areas in Taiwan, separately. After scrutinizing the model fit indices and estimates of internal consistency, composite reliability and variance extracted, the authors conclude that the NCI can at least survey individuals in this particular East Asian country, Taiwan. By removing variables with small factor loadings and complex variables, researchers can develop a simplified model for further studies. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A novel diode-pumped Nd:YAG laser system that employs a fixed active laser medium and a pair of quick-change output couplers on a precision linear stage for 1064 or 532 nm wavelength generation is presented. Fixed elements include a rear mirror, an acousto-optical Q-switch, and a diode-pumped solid-state laser (DPSSL). Movable elements for 1064 nm generation include an intra-cavity aperture as a mode selection element (MSE) and an output coupler. Movable elements for 532 nm generation include an intra-cavity frequency conversion with KTP, an intra-cavity aperture as a mode selection element (MSE), and an output coupler. Under stable operating conditions, the 1064 nm configuration produced a beam propagation ratio of 1.18 whereas the 532 nm configuration produced a beam propagation ratio of 1.1, both of which used an intra-cavity MSE with an aperture of 1.2 mm and a length of 5 mm. [ABSTRACT FROM AUTHOR]