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In this paper, we investigated the electrical properties of the Metal-oxide-semiconductor gate stack of Ti/Al2O3/InP under different annealing conditions. A minimum interface trap density of 3×1011cm-2eV-1 is obtained without postmetallization annealing treatment. Additionally, utilizing Ti/Al2O3/InP MOS gate stack, we fabricated ultra-thin body buried In0.35Ga0.65As channel MOSFETs on Si substrates with optimized on/off trade-off. The 200nm gate length device with extremely low off-current of 0.6nA/µm, and on-off ratio of 3.3×105, is demonstrated by employing buried low indium (In0.35Ga0.65As) channel with InP barrier/spacer device structure, giving strong potential for future highperformance and low-power applications.

Multicomponent oxide (GaxIn1−x)2O3 films are prepared on (0001) sapphire substrates to realize a tunable band-gap by magnetron sputtering technology followed by thermal annealing. The optical properties and band structure evolution over the whole range of compositions in ternary compounds (GaxIn1−x)2O3 are investigated in detail. The X-ray diffraction spectra clearly indicate that (GaxIn1−x)2O3 films with Ga content varying from 0.11 to 0.55 have both cubic and monoclinic structures, and that for films with Ga content higher than 0.74, only the monoclinic structure appears. The transmittance of all films is greater than 86% in the visible range with sharp absorption edges and clear fringes. In addition, a blue shift of ultraviolet absorption edges from 380 to 250 nm is noted with increasing Ga content, indicating increasing band-gap energy from 3.61 to 4.64 eV. The experimental results lay a foundation for the application of transparent conductive compound (GaxIn1−x)2O3 thin films in photoelectric and photovoltaic industry, especially in display, light-emitting diode, and solar cell applications.

Theoretical studies of ultra-thin silicon solar cells with cylindrical, conical and parabolic surface nanostructures inherited from natural self-assembled anodic alumina oxide (NSA-AAO) were performed by finite-difference time-domain (FDTD) method. All nanostructured solar cells obtained an optimized efficiency enhancement as high as more than 33% comparing with that of the anti-reflective (AR) one. Numerical results reveal that the range of efficient structural parameters for the nanostructured (e.g., cylindrical) solar cell can be effectively enlarged as the period of the nanostructure changes from 0.1 μm to 0.5 μm. Moreover, the improvements of absorption photocurrent density (Jph) in conical and parabolic nanostructured solar cells are comparable with the cylindrical nanostructured one but less sensitive to the fill factor and structural height in the whole simulation region of 0.1-0.9 and 0-0.25 μm, respectively. Equivalent refractive index models were used to analysis the antireflection performance of surface nanostructures from the point of view of sidewall profiles. Resonance modes induced through nanostructures have greatly improved the absorptance of solar cells in broadening wavelength bands which consequently raised the Jph. This study serves as a way for the practical design and application of AAO nanostructure based high-efficiency ultra-thin solar cells.

Objectives. To investigate the association of serum autoantibodies against M2-muscarinic acetylcholine receptor (anti-M2-R) with atrial fibrosis in long-standing persistent atrial fibrillation (AF) patients. Methods. Twenty-four long-standing persistent AF patients, scheduled to undergo hybrid ablation surgery, were enrolled in the study. Twenty-six patients with sinus rhythm, scheduled to undergo coronary artery bypass grafting surgery, were enrolled into the non-AF group. We detected serum anti-M2-R levels. Left atrial appendages were subjected to histological and molecular biological assays. Patients in the AF group received follow-up for two years. Results. The AF group showed significantly higher serum anti-M2-R levels compared to the non-AF group (496.2 ± 232.5 vs. 86.3 ± 25.7 pmol/L, p<0.001). The AF group exhibited severe fibrosis in the left atrial appendages, as indicated by increased collagen volume fraction (45.2 ± 4.7% vs. 27.6 ± 8.3%, p<0.001), and higher levels of collagen I (0.52 ± 0.04 vs. 0.24 ± 0.06, p<0.001) and collagen III (0.51 ± 0.07 vs. 0.36 ± 0.09, p<0.001). TGF-β1 and CTGF were also upregulated in the AF group. A positive correlation between serum anti-M2-R levels and fibrosis of the left atrial appendage and fibrogenic indexes was observed. Conclusions. Serum anti-M2-R levels are higher in AF patients and are associated with the severity of atrial fibrosis. In addition, serum anti-M2-R levels are positively correlated to TGF-β1 and CTGF expression in the left atrial appendage.

Herein, we propose a tunable plasmonic sensor with Fano resonators in an inverted U-shaped resonator. By manipulating the sharp asymmetric Fano resonance peaks, a high-sensitivity refractive index sensor can be realized. Using the multimode interference coupled-mode theory and the finite element method, we numerically simulate the influences of geometrical parameters on the plasmonic sensor. Optimizing the structure parameters, we can achieve a high plasmonic sensor with the maximum sensitivity for 840 nm/RIUand figure of merit for 3.9 × 105. The research results provide a reliable theoretical basis for designing high sensitivity to the next generation plasmonic nanosensor.

Surface anti-reflection (AR) with micrometer or nanometer scaled surface texture has been studied extensively and showed excellent light extraction (or harvest) performance in corresponding opto-electronic devices. In this paper, a 2-inch anodized aluminum oxide (AAO) template with nano/micro hybrid structure was obtained directly through a simple lithography-free aluminum anodization process for the first time. This new nano/micro hybrid structure combines the advantages of sub-100 nm sub-wavelength structure (SWS) and micrometer scaled surface roughening. Aluminum grains were found to rearrange the distribution of the penetrated surface current during the anodization and eventually induced the micrometer scaled fluctuation underneath. The ultra-thin AAO replication scheme was introduced to fabricate and study the spectrum (300 nm to 800 nm) dependent AR performance of the nano/micro hybrid PDMS structure, which obtained an AR enhancement fraction of more than 42% higher than that of the nano-patterned one. Thin film and GaN based light-emitting diode (LED, 450 nm) models were built and studied. Compared to the flat LED, the AR enhancement of the nano/micro structured one can reach as high as more than 3 folds. These results suggest the nano/micro hybrid structure could be a good alternative for the applications of surface AR structure.

The positive bias temperature instability (PBTI) reliability of buried InGaAs channel n-MOSFETs with an InP barrier layer and Al2O3 gate dielectric under medium field (2.7 MV/cm) and high field (5.0 MV/cm) are investigated in this paper. The Al2O3/InP interface of the insertion of an InP barrier layer has fewer interface and border traps compared to that of the Al2O3/InGaAs interface. The subthreshold slope, transconductance, and shift of Vg are studied by using the direct-current Id-Vg measurements under the PBTI stress. The experimental results show that the degradation of positive ΔVg under the medium field stress is mainly caused by the acceptor trap, while the donor trap under the high field stress become dominant in the subthreshold region, which leads to the negative shift in Vg. The generation of acceptor trap are attributed by the InP barrier layer in the buried InGaAs channel n-MOSFETs, resulting that the part of recoverable donor trap has been neutralized under the high field stress. Compared to the surface InGaAs channel n-MOSFETs under PBTI stress, the low leakage current can be achieved in the buried InGaAs channel n-MOSFETs with an InP barrier layer.

A novel SiC/Si heterojunction lateral double-diffused metal-oxidesemiconductor (LDMOS) with a reversed L-shaped field plate and a stepped oxide layer has been proposed to improve the tradeoff between the breakdown voltage (BV) and specific on-resistance (Ron,sp). The reversed L-shaped field plate is applied to modulate electric field distribution to make the breakdown occur in the low electric field area (SiC/Si interface), which increases the BV and decreases the Ron,sp of the device. Furthermore, a stepped oxide layer is used to cover the Si drift region and reshape the lateral electric field distribution by introducing a new electric field peak, which consequently enhances the BV. The simulated results have indicated that the BV of this proposed SiC/Si LDMOS increased from 226 V and 720 V to 992 V compared with the conventional Si LDMOS and SiC LDMOS, respectively, while maintaining a low Ron,sp of 27.62 mΩ·cm2.

We propose a broadband structure which integrates polarization and nanofocusing functions into a single device with 3.8×4 µm 2 footprint. The bandwidth is over 200 nm with insert loss (IL) smaller than 1.68 dB.

Spot size conversion from the Si waveguide core (400×220 nm2) to a plasmonic waveguide core (20×40 nm2) is studied with insert loss (IL) 1.29 dB and extinction ratio (ER) 29.3 dB.

High density honeycombed nano-pattern of anodic aluminum oxide (AAO) is of great use to various high-performance optoelectronic devices due to its non-lithographic and excellent sub-wavelength structure (SWS) anti-reflection (AR) properties. In this paper, we introduce an ultra-thin AAO based bilayer polydimethylsiloxane (PDMS) scheme to simply replicate and obtain regular triangle-like surface nano-pillar array with a period of 125 nm, which shows a 5% to 27% AR enhancement under the light wavelength ranging from 250 nm to 850 nm. In order to investigate the intrinsic property of AAO nano-structure based light extraction properties, gallium nitride (GaN) light-emitting models are built. Compared to the bare GaN, the maximum AR enhancements of low ordered AAO array, regular array and high ordered AAO array are respectively 20.2%, 22.0% and 23.5%. Grain size effect is found to further improve the AR performance of the high ordered AAO array and the effective refractive index based thin film model demonstrates a success in AAO pattern-dependent surface AR analysis. Besides, by tailoring the side-wall profile, a further AR enhancement (e.g. 39.1%) can be obtained because of a smoothly changing of the refractive index along the height direction.

Grassland fire disasters have occurred frequently and adversely affected livestock agriculture and social-economic development greatly in the grassland regions of Jilin province, China. Moreover, both the frequency of grassland fire and loss from them are considered to be increasing with the global warming and economic development. This study presents a methodology for risk analysis and assessment of grassland fire disaster, taking western Jilin province as a case study area based on geographic information system (GIS). The composite grassland fire disaster risk index (GFDRI) combined the hazard of grassland fire, the exposure of the region, the vulnerability and emergency response and recovery capability for grassland fire disaster of the region were developed to assess and compare risk of grassland fire disaster in different counties in western Jilin province, China using the natural disaster risk index method (NDRIM), analytic hierarchy process (AHP) and weighted comprehensive method (WCM). Then, the risk degree of grassland fire disaster was assessed and regionalized in the western Jilin province, China based on GFDRI by using GIS. It is shown that the most places of western Jilin province were in mediate risk. Zhenlai, Tongyu were in heavy risk. Taobei, Ningjiang, Fuyu were in light risk. The information obtained from interviewing the district official committees in relation to result compiled was statistically evaluated. The GFDRI was developed to be an easily understandable tool that can be used to assess and compare the relative risk of grassland fire disaster in different counties in t western Jilin province, China, and to compare the different relative contributions of various factors, e.g., frequency of grassland fire and quality of emergency evacuation plan. The GFDRI is specifically intend to support local and national government agencies of grassland fire disaster management as they (1) make resource allocation decisions; (2) make high-level planning decisions; and (3) raise public awareness of grassland fire disaster risk, its causes, and ways to manage it.

Termination of persistent atrial fibrillation (AF) is a valuable ablation endpoint but is difficult to anticipate. We evaluated whether temporal and spatial indices of AF regularization predict intraprocedural AF termination and outcome.The purpose of this study was to test whether temporospatial organization of AF after pulmonary vein isolation (PVI) predicts whether subsequent stepwise ablation will terminate persistent AF or predict outcome.In 75 patients with persistent AF, we measured AF cycle length (AFCL), temporal regularity index (TRI, a spectral measure of timing regularity), and spatial regularity index (SRI, cycle-to-cycle variations in spatial vector) between right atrial appendage and proximal and distal coronary sinus before and during stepwise ablation to the endpoint of AF termination.AF termination was achieved in 59 patients (79%) by ablation. AF terminated during PVI in 11 patients, who were excluded from analysis. In the remaining 48 patients, TRI and SRI increased during stepwise ablation, as compared with 16 patients without termination (P.05). AFCL was prolonged in both groups. From receiver operating characteristics analysis of the first 22 patients (training set), a post-PVI TRI increase predicted AF termination in the latter 42 patients (test set) with a positive predictive value of 96%, negative predictive value of 53%, sensitivity of 71%, and specificity of 91%. Results were similar for SRI. After 36 months, higher arrhythmia-free outcome was observed in patients in whom PVI caused temporospatial regularization in AF.Temporal and spatial regularization of persistent AF after PVI identifies patients in whom stepwise ablation subsequently terminates AF and prevents recurrence.

Background It has been shown that serum free thyroxine (FT4) concentration is independently associated with atrial fibrillation (AF) even in euthyroid persons. This study aimed to testify the impact of high-normal level of FT4 on recurrence after catheter ablation of AF. Methods Two hundred and forty-four consecutive patients with paroxysmal AF underwent circumferential pulmonary vein isolation (PVI) were prospectively enrolled. Exclusion criteria included prior or current thyroid dysfunction on admission, amiodarone medication for three months before admission. Results After a mean follow-up of 416±204 (91–856) days, the recurrence rates were 14.8%, 23.0%, 33.3%, 38.7% from the lowest FT4 quartile to the highest FT4 quartile, respectively (p=0.016). Adjustment for age, gender, left atrium diameter, PVI, there was an increased risk of recurrence in the subjects with the highest FT4 quartile compared with those with the lowest quartile (HR 3.31, 95% CI 1.45 to 7.54, p=0.004). As a continuous variable, FT4 was also an independent predictor of recurrence (HR 1.10, 95% CI 1.02 to 1.18, p=0.016). Conclusions Patients with high-normal thyroid function were at an increased risk of AF recurrence after catheter ablation.

Background HATCH score (1*hypertention+1*[age>75]+2*[stroke or transient ischaemic attack]+1*[chronic obstructive pulmonary disease]+2* [heart failure]) is an established predictor of progression from paroxysmal to persistent atrial fibrillation (AF). Whether atrial remodelling indexed by HATCH score could be a predictor of recurrence after catheter ablation of AF needs to be explored. Methods The data of 608 consecutive AF patients who underwent an index circumferential pulmonary veins ablation were retrospectively analysed. Of these patients, 313 (51.5%) patients had HATCH=0, 225 (37.0%) patients had HATCH=1, 70 (11.5%) patients had HATCH≥2. Results The patients with HATCH≥2 had significantly the largest left atrium size, the largest left ventricular end systolic diameter, and the lowest ejection fraction among the three HATCH categories. There were significant differences of the proportion of diabetes mellitus, statins medication, and angiotensin-converting enzyme inhibitors/angiotensin receptor blockers medications among the three HATCH categories. After a mean follow-up of 474±330 days, the recurrence rate were 36.4%, 38.7%, 34.3%, from HATCH=0 to HATCH≥2 categories (p=0.707). Univariate analysis revealed that nonparoxysmal AF, left atrium size, body mass index were predictors of AF recurrence. Multivariate analysis revealed that nonparoxysmal AF (HR=1.43, 95% CI 1.03 to 1.99, p =0.031) was the only independent predictor of AF recurrence. HATCH and left atrium size were not independent predictors of AF recurrence. Conclusion HATCH has no value in prediction of AF recurrence after catheter ablation.

Objective This study sought to investigate the impact of ageing on left atrium thrombus in patients with non-valvular atrial fibrillation (AF). Methods Four hundred and twenty-one consecutive patients with AF underwent transesophageal echocardiography prior to AF ablation were included in a prospectively established database. The elderly group was defined as age more than 65 years old. Results In all the 421 patients, 108 (25.6%) were in the elderly group and 313 (74.4%) were in the young group, with the mean age 70.0±3.7, 52.1±8.5, respectively. There was no significant difference of left atrium thrombus between the elderly group and the young group (4.6% vs 6.7%, p=0.439). It was shown there is less value for age predicting left atrium thrombus, the area under the receptor-operating curve was 0.494. The mean age (56.7±9.9 vs 56.7±10.9, p=0.989) and the proportion of the elderly (19.2% vs 26.1%, p=0.439) did not differ significantly between the patients with left atrium thrombus and those without. After adjustment for ejection fraction, heart failure, hypertension, diabetes mellitus, angiotensin-converting enzyme inhibitors/angiotensin receptor blockers medication in logistics multivariate analysis, left atrium diameter, non-paroxysmal AF, prior thromboembolic history were independent risk factors of left atrium thrombus. However, age was not an independent risk factor of left atrium thrombus. Conclusions Ageing itself was not a risk factor of left atrium thrombus in patients with non-vavular AF.