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The human microbiome plays an important role in autoimmune diseases. However, there is limited knowledge regarding the microbiota in individuals with primary Sjögren's syndrome (pSS). Here, we perform 16S ribosomal RNA gene sequencing of fecal, oral, and vaginal samples from a cohort of 133 individuals with pSS, 56 with non-pSS, and 40 healthy control (HC) individuals. Dysbiosis in the gut, oral, and vaginal microbiome is evident in patients with pSS, and oral samples demonstrate the greatest extent of microbial variation. Multiple key indicator bacteria and clinical characteristics are identified across different body sites, implying that microbial dysbiosis has important roles in the pathogenesis of pSS. Furthermore, we observe pSS-like dysbiosis in individuals with pre-clinical pSS or non-pSS-related disease, revealing that microbial shifts could appear prior to pSS. After hydroxychloroquine (HCQ) treatment, microbial dysbiosis in individuals with pSS is partially resolved, although the microbiota composition remain disordered. These results contribute to the overall understanding of the relationship between the microbiome and pSS.

Alterations of biological pathways can lead to oncogenesis. An overview of these oncogenic pathways would be highly valuable for researchers to reveal the pathogenic mechanism and develop novel therapeutic approaches for cancers. Here, we reviewed approximately 8500 literatures and documented experimentally validated cancer-pathway associations as benchmarking data set. This data resource includes 4709 manually curated relationships between 1557 paths and 49 cancers with 2427 upstream regulators in 7 species. Based on this resource, we first summarized the cancer-pathway associations and revealed some commonly deregulated pathways across tumor types. Then, we systematically analyzed these oncogenic pathways by integrating TCGA pan-cancer data sets. Multi-omics analysis showed oncogenic pathways may play different roles across tumor types under different omics contexts. We also charted the survival relevance landscape of oncogenic pathways in 26 tumor types, identified dominant omics features and found survival relevance for oncogenic pathways varied in tumor types and omics levels. Moreover, we predicted upstream regulators and constructed a hierarchical network model to understand the pathogenic mechanism of human cancers underlying oncogenic pathway context. Finally, we developed `CPAD’ (freely available at http://bio-bigdata.hrbmu.edu.cn/CPAD/), an online resource for exploring oncogenic pathways in human cancers, that integrated manually curated cancer-pathway associations, TCGA pan-cancer multi-omics data sets, drug–target data, drug sensitivity and multi-omics data for cancer cell lines. In summary, our study provides a comprehensive characterization of oncogenic pathways and also presents a valuable resource for investigating the pathogenesis of human cancer.

This paper presents the impact of FDSOI back gate biasing on circuit conducted emission. The back gate bias can modulate front gate electrical characteristic, and changing the circuit performance and power consumptions dynamically. Meanwhile, the electromagnetic emission of circuit is changing with the back gate variation. A ring oscillator is tested to illustrate the relation between back gate biasing and the conducted emission of the ground pin. The results shows the strong relation of the conducted emission with the front gate electrical parameters.

The radiation effects of metal-oxide-semiconductor (MOS) capacitors based on an Al2O3 gate dielectric were studied using 30 MeV Si heavy ions. To give insights into the types of defects induced by Si ion irradiation in the gate oxide, synergistic experiments involving γ-ray irradiation and Si ion irradiation were carried out. The results revealed that the defects in the as-grown Al2O3 layer were found to be hole trapping centers, whereas Si ion induced new defects were electron trapping centers. The experimental and simulation data of current density-voltage (J-V) curves confirmed that the transmission mechanism of leakage current in the Al2O3 layer was mainly dominated by the Frenkel-Poole mechanism. In detail, the variations of leakage current were mainly due to the attributions of the local built-in electric field-assisted current leakage and the conductive path-assisted current leakage and were found to be dependent on the irradiation condition and Al2O3 thickness. Lastly, the decrease of the gate oxide capacitance of MOS capacitors was attributed to the increase of the series resistance and leakage current in MOS capacitors.

In our work, insights into the total dose response and native point defect behavior in the Al2O3 gate dielectric during irradiation were gained by gamma-ray irradiation experiments and first-principles calculations. It is found that the O vacancy (VO) can act as a hole trap in the Al2O3 gate dielectric during irradiation, leading to the negative shift of the capacitance–voltage (C–V) curves of the Al2O3-based metal–oxide–semiconductor (MOS) structure. Our calculations show that the neutral defect VO becomes a +2 charged center after irradiation, and the positively charged VO is a kind of conductive path for electrons, which contributes to an increase of the leakage current in the irradiated MOS capacitors. Additionally, the trapped holes are accumulated with irradiation doses, which can lower the barrier height of the Al2O3 gate oxide and further cause the increase of the leakage current. The other native point defects in the Al2O3 layer, such as aluminum vacancy (VAl), aluminum interstitial (Ali) and oxygen interstitial (Oi), only act as fixed charge centers during irradiation. Net negative charges existing in the Al2O3 layers before irradiation are mainly induced by the negatively charged defects of VAl and Oi.

In this paper, we analyze light transmission through a single subwavelength slit surrounded by periodic grooves in layered films consisting of Au and dielectric material. A subwavelength grating is scanned numerically by the finite difference time domain method in two dimensions. The results show that the transmission field can be confined to a spot with subwavelength width in the far field and can be useful in the application of a high-resolution far-field scanning optical microscope

We have fabricated surface plasmon modulated nano-aperture vertical-cavity surface-emitting lasers (VCSELs) from common 850 nm VCSELs using focus ion beam etching with Ga+ ion source. The far-field output power is about 0.3 mW at a driving current of 15 mA with a sub-wavelength aperture surrounded by concentric periodic grooves. The enhancement of transmission intensity can be explained by diffraction and enhanced fields associated with surface plasmon. This structure also exhibits beaming properties.

Special characteristics of very-small-aperture lasers are observed, including threshold current change, red shift of the spectral position, and short lifetime at low drive current. Physical mechanisms that underlie these special characteristics are analyzed: we find that optical feedback caused by a metal film and heat accumulation inside the laser diode lead to the special characteristics of VSALs, such as threshold current change, red shift of the spectral position, and short lifetime at low drive current, etc. Theoretical simulation is in good agreement with the experimental results.

We report on a VSAL structure fabricated by a 650 nm edge emitting laser diode with an Au-coated facet and an aperture size of 250 × 500 nm. The far field output power can maintain at 1 mW and the power density is 7.5 mW/μm2. Some properties of the VSAL including the threshold current change, the red-shift of the spectral position, and the strong relative-intensity-noise are presented. The physical mechanisms responsible for these phenomena are also discussed, which may contribute to the understanding and application of the potential device for near-field optics.

The adhesion of Deoxyribose Nuclei Acid (DNA) on an electrode surface such as silicon is a key issue in the sensitivity of DNA chips, in order to maximize the DNA concentration on the electrodes of DNA chips and increase the detected signal, the chip should have good adhesion of DNA to its electrodes. In our study, several pieces of silicon wafer were treated by argon and oxygen plasma, respectively. We analyzed the DNA content on the different silicon surfaces using the X-ray photoelectron spectroscopy (XPS). The results indicate that the content of DNA molecules adhered on the silicon surface treated with an oxygen plasma is higher than that on the surface treated with an Ar plasma. This can be interpreted in terms of the interaction of parasitic charges and van der Waals forces on silicon oxide surfaces.

A hard disk medium is typically composed of several layers including the magnetic recording layer, a buffer layer, as well as a wear protective layer. In the work presented here, the hard disks analysed have a total of five layers with the uppermost layer being the lubricant. The second layer is diamond like coating and this is followed by the magnetic layer consisting of an alloy of cobalt and other elements. The fourth layer is a buffer composed of an alloy of chromium, vanadium and molybdenum with the final layer being a nickel transition layer doped with phosphorus. These multilayers were subjected to numerous etchings by argon ions. The chemical structures of these layers were analysed with an X-ray photoelectron spectroscope (XPS) after each etching. Combining the XPS spectra with XPS imaging it is possible to determine the depth distribution of elements in the hard disk coating. In addition, it is also shown that XPS imaging can be employed to monitor the thickness of all multilayers.

Titanium nitride (TiN) thin films have low electrical resistivity, good chemical and metallurgical stability, and exceptional mechanical properties. As such, we are interested in exploring TiN for use as mold material for micro-and nano replication. Focused ion beam (FIB) technique was successfully used to fabricate sub-micron sized pattern on a TiN/Si(100) wafer. This mask-free fabrication technique takes advantage of the kinetic precision of FIB; the energy of ions used was 40 KeV. The width and depth of each trench in the TiN mold are 390 nm and 280 nm respectively.

Diamond-like carbon (DLC) films with different structure were deposited on highly electrically conductive silicon substrates (SiO ySi), using d.c. magnetron sputtering deposition process. Their structure and electrochemical behavior in a 0.5 M H SO 2 24 solution were studied with micro-Raman spectroscopy, electrochemical impedance spectroscopic analysis and film impedance spectroscopy. The combined polarization resistance of silicon coated with DLC film increased to approximately 10 –10 V cm , 68 2

The micro- or nano-structured mold used for polymer embossing typically must be coated with an anti-adhesion material to reduce its interaction with the embossing. The mold is typically made by nickel sulphamate electroforming. For the anti-adhesion coating to adhere to the mold, the nickel mold surface must be clean and preferably unoxidized or possess reactive groups suitable for covalent bonding with the anti-adhesion coating. The effectiveness of plasma cleaning using mixtures of oxygen (O2) and tetrafluoromethane (CF4) with varying ratios versus liquid-only cleaning was investigated. To simulate the nickel mold, Ni200 alloy was used. Plasma treatment using mixtures of O2 and CF4 was found to be more effective in cleaning the Ni200 surface than liquid-only cleaning or pure O2 or pure CF4 plasma treatment. Using a 1 : 1 O2 /CF4 mixture plasma, the contact angles of water, glycerol and diiodomethane on Ni200 were the lowest and the calculated surface energy was the highest among the investigated treatme...

In order to fabricate good quality ferroelectric thin films, PbZrxTi(1-x)O3 (PZT) and SrBi2Ta2O9 (SBT) films were fabricated on SiO2/Si(100) substrates and on Pt/Ti/SiO2/Si(100) substrates by pulsed laser excimer deposition (PLD). X-ray diffraction, Rutherford backscattering analysis, and atomic force microscopy were used to characterize the structural properties of the samples, which were post-annealed at different temperatures. The results showed that the PZT and SBT films fabricated on Pt/Ti/SiO2/Si(100) substrates and annealed at 700 degreesC exhibited optimum properties. (C) 2002 Elsevier Science B.V. All rights reserved.

Conductive nitrogen doped diamond-like carbon (N-DLC) film electrodes were used to investigate the possibility of detecting heavy metals such as lead, copper and cadmium by differential pulse anodic stripping voltammetry (DPASV) in the absence of mercury film. The preconcentration conditions (deposition potential, deposition time) and solution pH were optimized for the determination of lead in aqueous solution. A linear dependence of lead stripping current peak within the concentration (5 10 7 to 2 10 6 MP b 2 ) and deposition time (30 to 300 s at 1.00 V vs. SCE) was obtained. A multi-elemental analysis (Pb 2 ,C d 2 and Cu 2 ) illustrated that the N-DLC film electrode provided a significant stripping response for determination of multi-metals simultaneously. The present novel electrode showed great promise for the analysis of heavy metals.

The conductive nitrogen-doped diamond-like carbon film (N-DLC) of about 0.14 m in thickness was deposited on highly conductive silicon wafer (111) with DC magnetron sputtering system. The electrochemical characteristics of the film have been studied with cyclic voltammetry (CV). The N-DLC film electrodes compare very favorably with conventional carbon based electrodes such as glassy carbon. The N-DLC film electrode exhibits a low double-layer capacitance, a large electrochemical potential window, and a relatively high electrochemical activity toward ferricyanide reduction. In addition, the electrode exhibits catalytic activity for Cl2/Cl as well as durability to high anodic potential, and a high signal for the trace analysis of Pb 2 . These characteristics demonstrate great promise of the N-DLC film as a novel electrode material for electrochemical analysis.

Nanometer-scale bubbles (nanobubbles) have been produced by a special method on solid surfaces. The atomic force microscope used to detect these nanobubbles showed that they can be seen on liquid/graphite and liquid/mica interfaces. The conformation of the bubbles was influenced by the atomic steps of the graphite substrate. In addition, shadows found around the bubbles were attributed to the interactions between a bubble adhered to the tip and the bubbles on the surface.

Tetrahedral amorphous carbon (ta-C) films which contained aluminum element were fabricated by filtered cathodic vacuum arc (FCVA) method. The tribological characteristics of the ta-C films were investigated with ball-on-disk tribometer. The increment of aluminum in the ta-C film leads to an increase of sp2 carbon bonding and a decrease of sp3 fraction in the film. The roughness of the films was measured with atomic force microscope, and the hardness and Young's modulus of the films were measured with nanoindentation. The results showed that the film hardness and Young's modulus dropped with the increase of Al content in the films. The results have been interpreted with respect to the change of sp 3 and sp 2 fractions in the ta-C:Al films.

Graphite/PEEK laminates were treated by argon plasma followed by air aging and then photografting of α- glycidyl ω- acrylate bisphenol A(GABA) to improve their adhesion characteristics. The effects of plasma time and power and photografting time on the epoxy bonded single lap shear joints between graphite/PEEK laminates were investigated. An optimum photografting time was found at which the single lap shear strength was optimized to 37 MPa compared to 28 MPa and 7 MPa obtained with air-aged argon plasma activated and pristine samples, respectively. Argon plasma treatment followed by air aging of graphite/PEEK laminate introduces surface peroxides and hydroperoxides and these when cleaved with ultraviolet (UV) light in the presence of the GABA monomer results in covalent grafting of the latter to PEEK/graphite laminate surface. The epoxy functionality of the GABA monomer then reacts with the epoxy adhesive. X-ray photoelectron spectroscopy (XPS) confirms the appearance of surface peroxides and hydroperoxid...

Textured Ca modified (Pb,La)TiO 3 (PLCT) films were deposited on Pt/Ti/SiO 2 /Si substrates using a metal-organic decomposition (MOD) process. The microstructure of the PLCT thin film was investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM). Electric properties were measured using the Pt/PLCT/Pt capacitor structure. The PLCT films exhibit good ferroelectric and dielectric properties.

Pb(Zr0.48Ti0.52)O-3 thin films at 20% excess Pb were synthesized on Pt/Ti/SiO2/Si(100) substrates at different annealing temperatures by a metal-organic decomposition process. The microstructure of the PZT films was investigated by x-ray diffraction and atomic force microscopy. The composition of the films was characterized by Rutherford Backscattering Spectroscopy (RBS). These results showed that The PZT films have perovskite phase coexisted with PbO2 phase. The PbO2 phase mainly was formed by excess Pb which congregate at boundaries of crystalline grains during the annealing process and may be absorbed part of oxygen ion at normal sites, thus leading to an increase of oxygen vacancies in the PZT film. PbO2 phase and oxygen vacancies act as pinning centres, which has an effect on the ferroelectric domain switching. This eventually resulted in an increase of fatigue rate in PZT films. (C) 2001 Kluwer Academic Publishers.

Ferroelectric samples with Au/PbTiO 3 /YBa 2 Cu 3 O 7− δ (Au/PTO/YBCO) structures have been grown on SrTiO 3 (STO) substrate. The X-ray diffraction, the capacitance–voltage, and the hysteresis loop methods were used to investigate the samples' structure and ferroelectric properties. The results show that the ferroelectric coercive fields drifted towards positive voltage, and the drift is attributed to the stress at the interfaces of the Au/PTO and the PTO/YBCO.

Total dose radiation effects on Au/PbTiO 3 /YBa 2 Cu 3 O 7− δ (YBCO) capacitors fabricated by pulsed excimer laser deposition (PLD) on SrTiO 3 substrates have been investigated. Capacitance–voltage characteristics and the retained polarization property of the capacitors have been measured before and after γ-ray irradiation. The +4 and 0 V bias was applied across the capacitors during the irradiation. The results showed that with the increment of the total dose, the retained polarization, dielectric constant and the coercive field decreased. The results have been interpreted by radiation-induced positive charges and a defect trap model.

In order to study total dose radiation effects of PbZrxTi1-xO3 (PZT) film made with the pulsed excimer laser deposition (PLD) technique, hysteresis loops and capacitance-voltage (C-V) curves of PZT film capacitors have been measured before and after gamma-ray irradiation. The results show that, in a range of 0-2 x 10(5) Gy (Si), with increasing total dose, the remanent polarization 2P(r) increased while dielectric constant epsilon decreased. This can be explained by charges trapped by some defects during irradiation.

Pt-coated silicon substrates with strong (111) Pt texture were annealed in an oxidizing atmosphere at various temperatures. Dependence of the microstructure and morphology on oxygen partial pressure for SBLN films prepared by pulsed laser deposition were investigated by using X-ray diffraction and atomic force microscopy. The grain size and growth habits of SBLN films were influenced by oxygen partial pressure. As oxygen pressure increases at 10 Pa, nucleation and grains growth of the SBLN films were mainly influenced by the Pt grains of substrate. (100) and (310) texture growth of the SBLN film was revealed, and the film had good e(f) properties.

PbZT(0.52)Ti(0.48)O(3) (PZT)/YBa2Cu3O7-delta (YBCO) structures were fabricated on LaAlO3 and Y2O3-stabilized ZrO2 (YSZ) substrates by a pulsed-excimer-laser deposition method. The total dose effects on the Au/PZT/YBCO ferroelectric capacitors were considered by measuring the capacitance-voltage (C-V) characteristics and the retained polarization properties of the capacitor before and after gamma-ray irradiation. The results show that, with an increase of irradiation dose, for a ferroelectric capacitor which was fabricated on a LaAlO3 substrate, the retained polarization Delta P and the dielectric constant epsilon decreased, but the absolute value of the negative and positive coercive fields increased. For a ferroelectric capacitor which was fabricated on a YSZ substrate, Delta P and epsilon also decreased while the coercive fields drifted towards the positive voltage direction. All these facts are due to the effect of charges trapped by defects in the PZT layer and the interface of the capacitor during irradiation.

We firstly report the successful deposition of highly oriented Pb(Zr0.52Ti0.48)O3 (PZT) ferroelectric thin films on diamond substrates by a simple sol–gel process. The PZT thin films exhibited good surface morphological, structural and electrical characteristics. The electrical measurements were conducted on PZT films in metal–ferroelectric–metal (MFM) capacitor configuration. The typical remanent polarization and coercive electric field values were 5.1 μC/cm2 and 70.0 kV/cm, respectively, at an applied electric field of 300 kV/cm. The low leakage current of 10−8 A/cm2 was found at an applied electric field of 120 kV/cm.

PbZr0.52Ti0.48O3/YBa2Cu3O7−δ (PZT/YBCO) thin films have been fabricated on Y2O3 stabilized zirconate (YSZ) substrates by a pulsed excimer laser deposition (PLD) method. In order to investigate total dose radiation effects on the Au/PZT/YBCO ferroelectric capacitor, the capacitance–voltage (C–V) curves and the retained polarization property of the capacitor have been measured before and after γ-ray irradiation. The results showed that, with an increased total dose, the retained polarization and the dielectric constant decreased, but the coercive field drifted towards positive voltage direction. This is caused by charges trapped by defects in the PZT capacitor during irradiation.

PbZr 0.52 Ti 0.48 O 3 /YBa 2 Cu 3 O 7-δ (PZT/YBCO) thin films have been fabricated on LaAlO 3 substrate by the pulsed laser excimer deposition method. In order to investigate total dose radiation effects by 60 Co γ-irradiation on the Au/PZT/YBCO ferroelectric capacitor, the capacitance voltage (C V) and the retained polarization properties of the capacitor were measured before and after γ-ray irradiation The results showed that. with the increment of the total dose, the retained polarization (ΔP) and the dielectric constant (e) decreased, but the absolute value of the negative and positive coercitive fields increased. It is due to the effect of charges trapped by defects in the PZT capacitor during irradiation.

(PTO/YBCO) and (PZT/ YBCO) structures were fabricated on and substrates by the pulsed excimer laser deposition (PLD) method, respectively. In order to investigate total dose radiation effects on the Au/PTO/YBCO and Au/PZT/YBCO ferroelectric (FE) capacitors, the capacitance-voltage (C-V) and the retained polarization properties of the capacitor were measured before and after -ray irradiation. The results showed that, with the increment of the dose, the retained polarization and the dielectric constant of the FE capacitors decreased; but the absolute value of the negative and positive coercive fields of the PZT capacitor increased while that of the PTO capacitor decreased. The results have been interpreted by radiation-induced positive charges and the defect trap model.

ions with different energies and doses were implanted into SIMOX (separated by implantation of oxygen) materials to improve their irradiation hardness characteristics. Capacitors were fabricated on the SIMOX material after removing the top silicon layer. The high-frequency C-V characteristics of the capacitors after irradiation with -rays were investigated. It is found that the process of implantation can effectively improve the total-dose irradiation hardness of the buried oxide (BOX) layer of the SIMOX materials. In addition, with the change of dose and energy of the implantation, the distribution of F in the SIMOX material was also changed; in particular, for the dose of and 90 keV implantation, a nearly uniform fluorine doping is produced in the BOX layer upon annealing.

Gettering of Cu impurities to He-implantation induced cavities in separation by implantation of oxygen (SIMOX) materials has been investigated by means of cross-sectional transmission electron microscopy and secondary ion mass spectroscopy. The cavities were introduced beneath the buried oxide layer (BOX) in SIMOX substrates by He+ implantation (9×1016/cm2, 60 keV) and subsequent annealing. The results indicate that these cavities are strong gettering sites for Cu impurities which have been implanted into the top Si layer of SIMOX. After a 1000°C annealing, 80% of the initially implanted Cu impurities in the top layer have diffused through the buried oxide layer to be captured by the cavities. The gettering effect of these He-induced cavities is much stronger than the damage region beside the BOX. The buried oxide in SIMOX does not appear to prevent the movement of Cu at 1000°C. He+ implantation-induced cavity has been demonstrated to be an attractive method to remove Cu impurities away from the top Si layer in SIMOX wafers.

UV embossing combined with focused ion beam lithography (FIB) and soft lithography is demonstrated to be a viable method for quick and accessible three-dimensional large-area sub-micrometer patterning of biocompatible films. FIB lithography of titanium nitride thin film is also demonstrated to produce a very smooth surface suitable for nanopatterning.

Multilayer ferroelectric and ferromagnetic thin films were fabricated with the following composition and structure: La0.67Sr0.33MnOx/(Pb, La)(Ca, Ti)O3 (LSMO/PLCT) and (Pb, La)(Ca, Ti)O3/La0.67Sr0.33MnOx (PLCT/LSMO), with an intention of creating a device of new concept. The films were fabricated using metalorganic deposition. The LSMO/PLCT structured films exhibit the ferroelectric properties while the PLCT/LSMO structured films exhibit the ferromagnetic properties. Compared with the PLCT/Pt structure, the capacitance-frequency and tan δ-frequency properties of the LSMO/PLCT structure are degraded. The magnetoresistance of the PLCT/LSMO structure was measured and the results show that the metal-insulator transition temperature is lower than that of the LSMO/SiO2/Si structure. Furthermore, the magnetoresistance at 77 K and at the transition temperature for the PLCT/LSMO structure is higher than that of the LSMO/SiO2/Si structure. These effects can be explained by the piezoelectricity of the PLCT film depo...

The fabrication of very-small-aperture lasers is demonstrated, and their performance is analyzed. Because of strong optical feedback caused by a gold film on the front facet of the laser, its behavior changes: The threshold current decreases, the density of light inside the laser diode and the redshift effect of the spectra are enhanced, and the laser diode's lifetime is shorter than that of common laser diodes with large driving current. (c) 2005 Optical Society of America

The very high aspect ratio (14) and deep (132 μm) channels of an UV-embossed polymeric microstructured surface were successfully metallized by electroless nickel plating. A submicron conformal and highly adherent nickel coating was uniformly deposited on all the hydrophobic silicone-enriched surfaces of the channels. The nickel surface layer acts as a diffusion barrier and also allows for easy subsequent chemical modification by chemical grafting, electroplating, or electropolymerization for diverse applications in micromolding, microfluidics, sensors, microreactors, biomedical devices, and so forth. Hence, electroless nickel plating combined with UV embossing allows easy fabrication of high aspect ratio metallized polymeric microstructures with tailored surfaces.

Silicon mold fabricated with Focused Ion Beam lithography (FIB) was used to make silicone elastomer molds. The silicon mold is composed of lattice of holes which the diameter and depth are about 200 nm and 60 nm, respectively. The silicone elastomer material was then used to replicate slavery mold. Our study show the replication process with the elastomer mold had been performed successfully and the diameter of humps on the elastomer mold is near to that of holes on the master mold. But the height of humps in the elastomer mold is only 42 nm and it is different from the depth of holes in the master mold.© (2004) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A near-field scanning optical microscopy (NSOM) system employing a very-small-aperture laser (VSAL) as an active probe is reported in this Letter. The VSAL in our experiment has an aperture size of 300nm×300nm and a near-field spot size of about 600nm. The resolution of the NSOM system with the VSAL can reach about 600nm, and even 400nm. Considering the high output power of the VSAL, such a NSOM system is a potentially useful tool for nanodetection, data storage, nanolithography, and nanobiology.

In order to investigate the total dose radiation effects of ferroelectric (FE) capacitors, Pt/PbZr0.52Ti0.48O3/Pt (Pt/PZT/Pt) and Au/PbTiO3/YBa2Cu3O7-δ(YBCO) capacitors were fabricated by pulsed excimer laser deposition (PLD) on Si(100) and SrTiO3(001) substrates, respectively. The capacitance-voltage (C-V) curve and hysteresis loops properties of the capacitors were measured before and after γ-ray irradiation. The results show that, with the increment of the total dose, the remanent polarization and the coercive field of the PZT capacitors did not decrease, but increased while the dielectric constantεdecreased; the degradation of theεof the PbTiO3capacitors is similar to that of the PZT capacitors, but the remanent polarization and the coercive field decreased gradually. The results have been interpreted by radiation-induced positive charges and the traps of defects theory.