We have fabricated a Top-emitting organic light-emitting device on silicon substrate Delta -doping technique. Using ultrathin quinacridone as emitting layer, the performance of Top-emitting organic light-emitting device is improved obviously. However, when increasing the thickness of the anode, the performance of device is enhanced dramatically. The max power efficiency of device is 5.9 Lm/W at 5 V corresponding to the current efficiency of 9.3 cd/A. The max current efficiency of device is also increases to 11 cd/A at 7 V. (C) 2010 Elsevier B. V. All rights reserved.

Nano-tungsten powder was prepared on the basis of an industrialized production technique, using WO2.72 as the raw materials. The phase, composition, morphology, thermal stability, special surface area and pore structure of the samples were characterized by XRD, EDS, SEM, FESEM, DTA-TG, BET and pore Size Analyzer. The results show that high-quality nano-tungsten powder can be produced by reducing the hydrogen reduction temperature, slowing down the pushing boat speed, reducing the boat charging capacity and increasing hydrogen flow rate.

SiOx∶Er thin films were prepared by RF magnetron reactive sputtering technique using Er2O3 and Si targets.After annealing at different temperatures and time,the samples exhibit photoluminescence peaks at around 1 530,1 542 and 1 555 nm.It is found that annealing can enhance the PL intensity remarkably.The variations of SiOx∶Er thin films photoluminescence with annealing temperatures and annealing time were also studied,and found that when Er2O3∶Si of 1∶1,the temperature of 1 100 ℃,20 min annealing were the best annealing conditions.XRD spectra and optical absorption measurements are performed to investigate the structure of films,therefore,the size of nc-Si is 1.6 nm,the optical band gap Eg of the sample is estimated to be 1.56 eV,indicating that the films are silicon-rich.Finally,three different Er2O3 and Si proportions were studied,the best ratio of the Er2O3∶Si is 1∶3,and the luminescence phenomenon of films was discussed.

Nanocrystalline tungsten carbide(nano-WC) powder was prepared on the basis of the industrialized production equipment.Methods of X-ray diffraction,specific surface area,FESEM,TEM,and laser particle analyzer of dynamic light scattering were applied to test the phase,particle size and its distribution of nano-WC powder.Discussion was made for the testing principle.The results indicate the average particle size of nano-WC is 90 nm and most of the particles are spherical shape,but few are the shape of the polygon.In order to more accurately measure particle size of nano-WC powder,the sample should have good dispersion to avoid aggregation.The shape of nano-WC powder also have important influence on measurement of particle analyzer of dynamic light scattering.

Er/Bi codoped SiO2 thin films were prepared by sol–gel method and spin-on technology with subsequent annealing process. The bismuth silicate crystal phase appeared at low annealing temperature while vanished as annealing temperature exceeded 1000°C, characterized by X-ray diffraction, and Rutherford backscattering measurements well explained the structure change of the films, which was due to the decrease of bismuth concentration. Fine structures of the Er3+-related 1.54μm light emission (line width less than 7nm) at room temperature was observed by photoluminescence (PL) measurement. The PL intensity at 1.54μm reached maximum at 800°C and decreased dramatically at 1000°C. The PL dependent annealing temperature was studied and suggested a clear link with bismuth silicate phase. Excitation spectrum measurements further reveal the role of Bi3+ ions for Er3+ ions near infrared light emission. Through sol–gel method and thermal treatment, Bi3+ ions can provide a perfect environment for Er3+ ion light emission by forming Er–Bi–Si–O complex. Furthermore, energy transfer from Bi3+ ions to Er3+ ions is evidenced and found to be a more efficient way for Er3+ ions near infrared emission. This makes the Bi3+ ions doped material a promising application for future erbium-doped waveguide amplifier and infrared LED.

Nano-WC powders were prepared through fast carbonization for 15 min at 1 050℃using nanotungsten powders and carbon black as raw materials by industrial production technology.The phase,composition, morphology and particle size of nano-WC powders were analyzed by means of XRD,EDS,SEM and FESEM.The results show that the purity of the nano-WC powders was very high.The powders had a small amount of W_2C and free carbon.The particles uniformly distributed,which were spherical,plate and polygonal.And the average particle size was 68.9 nm.

Nano-W powder was produced by industrialized production technology, and the heat treatment of samples was carried out at different temperature. The morphology, phase, content and special surface area, and pore structure of the samples were characterized using SEM, XRD, EDS and automated surface area and pore size analyzer respectively. The lattice changes of the samples after heated treatment were judged by calculating the change rate of lattice, and the growth mechanism of grain and the change of pore structure were explained by measuring its grain size and pore volume. The results indicate that the lattices of nano-W powder after heat treatment have changed into expansion from contraction. With temperature increasing, the specific surface area and pore size decreases, and particle size increases. The grain growth is very rapid at 1200 ℃, and its growth mechanism is explained according to grain boundary migration.

采用射频磁控反应溅射技术和后退火法制备了nc-Ge/SiO2薄膜材料。采用X射线衍射仪（XRD）对薄膜的微结构进行测试,随着退火温度的升高,衍射峰的半高宽减小,表明Ge纳米晶粒的平均尺寸逐渐增大,发现经过1 000℃退火后的薄膜具有三个明显的纳米锗衍射峰。薄膜的傅里叶红外吸收谱表明,随着退火温度的升高,薄膜的红外吸收增强。室温下,测量了不同温度退火下薄膜的光致发光谱,观察到了紫外光、紫光和橙色光。而且不同退火温度的薄膜,其光致发光谱有所不同,理论上着重讨论了紫光和橙光的发光机制。

a-Si/a-SiN_x superlattices of different Si layer thickness were fabricated by RF magnetron sputtering technique.IR,EDS,XRD,absorption,photoluminescence(PL) techniques were used to study the composition,structure and the luminescent properties.The results indicated the absorption edge positions and PL peaks shift with different Si layer thickness.The quantum confinement effects(QCE) was obviously observed.After thermal annealing at 1000℃,the PL peak of the thicker sample was found to shift towards shorter wavelength due to the formed nc-Si particles in a-Si layers.

The nc-Si/SiNx multi-quantum well(MQW)was prepared by RF magnetron sputtering technique and thermal annealing.The sample was tested by low-angle XRD,Raman spectrometry and absorption spectrometry,and its structure and optical properties were studyed.Nonlinear optical properties of nc-Si/SiNx MQW were probed by a Z-Scan Technique.The experimental results show that the nonlinear refractive index of the sample is a negative value and the nonlinear absorption is two-photon absorption.After calculating,it is obtained that χ(3) of the sample is 7.50 10-8esu,the value of nc-Si/SiNx MQW is 4 orders of magnitude higher than that of bulk Silicon.The nonlinear mechanism of the material was discussed.The enhancement of nonlinear refractive index is mainly attributed to the enhancement of quantum confinement.

采用金属有机化学气相淀积(MOCVD)法在InP衬底卜低温生长6个周期的InGaAsP多量子阱薄膜,薄膜对1.06μm激光的小信号透过率为23%.该薄膜兼作Nd:YAG激光器的可饱和吸收体及耦合输出镜,实现1.064 μm激光的被动锁模运转,获得平均脉宽23 ps,能量15 mJ的单脉冲序列.采用射频磁控溅射法在石英衬底上制备4个周期的Si/SiNx多量子阱薄膜,样品在氮气环境下以1000℃退火30 min后,插入Nd:YAG激光器腔内,实现1.064μm激光的被动锁模,获得脉宽30 ps的脉冲序列.多量子阱半导体薄膜作为可饱和吸收体实现激光器的被动锁模具有成本低、设计和制作简单、运转稳定和使用方便的优点.

To solve the question of frequency follow used in induction pyrogenation system and make it work in the optimal condition,a new type all-digital phase-locked loop(ADPLL)induction pyrogenation system was designed.The project bases on field programmable gate array(FPGA) and adopts proportional-integral control.The results of the simulation show that ADPLL can lock the frequency timely and effectively,and it has many advantages such as follow rate rapidness;high precision;strong flexibility and wide-rang frequency width.According to the resonant frequency of the object,the parameters N of 1 /N divider,the parameters K of K-mode counting module and the median n of integral module counter can be adjusted to make ADPLL work in the optimal condition.

E2SiO5 thin films were fabricated on Si substrate by reactive magnetron sputtering method with subsequent annealing treatment. The morphology properties of as-deposited films have been studied by scanning electron microscope. The fraction of erbium is estimated to be 23.5at% based on Rutherford backscattering measurement in as-deposited Er–Si–O film. X-ray diffraction measurement revealed that Er2SiO5 crystalline structure was formed as sample treated at 1100°C for 1h in O2 atmosphere. Through proper thermal treatment, the 1.53μm Er3+-related emission intensity can be enhanced by a factor of 50 with respect to the sample annealed at 800°C. Analysis of pump-power dependence of Er3+ PL intensity indicated that the upconversion phenomenon could be neglected even under a high photon flux of 1021(photons/cm2/sec). Temperature-dependent photoluminescence (PL) of Er2SiO5 was studied and showed a weak thermal quenching factor of 2. Highly efficienct photoluminescence of Er2SiO5 films has been demonstrated with Er3+ concentration of 1022/cm3, and it opens a promising way towards future Si-based light source for Si photonics.

Nanocrystalline tungsten carbide(nano-WC) powder is prepared on the basis of the industrialized production equipment.Methods of X-ray diffraction,specific surface area,SEM,FESEM and TEM are applied to test the phase,particle size and its distribution of nano-WC powder.The results indicate the average particle size of nano-WC is about 90nm and most of the particles are spherical shape.Nano-WC powder is annealed at different temperatures for different time.The grain coarsening mechanism is studied and proved to be according with the classic LSW theory. Furthermore,temperature is an important factor to affect the grain growth of nano-WC and the grain size increases with the high temperature.

Er-doped silicon-rich silicon nitride (SRN) films were deposited on silicon substrate by an RF magnetron reaction sputtering system. After high temperature annealing, the films show intense photoluminescence in both the visible and infrared regions. Besides broad-band luminescence centered at 780 nm which originates from silicon nanocrystals, resolved peaks due to transitions from all high energy levels up to 2H11/2 to the ground state of Er3+ are observed. Raman spectra and HRTEM measurements have been performed to investigate the structure of the films, and possible excitation processes are discussed.

The silicon nitride (ncSi-SiNx) composite films with nanocrystal-Si-particle were prepared by RF magnetron reaction sputtering technique and thermal annealing.The composition,structure and optical band gap of the films were characterized by energy dispersive spectrometer (EDS) and X-ray diffraction(XRD).The nonlinear optical properties of ncSi-SiNx composite films were investigated by using single beam Z-scan technique with a picosecond pulses laser.The measured third-order nonlinear optical refractive index and nonlinear absorption coefficient are enhanced and estimated to be on the order of 10-8 esu and 10-8 m/W respectively.This is due to the quantum confinement effect.

Nanocrystalline tungsten carbide(nano-WC) powder was prepared on the basis of the industrialized production equipment and were annealed at various temperature.Methods of X-ray diffraction,FSEM,TEM,specific surface area,and particle analyzer of dynamic light scattering were applied to test the phase,particle size and its distribution of nano-WC powder.The results indicated temperature was a important factor to affect the grain growth of nano-WC.The grain size increased with the high temperature.The DSC curves of nano-WC powders were measured at difierent heating rates and the activation energy for grain growth of nano-WC was calculated.Then,these experiment phenomena were analyzed and discussed.

Nano-W powder with various grain sizes are successfully produced on the basis of industrialized production technology.The content,morphology and phase of the samples are characterized by using EDS,SEM and XRD,and the lattice parameters and cell volume are worked out.The results indicate that nano-W powder have bcc crystal structure,the shrinkage of lattice has taken place.With the decrease of the grain sizes,the shrinkage rate of the lattice parameters and cell volume increases and the lattice distortion rate is inverse proportional linear relationship to the grain sizes.

Er-doped silicon nitride films were deposited on silicon substrate by RF magnetron reaction sputtering system.After high temperature annealing the films show intense photoluminescence at both visible and infrared region.Resolved luminescence due to the transitions from all high energy levels up to 2H11/2 to the ground states of Er3+ was observed.RBS measurement was performed to investigate the composition of the films,and the mechanics of the photoluminescence was discussed.