Photoelectric Property of Polyaniline Doped with Organic Sulphonic Acid

１ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｈｅｃｏｎｄｕｃｔｉｖｅｐｏｌｙｍｅｒ,ｐｏｌｙａｎｉｌｉｎｅｉｓｏｎｅｏｆｔｈｅｒｅｓｅａｒｃｈｉｎｇｈｏｔ－ｐｏｉｎｔｓｆｏｒｉｔｓｖａｒｉｏｕｓｓｔｒｕｃｔｕｒｅ,ｓｐｅｃｉｆｉｃｄｏｐｉｎｇｍｅｃｈａｎｉｓｍ,...     

Influence on Conductivity of Polyparaphenylene by Chemical Doping and Ion Implantation

１ＩｎｔｒｏｄｕｃｔｉｏｎＡｓａｎｅｗｋｉｎｄｏｆｃｏｎｄｕｃｔｉｎｇｐｏｌｙｍｅｒ,ｐｏｌｙｐａｒａｐｈｅｎｙｌｅｎｅ（ＰＰＰ）ｉｓｔｈｅｐｏｉｎｔｏｆａｔｅｎｔｉｏｎｆｏｒｍａｎｙｓｃｈｏｌａｒｓｄｕｅｔｏｉｔｓｌｏｗｃｏｓｔ,ｓｉｍｐｌｅｓｙｎ...     

Preparation,Structure and DC Conductivity of Organic Semiconductor PANI—C4H6O6

A new organic semiconductor tartaric acid doped salt of emeraldine polyaniline(PANI-C4H6O6)has been obtained by the method of oxidative polymerization of monomeric aniline with ammonium persulfate in acidic solution.The structure was characterized by Fourier Transform Infrared technique(FTIR) and X-ray diffraction(XRD).The temperature dependence dc conductivity δdc(T)shows a semiconductor behavior and follows the quasi one dimensional variable range hopping(Q1D-VRH)model.Data on δdc(T) are also discussed.     

Enhanced Efficiency and Durability of Organic Electroluminescent Devices by Doping in Emitting Layer

Remarkable improvement in efficiency and stability has been observed in a doped organic electroluminescence device, which consists of a hole-transport layer, an electron-transport layer and a luminescent layer. The hole-transport layer is a N,N'-bis(3-methyphenyl)-N,N'-diphenylbenzidine film. The doped emitting layer consists of 8-(quinolinolate)-aluminum as the host and rubrene as the emission dopant. The doped device demonstrated a brightness in excess of 40 000 cd/m 2 and the maximum external quantum efficiency of 3.4%, which is about six times and four times respectively greater than those of the undoped device. For no packaged deviced, a luminance half-life on the order of about 230 h has been achieved under a constant current density of 15 mA/cm 2, starting at 500 cd/m 2 at the room temperature.     

Efficient Organic Multi—quantum Well Electroluminescent Devices Using Aluminum as Cathodes

Organic green light emitting devices(LEDs)with multi-quantum well(MQW)structure were fabricated.Aromatic diamine(TPD)was used as holetransporting layer and potential barrier layer;Tris(8-hydroxyquinoline)aluminunum(Alq3)was acted as electron-transporting emitter and MQW green emitter.Airstable aluinum(Al)was used as electron-injection contact.The influence of the thickness of potential barrier layer and the number of quantum well on the electroluminescent(EL)efficiencies of the devices was investigated.The organic LEDs with two quantum wells showed enhanced EL efficiencies.Maximum external quantum efficiency and brightness were 1.04% and 7000cd/m^2,respectively.     

Optical Fiber Displacement Sensor with Ultra—high Resolution

A low fineness fiber optic Fabry-Perot interferometric displacement sensor has been developed and tested.A 0.005 nm displacement resolution is obtained by using He-Ne laser with a high performance,photodetectors with low nois,low drift operational amplifiers,6-pole Butterworth filters and perfect digital signal processing circuits.     

Fiber Grating Ring Laser in All Optical Communication System

Erbium fiber grating ring laser(EFRL)witn an integrated travelling wave and low polarization mode noise is reported.Through modulated experiment of a successful 2.488Gb/s RZ data,it is shown that the EFRL is a promising alternative to DFB lasers for high-speed transmission applications.     

Carrier Transport Properties in the Doped Micro—crystalline Silicon Films

Doped micro-crystalline silicon films are deposited at temperatures as low as 400 ℃ by the catalytic chemical vapor deposition method using a silane and hydrogen gas mixture. Electrical properties such as the carrier concentration and the Hall mobility are investigated for various measuring temperatures. It is found that the grains of micro-crystalline silicon are preferentially oriented along the (220) direction , and that the Hall mobility is larger than 8 cm 2·V -1 ·s -1 , the carrier concentration is about 1×10 17 cm -1 ～1×10 19 cm -3 at room temperature.     

Analysis of Optical Signal Transmission Characteristics in AWG Multi/Demultiplexer with Electromagnetic Field Theory

Based on the electromagnetic field theory, the optical signal transmission characteristics in input/output waveguides, slab waveguides and arrayed waveguides of the arrayed waveguide grating (AWG) multi/demultiplexer are analyzed. The relationship between the physical parameters such as geometry sizes and relative refractive index in AWG multi/demultiplexer and the optical signal transmission characteristics are discussed. This theoretical study can be used for optimizing the design and improving the performance of the AWG multi/demultiplexer.     

Simulation and Fabrication of Sampled FIber Bragg Grating

The calculation principle of sampled FBG,which is called transfer matrix method, is analyzed and the simulation software is designed.The sampled FBG is simulated with the software we designed and is fabricated by ourselves.The experiment result fits well with the simulated one.It is concluded that to improve the refractive modulation index is an effective way to fabricate a sampled FBG with high-reflectivity.     

(Al x Ga 1- x ) y In 1- y P Films and Its Optical Constants on the Surface

１ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｑｕａｒｔｅｒｎａｒｙｓｅｍｉｃｏｎｄｕｃｔｏｒＡｌＧａＩｎＰ,ｗｈｉｃｈａｒｅｍａｔｃｈｅｄｗｉｔｈｔｈｅＧａＡｓｌａｔｉｃｅ,ｈａｓｔｈｅｗｉｄｅｓｔｄｉｒｅｃｔｂａｎｄｇａｐ．Ｉｔｓｌｕｍｉｎｅｓｃｅｎｃｅｉｓｒ...     

New Fluoroptic Thermometer with Optical Fiber

A new optical fiber fluoroptic thermometer based on the temperature-fluoroptic characteristic of fluoroptic materials is presented.The ratio technique of intensities of fluorescent emission lines of certain rare earth phosphors is used,making the measurement of temperatures of the system to 0.5℃ precision.The characteristics of thermometer are discussed and the experiment results of temperature are given.     

Comparison of GexSi1—x Grown by UHV／CVD from Si2H6／GeH4 and SiH4／GeH4

Using double crystal X-rays diffraction (DCXRD) and atomic force microscopy (AFM), the results of Ge x Si 1- x grown by UHV/CVD from Si 2H 6 and SiH 4 are analyzed and compared. Adsorbates can migrate to the energy-favoring position due to the slow growth rate from SiH 4. In this case, a Si buffer that isolates the effect of substrate on epilayer could not be grown, which results in a pit penetrating into epilayer and buffer. The FWHM is 0.055° in DCXRD from SiH 4. The presence of diffraction fringes is an indication of an excellent crystalline quality. The roughness of the surface is improved if grown by Si 2H 6; however, the crystal quality of the Ge x Si 1- x material became worse than that from SiH 4 due to much larger growth rate from Si 2H 6. The content of Ge is obtained from DCXRD, which indicates the growth rate from Si 2H 6 is largest, then GeH 4, and that from SiH 4 is least.     

Maximum and Continuous Wavelength Tuning Ranges of a Grating External—cavity Laser Diode

The wavelength tuning rages of a grating external-cavity laser diode(ECLD)have been studied by the equivalent avity method.The maximum tuning range(MTR)and the continuous tunding range(CTR),which are related to the maximum and the minimum threshold carrier densities,are deduced from the threshold condition.We define a ratio of the CTR to the MRT.This ratio is only determined by the reflectivities of the external and internal facets of the ECLD.The analysis shows that there is an appropriate combination of the external and internalcavity reflectivites to obtain a given CTR in the design of an ECLD.     

Irradiation Defects in Silicon Crystal

The application of irradiation in silicon crystal is introduced.The defects caused by irradiation are reviewed and some major ways of studying defects in irradiated silicon are summarized.Furthermore the problems in the investigation of irradiated silicon are discussed as well as its properties.     

Spectral Properties of Yellow Fluorescent Powder for White LEDs

Much attention has been paid to white LEDs because of their potential applications in the illumination.The doping of rate earth ions plays an important role in the optical properties of yellow fluorescent powder.And mainly aiming to raise the intensity and the luminous rate of the white LEDs and by photoluminescence and electroluminescence,the luminescence spectrum of yellow fluorescent powder bought from different places is measured.Furthermore,the luminous intensity in the normal direction and the angle distribution of half maximum power for the white LEDs packed with cylindrical φ5 epoxy on the same blue GaN chips are also measured under the same manufacture conditions.The results show that the yellow fluorescent powder bought from China mainland has higher optical output rate than that bought from China Taiwan and hence is more suitable to fabricate the white LEDs for practical use.     

Photoluminescence Spectra of Disordered and Ordered Ga 0.52 In 0.48 P

Temperature-dependence and excitation-intensity-dependence of photoluminescence spectra for both disordered and ordered Ga0.52 In0.48P are measured.The disordered sample is charactierized by its single pcak photoluminescence spectrum which is excitation-intensity.independent and has different activation energy at different temperature region.The ordered sample shows double peaks,the intensity of the high-energy peak has an anomalous increase firstly and quenches afterwards.The relative henomena are reasonably explained in terms of lattice ordering and orientation superlattice model.     

Elimination of Zig—zag Defects in Surface—stabilized Ferroelectric Liquid Crystal Cells

The elimination of zig-zag defects in polyimide-coated surface-stabilized ferroelectric liquied crystal(SSFLC)cells is carried out by appliying a low-frequency electric field.It has been achieved when the thickness of SSFLC cell is 3μm.The optical spectral transmittance measurement confirmed that there is no change of layer structure,and the memory capability was not improved.The different effects of low-frequency electric field applied on the different thickness FLC cells have been observed.and experimental results were presented.     

Deposition of Silicon Nitride Films by Silane Hydrazine Process

A new catalytic chemical vapor process for depositing silicon nitride films using silane hydrazine gaseous mixture is described.This system can be useful at a temperature of lower than 400 ℃.The catalytic process gives more rapid deposition rate than 10nm/min.The atomic composition ration.N/Si,which is evaluated by Rutherfold backattering method is about 1.4under a given experimental conditions more than the stoiciometric value of 1.33 in Si3N4.The infrared transmission spectra show a large dip at 850cm^-1 due to Si-N bonds and no clear dip due to Si-O bonds.High N-H bond density is the evidence that the deposition mechanism is limited by N-N bond breaking of the hydrazine.The H contents,evaluated from Si-H and N-H bonds in the infrared absorption spectra,and the deposition rate are measured as a function of the substrate temperature.In addition some film properties such as the reistivity and the breakdown electric field are presented.     

Low Distortion 1.31μm AlGaInAs／InP MQW DFB Laser Module for CATV Systems

１ＩｎｔｒｏｄｕｃｔｉｏｎＬｏｎｇｈａｕｌｏｐｔｉｃａｌｆｉｂｅｒｃｏｍｍｕｎｉｃａｔｉｏｎ,ｍｕｌｔｉ－ｃｈａｎｎｅｌｔｒａｎｓｍｉｓｉｏｎａｎｄｏｐｔｉｃａｌｆｉｂｅｒＣＡＴＶｓｙｓｔｅｍｒｅｑｕｉｒｅ１．３１μｍａｎｄ１．５５μｍＤＦＢｌａｓｅ...