Investigation of Electrical and Structural Properties of Ag/TiO2/n-InP/Au Schottky Diodes with Different Thickness TiO2 Interface

Silicon - In this study, structural and electrical properties of Ag/TiO2/n-InP/Au Schottky barrier diodes, constructed with sputtering method on n-InP wafer, are investigated. Particle size, d-...     

Influence of Annealing Temperature on Structural and dc Electrical Properties of SnO2 Thin Films for Schottky Barrier Diodes

This paper reports about the influence of annealing temperature on the structural, morphological, optical and electrical properties of SnO₂ thin films prepared by the spin-coating method. The structural analysis reveals the presence of rutile SnO₂ with tetragonal structure and its defects are reduced in higher annealing temperatures. SEM images show that the size of the grains was improved due to increase in annealing temperature. From UV-visible analysis, band gap energy (E_g), refractive index (n), and extinction coefficient (k) are estimated. The band gap energy increases from 3.46 to 3.54 eV with annealing temperatures. dc analysis shows that the Arrhenius conduction mechanism has a profound influence on the electrical conductivity and varies in the range 1.08–6.80 × 10^− 8(Ω cm)^− 1 with annealing temperature. The Al/n-SnO₂/p-Si Schottky barrier diode parameters such as ideality factor (n), barrier height (4Φ_B), leakage current (I₀) and series resistance (R_s) were studied by the I-V method as a function of annealing temperature as per the Thermionic Emission method (TE). The barrier height varies from 0.84 to 0.73 eV and the device ideality has improved at higher annealing temperature.

     

Effect of Annealing Temperature on Structural and Electrical Properties of Al/ZrO2/p-Si MIS Schottky Diodes

Silicon - The structural and electrical properties of Al/ZrO2/p-Si Schottky barrier diodes (SBDs) have been investigated at different annealing temperatures (300, 400, 500 and 600 °C). X-ray...     

乙二醇为还原剂制备铁掺杂二氧化锰及其电容特性研究

通过简单的液相沉淀法制备出棉絮状二氧化锰纳米颗粒,采用掺杂铁离子的方式对二氧化锰进行改性.热重曲线显示,掺杂Fe之后增加了产物中结合水的含量.由SEM可知,加入铁离子之后并没有改变二氧化锰的表面形貌,XRD与面扫结果表明铁离子以均一的方式掺杂到了二氧化锰中.循环伏安与恒电流充放电测试了材料的电化学性能,结果显示当掺杂量为2％时材料具有最好的电化学性能,担载量为3 mg·cm-2的情况下,放电比容量高达347.0 F·g-1,循环1000圈后容量的保持率为81.4％.     

Sintering and Properties of Titanium Diboride Made from Powder Synthesized in a Plasma-Arc Heater

The pressureless sintering to near theoretical density of high-purity titanium diboride powder, produced in a plasma arc from halogen vapor reactants, is described. Physical and mechanical property measurements between 25° and 1400°C are reported for materials densified at T=1800° to 2275°C. Titanium diboride exhibits several unusual and interesting properties, which include high electronic conductivity, a large positive strength-vs-temperature coefficient, and an intrinsic resistance to high-temperature slow crack growth (negative N ) Property trends are explained in terms of microstructural development and residual grain-boundary stresses.     

羧甲基甲壳素助留助滤剂的制备及性能

以甲壳素(CH)为原料、氯乙酸钠为醚化剂,合成了不同取代度(DS)的水溶性羧甲基甲壳素CCHx(下标x表示取代度,x=0.4,0.5和0.6),并用IR、XRD对其结构进行了表征。结果表明:羧甲基基团成功引入到了CH骨架上,并且破坏了结晶区。考察了CCH对纸浆的助留助滤性能,结果表明:CCH的DS越大,其助留助滤效果越好。当CCH0.6加入量为0.5%(以纸浆干重计,下同)时,留着率由没添加CCH0.6时的35%提升至70%,打浆度由33.0°SR下降至23.0°SR。进一步加入0.5%(以纸浆干重计,下同)的聚合氯化铝(PAC),与CCH0.6构建二元体系,并对其助留助滤性能进行了测试,结果表明:CCH0.6/PAC二元体系的留着率由CCH0.6单独体系的70%提升至80%,打浆度由23.0°SR轻微下降到21.5°SR。     

新型含噻吩类衍生物的合成与光谱特性

在四(三苯基膦)钯(Pd(PPh3)4催化作用下,通过催化偶合法可合成5,8-二噻基-萘基喹喔啉(DThQx(ace))和3,6-二噻基-哒嗪(DThPD)两种新型噻吩衍生物,同时也可合成了4,7-二噻基-2,1,3-苯并噻二唑(DThB)和1,4-二噻基-苯(DThPh),上述化合物产率分别为75%,78%,82%和67%。用红外光谱、核磁共振谱、元素分析等方法进行了表征,并对噻吩与不同芳香环构成的衍生物的紫外-可见吸收光谱和荧光光谱进行了对比研究。这四种化合物的紫外-可见吸收光谱中分别在435,336,446,325 nm处有最大吸收波长。其中DThQx(ace)、DThB和DThPh的荧光光谱中分别在564,568 nm和384 nm处观察到荧光,而DThPD无荧光。     

新型咔唑衍生物的合成及发光性能研究

基于螺二芴的大位阻结构和咔唑的高三线态能级,设计了一种在咔唑的3、4和5、6位并入两个高位阻的螺二芴结构,以4,4′-二甲基联苯为起始原料,经过硝化反应、Bucherer反应、偶联反应、卤化、Suzuki偶联反应和关环等反应成功制备了咔唑衍生物CzSF2,产物结构经过1 HNMR、13 CNMR、MS确证.其在二氯甲烷...     

Fabrication and Electrical Properties of Lead Zirconate Titanate Thick Films on Si Substrate by Using Lanthanum Nickelate Buffer Layer

Lead zirconate titanate PbZr_0.53Ti_0.47O₃ (PZT) thick films have been deposited on silicon substrate by modified metallorganic decomposition process. Crack-free PZT films of 8 μm thickness can be obtained by using lanthanum nickelate LaNiO₃ (LNO) as buffer layer. The greater LNO thickness, the greater thickness of crack-free PZT can be obtained. The X-ray diffraction measurements show the films exhibit a single perovskite phase with (110) preferred orientation. SEM measurements showed the PZT thick films have a columnar structure with grain size about 60–200 nm. The thickness dependence of ferroelectric, dielectric, and piezoelectric properties of PZT thick films have been characterized over the thickness range of 1–8 μm. For PZT with thickness of 8 μm, P _r and E _c are 30 μC/cm² and 35 kV/cm, and dielectric constant and dielectric loss are 1030 and 0.031, respectively. The piezoelectric coefficient ( d ₃₃) of PZT with 8 μm thickness is obtained to be 77 pm/V. PZT thick films on LNO-coated Si substrate are potential for MEMS applications.     

Analysis of Double Gaussian Distribution at the Interface of Ni/Ta2O5/P-Si Schottky Barrier Diodes Using Temperature Dependent Current-Voltage (I-V) Measurements

Silicon - The electrical properties have been investigated for Ni/Ta2O5/p-Si Metal/insulator/semiconductor SBD in the temperature regime 175–400 K. The electrical parameters were...     

Frequency and Temperature Dependence of Dielectric Properties of Au/Polyvinyl Alcohol (Co,Ni-Doped)/n-Si Schottky Diodes

The dielectric properties and AC conductivity of Au/polyvinyl alcohol (Co, Ni-doped)/n-Si Schottky diodes (SDs) were investigated in the frequency range 1 kHz–1 MHz and in the temperature range 80–400 K. The frequency and temperature dependence of dielectric constant (?′), dielectric loss (?″), loss tangent (tan δ), AC electrical conductivity (σ _ac ) and the real and imaginary parts of the electric modulus (M′ and M″) were found to be a strong function of frequency and temperature. The values of ?′, ?″ and tan δ decrease with increasing frequency, while they increase with increasing temperature, especially above 275 K. The values of σ _ac increase with both increasing frequency and temperature. Such temperature-related behavior of σ _ac can be attributed to the high mobility of free charges at high temperature. Electric modulus formalism was also analyzed to obtain experimental dielectric data. The values of M′ and M″ increase with increasing frequency, while they decrease with increasing temperature. The interfacial polarization, which more easily occurs at low frequencies and high temperatures, consequently contributes to the improvement of the dielectric properties of SDs.     

两种新型苯并噁嗪酮衍生化合物的合成及光学性能研究

以5-氯邻氨基苯甲酸和对甲氧基苯磺酰氯为原料缩合合成含有分子内氢键的6-氯-2-[5-氯-2-(4-对甲氧基苯磺酰胺基)]苯基-4-苯并噁嗪酮。利用BF3·OEt2氟硼化反应及与邻苯二胺的缩合反应分别制得苯并噁嗪酮的衍生物。利用红外、质谱、核磁(1HNMR、11BNMR、19FNMR)及元素分析等对化合物结构进行了表征,并研究了化合物的光学性能,热稳定性及光稳定性。研究表明,两种衍生化合物均具备超过150 nm的大斯托克斯位移,强荧光发射能力,高荧光量子产率,并且光稳定性明显优于罗丹明6G染料,分解温度甚至达到260℃以上,说明所得化合物是性能良好的光致发光材料。     

碳酸锰制备新工艺及其电化学性能探讨

研究以硫酸锰和碳酸氢铵为原料制备超细碳酸锰,采用正交法优化最佳工艺条件为:表面活性剂的用量为Mn2摩尔数的0.046,碳酸氢铵浓度为1.0 mol/L,硫酸锰的浓度为1.1 mol/L,反应温度60℃,反应时间40 min,碳锰比R(CO2-∶Mn2+)=1.6∶1.0,V(C2H6O)/V(H2O)=1.0∶1.0,pH值为7.0.在此条件下得到的样品为球形碳酸锰,粒径分布均匀,平均粒径为582 nm,属亚微米级,所制备的锰酸锂纽扣电池有较好的电性能.     

Preparation and C3H8/Gas Separation Properties of a Synthesized Single Layer PDMS Membrane

In this paper, a new polydimethylsiloxane (PDMS) membrane was synthesized and its ability for separation of heavier gases from lighter ones was examined. Sorption, diffusion, and permeation of H₂, N₂, O₂, CH₄, CO_2, and C₃H₈ in the synthesized membrane were investigated as a function of pressure at 35°C. PDMS was confirmed to be more permeable to more condensable gases such as C₃H₈. This result was attributed to very high solubility of larger gas molecules in hydrocarbon?based PDMS in spite of their low diffusion coefficients relative to small molecules. The synthesized membrane showed much better gas permeation performance than others reported in the literature. Increasing upstream pressure increased solubility, permeability and diffusion coefficients of C₃H₈, while these values decreased slightly or stayed constant for other gases. Local effective diffusion coefficient of C₃H₈ and CO₂ increased with increasing penetrant concentration which indicated plasticization effect of these gases over the range of penetrant concentration studied. C₃H₈/gas solubility, diffusivity and overall selectivities also increased with increasing feed pressure. Ideal selectivity values of 4, 13, 18, 20, and 36 for C₃H₈ over CO₂, CH₄, H₂, O_2, and N₂, respectively, at upstream pressure of 7 atm, confirmed the outstanding separation performance of the synthesized mebrane.     

Investigations on Characterization and Properties of Al-MoO3 Composites Synthesized Using Powder Metallurgy Technique

Silicon - In this work, Powder Metallurgy (PM) technique was used to synthesize Aluminium based metal matrix composites with various weight percentages (0, 5, 10 & 15) of Molybdenum...     

Optical,Electrical and Photoresponse Properties of Si-based Diodes with NiO-doped TiO2 Film Prepared by Sol-gel Method

Silicon - The Ti1−xO2NixO films (x = 0.0, 0.05, 0.10 and 0.15) with various NiO contents were prepared by sol-gel technique. The prepared films were coated on n-Si substrate by spin coating...