Enhanced Work Function of Al-Doped Zinc-Oxide Thin Films by Oxygen Inductively Coupled PlasmaTreatment简

Al-doped zinc-oxide （AZO） thin films treated by oxygen and chlorine inductively coupled plasma （ICP） were compared. Kelvin probe （KP） and X-ray photoelectron spectroscopy （XPS） were employed to characterize the effect of treatment. The results of KP measurement show that the surface work function of AZO thin films can increase up to 5.92 eV after oxygen ICP （O-ICP）＇s treatment, which means that the work function was increased by at least 1.1 eV. However, after the treatment of chlorine ICP （CI-ICP）, the work function increased to 5.44 eV, and the increment was 0.6 eV. And 10 days later, the work function increment was still 0.4 eV after O-ICP＇s treatment, while the work function after Cl-ICP＇s treatment came back to the original value only after 48 hours. The XPS results suggested that the O-ICP treatment was more effective than CI-ICP for enhancing the work function of AZO films, which is well consistent with KP results.     

Construction of Larger Area Density-Uniform Plasma with Collisional Inductively Coupled Plasma Cells

The plasma density and electron temperature of a multi-source plasma system composed of several collisional inductively coupled plasma （ICP） cells were measured by a doubleprobe. The discharges of the ICP cells were shown to be independent of each other. Furthermore, the total plasma density at simultaneous multi-cell discharge was observed to be approximately equal to the summation of the plasma density when the cells discharge separately. Based on the linear summation phenomenon, it was shown that a larger area plasma with a uniform density and temperature profile could be constructed with multi-collisional ICP cells.     

Surface Modification of Nanometre Silicon Carbide Powder with Polystyrene by Inductively Coupled Plasma

An investigation was made into polystyrene （PS） grafted onto nanometre silicon carbide （SIC） particles. In our experiment, the grafting polymerization reaction was induced by a radio frequency （RF） inductively coupled plasma （ICP） treatment of the nanometre powder. FTIR （Fourier transform infrared spectrum） and XPS （X-ray photoelectron spectroscopy） results reveal that PS is grafted onto the surface of silicon carbide powder. An analysis is presented on the effectiveness of this approach as a function of plasma operating variables including the plasma treating power, treating time, and grafting reaction temperature and time.     

Ion Density Distribution in an Inductively Coupled Plasma Chamber

The ion density distribution in the reaction chamber was diagnosed by a Langmuir probe. The rules of the ion density distribution were obtained under the pressures of 9 Pa, 13 Pa, 27 Pa and 53 Pa in the reaction chamber, different radio-frequency powers and different positions. The result indicates that the ion density decreases as the pressure increases, and increases as the power decreases. The ion density of axial position z =0 achieves 5.8×1010 on the center of coil under the power of 200 w and pressure of 9 Pa in the reaction chamber.     

电感耦合等离子体质谱法测定有机相中镎

建立了电感耦合等离子体质谱法(ICP-MS)测定30%(体积分数,下同)磷酸三丁酯(TBP)/煤油和0.5 mol/L 2-噻吩甲酰三氟丙酮(TTA)/二甲苯中镎的分析方法。样品经异丙醇适当稀释或直接进入ICP-MS分析,在有机进样条件下对仪器和操作参数进行优化和选择,研究了有机相和大量²³⁸U在有机基体中引起的基体和质谱干扰,以钍为内标消除基体干扰。研究结果表明:方法的检出限为1×10^-8 g/L(3s,n=10);相对标准偏差(s_r)为0.8%(n=10)(镎质量浓度为2.02μg/L);加标回收率为95.5%～115%。该法适用于动力堆乏燃料后处理流程以及预处理后0.5 mol/L TTA/二甲苯中镎的分析。     

Power characteristics of multiple inductively coupled RF discharges inside a metallic chamber

The characteristics of an innovative configuration of multiple radiofrequency (RF) coils immersed in a large metallic chamber are presented. Water-cooled copper coils were mounted within the slits of double-walled glass tubes, which were immersed into a stainless-steel chamber. The coils were connected in parallel to a gamma-type matching network, powered by an RF generator operating at industrial frequency. Adjustable leads enabled optimisation of the line impedances and thus uniformly distributed RF power across the four coils. Transitions from E- to H-mode and vice versa were measured for all coils at various oxygen pressures between 5 and 25 Pa. A uniform plasma was sustained in H-mode at the absorbed power threshold, which increased monotonously with increasing pressure in the metallic chamber. All coils exhibit the same E- to H-mode transition hysteresis and need the same amount of power for transitioning from E- to H-mode. The setup enables maintaining uniform plasma in virtually any number of coils at high power without the risk of arcing and without the dead volume typical for a classical configuration with coils mounted outside the metallic chamber.     

Extraction Characteristics of Radio Frequency ICP Ion Source

An inductively coupled radio frequency ion source has been developed and its extraction characteristics measured. Beam current density up to 0.11 mA/ cm2 was obtained with argon at a rf discharge power of about 140 W. The dependences of ion beam on the discharge parameters such as rf source power, gas pressure and gas flow rate was studied.     

Numerical Investigation of Flow Fields in Inductively Coupled Plasma Wind Tunnels

Numerical simulations of 10 kW and 110 kW inductively coupled plasma （ICP） wind tunnels were carried out to study physical properties of the flow inside the ICP torch and vacuum chamber with air as tile working gas. Two-dimensional compressible axisymmetric Navier- Stokes （N-S） equations that took into account 11 species and 49 chemical reactions of air, were solved. A heat source model was used to describe the heating phenomenon instead of solving the electromagnetic equations. In the vacuum chamber, a four-temperature model was coupled with N-S equations. Numerical results for tile 10 kW ICP wind tunnel are presented and discussed in detail as a representative case. It was found that the plasma flow in the vacuum chamber tended to be in local thermoehemical equilibrium. To study the influence of operation conditions on the flow field, simulations were carried out for different chamber pressures and/or input powers. The computational results for the above two ICP wind tunnels were compared with corresponding experimental data. The computational and experimental results agree well, therefore the flow fields of ICP wind tunnels can be clearly understood.     

Two-Dimensional Self-Consistent Kinetic Model for Solenoidal Inductively Coupled Plasma

A two-dimensional self-consistent kinetic model was developed to study the influence of the various factors on the electron energy distribution function. These factors include gas pressure the driving frequency, the radius and length of the inductively coupled plasma equipment, the amplitude of the radio-frequency coil current, and the number of turns of rf coils. The spatial profiles of the rf electric field and power density have also been calculated under the same parameters. Numerical results show that the electron energy distribution functions are significantly modified and the spatial profiles of the rf electric field and rf power density are also demonstrated.     

ICP-MS和ICP-AES联合分析63Ni活度浓度

将电感耦合等离子体质谱法（ICP-MS）与电感耦合等离子体原子发射光谱法（ICP-AES）联合使用,结合2种仪器的优势,建立仪器分析和数据处理方法。采用建立的联合方法实测了辐照后镍金属制备63Ni β放射源工艺监控样品的63Ni活度浓度,并将所测结果与液体闪烁计数器法（LSC）测量结果进行对比。结果表明,2种方法所测结果的最大偏差为5.1%,测量结果的不确定度为4.4%（k=2）,证明该联合测量方法准确可行。      

Plasma Formed in Argon,Acid Nitric and Water Used in Industrial ICP Torches

Inductively coupled plasmas （ICPs） are used in spectrochemical analyses. The introduction of the sample by means of an aerosol are widely used. The introduction and the total evaporation of the aerosol is required in order to obtain a good repeatability and reproducibility of analyses. To check whether the vaporization of the aerosol droplets inside the plasma is completed, a solution could be used to compare the experimental results of the emission spectral lines with theoretical results. An accurate calculation code to obtain monatomic spectral lines intensities is therefore required, which is the purpose of the present paper. The mixtures of argon, water and nitric acid are widely used in spectrochemical analyses with ICPs. With these mixtures, we calculate the composition, thermodynamic functions and monatomic spectral lines intensities of the plasma at thermodynamic equilibrium and at atmospheric pressure. To obtain a self sufficient paper and also to allow other researchers to compare their results, all required data and a robust accurate algorithm, which is simple and easy to compute, are given.     

Optical Emission Spectroscopic Studies of ICP Ar Plasma

The ion line of 434.8 nm and atom line of 419.8 nm of Ar plasma produced by an inductively coupled plasma （ICP） were measured by optical emission spectroscopy and the influences from the working gas pressure, radio-frequency （RF） power and different positions in the discharge chamber on the line intensities were investigated in this study. It was found that the intensity of Ar atom line increased firstly and then saturated with the increase of the pressure. The line intensity of Ar^＋, on the other hand, reached a maximum value and then decreased along with the pressure. The intensity of the line in an RF discharge also demonstrated a jumping mode and a hysteresis phenomenon with the RF power. When the RF power increased to 400 W, the discharge jumped from the E-mode to the H-mode where the line intensity of Ar atom demonstrated a sudden increase, while the intensity of Ar^＋ ion only changed slightly. If the RF power decreased from a high value, e.g., 1000 W, the discharge would jump from the H-mode back to the E-mode at a power of 300 W. At this time the intensities of Ar and Ar^＋ lines would also decrease sharply. It was also noticed in this paper that the intensity of the ion line depended on the detective location in the chamber, namely at the bottom of the chamber the line was more intense than that in the middle of the chamber, but less intense than at the top, which is considered to be related to the capacitance coupling ability of the ICP plasma in different discharge areas.     

ICP-MS测量超痕量钚时质谱干扰的消除及水中钚的测定

研究了感应耦合等离子体质谱(ICP-MS)测定超痕量钚时的质谱干扰及干扰元素的去除;建立了环境水样中超痕量钚的测定方法。方法所用的解吸液适于ICP-MS直接进样,并有效地消除铅等元素形成的多原子离子干扰。测量了溶液中的m／z238和2％HNO3空白液中的^239Pu和^242Pu计数率,对测量结果进行校正。方法的本底为20fg,方法对^239Pu的检出限为43fg,测定限为88fg。所分析的水样中,井水中的^239Pu含量低于检出限,地表水中^239Pu的含量高于检出限,湖水和河水中的^239Pu高于测定限,但属于全球沉降引起的本底,不会对公众造成辐射危害。     

Thermochemical Nonequilibrium 2D Modeling of Nitrogen Inductively Coupled Plasma Flow

Two-dimensional (2D) numerical simulations of thermochemical nonequilibrium in?ductively coupled plasma (ICP) flows inside a 10-kW inductively coupled plasma wind tunnel (ICPWT) were carried out with nitrogen as the working gas. Compressible axisymmetric Navier-Stokes (N-S) equations coupled with magnetic vector potential equations were solved. A four-temperature model including an improved electron-vibration relaxation time was used to model the internal energy exchange between electron and heavy particles. The third-order accuracy elec?tron transport properties (3rd AETP) were applied to the simulations. A hybrid chemical kinetic model was adopted to model the chemical nonequilibrium process. The flow characteristics such as thermal nonequilibrium, inductive discharge, e?ects of Lorentz force were made clear through the present study. It was clarified that the thermal nonequilibrium model played an important role in properly predicting the temperature field. The prediction accuracy can be improved by applying the 3rd AETP to the simulation for this ICPWT.